Orthopaedics - General Principles Flashcards
What is compartment syndrome?
A critical increase in pressure within a confined compartment
Within what time period, should compartment syndrome be treated?
Within 6 hours - surgical emergency
Describe the pathophysiology of compartment syndrome
- Critical increase in pressure within compartment due to swelling
- Venous collapse
- Venous congestion
- Further increase in pressure
- Arterial blood flow compromised
- Reduction in perfusion pressure to tissue
- Ischaemia
- Necrosis
What are the complications of compartment syndrome? (5)
- Ischaemia
- Necrosis
- Permanent disability of region
- Limb loss
- Death
What is an example of a permanent disability that can result from compartment syndrome? Describe it.
Volkmann ischaemic contracture
Permanent flexion contracture of the forearm muscles resulting in claw-like deformity of hands, wrist and fingers
What causes Volkmann ischaemic contracture as a result of compartment syndrome?
Ischaemia results in infarcted muscle that can’t regenerate and is replaced by inelastic fibrous tissue
State 4 causes of compartment syndrome
Traumatic injury -e.g. fractures
Post-surgery - e.g. iatrogenic vascular injury
DVT
Tight casts/splints
What is the most common site for compartment syndrome?
Name some other sites
Anterior tibial compartment
Lower limb - fibular, posterior deep, posterior superficial
Forearm - ventral, dorsal
What is a common sign associated with anterior tibial compartment syndrome?
Anaesthesia in the first web space due to compression of the deep fibular nerve
What are the clinical signs associated with compartment syndrome? (6) Which ones are early signs?
Pain (early) Pallor Paraesthesia (early) Perishingly cold Paralysis Pulseless
How is compartment syndrome diagnosed?
Usually by clinical signs
If in doubt, pressure in compartment can be measured using catheter or MRI
What is the supportive management for compartment syndrome? (5)
Keep limb at neutral level Opioid analgesia High flow oxygen Fluids Remove constricting dressings
What is the definitive surgical management of compartment syndrome?
Emergency open fasciotomy
How is an emergency open fasciotomy performed?
Cut fascia in compartment to relieve pressure
Wait 2 days - if healed; suture wound, if necrotic; debridement
Why do U+Es and renal function need to be monitored closely in compartment syndrome?
Risk of rhabdomyolysis
What is rhabdomyolysis?
Rapid destruction of skeletal muscle resulting in leakage of myoglobin and other enzymes which affects kidney function
What is septic arthritis?
Infection of a joint
What is the typical presentation seen in septic arthritis?
Acute onset, single, painful, swollen joint (this presentation is septic arthritis until proven otherwise)
What are the typical causative organisms in septic arthritis? (3)
Staph aureus (most common in adults) Streptococci Neisseria gonorrhoea (young, sexually active)
What are routes of infection in septic arthritis? (3)
Bacteraemia
Direct inoculation
Spread from adjacent osteomyelitis
Name two complications of septic arthritis?
Osteoarthritis
Osteomyelitis
What is osteomyelitis?
Infection of bone
What are some alternative differential diagnoses to septic arthritis (swollen, painful joint)? (3)
Gout
Pseudogout
Rheumatoid arthritis
Psoriatic arthritis
What are some risk factors for septic arthritis? (5)
Age > 80 yrs Diabetes Immunosuppression Pre-existing joint disease - e.g. RA/OA Prosthetic joints
What signs on examination are seen in septic arthritis? (4)
Redness
Warmth
Joint effusion
Pain on passive/active movement (unable to weight-bear)
What investigations can be performed in suspected septic arthritis? (3)
Routine bloods
Joint aspiration with fluid analysis
Plain radiograph
What bloods should be done in suspected septic arthritis?
FBC ESR, CRP Urate Autoantibodies e.g. RF, ANA, anti-CCP Cultures
What does analysis of joint fluid in suspected septic arthritis involve? (4)
Gram stain
Culture
Leukocyte count
Polarising microscopy
What is seen on x-ray in septic arthritis?
Normal in early stages
May show capsule/soft tissue swelling, joint space widening
What is the management for septic arthritis? (3)
A-E assessment - including sepsis 6 if necessary
Empirical IV antibiotics
Surgical wash out - irrigation and drainage
What is antibiotic prescription in septic arthritis based on? How long are they typically prescribed for?
Joint fluid culture
4-6 weeks
What are the most common metastases to bone? (6)
Breast Prostate Thyroid Renal Lung Myeloma
Give two examples of benign tumours of bone
Osteoma
Osteoblastoma
Give two examples of benign tumours of cartilage
Chondroma
Chondroblastoma
Give an example of a benign fibrous tumour
Fibroma