Motor-sparing analgesia after total knee arthroplasty (TKA) is crucial. The primary endpoint was the postoperative visual analogue scale (VAS) score after triple injection peri-sartorius (TIPS) block after TKA. Secondary endpoints were postoperative morphine consumption, 24-h postoperative ambulation distances and the degrees of active knee extension. After general anaesthesia or spinal anaesthesia administration and before surgical incision, 80 patients undergoing TKA were randomised into group TIPS (received ultrasound-guided TIPS block where 40 ml 0.25% bupivacaine and 4 mg dexamethasone were injected: 10 ml at the distal femoral triangle, 10 ml above the sartorius and 20 ml at the distal adductor canal) and group FNB (femoral nerve block; received ultrasound-guided FNB with 20 ml 0.25% bupivacaine mixed with 4 mg dexamethasone). Postoperative pain score was noted and compared. Dynamic VAS scores were lower in the TIPS group than in FNB, while the resting VAS scores were not significantly different. Mean (standard deviation [SD]) postoperative morphine consumption was 5.82 (2.47) mg in the TIPS group (95% confidence interval [CI] 5.03,6.61) versus 9.87 (2.99) mg in the FNB group (95% CI 8.91,10.83). Ambulation distances and active postoperative knee extension in the TIPS group showed greater significance than in the FNB group (TIPS: 18.0 [7.37] m, 95% CI 15.64,20.35] vs. FNB: 8.95 [5.93] m, 95% CI 7.05,10.84) and (TIPS: 52.12 [16.39], 95% CI 46.88,57.33 vs. FNB: 26.05 [11.10], 95% CI 22.501,29.59). Nausea was more evident in FNB patients. TIPS block provides superior analgesia than FNB with motor sparing of the quadriceps after TKA.