Effect of joint immobilization using extension splint immediately after total knee arthroplasty on post-operative knee function and pain: a randomized clinical trial

Purpose Investigate the effect of semirigid extension bracing after total knee arthroplasty (TKA) on articular pain and function. Methods The present randomized clinical trial included 72 patients undergoing unilateral primary TKA. Patients in the case group received eight days of post-operative semirigid extension-locked knee bracing, whereas controls did not. The outcomes assessed preoperatively and on the first, ninth, 30th day, and one year post-operatively included the knee society score (KSS), functional KSS (FKSS), VAS pain score, amount of postoperative opiate painkiller usage (tablet oxycodone 5mg), and knee ROM. Results The case group had a significantly lower flexion ROM on postoperative day nine compared to the control group (95.3 degrees vs. 100.8 degrees, p=0.03), while it became significantly higher 1 month (114.1 degrees vs. 104.7 degrees, p=0.03) and one year post-operative (128.0 degrees vs. 120.5 degrees, p=0.002). Also, FKSS was significantly higher in the case group than in the controls in the one month post-operative assessment (37.0 vs. 32.6, p=0.009) but not in the one year post-operative assessment. The case group patients had a significantly lower pain than the controls on days one (5.8 vs. 7.2, p=0.02) and nine post-operative (4.1 vs. 5.2, p=0.048), but not at later assessments. The amount of one month post-operative opium (oxycodone) consumption was significantly lower in the brace group (12.4 vs. 14.1 tablets, p=0.03). The KSS were not significantly different between the groups after the surgery. Conclusion Extension-locked splinting immediately after TKA is a noninvasive, non-pharmacological, and inexpensive intervention with possible promising effects on knee ROM, short-term functional improvement, and acute post-operative pain management.