Rheumatology + Orthopaedics Flashcards
Clinical presentation of septic arthritis
Signs + symptoms
- Painful, hot, red, swollen joint - usually single joint
- Restricted movement/stiffness
- Rapid onset
- Systemic symptoms (not always) - fever, malaise, sweats, rigors
Which joints are most commonly affected by septic arthritis?
Hip and knee
What percentage of septic arthritis is polyarticular?
20%
List risk factors for septic arthritis
- Disease of joint e.g. osteoarthritis
- Prosthetic joint
- Recent joint surgery
- Leg ulceration
- Trauma to joint/skin
- IVDU
- Immunosuppression
Describe the possible routes of infection in septic arthritis and give examples of each
- Direct inoculation e.g. joint surgery
- Contigious spread from adjacent bone e.g. osteomyelitis
- Haematogenous seeding from a distant site e.g. bacteraemia due to meningitis
What is the most common causative organism of septic arthritis? List other common causes of septic arthritis
- Staphylococcus aureus most common
- Neisseria gonorrhoea in sexually active
- Group A strep - strep pyogenes most common
- Haemophilus influenza
- E. Coli
Differential diagnosis of acute monoarthritis
- Septic arthritis
- Crystal arthritis - gout or pseudogout
- Reactive arthritis
- Seronegative arthritis
- Haemarthrosis
- Specific to site e.g. knee - bursitis
How can differential diagnosis for acute monoarthritis be narrowed down using a patient’s history?
- Septic arthritis - usually rapid onset, Hx orthopaedic interventions, primary joint disease, IVDU, immunosuppression, sexual history (gonococcal)
- Reactive arthritis - asymmetrical and polyarticular, symptoms of urethritis, conjunctivitis, diarrhoea, rash, travel history (traveller’s diarrhoea)
- Crystal deposition - rapid onset, previous episodes acute attack in same or other joint with spontaneous resolution, use of diuretics, history of renal calculi, alcoholism, presence of tophi, foot joints involved (gout)
- Ankylosing spondylitis - eye inflammation, low back pain
- Psoriatic arthritis - polyarticular, skin/nail symptoms - patches, pitting
- Haemarthrosis - coagulopathy, anticoagulant medications, trauma
Important points in clinical examination of acute monoarthritis
- Affected joint and joints above and below - ROM, soft tissue around joint, effusion
- Skin
- Eyes
- Systemic symptoms - observations, relevant systems e.g. eyes, skin
Which investigations should be used in acute monoarthritis?
+ interpretation
**Joint arthrocentesis for synovial fluid aspiration in any hot, swollen, tender joint with restricted movement. **
(Considered septic arthritis until proven otherwise)
* Send for - WCC, crystal analysis, gram staining, culture
Bloods
* FBC - WCC (infection), Hb (haemarthrosis)
* ESR, CRP - infection, inflammatory/autoimmune
* Blood culture - infection, done even if apyrexial
* Serum urate - gout
* ANA and RF - rheumatoid arthritis, other inflammatory causes
* U&Es - baseline (e.g. prior to antibiotics), may be deranged in sepsis
* LFTs - baseline
Imaging
* Plain X-ray films of affected joint as baseline
* US for diagnosis/guiding aspiration
* MRI if osteomyelitis suspected or deep joint
Bedside
* MSSU, urinalysis
* Wound swab
* Sputum
How should joint arthrocentesis be carried out in acute monoarthritis?
- Refer to orthopaedics if joint prosthesis or hip joint (will require US guidance)
- Should be carried out in sterile environment
- Use smallest needle possible
- Can be done in patients on anticoagulants e.g. warfarin
- Withdraw as much fluid as possible for symptomatic relief, may need to massage joint to encourage drainage
- Cellulitis of skin over joint is relative contraindication
Features of synovial fluid analysis which suggest septic arthritis
- Colour - yellow/green
- Clarity - cloudy/opaque
- Increased viscosity
- WCC > 50,000 cells/mm3
- > 75% neutrophils
- Gram stain positive
- Negative crystals
Features of synovial fluid analysis which suggest a non-inflammatory pathology
- Colour - straw/yellow
- Clarity - translucent
- High viscosity
- WCC - 200-2000 cells/mm3
- <25% neutrophils
- Gram stain negative
- Negative crystals
Features of synovial fluid analysis which suggest inflammatory cause of arthritis
- Colour - yellow
- Clarity - cloudy
- Viscosity - decreased
- WCC - 2000-50000 cells/mm3
- > 50% neutrophils
- Gram stain negative
- Crystals positive
Features of synovial fluid analysis which suggest haemarthrosis
- Colour - red/xanthochromic
- Bloody
- WCC - 200-2000mm3
- 50-75% neutrophils
- Gram stain negative
- Crystals negative
Classification system for septic arthritis
Newman’s class
A - isolation of pathogenic organism from joint
B - isolation of pathogenic organism from another source
C - typical clinical features and turbid joint fluid in presence of previous antibiotic use
D - suggestive pathology or post-mortem features of septic arthritis
Risk factors for gout
- Male gender
- Obesity
- High purine diet - meat and seafood
- Alcohol
- Diuretics
- CVD or CKD
- Family history
Which joints are typically affected by gout?
- Metarsophalangeal joint (base of big toe)
- Carpal joints
- Carpometacarpal joints (base of thumb)
Describe the crystals seen in gout
Negatively birefringent of polarised light
Monosodium urate crystals
Needle shaped
X-ray findings in gout
- Joint space maintained usually
- Lytic lesions in bone
- Punched out erosions - sclerotic borders, overhanging edges
Management of acute gout flare
- NSAIDs first line (+ PPI)
- Colchicine second line if NSAIDs contraindicated e.g. renal impairment, significant heart disease
- Steroids considered third line
Common side effects of colchicine and how to prevent
GI upset - diarrhoea
Lower dose
Describe long-term management of gout
Lifestyle - healthy diet, avoid alcohol, maintain healthy weight
Urate-lowering therapy - started 2-4 weeks after acute flare has settled
* Offerred if multiple/troublesome flares, CKD 3-5, diuretic therapy, tophi, chronic gouty arthritis
* Monitor serum urate levels - aim for <360 micromol/L or lower if tophi/arthritis, frequent flares despite urate below target
* Allopurinol or febuxostat first line (allopurinol in CVD)
Mechanism of action of allopurinol in gout treatment
Xanthine oxidase inhibitor - reduces production of uric acid (product of purine metabolism)
Crystals seen in pseudogout
Positive birefringement of polarised light
Calcium pyrophosphate crystals
Rhomboid shaped
X-ray findings in pseudogout
Chondrocalcinosis - thin white line in middle of joint space caused by calcium deposition (pathognomonic)
Other changes - LOSS
L - loss of joint space
O - osteophytes
S - subarticular sclerosis
S - subchondral cysts
How is pseudogout managed?
- Symptomatic management - NSAIDs, colchicine, joint aspiration, steroid injections, oral steroids
- Arthrocentesis in severe cases
Define gouty tophi. Where are they most commonly found?
- Subcutaneous deposits of uric acid
- Small joints and connective tissue of hands, elbows, ears
- DIP joints in hands most commonly affected
Management of septic arthritis
Joint aspiration to remove purulent material + for symptomatic relief - closed aspiration or arthroscopic drainage, aspirate to dryness, may need serial aspiration
Empirical IV antibiotics until organism/sensitivities known -
* Native joint - IV flucloxacillin
* Penicillin allergy or MRSA suspected - IV vancomycin
* High risk for gram negative - add IV gentamicin
* Prosthetic joint - IV vancomycin (+/- IV gentamicin)
* Gonococcal infection suspected - cephalosporin
Native joint - 2 weeks IV, 4 weeks oral
Prosthetic joint - 6 weeks IV
What do crystals in synovial fluid indicate?
Gout, pseudogout or septic arthritis - can be co-existent
Describe the pattern of joint involvement in RA
Symmetrical
Polyarticular
Distal small joints - hands + feet
* Hands - MCP, PIP
* Wrist
* Ankle
* Can be larger joints e.g. knees, shoulders, elbows
Symptoms of inflammatory arthritis
- Pain - worse after rest, improves with activity (opposite to OA)
- Swelling
- Warmth
- Redness
- Tenderness
- Stiffness - early morning stiffness >1 hour
- Persistent - generally accumulates joints over time
- Systemic symptoms - fatigue, weight loss, flu-like illness, muscle aches and weakness
Signs of RA
Synovitis - boggy on palpation
Positive squeeze test - pain when squeezing metacarpal/tarsal joints
Deformity
* Swan neck - MCP flexion, PIP hyperextension, DIP flexion
* Boutonniere’s - PIP flexion, DIP hypertextension
* Z-thumb - CMC flexion, MCP hypertextension, PIP flexion
* Ulnar deviation - deformity of MCP joints, fingers deviate towards ulnar side
Rheumatoid nodules - firm, hard swellings over extensor surfaces
Extra-articular features
* Ocular - scleritis, episcleritis, Sicca syndrome (secondary Sjogren’s)
* Cardiorespiratory - pleural effusions, pulmonary nodules, pulmonary fibrosis, pericarditis, serositis
* Splenomegaly
* Peripheral neuropathy
* Anaemia of chronic disease
* Amyloidosis
* Lymphadenopathy
* Carpal tunnel syndrome
* Felty’s syndrome - RA, neutropaenia, splenomegaly
Differential diagnosis for RA
How to differentiate between differentials and RA
- Psoriatic arthritis - small joints of hand and feet but less symmetrical, DIP involved, skin/nail symptoms
- Polyarticular gout - tophi, risk factors for gout
- Osteoarthritis - worse with movement, better with rest, <1 hour early morning stiffness, less symmetrical, larger joints
- SLE - polyarthritis in small joints of hands and feet but usually non-deforming, additional signs e.g. rash, mouth ulcers, alopecia, Raynaud’s, Sicca syndrome
- Polymyalgia rheumatica - shoulder pain and stiffness primarily, older woman
- Reactive arthritis - recent infection, can cause symmetric hand and feet arthritis
- Sarcoidosis - CXR
- Septic arthritis - acutely painful, hot, swollen joint, signs of sepsis e.g. fever
- Seronegative spondyloarthritis - history of psoriasis, back pain, bowel problems
Define palindromic rheumatism
Self-limiting short episodes of inflammatory arthritis with joint pain, stiffness, swelling typically affecting only a few joints.
Last 1-2 days, then completely resolve.
Positive antibodies (RF, anti-CCP) with palindromic rheumatism –> progression to full RA more likely
RA consequences in the cervical spine
Atlantoaxial subluxation
* C2 (axis) and odontoid peg shift within C1 (atlas)
* Due to local synovitis and damage to ligaments and bursa around odontoid peg
* Can cause spinal cord compression and is an emergency
* Important if having GA requiring intubation - MRI pre-op to assess
Investigations used in RA diagnosis
- CRP and ESR - usually elevated in RA (40% normal)
- Rheumatoid factor - present in 60-70% RA
- Anti-CCP if negative for RF - present in 80% RA
- Imaging - US (synovitis), X-ray (hands and feet), MRI
Describe the early and late X-ray changes seen in RA
Early
* Peri-articular osteopaenia
* Soft tissue swelling
* Loss of joint space
Late
* Peri-articular joint erosion
* Joint destruction
* Subluxation
Compare the antibodies used in diagnosis of RA
- Rheumatoid factor vs anti-CCP
- Similar sensitivity but anti-CCP higher specificity (90-95%)
- Test for anti-CCP in patients with suspected RA who are RF negative
What is rheumatoid factor?
