Abstract
Wound complications are much more common following knee arthroplasty as compared to hip arthroplasty, due in part to the precarious blood supply to the knee, as well as the subcutaneous position of the joint. Many, if not most, infections are related to wound problems, and thus avoiding wound problems is a critical issue in knee replacement surgery.
Many wound problems are avoidable and can be minimised by care to detail by the surgeon. The important steps are to first identify patients at risk and optimally addressing these risk factors. Patient risk factors include: chronic corticosteroid use, diabetes, rheumatoid arthritis, malnutrition, obesity, and smoking.
Soft tissue handling is a second major issue. Minimal incision surgery should be used with great caution for knee replacements since the skin is much less forgiving than in hip replacements. A midline skin incision should be utilised when possible. When multiple incisions are present it is usually advisable to use the lateral most incision through which it is feasible to perform a knee replacement. In rare cases, a soft tissue expander may be used pre-operatively for thin, adherent skin.
Peri-operative steps that can be taken include delaying CPM in high risk wounds, and using a wound vac system in obese or other high risk wounds to minimise persistent drainage. Furthermore, anticoagulation should be used judiciously to avoid prolonged drainage. The final step in salvaging the problem wound is early recognition and aggressive management of wound healing problems. Prolonged, serous drainage is the most common clinical scenario. Drainage that is increasing beyond 5–7 days frequently requires evacuation, irrigation, debridement, and liner exchange. Early aspiration can decompress a hematoma and also rule out infection.
