Background and aim:  Post-operative pain is an important consequence of lower limb surgeries that can effect early ambulation, range of motion and duration of stay in hospital. The aim of this study was to compare and assess efficacy of adductor canal block and femoral nerve block for post-operative analgesia in lower limb surgeries performed under spinal anaesthesia.

Material and methods: Sixty patient aged 18-70 years scheduled for lower limb surgeries under spinal anesthesia were included in this prospective  study. The patients were randomly divided to two equal groups of 30 each. At the end of surgery single shot ultrasound guided adductor-canal-blockade was given with 30 ml of 0.5% ropivacaine (group A) or single shot ultrasound guided femoral nerve block was given with 30 ml of 0.5% ropivacaine  (group F).Pain was assessed on 10 point Visual analogue score at rest during 24 hours postoperatively. Postoperative analgesia consumption was also studied. Motor function was assessed with straight leg raise test.

Results: Analgesic consumption was lesser in group A as compared to group F. VAS were favorable in group A . There was prolonged loss of motor function in group F.

Conclusion: Adductor canal block and femoral nerve block provide effective post- operative analgesia in lower limb surgeries performed under spinal anaesthesia using ropivacaine 0.5%.However quadriceps muscle strength is better preserved in patients who were administered adductor canal block as compared to those who received femoral nerve block. Hence adductor canal block can be effectively and safely administered for post operative analgesia in such patients.

Keywords: Adductor canal block, Spinal anaesthesia, Ropivacaine, Femoral nerve block