How is it detected?
What does it indicate in RA?
Circulating antibody (usually IgM) that reacts with the Fc portion of own IgG
Detected by either:
Rose-Waaler test - sheep red cell agglutination
Latex agglutination test (less specific)
Positive in 70-80% of RA, high titre associated with severe progressive disease (not a marker of disease activity)
Conditions associated with rheumatoid factor
- Rheumatoid arthritis
- Felty’s syndrome (RA, splenomegaly, neutropaenia) - 100%
- Sjogren’s syndrome - 50%
- Infective endocarditis - 50%
- SLE - 20-30%
- Systemic sclerosis - 30%
- General population - 5%
- Rarely - TB, HBV, EBV, leprosy
When should a patient with suspected RA have a routine/urgent referral?
- Refer for appointment within 3 weeks for persistent synovitis of unknown cause
- Urgent referral (within 3 working days) if small joints of hand or feet affected, more than one joint affected, delay of 3 months or longer from onset of symptoms to presentation
Even if CRP/ESR, negative anti-CCP or RF
Diagnostic criteria used in RA
American College of Rheumatology/European League Against Rheumatism (ELAR)
Score based on
* Joints involved - more and smaller joints score higher
* Serology - rheumatoid factor and anti-CCP
* Inflammatory markers - ESR, CRP
* Duration of symptoms - more or less than 6 weeks (longer scores)
Score of 6 or more - diagnostic for RA
Functional assessments/disease monitoring scores used in RA
DAS28 - disease activity score
* Assessment of 28 joints
* Points given for swollen joints, tender joints, ESR/CRP result
* Used to monitor disease activity and response to treatment
HAQ-II - health assessment questionnaire disability index
* Patient reported - difficulty with ADLs
SF-36 - short form 36
* Patient reported
* Health-related quality of life
Risk factors for worse prognosis in RA
- Younger onset
- Male
- More joints and organs affected
- Presence of RF and anti-CCP
- Erosions seen on X-ray
Describe approach to management of RA
Induction/initiation therapy
* Step-up approach - introduce and escalate single drug to maximum tolerated dose, if ongoing disease activity add a further drug
* Step-down approach - several drugs started at once then gradually withdrawn
* Parallel - combination introduced at same time and maintained
Monitor response to treatment with CRP and disease activity score (e.g. DAS28)
Treat acute flare-ups
How are acute RA flares treated?
Oral NSAIDs for pain/stiffness - ibuprofen, naproxen, diclofenac (+ PPI)
COX-2 inhibitors e.g. etoricoxib
Glucocorticoids - oral prednisolone, IM/intra-articular methylprednisolone or triamcinolone acetonide
What is the first line long-term treatment for RA?
CsDMARDs - offer first line and within 3 months of symptom onset
* Methotrexate
* Leflunomide
* Sulfalazine
* Hydroxychloroquine if mild or palindromic disease
Methotrexate
* Mechanism of action
* Dose frequency
* Side effects
* Monitoring requirements
* Pregnancy considerations
* Interactions
- Folate metabolism antagonist - inhibits dihydrofolate reductase
- Injection or tablet once a week, also folic acid 5mg once a week on a different day
- Side effects - mouth ulcers, mucositis, liver toxicity, bone marrow suppression and leukopaenia, ?pulmonary fibrosis
- Monitoring - FBC, LFTs
- Contraindicated in pregnancy - teratogenic
- Interactions - trimethoprim/co-trimoxazole increases risk of marrow aplasa, high dose aspirin increased risk of methotrexate toxicity as reduced excretion
Advise for methotrexate and pregnancy
Avoid pregnancy for at least 6 months after treatment stopped
Men using methotrexate need to use effective contraception for 6 months after treatment
Leflunomide
* Mechanism of action
* Side effects
* Pregnancy considerations
- Interferes with pyrimidine production - component of RNA and DNA
- Side effects - mouth ulcers, mucositis, hypertension, rashes, peripheral neuropathy, liver toxicity, bone marrow suppression and leukopaenia
- Contraindicated - pregnancy (teratogenic), women and men
Sulfalazine
* Mechanism of action
* Dosing regimen
* Side effects
* Monitoring requirements
* Pregnancy considerations
- Immunomodulatory - immunosuppressive and anti-inflammatory, against folate, T and B cells
- Daily dosing
- Side effects - GI, headache, rash, temporary male infertility (reduced sperm count), bone marrow suppression
- Monitoring requirements - FBC, U+Es, LFTs
- Safe in pregnancy - folic acid 10mg daily, started 3 months pre-conception
Hydroxychloroquine
* Mechanism of action
* Dosing regimen
* Side effects
* Monitoring
* Pregnancy considerations
- Immunosuppression via interaction with toll-like receptors, disrupting antigen presentation and increasing pH in lysosomes of immune cells
- Daily dose
- Side effects - nightmares, reduced visual acuity (macular toxicity), liver toxicity, skin pigmentation, headache, nausea, muscle pain, rash
- Monitoring requirements - ocular after 5 years
- Safe in pregnancy
Second, third and fourth line management RA
- Second line - combination of two conventional DMARDs
- Third - methotrexate plus biological therapy, usually TNF inhibitor
- Fourth - methotrexate plus rituximab
Options of biological DMARDs for RA and examples of each
- Anti-TNF - adalimumab, inflixumab, etanercept, golimumab, certolizumab pegol
- Anti-CD20 - rituximab
- Anti-IL6 - sarilumab
- Anti-IL6 receptor - tocilizumab
- JAK inhibitors - tofacitinib, baricitinib
Criteria for commencing biologic therapy in RA
British society rheumatology/NICE guidelines
* Failed on at least two conventional DMARDs, one of which must be methotrexate unless contraindicated
* Severe disease - DAS28 >5.1 on at least two occasions one months apart
* Continue only if adequate response within first six months, defined as reducting in DAS-28 of >1.2
Screening required before commencing bDMARDs
- Viral hepatitis and HIV (including anti-core Ab)
- Varicella
- CXR and IGRA (TB)
- Vaccination - influenza, pneumococcal
Contraindications to bDMARDs
- Active infection
- Active or latent TB
- Pregnancy
- Malignancy
- Diverticular disease (IL-6)
Monitoring required for bDMARDs
- Infections
- Malignancy
- Bloods (FBC, LFTs)
- Awareness with vaccination
Side effects of anti-TNF drugs
- Vulnerability to severe infections and sepsis
- Reactivation of TB and hepatitis B
Side effects of rituximab
- Vulnerability to severe infections and sepsis
- Night sweats
- Thrombocytopaenia (low platelets)
- Peripheral neuropathy
- Live and lung toxicity
Describe the types of tissues which make up bones
Cortical (compact/tubular) bone
* Shafts of long bones
* Slow turnover rate
* Stiffer, more resistant to torsion and bending
Cancellous (spongey/trabecular) bone
* Ends of long bones, cuboidal/flat bones
* Higher turnover rate, more remodelling
* More elastic
Matrix - organic (collagen, proteins) and inorganic (calcium, phosphorus)
Cells - osteoprogenitor, osteocytes, osteoblasts, osteoclasts
Describe the sections of bones and how these differ in adults vs children
- Epiphysis - end of bone
- Diaphysis - shaft, where nutrient artery enters bone
- Metaphysis - transitional flared area between diaphysis and epiphysis
- Physis (growth plate) - in children only, between metaphysis and epiphysis
List the types of fracture healing and when these occur
- Indirect healing (secondary) - more common, no anatomical reduction or rigid stabilisation, more similar to endochondral bone formation with fibrocartilaginous soft callus –> bony hard callus then osteoclastic remodelling
- Direct healing (primary)- when bone fragments are ‘artificially’ fixed together (surgically) with compression, no callus formation just new bone formation through osteoblastic formation and osteoclastic resorption
List the stages of indirect fracture healing
Inflammation –> repair –> remodelling
1. Fracture haematoma and inflammation (6-8 hours post-injury) - blood from broken vessels form clot, swelling and inflammation at fracture site
2. Fibrocartilage (SOFT) callus (3 weeks post-injury) - granulation tissue formed, fibroblasts and osteogenic cells produce collagen, chondrocytes begin to produce fibrocartilage which gives stability
3. Bony (HARD) callus (3-4 months post-injury) - osteoblasts make woven bone
4. Bone remodelling - osteoclasts remodel woven bone –> compact and trabecular bone
Describe the role of movement in fracture healing
- Movement and weight bearing are important in healing - bone laid down in relation to stress put across it
- A degree of movement desirable but excessive movement disrupts healing tissue and affects cellular differentiation (stabilisation useful)
Describe the process of direct fracture healing
- Direct formation of bone without callus formation
- Inflammation –> formation of bone via osteoclastic absorption and obsteoblastic formation via cutting cones at fracture site
- Initially randomly laid down then remodelled
Describe the stages of X-ray findings seen during normal fracture healing
- Widened fracture line (10-14 days) - blurring of fracture ends, finding in both normal and abnormal healing (should narrow in normal healing)
- Callus formation (2 weeks) - initially immature, fluffy, indistinct –> dense, organised, bridges, ossified, endosteal callus obliterates the fracture line
- Radiologic union - mature external bridge callus across fracture, very variable time depending on fracture site
What factors influence callus size during fracture healing?
Increased
* Larger bones
* Diaphyseal fracture
* More motion - cast vs surgical fixation
* Comminution
* Infection
* Steroids
Decreased
* Smaller bones
* Metaphyseal fracture
* Impaction
* Rigid fixation
When is a fracture ‘healed’?
