Abstract:

BACKGROUND: Continuous femoral nerve block is better than a simple analgesic treatment (morphine) during total knee replacement. Single-injection femoral nerve block does not require special equipment and expert management, and it is easy to operate and spends low cost.
OBJECTIVE: To investigate the efficacy of single-injection femoral nerve block and neural rehabilitation to relieve pain and improve rehabilitation after total knee replacement.
METHODS: A total of 40 patients were prospectively and randomly assigned to receive 40 mL of either 2.5 g/L bupivacaine (group B) or saline (group S) after total knee replacement. Blinded observers evaluated the patients for postoperative pain, morphine consumption, ambulating distances, and maximal knee flexion; pain was scored on the visual analog scale (VAS).
RESULTS AND CONCLUSION: Compared with group S patients, group B patients had significantly lower VAS pain scores in the postoperative anesthesia care unit (P < 0.05-0.01); group B patients also showed significantly lower total morphine use (P < 0.05) and a lower incidence of morphine-related side effects. Significantly more group B than group S patients could ambulate on the day after surgery (P < 0.05) and mean ambulatory distance was significantly better for group B than group S patients at discharge (P < 0.01). Knee flexion was significantly better for group B than group S patients on the second day after surgery (P < 0.01), but there was no significant difference between the two groups at discharge. Mean length of hospitalization was significantly shorter for group B than group S patients (P < 0.05). The single-injection femoral nerve block combined with neural rehabilitation can obviously relieve pain, facilitate early ambulation, and reduce the length of hospitalization in patients undergoing total knee replacement.