ortho

• Osteomyelitis microbiology

  • Staph. aureus is the most common cause except in patients with sickle-cell anaemia where Salmonella species predominate
• Osteomyelitis management

  • flucloxacillin for 6 weeks
  • clindamycin if penicillin-allergic
• Diabetes mellitus is a risk factor for Dupuytren's contracture, and is related to fasting blood glucose levels. Therefore, metformin would relatively reduce the risk of Dupuytren's contracture in patients with diabetes.
• Specific causes of Dupuytren's contracture include:

  • manual labour
  • phenytoin treatment
  • alcoholic liver disease
  • diabetes mellitus
  • trauma to the hand
• X-ray findings of osteolysis and joint dislocation, in conjunction with the clinical findings of a non-tender, swollen, erythematous and hot foot are pathognomonic of an acute Charcot joint

  
• A Charcot joint is also commonly referred to as a neuropathic joint. It describes a joint which has become badly disrupted and damaged secondary to a loss of sensation. In years gone by they were most commonly caused by neuropathy secondary to syphilis (tabes dorsalis) but are now most commonly seen in diabetics.
• Osler nodes are normally described as tender, purple/red raised lesions with a pale centre. These lesions occur as a result of immune complex deposition. These occur most often in association with endocarditis. However, other causes include SLE, gonorrhoea, typhoid and haemolytic anaemia.
• Heberdens nodes may produce swelling of the distal interphalangeal joint with deviation of the finger tip.
• Ganglions commonly occur in the hand and are usually associated with tendons. They are typically soft and fluctuant. They do not require removal unless they are atypical or causing symptoms.
• Bouchard's nodes - Hard, bony outgrowths or gelatinous cysts on the proximal interphalangeal joints. They are a sign of osteoarthritis, and are caused by formation of calcific spurs of the articular cartilage.
• Direct trauma to the knee can result in patella dislocation, which is associated with a positive patellar apprehension test.
• Falling hard onto a bent knee can injure the posterior cruciate ligament. This is associated with a positive posterior drawer test.
• Hyperextension knee injury most commonly results in anterior cruciate ligament rupture. This is associated with a positive anterior drawer test.
• Repeated jumping and landing on hard surfaces causes patella tendinopathy or 'jumper's knee'. It results in anterior knee pain over 2-4 weeks which comes on with exercise and worsens with jumping.
• Twisting knee injury can result in a meniscal tear (with potential medial collateral ligament sprain). The knee would be swollen and painful to palpate. McMurray's test would also be positive (painful click).
• Previous trauma to a limb, with paraesthesia (an early sign), disproportionate pain on assessment of tone (passive rather than active movements) and normal x-ray findings should raise suspicion of compartment syndrome. The syndrome can also arise in people who intensely exercise, or those with bleeding disorders like haemophilia. Management is with early referral to orthopaedic surgeons, who typically perform fasciotomy to open the compartment and relieve the pressure.