Fracture union - clinical diagnosis
* No tenderness at fracture site
* No motion at fracture site
* Stable - weightbearing without support
(Identifiable before radiologic union - too little bridging bone to see on X-ray)
Radiologic union - much later
* Continuous external bridge mature callus
* Re-established medullary space
List the factors which influence the rate of fracture healing
- Local soft tissue trauma
- Fragment vascularity
- Patient age
- Method of treatment - rigid fixation heal faster
- Fracture gap
- Motion - longer if moving
- Infection
- Underlying bone disease
- Intra-articular fracture slower (synovial fluid slows new bone formation)
- Steroids
Define disuse atrophy in fracture healing
- Acute osteoporosis which occurs as a result of normal fracture healing
- At and distal to fracture site
- Occurs 5-7 weeks after immobilisation
- Reversal takes 4+ weeks
- Risk of fragility fractures esp. in elderly
Define compound fracture and describe the mechanisms of compound fractures
Open fracture - skin overlying fracture is broken, allowing communication between the fracture and external environment
Compound from within (inside-out)
* Broken end of bone breaks through or pierces the skin
Compound from without (outside-in)
* External violence causes laceration or tissue trauma
* Higher likelihood of contamination
Classification system for open fractures
Gustillo-Anderson classification
* Type 1 - <1cm
* Type 2 - 1-10cm, >1cm wound with moderate soft tissue damage
* Type 3 - >10cm or high energy, extensive soft tissue damage (or segmental fractures, extensive contamination, high velocity injuries)
* 3A - adequate tissue for coverage
* 3B - extensive periosteal stripping, requires flap (inadequate soft tissue coverage)
* 3C - vascular injury requiring vascular repair
Scoring system for type 3C open fractures
Mangled extremity severity system (MESS)
* Limb ischaemia - time (>6 hours) and clinical signs (pulse, temperature, sensation)
* Patient age (<30, 30-50, >50)
* Shock - hypotension
* Injury mechanism - low - very high energy
Complications of open fractures
- Soft tissue infection
- Osteomyelitis
- Tetanus
- Crush syndrome - traumatic rhabdomyolysis (shock and kidney failure after crushing of skeletal muscle)
- Skin loss
- Non-union
- Amputation
Describe the emergency management of open fractures
BOAST guideline
* Control bleeding
* Remove gross debris
* Cover with sterile dressing - photograph before so dressing can stay on until definitive management in theatre
* Realignment and splinting
* IV antibiotics
* Tetanus prophylaxis
* Assessment of vascular and neurological status - repeat systematically, especially after reduction/splinting
* Imaging - may require trauma CT, angiography
Describe the definitive management of open fractures
- Debridement using fasciotomy lines for wound extension - timing dependant on level of contamination of wound (e.g. immediately if agricultural, sewage)
- Irrigation - 6L saline
- ?Delayed primary amputation
- Stabilisation - often requires external fixator
- Multidisciplinary approach - orthropaedic, plastics, rehabilitation
How do clavicle fractures usually occur?
What is the most common location of clavicle fracture? Why?
- Fall onto outstretched hand
- Direct blow to shoulder
- Middle third/midshaft is most easily fractured - thinnest with no ligamentous/muscle attachments
- Middle 1/3 - 80%
- Lateral 1/3 - 15%
- Medial 1/3 - 5%
Describe the management of clavicle fractures
- Usually conservative - depends on location, shortening, displacement, patient fractures
- Conservative management - immobilisation with simple triangular sling, analgesia
- If more than 2cm of shortening, lateral, comminuted/Z pattern - may need open reduction with internal fixation (ORIF)
What are the potential complications of clavicle fractures?
- Delayed union
- Malunion
- Non-union
- Palpable bump
- Stiffness
- Infection
- Palpable metalwork
Which X-ray views should be used for suspected clavicular fractures?
- Frontal (AP)
- Cephalic tilt (15-45 degree)
How should clavicle fractures be described radiologically?
Fracture
* Location of fracture along shaft
* Angulation and fracture end displacement (including direction)
* Comminution
* Degree of overlap - measure
Associated findings and relevant negatives
* Acromioclavicular joint and sternoclavicular joint alignment
* Coracoclavicular distance
* Glenohumeral joint
Associated traumatic injuries
* Rib fractures
* Vertebral fractures
* Scapular fractures - floating shoulder
* Pneumothorax
Describe the types of shoulder dislocation, the mechanisms of injury which cause them and their prevalence
- Anterior (>90%) - head of humerus moves anteriorly in relation to glenoid cavity
- Occurs when arm if forced posteriorly while abducted and extended at the shoulder, trauma e.g. fall on an outstretched arm, sports injuries
- Posterior (2-4%) - associated with uncoordinated muscle contraction e.g. seizure or electric shock
- Inferior (luxatio erecta, <1%) - high-energy, hyperabduction force to arm
Describe the clinical presentation of shoulder dislocations
- Present acutely after injury - usually aware of dislocation
- Severe pain and restriction of movement of shoulder
- Prominent acromion, shoulder flattened (loss of symmetrical roundness), prominent humeral head, arm slighly abducted, elbow flexed, forearm internally rotated and supported by other hand
- Empty glenoid fossa - palpable dent where head of humerus should be
- Inferior dislocation - arm fixed, abducted, overhead position
What is the most commonly dislocated large joint?
Shoulder - approximately 50%
Injuries associated with shoulder dislocations
Damage to the glenoid labrum - rim of cartilage around glenoid cavity which creates deeper socket for head of humerus
* Bankart lesions - tears to anterior labrum, occurs with repeated anterior subluxations or dislocations
- Hill-Sachs lesions - compression fractures of posterolateral part of head of humerus when shoulder dislocates anteriorly, makes shoulder less stable and at risk of further dislocations
- Axillary nerve damage - loss of sensation in ‘regimental badge’ area over lateral deltoid, motor weakness in deltoid and teres minor muscles
Fractures
* Humeral head
* Greater tuberosity of humerus
* Acromion of scapula
* Clavicle
- Rotator cuff tears - especially in older patients
- Brachial plexus injuries
Which imaging techniques are used in shoulder dislocation?
Xray - may not be required before reduction
* Frontal (AP)
* Y-view (lateral)
* Axillary film, arm abducted at 70-90 degrees, taken from angle of 45 degrees through axilla - for posterior dislocation
MRI arthrogram
* MRI with contrast injected into shoulder joint
* To assess soft tissue damage e.g. Bankart and Hill-Sachs lesions
Arthroscopy - camera into joint to visualise structures
Special test used to assess for shoulder instability
Apprehension test - shoulder instability, often positive after previous anterior dislocation or subluxation
Shoulder abducted to 90 degress, elbow flexed to 90 degrees, shoulder externally rotated while watching patient
Patient will be anxious/apprehensive if unstable shoulder
Define subluxation
Partial dislocation of joint
Shoulder dislocation appearance on X-ray
Anterior
* AP view - humeral head lies medial and inferior to glenoid fossa
* Lateral view - humeral head anterior and inferior to glenoid fossa
* Humeral head also inferior to coracoid process
Posterior
* AP view - glenohumeral joint widened and humeral head has ‘light bulb’ appearance due to forced internal rotation of humerus
* Lateral view - humeral head posterior to glenoid fossa
What are the roots of the brachial plexus?
Anterior rami of spinal nerves C5, 6, 7, 8 and T1
Describe the path of the brachial plexus and its divisions
- Roots leave spinal cord via intervertebral foramina of vertebral column
- Pass between anterior and medial scalene muscles to enter the base of the neck
- Roots converge at base of neck to form trunks - superior (C5 + 6), middle (C7), inferior (C8 + T1)
- Trunks cross posterior triangle of neck
- Trunks divide into anterior and posterior divisions, leave the posterior triangle and pass into axilla
- Anterior and posterior divisions combine to form three cords named by position relative to axillary artery
- Lateral cord - anterior division of superior trunk, anterior division of middle trunk
- Posterior cord - posterior divisions of superior, middle and inferior trunk
- Medial cord - anterior division of inferior trunk
- Major branches - musculocutaneous nerve, axillary nerve, median nerve, radial nerve, ulnar nerve
Roots, motor functions, sensory functions of musculocutaneous nerve
- Roots - C5, 6, 7 –> superior + middle trunks –> lateral cord
- Motor functions - brachialis, biceps brachii, coracobracialis (elbow/shoulder flexion)
- Sensory functions - gives off lateral cutaneous branch of forearm, innervates lateral half of anterior forearm and small lateral portion of posterior forearm
Axillary nerve roots, motor function, sensory function
- Roots - C5 + 6 –> superior trunk –> posterior cord
- Motor function - teres minor and deltoid muscles, abduction (15-90 degrees), flexion, extension and rotation of shoulder
- Sensory function - gives off superior lateral cutaneous nerve, innervates inferior deltoid region (regimental badge area)
Median nerve - roots, motor functions, sensory functions
- Roots - C6, 7, 8 and T1 –> superior, middle and inferior trunks, lateral and medial cords
- Motor functions - most flexor muscles of forearm, thenar muscles, lateral lumbricals associated with index and middle fingers (wrist and 2rd and 3rd digit flexion, thumb opposition and flexion, pronation)
- Sensory functions - gives off palmar cutaneous branch which innervates lateral palm and digital cutaneous branch which innervates the lateral three and a half fingers on the palmar surface of the hand
Radial nerve - roots, motor functions, sensory functions
- Roots - C5, 6, 7, 8, T1 –> superior, middle and inferior trunks –> posterior cord
- Motor functions - triceps brachii, muscles in posterior compartment of forearm (extension of elbow and wrist)
- Sensory functions - posterior of arm and forearm, posterolateral aspect of hand, proximal half of posterior thumb, index finger and lateral half of middle finger
Ulnar nerve - roots, motor functions, sensory functions
- Roots - C8 + T1 –> inferior trunk –> medial cord
- Motor function - muscles of hand (except thenar muscles and two lateral lumbricals), flexor carpi ulnaris and medial half of flexor digitorum profundus (abduction of fingers, flexion of medial digits, adduction of thumb)
- Sensory function - anterior and posterior surfaces of medial one and a half fingers and associated palm area
Describe the clinical assessment of shoulder dislocations
Assess for
* Fractures
* Vascular damage - pulses, CRT, pallor
* Nerve damage - loss of sensation in regimental patch area (axillary nerve damage)
Describe the emergency management of shoulder dislocations
- Relocate/reduce shoulder as soon as safely possible - muscle spasm which occurs over time makes it harder to relocate and increases risk of neurovascular injury during relocation
- Various methods of closed reduction
- Relocation usually done in ED
- Exclude fractures before reduction
- Analgesia, muscle relaxants and sedation used during relocation as appropriate, gas and air may be used
- Broad arm sling used to support arm after relocation
- X-ray performed post-reduction to ensure success
- Immobilisation after reduction
- May require surgical management
Indications for surgical management of shoulder dislocation
- Unsuccessful closed reduction
- Displaced Bankart lesion
- Recurrent shoulder dislocations
- If young and active early surgery may be required to prevent recurrent dislocations in the future
Follow-up required for shoulder dislocations
- High risk of recurrent dislocations, especially in young patients
- Physiotherapy to reduce risk of further dislocations
- May require shoulder stabilisation surgery - prolonged recovery peroid (3+ months)
Risk factors for proximal humerus fractures
- Elderly - >65
- F>M
- Osteoporosis
- High energy trauma
Classification of proximal humerus fractures
Neer classification - describes the number of fracture parts and their displacement
Parts:
* Articular surface (humeral head)
* Greater tuberosity
* Lesser tuberosity
* Humeral shaft
Displacement for each part if
* >1cm
* 45 degree angulation
What is the anatomical vs surgical neck of the humerus? What are their significances in proximal humeral fractures?
- Anatomical - residual epiphyseal plate, oblique angle, divides the head of the humerus from the greater and lesser tubercles
- Rare to have fractures through anatomical neck, if displaced by >1cm risk of avascular necrosis to the humeral head
- Surgical - distal to greater tubercle and lesser tubercle, proximal to deltoid tuberosity
- Most proximal humerus fractures through surgical neck (in children most common is greensick fracture through surgical neck)
Mechanism of injury of proximal humerus fractures
- Older patients - fall on an outstretched hand
- Younger patients - high-energy trauma
Proximal humeral fractures presentation
- Pain and swelling
- Decreased motion
- Ecchymosis of chest, arm and forearm
How are proximal humeral fractures assessed?
