General Principles ortho

Question 1

Principles of fracture management

Answer 1

(High-energy injuries resus following ATLS)

1. Reduce - restoring anatomical alignment - reduce bleeding/ traction so swelling/ neuropraxia/ pressures on BVs
   ✅analgesia ✅conscious sedation
2. Hold - immobilising - simple splints/ plaster casts (not circumferential first 2wks, if axial instability needs cross joint above & below)
   ✅May thromboprophylaxis ✅advice compartment syndrome
3. Rehabilitate - intensive physiotherapy
   ✅May occupational therapists

Question 2

How common is osteoarthritis? What is the pathophysiology?

Answer 2

Most common arthropathy
Leading cause of pain & disability in the western world
Knee OA 15% >55yrs
Radiographic incidence >80% >75yrs

Progressive loss articular cartilage & remodelling underlying bone - active response chondrocytes in cartilage & inflammatory cells in tissues -> enzymes break down collagen & proteoglycans-> subchondral bone exposed -> sclerosis -> remodelling -> osteophytes & bony cysts, loss of joint space

Question 3

Clinical features of oesteoarthritis

Answer 3

Common joints: hands, feet, hip, knees

Insidious, chronic, gradually worsen, pain & stiffness, worsened with activity & relieved rest, pain worse through day stiffness improves
-> deformity, reduced range movement

Bourchard nodes (swelling PIPJs)
Heberden nodes (DIPJs)
Fixed flexion/ Varus malalignment knees 

Crepitus
Reduction joint movement

Question 4

Differentials for oesteoarthritis

Answer 4

Inflammatory arthropathy ex (RA)
Crystal arthropathies (gout, CPPD)
Septic arthritis 
Fractures
Bursitis
Malignancy 

Hand - RA, gout, De Quervain’s tenosynovitis
Hip - trochanteric bursitis, radiculopathy, spinal stenosis, iliotibial band syndrome
Knee - referred hip, meniscal or ligament tears, chondromalacia patellae

Question 5

Investigations for oesteoarthritis

Answer 5

Primary clinical diagnosis

Routine bloods - exclude inflammatory/ infective 
Radiograph:
- loss joint space
- osteophytes
- subchondral sclerosis
- subchondral cysts

Question 6

Management of oesteoarthritis

Answer 6

Conservative:
Advice joint protection, strengthening & exercising,
WL

Heat/ ice packs
Joint supports
Physiotherapy

Medical: simple analgesics, topical NSAIDs, intra-articular steroid injections (may worsen few days)

Surgical:
Osteotomy
Arthrodesis (joint fusion)
Arthroplasty

Question 7

What are the most common open fracture sites?

Answer 7

Tibial, phalangeal, forearm, ankle, metacarpals

Question 8

How can the outcomes of open fractures be divided?

Answer 8

• skin if significant May need skin grafting/ local/ free flap
• soft tissues may muscle/ tendon/ ligament loss -> reconstructive surgery
• Neurovascular injury compressed/ arteriospasm/ intimal dissection/ transected
• infection contamination/ reduced vascularity/ systemic compromise/ insertion metalwork

Question 9

Gustilo-Anderson Classification of open fractures

Answer 9

Type 1 <1cm wound & clean

Type 2 1-10cm wound & clean

Type 3A >10cm high energy, soft tissue coverage (orthopaedics alone)

Type 3B >10cm high energy inadequate ST coverage (plastics)

Type 3C vascular injury (vascular input)

Question 10

Investigations for & management open fractures

Answer 10

G&S
Basic blood tests (clotting)
Radiograph
Complex/ communited CT

✅resus & stabilisation 
✅realignment & splinting 
✅document neurovascular status 
✅broad antibiotics 
✅ tetanus vaccine if not up to date
✅photograph wound 
✅ remove gross debris 
✅ wound dressed saline stacked gauze 

Definitive management:
Debridement <12-24hrs if not contaminated
Washed out saline
Skeletal stabilisation

Question 11

What is compartment syndrome? Where is most commonly affected?

Answer 11

Critical pressure increase within confined compartmental space

Any fascial compartment, most common: leg, thigh, forearm, foot, hand, buttock

Question 12

Pathophysiology of compartment syndrome?

