[Peroneal nerve palsy after total knee arthroplasty under continuous epidural anaesthesia].

BACKGROUND: Peroneal nerve palsy is a rare but distressing complication of total knee arthroplasty (TKA). After introducing a standardised intraoperative and postoperative epidural anaesthesia protocol under otherwise unchanged perioperative management, we noted a sudden cumulation of peroneal nerve palsies after TKA. PATIENTS AND METHODS: In this retrospective study we checked the patients' histories for well-known risk factors for nerve lesions after TKA as well as for those risk factors controversially discussed in the literature.
RESULTS: We found an additive harmful impact of epidural anaesthesia leading to unrecognised pressure on the peroneal nerve, which caused, in combination with a pressure lesion of the pneumatic tourniquet, an axonal lesion in terms of a double-crush syndrome. By lowering the pneumatic tourniquet pressure and carefully positioning the operated leg, we found a clearly reduced risk of nerve lesion while preserving the advantages of epidural anaesthesia for the patient.
CONCLUSION: To prevent a peroneal lesion after TKA while using continuous epidural anaesthesia, we strongly recommend limiting the pneumatic tourniquet pressure to 320 mmHg while ensuring pressure-free positioning of the operated leg.