Neurovascular examination
* Axillary nerve injury most common - determine deltoid muscle function and lateral shoulder sensation
* Arterial injury may be masked by extensive collateral circulation preserving distal pulses
Examine for concomitant chest wall injuries
X-rays - AP of scapula and glenohumeral joint (Grashey), axillary view, lateral Y view of scapula
Sometimes requires CT, rarely MRI for soft tissue injury
Management of proximal humeral fractures
Conservative - sling immobilisation followed by progressive rehabilitation:
* Minimally displaced
* <2 parts
* Not a surgical candidate
* Severely comminuted, 4 parts
Open reduction, internal fixation
* 2 parts, displaced
* Greater tuberosity displaced >5mm
* 3/4 parts in young patient
Arthroplasty
* Hemiarthroplasty - young patient with fracture not suitable for fixation (poor outcomes)
* Reverse shoulder replacement - unable to fix and rotator cuff defunctioned due to tuberosity involvement
Complications of proximal humerus fractures
- Decreased ROM
- Pain
- Non-union
- Axillary nerve palsy
Describe the mechanism of injury of humeral shaft fractures
Bimodal distribution
* Young - high energy trauma
* Elderly - osteopaenic, low energy
Describe the classification of humeral shaft fractures
Location
* Proximal
* Middle
* Distal 1/3
Pattern
* Spiral
* Transverse
* Comminuted
Holstein-Lewis
* Spiral fracture of the distal 1/3 of shaft associated with radial nerve palsy
Assessment of humeral shaft fractures
- Examine limb alignment - shortening and varus deformity
- Pre-operative/reduction neurovascular exam is critical - examine and document status of radial nerve pre- and post-reduction
- X-ray - AP and lateral
Management of humeral shaft fracture
- Usually conservative with humeral brace
- Open reduction, internal fixation - open, vascular injury, plexus injury, forearm fracture (floating elbow), polytrauma
- Radial nerve palsy - only an indication for surgery if palsy occurs after an intervention or manipulation of the fracture
Which fracture is associated with radial nerve palsy?
Humeral shaft - especially middle and middle-distal parts
Transverse and spiral fractures more likely to be associated with radial nerve palsy than oblique and comminuted patterns of fracture
Radial head fracture mechanism of injury
Fall onto outstretched hand with pronated forearm
Injuries associated with radial head fracture
- Lateral collateral ligament injury (up to 80%)
- Medial collateral ligament injury
- Essex-Lopresti injury - radial head fracture, distal radioulnar joint injury, interosseus membrane injury
- Coronoid fracture
- Olecranon fracture
- Monteggia fracture/dislocation
- Scaphoid fracture
Classification of radial head fracture
Mason types 1-4
* Type 1 - non-displaced or minimally displaced (<2mm), no mechanical block to rotation
* Type II - displaced >2mm or angulated, possible mechanical block to forearm rotation
* Type III - comminuted and displaced, mechanical block to motion
* Type IV - radial head fracture with associated elbow dislocation
Things to look for in hand + wrist examination
- Scars - traumatic, carpal tunnel
- Swelling e.g. ganglions
- Skin colour - erythema, rashes
- Nails - pitting, onycholysis, nail fold infarction
- Muscle wasting - thenar, hypothenar and interosseous
- Skin thinning or bruising - steroids
- Psoriatic plaques
- Deformity - Z-thumb, swan neck, Boutonnieres, mallet finger, ulnar drift, clawed hand
- Elbows - psoriatic plaques, rheumatoid nodules
Hand and wrist examination - things to feel
- Temperature
- Radial and ulnar pulses
- Capillary refill time
- Thenar and hypothenar eminence muscle bulk
- Palmar thickening - Dupuytren’s
- Joint palpation - distal radio-ulnar joint, radio-carpal joint, thumb CMC, MCP, IPJ
- MCP joint squeeze
- Anatomical snuffbox - scaphoid fracture
- Radial nerve sensation - first dorsal webspace
- Median nerve sensation - thenar eminence
- Ulnar nerve sensation - hypothenar eminence
Movements for hand and wrist examination
Active
* Finger extension and flexion
* Finger abduction and adduction
* Wrist extension and flexion
* Pronation and supination
* Thumb flexion and extension
* Thumb abduction and adduction
* Pronation and supination
Passive if active reduced
Screening test for radial, ulnar and median nerve
* Wrist and finger extension against resistance - radial
* Index finger abduction against resistance - ulnar
* Thumb abduction against resistance - median
Special and function tests hand and wrist examination
- Power grip
- Pincer grip
- Pick up a small object
- Tinel’s test - tap over carpal tunnel, tingling/pain in distributation of median nerve = carpal tunnel syndrome
- Phalen’s test - wrist in forced flexion, tingling or pain in median nerve distribution = carpal tunnel syndrome
- Tinel’s test at elbow - tap over ulnar nerve behind medial epicondyle, tingling and pain over ulnar distribution = ulnar compression
Things to look for in elbow examination
- Cubitus valgus/varus
- Scars - operative or traumatic
- Bruising
- Swelling - effusion, inflammatory arthropathy, dislocation
- Muscle wasting
- Rheumatoid nodules
- Psoriatic plaques
- Popeye sign - ruptured biceps tendon
Feel - elbow examination
- Temperature
- Palpate joints - proximal radio-ulnar joint, ulno-trochlear joint, radial head, radiocapitellar joint, lateral (Tennis) and medial (Golfer) epicondyle of humerus, olcecranon
- Biceps tendon
- Bend to 90 degrees to look for effusion
Move - elbow examination
Active and passive
* Elbow flexion/extension
* Pronation/supination
* Feel for crepitus
Elbow examination special tests
- Medial epicondylitis (Golfer’s elbow) - active wrist flexion against resistance, palpate medial epicondyle
- Lateral epicondylitis (Tennis elbow) - active wrist extension against resistance, palpate lateral epicondyle
- Can hand reach mouth
Articulations of the scapula
- Glenohumeral joint - glenoid fossa of scapula and head of humerus
- Acromioclavicular joint - acromion of scapula and clavicle
Articulations of the humerus
- Glenohumeral joint - head of of the humerus with glenoid fossa of the scapula
- Elbow joint - capitulum articulates with head of the radius and trochlea articulates with the trochlear notch of the ulna
Articulations of the ulna
- Trochlear notch of ulna articulates with trochlea of humerus
- Proximal radio-ulnar joint - radial head and radial notch of ulna
- Distal radio-ulnar joint - distally the ulnar head articulates with the ulnar notch of the radius
Articulations of the radius
- Elbow joint - head of radius articulates with capitulum of the humerus
- Proximal radioulnar joint - radial head and radial notch of ulna
- Wrist joint - distal radius and carpal bones (scaphoid and lunate
- Distal radioulnar joint - articulation between ulnar notch and head of the ulna
List the bones of the hand
- Carpal bones (proximal) - 8
- Metacarpals - 5 (one per digit)
- Phalanges (distal) - three per finger (proximal, middle, distal), two per thumb (proximal and distal)
Describe the arrangement of the carpal bones
Proximal bones (lateral to medial)
* Scaphoid
* Lunate
* Triquetrum
* Pisiform
Distal bones (lateral to medial)
* Trapezium
* Trapezioid
* Capitate
* Hamate
List the rotator cuff muscles
- Supraspinatus
- Infraspinatus
- Teres minor
- Subscapularis
Describe the attachments of the rotator cuff muscles
- Supraspinatus - supraspinous fossa of the scapula to greater tubercle of the humerus
- Infraspinatus - infraspinous fossa of scapula to greater tubercle of humerus
- Subscapularis - subscapular fossa of scapula to lesser tubercle of humerus
- Teres minor - posterior surface of scapula to greater tubercle of humerus
Deltoid muscle attachments
Lateral third of the clavicle, acromion and spine of the scapula –> deltoid tuberosity on the lateral aspect of the humerus
Innervations of the deltoid muscle
Axillary nerve
Main actions of the deltoid muscle
Shoulder abduction - >15 degres
Shoulder flexion and extension
Shoulder medial and lateral rotation
Teres minor attachments
Posterior surface of the inferior angle of the scapula –> medial lip of the intertubercular groove of the humerus
Teres major actions
- Medial rotation
- Adduction
- Extension of flexed arm
Teres major innervation
Lower subscapular nerve
Supraspinatus actions
Abducts arm 0-15 degrees, assists deltoid beyond 15 to 90
Supraspinatus innervation
Subprascapular nerve
Infraspinatus actions
Lateral rotation
Infraspinatus innervation
Suprascapular nerve
Subscapularis actions
Medial rotation
Subscapularis innervation
Upper and lower subscapular nerves
Teres minor actions
Laterally rotates arm
Teres minor innervation
Axillary nerve
Pectoralis major attachments
- Clavicular head - anterior medial clavicle
- Sternocostal head - anterior surface of the sternum, superior six costal cartilages, aponeurosis of the external oblique muscle
- Distally - intertubercular sulcus of the humerus
Pectorialis major actions
Adducts and medially rotates arm
Draws scapula anteroinferiorly
Clavicular head - arm flexion
Innervation of the pectoralis major
Lateral and medial pectoral nerves
Pectoralis minor attachments
3rd-5th ribs, inserts into coracoid process of scapula
Pectoralis minor action
Stabilises scapula, draws it anteroinferiorly against thoracic wall
Pectoralis minor innervation
Medial pectoral nerve
Serratus anterior attachments
- Lateral aspects of ribs 1-8
- Attach to costal surface of the medial border of the scapula
Serratus anterior actions
Rotates scapula to allow arm to be raised above 90 degrees
Holds scapula against ribcage
Serratus anterior innervation
Long thoracic nerve
Subclavius muscle attachments
- Junction of 1st rib and its costal cartilage, inserts onto inferior surface and middle third of clavicle
Subclavius action
Anchors and depresses the clavicle
Subclavius innervation
Nerve to subclavius
What is the clinical impact of long thoracic nerve damage? What kind inuries can cause this?
