Orthopaedics Flashcards
Pathological fracture
fracture due to cancer.
There will be tumours evident within the bone which weaken it and cause the fracture, tumours can be primary or more commonly due to mets
Fragility fracture
fracture due to osteoporosis.
DEXA scan will show diffuse demineralisation
Burst fracture (definition, mechanism, consequence)
Type of compression fracture.
Caused by high-energy axial loading spinal trauma.
Results in disruption of the posterior vertebral body cortex with retropulsion into the spinal canal
TSF (Taylor Spatial Frame) - what is it, how does it work, what is it used for?
orthopaedic device (circular frame with various rods into the bone) used to externally fix severe fractures where the bones need realignment.
It is used when the wound is not appropriate for internal fixation.
It is continually adjusted to realign the bones and then eventually removed and the bone is internally fixed.
A very specialised procedure and an alternative to amputation
Most common cause of death following NOF surgery
pneumonia, heart failure
Back slab
A half cast - put on when there is risk of swelling
Peg fracture
Odontoid process fracture (aka peg or dens fracture) - fracture through the odontoid process of C2.
Is an intra trochanteric fracture intra or extra capsular? How do you repair it?
Extra capsular therefore can do a dynamic hip screw (DHS) because there is no compromise to head of femur blood supply
What is the Gardeners classification of NOF # ?
1 - incomplete fracture of NOF.
2 - complete fracture of NOF, no displacement. Clinical determination for DHS or THR
3 - complete fracture of NOF WITH PARTIAL displacement. Risk of necrosis. Total Hip Replacement
4 - complete fracture of NOF WITH COMPLETE displacement. Risk of necrosis. Total Hip Replacement
What are the 4 signs of OA on radiograph? (HINT: think LOSS)
Loss of joint space
Osteophytes
Subchondral scleorsis
Subchondral cysts
Fracture
A fracture is loss of continuity of the cortex of the bone +/- soft tissue injury
List the clinical signs of a fracture
Pain Swelling Crepitus Deformity \+/- adjacent structural injury
Outline the 3 stages of fracture healing
1) Reactive phase (first 48 hours) - bleeding into fracture site and inflammation forming granulation teaching
2) Reparative phase (first 2 weeks) -
- proliferation of osteoblasts and fibroblasts resulting in callus formation
- consolidation of the women bone forming lamellar bone
3) Remodelling phase (from 1 week) - remodelling of lamellar bone to cope with mechanical forces
What is the average healing time for an uncomplicated fracture?
3 weeks
What constitutes an uncomplicated fracture?
Closed, paediatric, metaphyseal, upper limb
What constitutes a complicated fracture?
Adult, lower limb, diaphyseal, open
What i the average healing time for a complicated fracture?
> 6 weeks
Stress fracture
Fracture due to bone fatigue due to repetitive strain
List the “6 As” of open fracture management
Analgesia Asses Antisepsis - swab, irrigation, cover Alignment Anti-tetanus Antibiotics
What is the most severe complication of an open fracture?
Infection with clostridium perfringes which can cause wound infection, gas gangrene, shock, renal failure and death
List the general complications of fractures
Tissue damage - haemorrhage, shock, infection, rhabdomyolysis, fat emboli
Anaesthesia - anaphylaxis, aspiration
Prolonged bed rest - pneumonia, UTI, pressure sores, muscle wasting, DVT, PE
List the specific complications of fractures (HINT: split into immediate, early and late)
Immediate - neurovascular damage, visceral damage
Early - compartment syndrome, infection, fat embolism, ARDS
Late - problems with union, AVN, growth disturbance (children), post-traumatic osteoarthritis, regional pain syndromes
Name a neurovascular complication following a humeral shaft fracture (name the nerve and the pathology)
Radial nerve –> waiters tip
Name a neurovascular complication following an elbow dislocation (name the nerve and the pathology)
Ulnar nerve –> claw hand
Name a neurovascular complication following an hip dislocation (name the nerve and the pathology)
Sciatic nerve –> foot drop
Define compartment syndrome
when the pressure in one of the muscle compartments increases to the amount that it obstructs blood flow
What pressures are (a) suggestive and (b) diagnostic of compartment syndrome?
(a) 20 mmHg
(b) 40 mmHg OR within 30 mmHg of BP
Name the three classifications of problems with fracture union
Delayed union
Non-union
Malunion
List the causative factors of problems with fracture union (HINT: think “5 Is”)
Infection Ischaemia Increased interfragmentary strain Interposition of tissue between fragments intercurrent disease (eg: malignancy)
Define malunion of a fracture
Fracture has healed in an imperfect position resulting in poor appearance and/or function
Define AVN following a fracture
Death of bone due to deficient blood supply
Which three sites are most at risk from AVN following a fracture?
Femoral head
Scaphoid
Talus
What are the signs of AVN on XR?
Sclerosis
Deformity
What are the two main causes of a #NOF?
Osteoporosis with minor trauma
Major trauma
List the risk factors of osteoporosis (HINT: think A SHATTERED)
Age Steroids Hyperthyroid / hyperparathyroid Alcohol and cigarettes Thin (BMI < 22) Testosterone low Early menopause Renal failure / liver failure Erosive bone disease (eg: RA) DM / dietary (low calcium, low vitamin D)
What will you see on examination in a #NOF?
Affected leg is shortened and externally rotated
With regards to shoulder examination - which findings are positive in adhesive capsulitis (frozen shoulder)?
Decreased external rotation (<30 degrees on both passive and active movement)
With regards to shoulder examination - which findings are positive in impingement syndrome?
Positive Hawkin’s test
With regards to shoulder examination - which findings are positive in rotator cuff injuries?
