Aim and objective: The aim of this study was to compare postoperative side effects produced by spinal bupivacaine plus buprenorphine with femoral and sciatic nerve blocks plus spinal bupivacaine. Settings and Design: Randomly patients were divided in to 2 groups by using computer generated randomization, 25 patients weretaken in each group they are Group – A (spinal bupivacaine plus buprenorphine) and Group – B (Combined femoral and Sciatic Nerve Block plus spinal bupivacaine ). Patients and Methods: Postoperative side effects like nausea and vomiting, itching, drowsiness, sedation and prolonged sensory & motor block produced and hemodynamic variability was documented and compared between both groups (A and B). Statistical analysis: Done using Chi-square test. Results: The Nausea and vomiting,itching, drowsiness and sedation was high with Group A and prolonged sensory & motor block was high with Group B (p value < 0.01 highly significant). Hemodynamic variability was not significant between both groups. Conclusion: Nerve blocks (femoral & sciatic) compared to intrathecal buprenorphine are very useful, with less side effect for post operative pain relief.