Winged scapula - loss of serratus anterior muscle anchoring
Usually from traction injuries - upper limb stretched violently
Axillary lymph node clearance (e.g. breast cancer) can also cause
Borders of the axilla
- Apex - lateral border of 1st rib, superior border of scapula, posterior border of clavicle
- Lateral - intertubercular groove of the humerus
- Medial - serratus anterior and thoracic wall (ribs and intercostals)
- Anterior - pectoralis major, underlying pectoralis minor and subclavius muscles
- Posterior - subscapularis, teres major, latissimus dorsi
Contents of the axilla
- Axillary artery
- Axillary vein - cephalic and basilic veins drain into
- Brachial plexus
- Axillary lymph nodes
- Biceps brachii (short head) and coracobrachialis
List the extrinsic muscles of the shoulder/superficial back muscles
Superficial
* Trapezius
* Latissimus dorsi
Deep
* Levator scapulae
* Rhomboid major
* Rhomboid minor
Trapezius attachments, actions, innervation
- Attachments - skull, nuchal ligament, spinous processes of C7-T12 –> clavicle, acromion, scapula spine
- Actions - upper fibres elevate and rotate scapula during abduction of arm, middle fibres retract scapula, lower fibres pull scapula inferiorly
- Innervation - accesory nerve, proprioception from C3/4
Latissimus dorsi attachments, actions, innervation
- Atachments - spinous processes of T7-T12, iliac crest, thoracolumbar fasci and inferior three ribs –> intertubercular sulcas of humerus
- Actions - extends, adducts and medially rotates arms
- Innervation - thoracodorsal nerve
Levator scapulae attachments, actions, innervation
- Attachments - transverse processes of C1-4 –> medial border of scapula
- Actions - elevates scapula
- Innervation - dorsal scapular nerve
Rhomboid major attachments, actions, innervation
- Attachments - spinous processes T2-5 –> medial border of scapula
- Actions - retracts and rotates scapula
- Innervation - dorsal scapular nerve
Rhomboid minor attachments, actions, innervation
- Attachments - spinous processes C7-T1, attaches to medial border of scapula at level of spine of scapula
- Actions - retracts and rotates the scapula
- Innervation - dorsal scapular nerve
List the muscles of the upper arm and describe their innervation and blood supply
Anterior compartment
* Muscles - biceps brachii, brachialis, coracobrachialis
* Innervation - musculocutaneous nerve
* Blood supply - brachial artery
Posterior compartment - triceps brachii
* Innervation - radial nerve
* Blood supply - profunda brachii artery
Biceps brachii attachments and function
- Attachments - long head from supraglenoid tubercule of scapula, short head from coracoid process of the scapula –> radial tuberosity and fascia of forearm via bicipital aponeurosis
- Function - supination, flexion at elbow and shoulder
Which spinal nerve does the biceps tendon reflex test?
C6
Coracobrachialis attachments and function
- Coracoid process of scapula –> medial humerus shaft
- Function - flexion of arm at shoulder, weak adduction
Brachialis attachments and function
- Medial/lateral humeral shaft –> ulnar tuberosity
- Function - flexion at elbow
Triceps brachii attachments and function
- Long head from infraglenoid tubercle
- Lateral head from humerus, superior to radial groove
- Medial head from humerus, inferior to radial groove
- Converge and insert into olecranon of ulna
Which spinal nerve is tested by the triceps reflex?
C7
List the muscles of the anterior compartment of the forearm and describe their action and innervation
- Superficial - flexor carpi ulnaris, palmaris longus, flexor carpi radialis, pronator teres
- Intermediate - flexor digitorum superficialis
- Deep - flexor pollicis longus, flexor digitorum profundus, pronator quadratus
Pronation, flexion of wrist and fingers
Innervated by median nerve except flexor carpi ulnaris, medial half of flexor digitorum profundus (ulnar nerve)
List the muscles of the posterior compartment of the forearm, describe their action and innervation
- Superficial - brachioradialis, extensor carpi radialis longus and brevis, extensor digitorum communis, extensor digiti minimi, extensor carpi ulnaris, anconeus
- Deep - supinator, abductor pollicis longus, extensor pollicis brevis, extenor pollicis longus, extensor indicis
Generally - extension of wist and fingers
* Brachioradialis - flexion at elbow
* Abduction/adduction of wrist/thumb
* Supination
All innervated by the radial nerve
What causes wrist drop?
Damage to the radial nerve proximal to the elbow - loss of extensor muscle innervation
* Axilla - humeral dislocations or fractures of the proximal humeus
* Radial groove of humerus - humeral shaft fracture
What is the origin point of the muscles of the posterior compartment of the forearm vs anterior compartment of the forearm?
Posterior compartment - lateral epicondyle of the humerus
Anterior compartment - medial epicondyle of the humerus
List the instrinsic muscles of the hands and describe their innervation and actions
(Action of those whose names don’t describe them)
- Thenar muscles - opponens pollicis, abductor pollicis brevis, flexor pollicis brevis (median nerve)
- Hypothenar muscles - opponens digiti minimi, abductor digiti minimi, flexor digiti minimi brevis (ulnar nerve)
- Lumbricals - flexion at MCP, extension at IP joints, lateral two lumricals innervated by median nerve, medial two lumbricals innervated by ulnar nerve
- Interossei - dosal and palmar (dorsal do abduction, palmar do adduction), both innervated by ulnar nerve
- Palmaris brevis - grip (ulnar nerve)
- Adductor pollicis - adducts thumb (ulnar nerve)
Describe the blood supply to the arm
- Subclavian artery –> axillary artery –> brachial artery –> radial and ulnar arteries –> superficial and deep palmar arches
- Superficial veins - cephalic vein + basilic vein (connected by median cubital vein) –> axillary vein –> subclavian vein
- Deep veins - ulnar veins + radial veins –> brachial vein –> axillary vein –> subclavian vein
Shoulder examination - look
- Scars - operative / traumatic
- Asymmetry
- Swelling
- Muscle wasting - deltoid, trapezius, supraspinatus, infraspinatus
- Winged scapula - push hands against wall
Shoulder examination - feel
- Temperature
- Palpate joints - sternoclavicular joint, clavicle, acromioclavicular joint, acromion, coracoid process, head of humerus, greater and lesser tubercle of humerus, spine of scapula
Shoulder examination - move
Compound movements (screening)
* Arms behind head - external rotation and abduction
* Arms behind back, reach up - internal rotation an adduction
Active movement
* Shoulder flexion/extension
* Shoulder abduction/adduction
* Internal rotation
* External rotation
* Abduct and palpate scapula for smoothness of scapular movement
Passive movement - feel for crepitus
Shoulder examination - special tests
Supraspinatus
* Supraspinatus assessment (empty can test/Jobe’s test) - abduct to 90 degrees, angle forwards at 30 degrees, point thumb to floor, push down on arm (abduction against resistance)
* Impingement - painful arc, pasively move to maximum abduction, pain from 60-120 degrees
Infraspinatus/teres minor
* External rotation against resistance
* External rotation in abduction - 90 degree abduction, bend elbow to 90 degress, passively externally rotate shoulder (inability to maintain = Hornblower’s sign)
Subscapularis
* Internal rotation against resistance - hand behind back, press against hand while lifting off back
Acromioclavicular joint
* Scarf test - flex shoulder to 90, place hand on contralateral shoulder, apply resistance to elbow in contralateral direction
Hip examination - look
- Scars
- Swelling
- Asymmetry
- Quadriceps, gluteal wasting
- Leg length discrepancy
- Pelvic tilt
- Flexion abnormalities
- Gait - ROM, limping, leg length, turning, waddling, Trendelenburg’s gait
Hip examination - feel
- Temperature
- Palpate joint - greater trochanter
- Leg length assessment - apparent (umbilicus to medial malleolus), true (ASIS to medial malleolus)
Hip examination - move
Active
* Flexion
* Extension
Passive
* Flexion
* Internal rotation
* External rotation
* Abduction
* Adduction
* Extension
Hip examination - special tests
- Thomas’s test - for fixed flexion deformity, lie flat with hand under lumbar spine, passively flex other hip and observe contralateral hip
DON’T DO IF HAVE HIP REPLACEMENT - DISLOCATION RISK) - Trendelenburg’s test - for hip abductor weakness, stand with hands on shoulders, fingers on iliac crests, stand on one leg and observe for lateral pelvic tilt
Knee examination - look
- Scars
- Swelling
- Psoriasis plaques
- Valgus (apex medial) or varus (apex lateral)
- Quadriceps wasting
- Hyperextension or fixed flexion deformity
- Popliteal swellings
- Patellar position
- Gait - ROM, limping, leg length, turning, high stepping
Knee examination - feel
- Temperature
- Measure quadriceps bulk
- Palpation of extended knee - patella, patellar ligament, medial and lateral joint lines
- Assess for effusion - patellar tap, sweep test
- Palpation of flexed knee - patella, patellar ligament, medial and lateral joint lines, tibial tuberosity, popliteal fossa
Knee examination - move
Active
* Flexion
* Extension
Passive
* Flexion
* Extension
Knee examination - special tests
Cruciate ligament assessment
* Posterior sag sign - PCL
* Anterior drawer test - ACL
* Posterior drawer test - PCL
* Lachman’s test - ACL
Collateral ligament assessment
* Varus stress test - LCL
* Valgus stress test - MCL
* Can repeat if stable with knee flexed to 30 degrees
Mensci assessment
* McMurray’s test - medial meniscus, lateral meniscus
Foot and ankle examination - look
- Gait - ROM, limping, leg length, turning, height of steps
- Scars
- Swelling
- Psoriasis plaques
- Fixed flexion deformity of toes
- Big toe misalignment
- Calluses
- Foot arch
- Heel - valgus or varus
- Muscle wasting
- Achilles tendon
Ankle and foot examination - feel
- Temperature
- Pulses - posterior tibial, dorsalis pedis
- MCP joint squeeze
- Ankle and foot palpation - metatarsal and tarsal bones, tasral joint, ankle joint, subtalar joint, calcaneum, medial/lateral malleoli, distal fibula
- Achilles tendon and gastrocnemius
Ankle and foot examination - move
Active + passive
* Plantarflexion
* Dorsiflexion
* Toe flexion
* Toe extension
* Ankle/foot inversion
* Ankle/foot eversion
Passive only
* Subtalar joint
* Midtarsal joint
Ankle and foot examination - special tests
- Simmonds’ test - achilles tendon rupture
Spine examination - look
- Scars
- Muscle wasting
- Scoliosis
- Asymmetry
- Pelvic tilt
- Gait - ROM, limping, leg length, turning, Trendeleburg’s gait, waddling gait
Spine examination - feel
- Spinal processes and sacroiliac joints
- Paraspinal muscles
Spine examination - move
- Cervical spine - flexion, extension, lateral flexion, rotation
- Lumbar spine - flexion, extension, lateral flexion
- Thoracic spine - rotation
Spine examination - special tests
- Schober’s test - 5cm below PSIS, 10cm above, should increase to >20cm
- Sciatic stretch test - straight leg raise
- Femoral nerve stretch test
Complications of septic arthritis
- Osteoarthritis
- Osteomyelitis
- Osteonecrosis
- Sepsis
Define neuropraxia
- Mildest form of traumatic peripheral nerve injury
- Focal segmental demyelination at site of injury without disruption of axon continuity
What causes neuropraxia?
Usually due to blunt injury - external blow, causes:
* Compression
* Ischaemia
* Inflammation
What signs/symptoms does neuropraxia cause?
- Motor/sensation deficit
- Numbness/tingling/burning
- Flaccid paralysis of muscles innervated by injured nerves/nerve
- Transient symptoms - usualy resolve days-weeks after injury
Define axonotmesis
- More severe than neuropraxia, less than neurotmesis
- Damage to axons and myelin sheath, endoneurium, perineurium and epineurium intact
What causes axonotmesis?
