止血带对全膝关节置换术中股骨远端旋转定位时髌骨轨迹的影响

Influence of tourniquet application on patellar tracking in total knee arthroplasty

目的探讨止血带对全膝关节置换术中以外科髁上轴线为股骨远端旋转定位线的髌骨轨迹的影响。方法2002年12月至2008年8月，首选以外科髁上轴线为股骨远端旋转定位标志的初次全膝关节置换349例（526膝），男124例（155膝），女225例（371膝）；年龄33-84岁，平均68岁。膝内翻387膝，膝外翻94膝。均使用同一种保留后十字韧带的活动平台假体，由同一位手术医生操作。采用前内侧髌旁人路，以外科髁上轴线为股骨远端旋转定位线，以no thumb test检测髌骨轨迹。对髌骨轨迹不良者，缝合髌骨内上缘支持带并松开止血带。对再次检查髌骨轨迹不良者行外侧支持带松解术。术后3个月患者能够极度屈曲膝关节时摄X线片检查髌骨轨迹。结果术中no thumb test阳性138膝，其中半脱位12膝（膝外翻），髌骨倾斜126膝（膝外翻74膝）。缝合髌骨内上缘支持带并松开止血带后，no thumb test阳性40膝，其中半脱位8膝（膝外翻），髌骨倾斜32膝（膝外翻29膝）。髌骨外侧支持带松解率7．6％（40／526），膝外翻松解率39．4％（37／94）。结论在全膝关节置换术中，高压止血带对髌骨轨迹有干扰作用。术中缝合髌骨内上缘支持带并松开止血带，可降低外侧支持带松解率。

Objective To explore the influence of tourniquet application on patellar tracking with using the surgical transepicondylar axis as distal femur alignment in total knee arthroplasty （TKA）. Methods From December 2002 to August 2008, 349 cases （526 knees） of primary TKA were performed. There were 124 males and 225 females with an average age of 68 years from 33 to 84 years. A total of 387 knees had varus deformity and 94 had valgus deformity. All of prosthesis were rotating platform with posterior eruciate ligament retaining provided by Gemini MK Ⅱ. All patients underwent anterior medial parapatellar approach. The surgical transepicondylar axis had been principally used as the distal femur alignment. Patellar tracking was checked with no thumb test. For mahracking ones, we prefered to use a single retinacular closing stitch at the superior medial arthrotomy and deflate tourniquets. Patellar tracking was checked again. Finally, lateral retinacular releases （LRR） had been performed to obtain optimizing patellar tracking. Results Intraoperatively, no thumb test were positive in 138 knees, including patellar subluxation （valgus deformity） in 12 knees and patellar inclining （74 of valgus deformity and 52 of varus deformity） in 126 knees. After using a single retinacular closing stitch at the superior medial arthrotomy and deflating tourniquets, no thumb test were positive in 40 knees, including patellar subluxation （valgus deformity） in 8 knees and patellar inclining （29 of valgus deformity） in 32 knees. The total rate of LRR was 7.6% （40/526）, the rate of LRR in valgus deformity was 39.4% （37/94） and that in varus deformity and no deformity was 0.7% （3/432）. Conclusion There was significant influence of tourniquet application on patellar tracking during the TKA. We were not falsely correcting patellar tracking problems with using a single retinacular closing stitch at the superior medial arthrotomy and deflating tourniquets intraoperatively and reducing the rate of LRR.