Background and objectives: Total knee replacement (TKR) produces severe postoperative pain. Peripheral nerve blocks can be used as analgesic adjuncts for TKR, but the efficacy of a sciatic nerve block as an adjunct to a femoral nerve block is controversial. The aim of this study was to compare femoral with femoral and sciatic nerve blocks in postoperative pain management of patients undergoing total knee arthroplasty (TKA).

Methods: 42 patients were involved in the study. 20 patients received only a femoral nerve block, consisting of 20ml of 0.5% Chirocaine and 22 patients received femoral and sciatic nerve blocks, consisting of 20ml of 0.375% Chirocaine for the femoral nerve and 10ml of 0.5% Chirocaine for the sciatic nerve. The primary outcome measures used were visual analogue scale (VAS) scores for pain at 24 hours, 48 hours and 72 hours after the surgery, opiates consumption post-operatively and PCA use. The secondary outcomes were post-operative nausea and vomiting, sensory deficit, quadriceps contraction, straight leg raise, knee flexion, independent mobility and discharge from the hospital.

Results: The results showed no difference in opiate consumption, PCA use, independent mobility and time of discharge from the hospital between the two groups.

Conclusion: The study shows that the addition of a sciatic nerve block to the femoral nerve block does not provide additional benefits.