- More severe injury than neuropraxia - crush or sretch usually
Classification of peripheral nerve injuries
Seddon’s/Sunderland’s classification
First degree (class I)
* Neurapraxia - temporary interruption of conduction without loss of axonal continuity
* No Wallerian degeneration
* Full recovery within days to weeks
Second degree (class II)
* Axonotmesis - loss of relative continuity of axon and myelin, preservation of connective tissue framework of nerve
* Wallerian degeneration distal to site of injury
* Recovery possible without surgical treatment, although sometimes required
Third degree (class III)
* Neurotmesis - endoneurium lesion, epineurium and perineurium intact
* Wallerian degeneration distal to injury
* Surgical intervention often necessary
Fourth degree (class III)
* Same as third degree but only epineurium remain intact
* Surgical intervention necessary
Fifth-degree (class III)
* Same as third degree but complete transection of nerve
* No recovery without surgical treatment
Define Wallerian degeneration
Degeneration of the axon distal to an injury when nerve fibre is cut or crushed
Define neurotmesis
Nerve and nerve sheath severed
Signs and symptoms of neurotmesis
- Pain
- Dysesthesias
- Complete loss of sensory and motor function of the affected nerve
Describe a hemiplegic gait and list causes
- Hemiplegia = spastic flexion of the upper limb and extension of the lower limb, extended leg is elongated so patients have to circumduct leg to prevent foot from dragging on ground
- Caused by lesion in the CNS, resulting in unilateral weakness and spasticity
Causes
* Unilateral cerebral lesion - stroke, space-occupying lesion, trauma, multiple sclerosis
* Hemisection of the spinal cord - trauma
Clinical features associated with hemiplegic gait
- Increased tone ith clasp knife spasitcity
- Hyperreflexia withor without clonus
- Upgoing plantars i.e. positive Babinski
- Reduced power
- Sensory deficit - pattern of sensory loss depends on the site of the lesion in the nervous system
Define diplegic gait
- Similar to hemiplegic gait but bilateral in nature
- Spasticity worse in lower limbs compared with upper limb
- Hips and knees flexed and abducted and ankles are extended and internally rotated
- Knees forced together due to spasticity in adductor muscles resulting in leg overlap when walking (scissoring)
- Circumduction of both legs during swing phase
- Upper limb may have flexor posturing of the elbows and wrist with shoulders and fingers in adduction
- Lack swinging movements present in normal gait
Clinical features associated with biplegic gait
- Increased tone with clasp-knife spasticity
- Hyperreflexia with or without clonus
- Upgoing plantars (i.e. positive Babinski)
- Reduced power
- Sensory deficit – if a diplegic gait is caused by spinal cord pathology, the ‘sensory level’ (ie. the lowest dermatome level with normal sensation) correlates with the level of spinal cord pathology
- Wasting and fasciculations (consider motor neuron disease)
Causes of biplegic gait
Spinal cord lesion (sensation usually affected):
* Prolapsed intervertebral disc
* Spinal spondylosis
* Spinal tumour
* Transverse myelitis
* Spinal infarct
* Syringomyelia
* Hereditary spastic paraparesis
Bilateral brain lesion:
* Cerebral palsy
* Multiple sclerosis
* Bilateral brain infarcts
* Midline tumour (e.g. paraspinal meningioma)
* Motor neuron disease: associated with lower motor neuron findings
Describe the features of a Parkinsonian gait
- Initiation: typically slow to start walking due to failure of gait ignition and hesitancy.
- Step length: reduced stride length with short steps is common (shuffling gait). Each step may get progressively smaller as the patient attempts to retain balance (known as festinant gait).
- Arm swing: reduced arm swing on one or both sides (often an early feature of Parkinson’s disease).
- Posture: flexed trunk and neck causing a stooped appearance.
- Tremor: resting tremor can be observed when the patient is distracted by walking.
- Turning: impaired balance on turning or hesitancy is common due to postural instability.Initiation: typically slow to start walking due to failure of gait ignition and hesitancy.
Clinical features associated with Parkinsonian gait
Tremor
Rigidity
Bradykinesia
Hypomimia
Causes of Parkinsonian gait
- Idiopathic Parkinson’s disease
- Vascular Parkinson’s disease
- Dementia with Lewy bodies
- Parkinson’s plus syndromes (e.g. multisystem atrophy and progressive supranuclear palsy)
- Drug-induced Parkinsonism (e.g. antipsychotics, antiemetics)
- Dementia pugilistica
Describe an ataxic gait
- Stance: a broad-based ataxic gait is typically associated with midline cerebellar pathology (e.g. a lesion in multiple sclerosis or degeneration of the cerebellar vermis secondary to chronic alcohol excess).
- Stability: a staggering, slow and unsteady gait is typical of cerebellar pathology. In unilateral cerebellar disease, patients will veer towards the side of the lesion.
- Turning: patients with cerebellar disease will find the turning manoeuvre particularly difficult.
Clinical features associated with ataxic gait
Clinical features associated with cerebellar ataxia:
* Nystagmus
* Ataxic dysarthria
* Dysmetria
* Intention tremor
* Dysdiadokokinesia
Clinical features associated with sensory ataxia:
* Positive Romberg’s sign
* Impaired proprioception
* Impaired vibration sensation
* Absence of other cerebellar signs (e.g. dysmetria, nystagmus, dysarthria)
Clinical features associated with vestibular ataxia:
* Vertigo
* Nausea
* Vomiting
Causes of ataxic gait
Cerebellar ataxia:
* Cerebellar stroke (ischaemic or haemorrhagic)
* Space-occupying lesion
* Multiple sclerosis
* Alcoholism
* B12 deficiency
* Drugs (e.g. phenytoin, carbamazepine, barbiturates, lithium)
* Genetic disease (e.g. Frederich’s ataxia, spinocerebellar ataxia)
* Paraneoplastic disease
Sensory ataxia:
* Peripheral neuropathy (e.g. diabetes mellitus)
*
Vestibular ataxia:
* Labyrinthitis
* Meniere’s disease
* Acoustic neuroma
Describe a neuropathic gait
- Weakness of the dorsiflexors of the foot
- Causes foot drop and dragging of the toes during the swing stage
- To prevent toes dragging on the floor, knee and hip flex excessively, creating a ‘high stepping’ gait
Clinical features associated with neuropathic gait
Peripheral vascular disease
Peripheral sensory impairment
Distal muscle weakness
Reduced or absent reflexes
Causes of foot drop
- Isolated common peroneal nerve palsy (e.g. secondary to trauma or compression)
- L5 radiculopathy (e.g. disc prolapse)
- Generalized polyneuropathy involving multiple nerves (e.g. diabetic neuropathy, motor neurone disease, Charcot-Marie Tooth disease)
Describe a myopathic gait
Hip abductor weakness results in an inability to stabilize the pelvis during the stance phase. As a result, the pelvis tilts downwards towards the unsupported side during the swing phase of the gait cycle.
The body compensates to prevent the swinging foot from dragging by:
* Laterally flexing the torso away from the leg in swing phase; this draws the pelvis and leg up off the floor (causing the characteristic ‘waddling’ appearance)
* Circumducting the leg
Clinical features associated with myopathic gait
- Difficulty standing from a seated position without the use of the arms
- Difficulty standing from a squat or sitting up from a lying position
- Positive Trendelenburg’s sign; when the patient stands on one leg, the pelvis drops towards the contralateral side
Causes of myopathic gait
Systemic disease:
* Hyperthyroidism
* Hypothyroidism
* Cushing’s syndrome
* Acromegaly
* Polymyalgia rheumatica
* Polymyositis
* Dermatomyositis
Muscular dystrophies:
* Duchenne’s muscular dystrophy
* Becker’s muscular dystrophy
* Myotonic dystrophy
Describe a choreiform gait
Involuntary movements such as:
* Oro-facial dyskinesia (grimacing or lip-smacking)
* Choreic movements of the upper and lower limbs (writhing, dance like semi-purposeful movements)
The involuntary movements are usually present at rest, however, walking can accentuate the movements.
Causes of choreiform gait
Basal ganglia disease:
* Huntington’s disease
* Sydenham’s chorea
* Cerebral palsy (choreiform type)
* Wilson’s disease
* Dopaminergic medications (e.g. Parkinson’s medications)
Describe an antalgic gait
- Abnormal gait pattern which develops as a result of pain
- Typically the stance phase is reduced on the affected leg resulting in a limping appearance
Causes of antalgic gait
Any cause of lower limb pain such as:
* Osteoarthritis
* Inflammatory joint disease
* Lower limb fracture
* Nerve entrapment (e.g. sciatica)
List the common causes of an abnormal gait
- Lower limb pain - osteoarthrtitis, inflammatory joint disease etc.
- Neurological disease - Parkinson’s, peripheral neuropathy, stroke etc.
Define compartment syndrome
Critical pressure increase within a confined compartmental space, intra-compartmental pressure in a fascial compartment becomes elevated beyond the capillary perfusion pressure
Most common sites of compartment syndrome
Can be any but most commonly leg, thigh, forearm, foot, hand and buttock
Describe the aetiology/pathophysiology of compartment syndrome
- Typically occurs follwing high energy trauma, crush injuries or fractures that cause vascular injury
- Other causes - iatrogenic vascular injury, tight casts//splints, DVT, post-reperfusion swelling
- Fascial compartments are enclosed by a tough fascia which is resistant to expansion, any swelling or fluid accumulated will increase the intra-compartmental pressure
- As pressure increases, veins are compressed, increasing hydrostatic pressure which pushes fluid out of veins and into the compartment, increasing the pressure further
- Traversing nerves are compressed, causing a sensory +/- motor deficit in the distal distribution (paraesthesia)
- As intra-compartmental pressure reaches the diastolic pressure, the arterial inflow will be compromised and the limb will become ischaemic
Risk factors for compartment syndrome
- Major surgical procedures (e.g. orthopaedic repair, post-embolectomy, post-laparotomy)
- Blunt trauma
- Burns
- Reperfusion injury
- Crush injury
- Fractures: closed or open
- Tight casts
- Ongoing intra-abdominal bleeding
- Penetrating trauma (e.g. vascular injury)
- Malignancy
Describe the clinical features of compartment syndrome
- Syptoms usually within hours but can present up to 48 hours post-insult
- Most reliable symptom is severe pain, disproportionate to injury, not relieved by initial measures
- Pain worse with passively stretching of muscle across fascial compartment
- Compartment feels tense (but not generally swollen - not able to extend)
- Paraesthesia - evolving neurology
- Can progress to acute limb ischaemia - pain, pallor, perishingly cold, paralysis, pulselessness (pulse can be present even at late stages)
What initial measures can be used to identify if pain is due to compartment syndrome?
Analgesia e.g. IV morphine
Elevation of limb to level of heart
Removal of any tight bangaes/dressings/casts
If pain persists after 30 minutes - highly suggestive of compartment syndrome
How is compartment syndrome diagnosed?
- Usually diagnosed clinically
- Can use intra-compartmental pressure monitoring - especialluy useful in nconscious patients/those with nerve blocks
- <30mmHg difference between diastolic BP and compartment pressure - increased risk of compartment syndrome
- Intra-compartment pressure of >40mmHg with clinical signs is diagnostic of acute compartment syndrome
- Creatinine kinase trending upwards may aid diagnosis
How is compartment sydrome managed?
