RESUMEN
BACKGROUND: Osteoarthritis is a common cause of inactivity and reduced quality of life in the elderly. Total knee replacement (TKR) surgery, a last-stage treatment option for osteoarthritis, often results in postoperative pain that influences knee flexion and the ability to perform prescribed rehabilitation exercises. PURPOSE: This study was designed to examine the effectiveness of single femoral nerve block (FNB) on pain level and knee mobility in patients with TKR. METHODS: A quasi-experimental, two-group, longitudinal study was designed. The participants were distributed into the FNB group (n = 86) and non-FNB group (n = 86). The outcome measurements included pain scale (Numerical Rating Scale) score and knee continuous passive motion knee flexion angle. The five assessments and followed-up times were as follows: admission day (T0) and post-surgery day 1, 2, 3, and 4. RESULTS: The results of the generalized estimating equations model showed that the pain level in the FNB group was significantly lower than in the non-FNB group, (p < .001). In terms of analgesics demand from post-surgery day 1 to day 4, the FNB group exhibited a significantly lower demand than the non-FNB group (p < .01). In addition, significant differences in the continuous passive motion rehabilitation exercise angle were found between the two groups from post-surgery day 1 through day 4 (p < .05). Finally, significant differences in knee flexion angles between the two groups were observed between hospital admission and discharge (p < .001). CONCLUSIONS / IMPLICATIONS FOR PRACTICE: The findings of this study support the positive effects of the femoral nerve block intervention on patients who receive total knee replacement surgery. The results were significant in terms of pain relief and knee mobility recovery. This intervention should be made available for use in the clinical care of TKR patients.