外侧支持带松解对人工全膝关节置换术后膝前痛的影响

Influence of lateral retinacular release on anterior knee pain following total knee arthroplasty

目的探讨髌骨保留型人工全膝关节置换术(total knee arthroplasty,TKA)中外侧支持带松解与否对临床疗效的影响。方法采用前瞻性随机对照研究,将2012年10月—2014年10月收治并符合选择标准的132例单侧膝关节退变性关节炎患者随机分为2组(n=66),试验组TKA术中行髌骨外侧支持带松解,对照组术中不松解外侧支持带。试验组2例患者失访,对照组4例患者术中发现需松解外侧支持带,排除研究;试验组和对照组最终纳入64例和62例。两组患者性别、年龄、体质量指数、侧别、病程及术前髌骨形态、髌股关节炎分级、髌骨软骨退变等级、髌骨位置不良、髌骨轨迹不良、髌骨评分、膝关节学会评分系统(KSS)等一般资料比较,差异均无统计学意义(P>0.05),具有可比性。记录两组患者手术时间、术后引流量、住院时间、术后并发症及患者主观满意度;术后膝前痛采用疼痛视觉模拟评分(VAS)评估,采用KSS评分、髌骨评分评价膝关节功能;在X线片上测量股骨角、胫骨角、股骨屈曲角及胫骨后倾角评价假体力线;观察术后髌骨轨迹及髌骨位置,以及有无骨溶解、假体松动、髌骨骨折和髌骨坏死等并发症发生。结果术后两组患者均随访24个月。两组患者手术时间、术后引流量、住院时间、患者主观满意度比较差异均无统计学意义(P>0.05);试验组术后膝前痛发生情况优于对照组(P=0.033)。两组术后24个月KSS评分及髌骨评分均较术前显著改善(P<0.05);术后24个月时两组间比较差异无统计学意义(P>0.05)。术后发生血肿3例(试验组2例、对照组1例),轻度切口裂开4例(各2例),切口皮缘坏死1例(试验组),切口表浅感染2例(各1例),均经保守治疗痊愈;两组均未发生髌骨坏死、髌骨骨折、膝外侧痛等并发症;两组并发症发生率比较差异无统计学意义(P=0.392)。随访期间两组患者假体力线均满意,两组股骨角、胫骨角、股骨屈曲角及胫骨后倾角比较差异均无统计学意义(P>0.05)。两组骨水泥-骨界面均无透光带及骨溶解。试验组和对照组分别有3例和5例发生髌骨轨迹不良,比较差异无统计学意义(P=0.488);但试验组髌骨位置不良发生率(18.8%)明显低于对照组(35.5%)(χ~2=0.173,P=0.034)。结论髌骨保留型TKA术中行外侧支持带松解能够降低术后膝前痛发生率,并且不增加术后并发症发生风险。

Objective To investigate the effect of lateral retinacular release on the clinical outcomes after total knee arthroplasty （TKA） without resurfacing of the patella. Methods A prospective randomized controlled study was performed on 132 patients with unilateral degenerative knee arthritis undergoing TKA bewteen October 2012 and October 2014, who met the selection criteria. During TKA, lateral retinactflar release was used in 66 cases （trial group） and was not used in 66 cases （control group）. Two patients were excluded from the study due to missing the follow-up in trial group. Four patients were excluded from the study due to lateral retinacular release in control group. Finally, 64 patients and 62 patients were included in the trial group and in the control group. There was no significant difference in gender, age, body mass index, side, disease duration, preoperative patellar morphology, grading of patellofemoral arthritis, grade of patellar cartilage degeneration, patellar malposition, patellar maltracking, patellar score, and Knee Society Score （KSS） between 2 groups （P〉0.05）. The operation time, postoperative drainage volume, hospitalization time, postoperative complications, and patient satisfaction were recorded. Postoperative anterior knee pain was assessed by visual analogue scale （VAS）, and the knee joint function was evaluated by KSS score and patellar score. The femoral angle, tibial angle, femoral flexion angle, and tibial posterior slope angle were measured on the X-ray film for postoperative prosthetic alignment. The postoperative patellar tracking and patellar position, as well as the presence of osteolysis, prosthesis loosening, patellar fracture and patellar necrosis were observed. Results All patients were followed up for 24 months. There was no significant difference in operation time, postoperative drainage volume, hospitalization time, and patient satisfaction between 2 groups （P〉0.05）. The incidence of anterior knee pain in the trial group was better than that in the control group （P=0.033）. KSS score and patellar score were significantly improved in both groups at 24 months after operation when compared with preoperative scores （P〈0.05）, but no significant difference was found between 2 groups （P〉0.05）. Complications included hematoma （2 cases in the trial group, and 1 case in the control group）, mild wound dehiscence （2 cases in each group respectively）, skin-edge necrosis （1 case in the trial group）, and superficial wound infection （1 case in each group respectively）, which were cured by conservative treatment. No patellar necrosis, patella fracture, or knee lateral pain occurred in 2 groups. There was no significant difference in complication rate between groups （P=0.392）. Satisfactory implant alignment was observed in both groups during follow-up. There was no significant difference in femoral angle, tibial angle, femoral flexion angle, and tibial posterior slope angle between 2 groups （P〉0.05）. No radiolucent line at the bone-implant interface was seen around the tibial components and femoral components in both groups. The patellar maltracking was observed in 3 patients of the trial group and 5 patients of the control group, showing no significant difference （P=0.488）. However, the incidence of patellar malposition in the trial group （18.8%） was significantly lower than that in the control group （35.5%） （χ2=0.173, P=0.034）. Conclusion Lateral retinacular release during primary TKA without resurfacing of the patella can reduce postoperative knee pain without increasing complications.