- Initial management - remove external dressings/bandages/casts, IV analgesia, maintain blood pressure (IV fluids)
- Urgent fasciotomy is definitive management
- Leave incisions open for 24-48 hours, then debride any dead tissue and close wounds (leave subtending fascia open)
- Monitor renal function closely due to potential rhabdomyolysis or reperfusion injury - IV fluids
List the complications associated with acute compartment syndrome
- Irreversible neuroascular damage to affected limb
- Rhabdomyolysis, reperfusion injury - renal impairment
- Muscle/joint contracture e.g. Volkmann’s contracture
- Infection
- Amputation
- Long term disability
Describe chronic compartment syndrome
- Associated with exertion, during which pressure in compartment rises, blood flow to compartment is restricted and symptoms start
- Resolves during rest
- Symptoms - pain, numbness, paraesthesia
- Needle manometry can be used to measure pressure increase during exertion
- May require faciotomy to treat
List the compartments of the lower leg
- Anterior
- Lateral
- Superficial posterior
- Deep posterior
List the compartmets of the thigh
- Anterior
- Medial
- Posterior
List the compartments of the forearm
Superficial volar compartment
Deep volar compartment
Dorsal compartment
Mobile wad compartment
List the regions of the vertebral column and the number of vertebrae in each region
- Cervical - 7
- Thoracic - 12
- Lumbar - 5
- Sacrum 5 (fused)
- Coccyx - 4 (fused)
At what level does the spinal cord terminate? What lies in the inferior part of the spinal column?
- Terminates at level of L2, region called conus medillaris, continues as filum terminale which anchors the spinal cord to the coccyx
- Cauda equina is a collection of nerves inferior to the conus medillaris that continue to travel through the vertebral collum to the coccyx
Where is the cauda equina located?
Occupies the lumbar cistern, a subarachnoid space inferior to the conus medullaris
Surrounded by CSF
Begins at vertebral level of L1
Which nerves make up the cauda equina? What do they innervate?
- L2-L5
- S1-S5
- Coccygeal nerve
- Innervation of pelvic organs, motor innervation of hips, knees, ankles, feet, internal and externalanal sphincter, sensory innervation of the perineum, parasympatheitc innervation of the bladder
What is the most common cause of cauda equina syndrome?
List the other causes.
- Central disc prolapse/herniation - L5/S1 and L4/5 most common
- Trauma - vertebral fractures or subluxation
- Malignancy - primary or metastatic
- Spinal infection - abscess, meningitis, tuberculosis/Pott’s disease, discitis
- Inflammation - ankylosing spondylitis
- Iatrogenic - spinal anaesthesia, post-operative haematoma, manipulation
Describe the presentation of cauda equina syndrome
- Lower motor neurone signs and symptoms
- Reduced lower limb sensation (often bilateral) - including saddle anaesthesia
- Bladder/bowel dysfunction - retention, incontinence, reduced anal tone
- Lower limb motor weakness
- Lower limb hyporeflexia
- Severe back pain
- Impotence
Investigations for suspected cauda equina syndrome
Urgent lumbar-sacral MRI spine
Pre- and post-voiding bladder scan looking for retention and incomplete bladder empyting
Classification of cauda equina syndrome
- Cauda equina syndrome with retention - back pain with unilateral or bilateral sciatica, lower limb motor weakness, sensory disturbance in the saddle region, loss of anal tone and loss of urinary control
- Incomplete cauda equina syndrome - as above, only altered urinary sensation (e.g. loss of desire to void, diminshed sensation, poor stream, need to strain), painful retention may precede painless retention in some cases
- Suspected cauda equina syndrome - severe back and leg pains with neurological symptoms and signs and a suggestion of sphincter disturbance
Most will progress to complete compression if untreated
What is the differential diagnosis of cauda equina syndrome?
Radiculopathy – presents with radiating back pain, however there will be no faecal, urinary, or sexual dysfunction in these patients
Cord compression – a surgical emergency with a similar pathophysiology to CES, however is characterised by upper motor neurone signs
Muscloskeletal pain – relating to strain of paraspinal muscles, with severe pain that may lead to limited movement, but no other focal neurological signs
How is cauda equina syndrome managed?
- Adequate analgesia, catheter if urinary retention
- Urgent surgical decompression within 24 hours of symptom onset - laminectomy +/- discectomy
- Radiotherapy/chemotherapy may be used if malignant cause
Complications of cauda equina syndrome
Paraplegia
Lower limb numbness
Chronic urinary retention or incontinence
Chronic sexual dysfunction
How should a patient involved in major trauma be assessed?
(C)ABCDE
Catastrophic haemorrhage
Airway (with c-spine protection)
Breathing
Circulation
Disability
Exposure
How should the cervical spine be assessed in major trauma?
High risk criteria - requires imaging and immobilisation
* Age 65 or older
* Dangerous mechanism of injury (fall from over one metre or down five or more steps, or an axial loading injury)
* Paraesthesia in any limb(s)
Low risk - none of the high risk criteria, one or more of
* Involved in a minor rear-end motor vehicle collision
* Comfortable sitting
* Ambulatory since the injury
* No midline cervical spine tenderness
* Delayed onset of neck pain
Low risk doesn’t require imaging/immobilsation unless can’t rotate head 45 degrees to left and right
List the life-threatening chest injuries
TOM CAT
Tension pneumothorax
Open pneumothorax
Massive haemothorax
Cardiac tamponade
Airway injury
Tracheobronchial injury
Where can blood be lost from?
- On the floor - external wound
- Chest cavity
- Abdominal cavity
- Pelvis
- Long bones
What is the lethal triad in major haemorrhage? How can this be avoided?
Hypothermia: keep warm with blankets, warmed air, use a blood warmer to give blood, and when examining the patient, limit their exposure to the minimum necessary
Acidosis: maximise oxygenation and treat/prevent hypoventilation to prevent respiratory acidosis. Avoid giving crystalloids as this can exacerbate acidosis.
Coagulopathy: avoid crystalloids or unbalanced blood products as they can cause dilutional coagulopathy. Permissive hypotension (aiming for a target systolic of 80-100mmHg) can be used to avoid excessive fluid administration and prevent dilutional coagulopathy.
What symptoms are suggestive of cardiac tamponade?
Beck’s triad
* Jugular venous distension
* Quiet heart sounds
* Hypotension
How is a secondary survey performed?
- After all life-threatening injuries have been identified and addressed
- History (AMPLE) - allergies, medication, PMH including tetanus status, last meal, events leading to injury
- Head-to-toe examination - head and face, neck, chest, abdomen, limbs, back , buttocks and perineum, genitalia
Describe the immediate resuscitation of a trauma patient
C - catastrophic haemorrhage
* Direct pressure, haemostatic dressing, touniquets
A - airway
* Definitive airway if patient cannot support own airway or will not be able to - rapid sequence induction of anaesthesia and intubation
* May require surgical airway via surgical cricothyroidotomy
* While awaiting definitive airway can due jaw thrust to support airway (avoid head-tilt chin-lift due to risk of c-spine injury or nasopharyngeal airway due to risk of basal skull fracture)
C-spine
* Immobilise with hard collar or head blocks
B - breathing
* Oxygen
* Treat e.g. tension pneumothorax, haemothorax
C - circulation
* Pharmacological - tranexamic acid, reverse antigcoagulation
* Cannulation
* Blood tests - FBC, U&Es, LFTs, coagulation screen, group + save, toxicology screen, lactate
* Blood product transfusion - 1:1:1 packed red cells, fresh frozen plasma, platelets
* ECG
D - disability
* CT head
* Raised ICP - IV mannitol, hypertonic saline
* Surgical intervention?
E - exposure
* Analgesia
* Wound care
* Fractures
List the types of shock and causes of each
- Septic shock - bacterial infections e.g. appendicitis, pneumonia, necrotising fasciitis
- Haemorrhagic shock - blood loss
- Neurogenic shock - high level spinal cord transection
- Cardiogenic shock - ischaemic heart disease, myocardial trauma/contusion
- Anaphylactic shock
Stages of haemorrhagic shock
Describe the pathophysiology of the formation of fat emboli
Mechanical theory – Fatty tissue is directly released into the vascular circulation as a result of trauma
Biochemical theory – Inflammatory response to the trauma causes release of free fatty acids into the venous system from the bone marrow
Causes
* Acute long bone fractures
* Intramedullary instrumentation - intramedullary nailing, hip/knee arthroplasty
Define fat embolism syndrome
Systemic manifestations of fat emboli within the microcirculation
Describe the clinical presentation of fat embolism syndrome
- Usually following trauma
- Worsening shortness of breath
- Confusion
- Drowsiness
- Petechial rash
- Signs - tachypnoea, tachycardia, hypoxia, confusion, low-grade pyrexia
Describe the diagnostic criteria for fat embolism syndrome
Gurd’s criteria can be used for the diagnostic aid for fat embolism syndrome. The presence of 2 Major or 1 Major + 4 Minor criteria is deemed diagnostic
Major criteria = Petechial Rash, Respiratory Insufficiency, Cerebral Involvement
Minor criteria = Tachycardia, Pyrexial, Retinal Changes, Jaundice Thrombocytopaenia, Anaemia, Raised ESR, Fat macroglobulinaemia
Which investigations should be done in suspected fat embolism syndrome. What findings are suggestive of FES?
- Routine bloods, including FBC, CRP, U&Es, LFTs, and a clotting screen
- ABG - type 1 respiratory failure
- Blood film may show the presence of fat globules
- CXR will classically show diffuse bilateral pulmonary infiltrates
- CTPA scan - ground-glass changes with a global distribution
How is fat embolism syndrome managed?
- Supportive
- Often requires mechanical ventilation
How can fat embolism syndrome be prevented?
- Early fracture stabilisation (within 24 hours) of long bone fracture
- Close monitoring - pulse oximetry
How should the c-spine be immobilised during intubation?
Manual in-line stabilisation
Describe this X-ray
Transverse fracture through the proximal humerus (surgical neck of humerus) with displacement of the distal component
Describe this X-ray
A transverse, comminuted fracture of the surgical neck of humerus is accompanied by a fracture line separating the greater tubercle from the rest of the humeral head
Describe this X-ray
- Dislocation of the right acromioclavicular joint, with the clavicle displaced superiorly
- Widening of the coracoclavicular distance - 23mm
Describe this X-ray
AP view of the shoulder
Humeral head is dislocated from the glenoid of the scapula and is now inferior to the coracoid of the scapula - anterior dislocation
Describe this X-ray
Shoulder AP
The glenohumeral joint is widened and the humeral head has taken on a more rounded ‘light bulb’ shape
= posterior glenohumeral dislocation
Classification system used for ACJ joints
Rockwood classification
* Type 1 - clavicle not elevated above acromion
* Type II - clavicle elevated but not above superior border of acromion
* Type III - clavicle elevated above superior border of acromion but coracoclavicular distance less than twice normal (<25)
* Type IV - clavicle displaced posterior into trapezius
* Type V - clavicle markedly elevated and coracoclavicular distance more than double normal (>25mm)
* Type VI- clavicle inferiorly displaced behind coracobrachialis and biceps tendons - rare
Describe the stabilisers of the elbow
- Primary static stsabilisers - humeroulnar joint and medial and collateral ligaments
- Secondary static stabilisers - radiocapitellar joint, joint capsule, common flexor and extensor origin tendons
- Dynamic stabilisers - anconeus, brachialis, triceps brachii muscles
Clinical presentation of elbow dislocations
- Typically present following a high-energy fall
- The joint will be painful and deformed, with associated swelling and decreased function (usually near immobile in near full extension with disruption of the equilateral triangle of the elbow)
Which nerve is commonly injured due to elbow dislocation? What symptoms does this cause?