Answer 12

Typically following high-energy trauma, crush injuries or fractures -> vascular injury

Other causes: iatrogenic vascular injury , tight casts/ splints, DVT, post-reperfusion swelling

Closed non-distend-able space -> Fluid deposited -> ⬆️intracompartmental P -> compresses veins -> ⬆️hydrostatic P in veins -> fluid moves out of veins -> traversing nerve red compressed -> sensory/ motor deficit (paraesthesia) -> arterial inflow compromised -> ischaemia (cold, pale, pulsesless, paralysed) - late sign

Question 13

Clinical features of compartment syndrome

Answer 13

Tend present within hrs - up to 48hrs post insult

Severe pain disproportionate injury, not readily improved, pain worse passively stretching muscle bellies, paraesthesia distal, compartment tense -> acute arterial insufficiency (5 Ps)

Question 14

Investigations & management of compartment syndrome

Answer 14

Clinical diagnosis - intra-compartmental pressure monitor, creatine kinase elevated

Management:
Urgent fasciotomies -> skin incisions left open re-look 24-48hrs

• keep limb neutral level
• High flow O2
• augment BP crystalloid fluid bolus
• remove dressings/ splints/ casts
• opioid analgesia
• monitor renal function (rhabdomyolysis/ reperfusion injury)

Question 15

What is the main cause of septic arthritis (infection of a joint)? How does it occur and what can it lead to?

Answer 15

Main causative organisms: staphylococcus aureus, streptococcus spp, gonorrhoea, salmonella (SCD pts)

Seed to join from: bacteraemia (cellulitis, UTI, chest infection), direct inoculation, adjacent osteomyelitis

• > irreversible articular cartilage damage
• > severe osteoarthritis

Question 16

A pt with RA, chronic renal failure & an IV drug user presents with a swollen knee joint causing severe pain. The knee appears red, swollen & warm causing pain on movement & they are unable to weight bear. What is the likely cause? How else May they present? What else could it be?

Answer 16

60% Pyrexia
Effusion sometimes

Prosthetic joints more subtle features

DD:
Flare OA
Haemarthrosis
Crystal arthropathies (gout/pseudo)
RA
Reactive arthritis
Lyme disease (borrelia burgdoferi)

Question 17

How do you investigate suspected septic arthritis?

Answer 17

Routine bloods (FBC, CRP, ESR, urate)
Blood cultures
Joint aspiration - fluid analysis gram stain, leukocyte, polarising microscopy, fluid culture 

Imaging: 
Plain radiograph (early normal-> swelling, fat pad shift, joint space widening)

Further imaging rare

• USS guide joint aspiration & drainage
• Ct/ MRI uncertain/ sternoclavicular/ sacroiliac
• radionuclide scans isolated joints

Question 18

Management of septic arthritis & complications

Answer 18

Early resus

Empirical antibiotic after planned cultures/ aspirates 4-6wks (IV 2)

Native joints - surgical irrigation & debridement (washout)
Prosthetic - revision surgery & washout

Complications:
OA
Osteomyelitis

Question 19

Where is osteomyelitis (infection of the bone) most common & how is it caused?

Answer 19

Adults - vertebrae
Children - long bones

Most cases acute & bacterial in origin
Some chronic & rarely fungal
Causes: haematogenous spread, direct inoculation, direct spread nearby infection
Causative organisms: staphylococcus aureus, streptococci, enterobacteur spp, haemophilus influnzae, P aeruginosa (IV drug), salmonella spp (SCD pts)

Question 20

Pathophysiology of acute & chronic osteomyelitis

Answer 20

Bacteria enter bone tissue -> adhesions bind host tissue proteins -> polysaccharide extracellular matrix -> propagate, spread seed further

Chronic: devascularisation -> necrosis -> resorption bone -> floating dead bone (sequestrum) reservoir infection (not penetrated antibiotics) -> may get involucrum (encases thick sheath periosteal new bone)

Question 21

Clinical features of osteomyelitis

Answer 21

Severe pain unless diabetic foot - constant, worse night
Low grade pyrexia 
May history trauma
Tender
Swelling
Erythema
Unable weight bear

Examine sources infection: pock marks, sinuses, cellulitic areas, penetrating wounds, stigmata concurrent infection

Question 22

Investigations for osteomyelitis

Answer 22

Routine bloods (FBC, CRP, esr)
Blood cultures (+ve 60%)

Plain film radiograph (visible 7-10 days post infection) May osteopenia, periosteal thickening, endosteal scalloping, focal cortical bone loss

• MRI definitive

Bone biopsy culture >90% sensitivity ⭐️

Question 23

Management osteomyelitis & complications

Answer 23

LT IV antibiotics >4wks if clinically well

Deteriorates - surgical management - curettage

Complications: overwhelming sepsis, septic arthritis, soft tissue infections, growth disturbances, recurrence, chronic osteomyelitis (ongoing bone pain, non specific infection symptoms, draining sinus tract, normal inflammatory markers often, -ve cultures ✅debridement, LT antibiotics, staged reconstruction/ amputation)