Positive Jobes test
Painful / limited external rotation
Painful / limited internal rotation
Name the muscles that make up the rotator cuff - list their function
Supraspinatus - abduction
Infraspinatus - external rotation -
Teres minor - external rotation
Subscapularis - internal rotation
Explain how you would test each rotator cuff muscle
Supraspinatus - ABduction against resistance (passive abduction tests deltoid)
Infraspinatus - external rotation against resistance whilst isolating joint at elbow
Teres minor - external rotation - as above
Subscapularis - internal rotation: hand behind back and get patient to push against hand
Which direction does the arm move with horiztonal ABduction of the shoulder?
AWAY from midline
Which direction does the arm move with horizontal ADduction of the shoulder?
TOWARDS midline
Which fractures are most likely to cause compartment syndrome?
Tibial fractures Supracondylar fractures (elbow)
What are the Ottowa Rules for ankle XR
XR the angle if there is pain in malleolar zone PLUS
(a) tenderness along posterior tib/fib
OR
(b) unable to weight bear
List some conditions associated with Dupuytren’s contracture (HINT: think BAD FIBRES)
Bent penis (peryronies disease)
AIDS
Diabetes
Family history Idiopathic Booze (alcoholic liver disease) Reidel's thyroiditis Epilepsy Smoking
Define osteoarthritis
Degenerative joint disorder in which there is progressive loss of hyaline cartilage and new bone formation at the joint surface
What is Lesague’s sign?
Back pain on straight leg raise - sign of disc prolapse
Define: spondylolistehsis
Displacement of one lumbar vertebra on another
Describe the presentation of acute cord compression
bilateral back and radicular pain
LMN signs are compression level
UMN signs below compression
Sphincter disturbance
Describe the presentation of acute cauda equina
Alternating radicular pain (legs)
Saddle anaesthesia
Loss of anal tone
Incontinence
List some causes of AVN
Fracture
Dislocation
Perthes disease and other developmental joint pathologies
Systemic disease - sickle cell, DM, pancreatitis, Gaucher’s, HIV/AIDS
Drugs - steroids
What is the difference between osteomyelitis and septic arthritis?
Osteomyelitis = infection of the bone
Septic arthritis = infection of the joint
List XR changes with osteomyelitis
Decreased bone density
Sub-periosteal reaction
Sequestrum
Which organisms are most commonly responsible for osteomyelitis?
S aureus
Streptococcus
Which organisms are most commonly responsible for septic arthritis?
S aureus
Gonococcus
Which primary tumours most commonly metastasise to bone?
Thyroid Lung Breast Kidney Prostate
How are bony mets usually treated?
Radiotherapy
Name three primary malignant bone tumours
Chondrosarcoma - tumour of the cartilage
Osteosarcoma - tumour of the bone (metaphysis)
Ewing’s sarcoma - tumour of the bone (diaphysis)
What age group do the following bone tumours present in most commonly?
(a) Chondrosarcoma
(b) Osteosarcoma
(c) Ewing’s sarcoma
(a) Adults > 40
(b) Adolescents
(c) Children
What forms the carpal tunnel?
Flexor retinaculum and carpal bones
What does the carpal tunnel contain
all the flexor tendons and the median nerve
What does the median nerve supply? (HINT: think LOAF)
Lumbricals
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
Essentially - lumbricals + thenar muscles
Which muscles supplied by the median nerve make up the thenar eminance? (HINT: think OAF)
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
List some of the causes of carpal tunnel syndrome
Primary - idiopathic
Secondary - pregnnacy, hypothyroidism, acromegaly, inflammatory joint disease (gout, RA), soft tissue swelling (eg: lipoma), diabetes, EtOH
Outline the pathology of carpal tunnel syndrome
Compression of the median nerve due to reduced space within the carpal tunnel
Explain a POSITIVE trendelenberg’s test
If there is abductor weakness, pelvis will drop to the contralateral side on leg raise
Eg: L abductor weakness causes R drop - this is felt in the examiners L hand (so if you feel drop in your left hand, the patient has a L sided weakness)
What causes an apparent leg length discrepancy?
Spinal or hip pathology
What causes a true leg length discrepancy?
Difference in length of long bones
What is Thomas’ test looking for?
Fixed flexion deformity
What is the most common cause of a fixed flexion deformity?
Osteoarthritis
List the complications of hip arthroplasty (HINT: split into immediate, early and late)
Immediate - nerve injury, fracture, cement reaction, haemorrhage
Early - DVT, infection, dislocation
Late - loosening, infection, leg length discrepancy, revision
List the complications of knee arthroplasty (HINT: split into immediate, early and late)
Immediate - fracture, cement reaction, vascular injury, haemorrhage, nerve injury
Early - DVT, deep infection
Late - loosening, peri-prosthetic fractures, decreased ROM, instability (ACL is sacrificed during surgery)
List some differentials for knee locking
Meniscal tear
Cruciate ligament injury
Loose body
Outline the presentation of an ACL tear
Associated with declaration or rotational movement
Inability to continue with activity / sport
Hearing a pop / feeling a tearing sensation
Haemarthrosis within 6 hours
Instability / sensation of giving way
List the most common cause of the following gait abnormalities:
(a) antalgic
(b) trendenlenberg
(c) parkinsonian
(d) broad based
(e) high stepping
(f) spastic
(a) antalgic = pain
(b) trendenlenberg = weak abductors
(c) parkinsonian = PD
(d) broad based = cerebellar
(e) high stepping = common peroneal nerve injury
(f) spastic = UMN, eg: stroke
List some differentials for popliteal swelling
Popliteal aneurysm Bakers cyst Enlarged bursae Skin pathology (eg: lipoma) Neruoma
What is a Baker’s cyst?
Posterior herniation of knee joint capsule