Ulnar nerve
* Pain/numbness/tingling on ulnar side of arm/hand
* Claw-like deformity - hyperextension at MCP and flexion at proximal and distal IP of 4th and 5th fingers
* Reduced finger abduction
Which muscles, joints and nerves are involved in:
* Claw hand deformity
* Hand of Benediction deformity
* Wrist drop?
When is the deformity seen?
- Medial lumbricals, DIP and PIP flexion, MCP extension, ulnar nerve
- Flexor digitorum profundus and superficialis, flexor pollicis longus and brevis, MCP, DIP and PIP extension, median nerve
- Extensor muscles (extensor carpi ulnaris, extensor digiti minimi, extensor digitorum, extensor indicis, extensor carpi radialis brevis, extensor carpi radialis longus), wrist joint, radial nerve
Claw hand - when extending fingers
Hand of Benediction - when flexing fingers
Wrist drop - when extending wrist
What is the most common type of elbow dislocation?
Posterolateral
Which age group are elbow dislocations most commonly seen in?
10-20 years old
Describe the mechanism of injury of elbow dislocations
Typically - axial loading, supination and valgus force
How should a vascular examination be carried out in patients with an elbow dislocation?
Capillary refill - good capillary refill can be found even in those with an arterial injury, due to the elbow having a rich collateral circulation
Pulse - any concern over the pulse of the limb will warrant a Doppler ultrasound for further assessment
How are elbow dislocations classified?
- Anatomical location of olecranon in relation to the humerus
- Simple vs complex - simple has no associated fracture, complex has associated fracture
What is a terrible triad injury? Why is it terrible?
- Elbow dislocation associated with a LUCL tear, radial head fracture, and coronoid tip fracture
- Causes very unstable elbow and is associated with a poor outcome
- Likely to have recurrent problems with instability, stiffness, and arthrosis
Investigations for elbow dislocation
X-rays - AP and lateral (loss of the radiocapitellar and ulnotrochlea congruence)
CT only if associated fractures
Management of elbow dislocation
Closed vs open reduction +/- ORIF and soft tissue repair (if fracture)
Closed reduction
* Requires sufficient analgesia/sedation
* In-line traction or manipulation of the olecranon (in distal and anterior direction)
* Elbow then flexed to 90 degrees with back slab
* X-ray to confirm reduction
* Neurovascular status re-assessed and documented
* If the lateral collateral ligament is damaged the elbow will be more stable in pronation, if the medial collateral ligament is disrupted the elbow will be more stable in supination
Initially immobilisation then rehabilitation
Which complications are associated with elbow dislocations?
- Early stiffness with loss of terminal extension
- Ulnar nerve stretch injury
- Recurrent instability - reuccrence rate low (<2%)
- Heterotophic ossification
What is the most common mechanism of injury of a radial head fracture?
Fall on an outstretched hand
What soft tissue injuries are associated with radial head fractures?
Ligament injury
* Lateral collateral ligament (LCL) injury most common (up to 80% on MRI)
* Medial collateral ligament (MCL) injury
Essex-Lopresti injury
* Radial head fracture
* Distal radioulnar joint (DRUJ) injury
* Interosseus membrane injury
What does this X-ray show?
Lateral view of elbow/forearm
Monteggia fracture/dislocation - proximal 1/3 ulnar fracture and anterior radial head dislocation (type 1)
What does this X-ray show?
Lateral view of forearm/wrist
Galeazzi fracture/dislocation - distal 1/3 radial fracture and dorsal dislocation of distal ulna (type I)
What does this X-ray show?
Transverse fracture through the proximal humerus with displacement of the distal component - surgical neck fracture
What does this X-ray show?
A transverse fracture of the surgical neck of humerus is accompanied by a fracture line separating the greater tubercle from the rest of the humeral head. Comminuted fracture.
What does this X-ray show?
Oblique fracture of the humerus shaft
Distal component is markedly displaced
What does this X-ray show?
Trasverse fracture of the distal radius
Dorsal angulation and displacement
Shortening creating a very narrowed ulnocarpal space
= Colle’s fracture
What does this X-ray show?
Oblique fracture of the distal radius
Volar displacement and angulation
Shortened radius
= Smith’s fracture
What does this X-ray show?
Comminuted intra-articular distal radius fracture and displaced fracture of the ulnar styloid
= Barton’s fracture
What does this X-ray show?
Radial head fracture - fracture line not visible
Effusion indicated by raised fat pads is only sign of fracture
What does this X-ray show?
Radial head fracture - fracture line extends into articular surface of radial head
What does this X-ray show?
Effusion - raised fat pads
Subtle buckling of the radial head cortex anteriorly
= radial head fracture
What does this X-ray show?
Ulna dislocated posteriorly from the trochlea of the humerus
Radius has dislocated from the capitulum of the humerus
What does this X-ray show?
Elbow dislocation - ulna and radius dislocated from humerus
What do these X-rays show?
Scaphoid fracture visible on only PA and PA + ulnar deviation views
What does this X-ray show?
Transverse scaphoid waist fracture
What does this X-ray show?
Triquetrum fracture - comminution of the dorsal cortex of the triquetrum
Soft tissue swelling over the dorsum of the wrist
What does this X-ray show?
Fracture through the hamate
What does this X-ray show?
Perilunate dislocation
Dorsal dislocation of the capitate
What does this X-ray show?
4th and 5th MCP joint dislocation
What does this X-ray show?
Boxer’s fracture
Fracture of 4th and 5th metacarpal
What does this X-ray show?
Intra-articular fracture of the ring finger middle phalanx
What does this X-ray show?
Comminuted fracture of the little finger distal phalanx due to a crush injury
Transverse fracture of the ring finger middle phalanx
What does this X-ray show?
Boxer’s fracture
What does this X-ray show?
Bennett’s fracture - intra-articular fracture of the 1st metacarpal base, subluxation
What does this X-ray show?
Rolando fracture - Y shaped fracture of base of 1st metacarpal
What is the ‘position of safety’ for hand immobilisation?
Wrist at 30 degrees of flexion
MCP joint at 80-90 degrees of flexion
PIP and DIP joints fully extended at 0 degrees
What does this X-ray show?
Shenton’s line disrupted
Increased density of femoral neck due to overlapping impacted bone
Lesser trochanter more prominent than usually due to external rotation of the femur
= subcapital intracapsular fracture
What does this X-ray show?
Complete fracture of the full diameter of the femoral neck
Total displacement of the 2 fracture components
Loss of Shenton’s line
What does this X-ray show?
Intertrochanteric femur fracture
Comminution with separation of the lesser trochanter
What does this X-ray show?
Subtrochanteric femur fracture
What does this X-ray show?
Cannulated hip screws
What does this X-ray show?
Dynamic hip screw
What does this X-ray show?
Total hip arthroplasty
What does this X-ray show?
Hip hemiarthroplasty
What does this X-ray show?
Intramedullary nail
What investigation is done to assess bone mineral density? How is this done and how is it interpreted?
Dual-energy X-ray absorptiometry (DEXA)
Measures bone density at hip and produces Z and T score
Z score - number of SDs the patients bone density is below the mean for their age
T score - number of SDs below the mean for a healthy young adult
T score is used for WHO classification
What does this X-ray show?
Fracture through superior and inferior pubic rami - obturator ring is incomplete on the right
What does this X-ray show?
Step in cortical edge of pelvic ring - acetabular fracture, passes to obturator ring and through inferior pubic ramus
What does this X-ray show?
Pubic symphysis and right sacroiliac joint are widened - APC 3
What does this X-ray show?
ASIS avulsion fracture - small fragment of bone detached, pulled off by sartorius tendon
Normal appearance of unfused iliac crest apophysis - teenager
What does this X-ray show?
Loss of smooth arcuate lines
Sacral fracture
What does this X-ray show?
Lateral malleolus tip fractured distal to the ankle joint - Weber A
What does this X-ray show?
Fracture through distal fibula at level of ankle joint - Weber B
What does this X-ray show?
Distal fibula fracture, at level of ankle joint - Weber B
What does this X-ray show?
Distal fibula fracture, above level of ankle joint - Weber C
Transverse medial malleolus fracture
Distal tibiofibular joint also widened
What does this X-ray show?
Fractures of both the lateral malleolus (Weber C) and medial malleolus
What does this X-ray show?
Trimalleolar fracture - fracture of medial, lateral and posterior malleolus
What does this X-ray show? What should be done next?
Subtle widening of the ankle medially indicates instability at the distal tibiofibular joint
A Maisonneuve fracture should be suspected and images of the proximal fibula obtained
What does this X-ray show?
Pilon fracture - fracture of the distal tibia involving the articular surface of the tibia
What does this X-ray show?
Osteochondral fracture of the talar dome
What does this X-ray show?
Trimalleolar fracture - lateral malleolus fracture (Weber C), posterior malleolus fracture, medial malleolus fracture
The joint is unstable and widened anteriorly and at the distal tibiofibular syndesmosis
The talus is displaced posteriorly and laterally along with the medial and lateral malleolus bone fragments
What does this X-ray show? What should be done next?
Complete dislocation of the talus from the tibia and fibula
Get proximal views of the tibia/fibula - fibula fracture common if widening of tibiofibular joint distally
What does this X-ray show?
Complete dislocation of the talus from the tibia and fibula
What does this Xray show?
Hip dislocation - femoral head lies superior and lateral to the acetabulum
What does this X-ray show?
Hip dislocation - total hip replacement Ball of the femoral component is displaced from the cup of the acetabular component
What does this X-ray show?
Total dislocation of the knee
Tibia and fibula rotated
What does this X-ray show?
Lateral dislocation of the patella
What does this X-ray show?
Patellar fracture - wide separation of the upper and lower poles of the patella
What does this X-ray show?
Thoracic scoliosis (dextroscoliosis)
What does this X-ray show?
Kyphosis
What does this X-ray show?
Rheumatoid arthritis of the shoulder - large peri-articular erosions around humeral head, erosion of distal clavicle
Widening of acromioclavicular joint
What does this X-ray show?
Sclerosis of humeral head and glenoid fossa
Narrowed joint space
Osteophyte lower border of humeral head
= shoulder OA
Describe the X-ray appearance of slipped upper femoral epiphysis
Disruption of Shenton’s line
Steel sign - shadow behind superior femoral neck
Widening of physis, reciprocal decrease in height of epiphysis
Prominent lesser trochanter due to external rotation of hip joint
Klein’s line - line drawn along superior edge of the femoral neck fails to intersect the lateral part of the superior femoral epiphysis
What does this MRI show?
Decreased fat signal, increased fluid signal due to bone oedema adjacent to sacroiliac joints = active sacroiliitis (likely to be normal on X-ray)
