膝内翻全膝关节置换术软组织平衡方法探讨

目的分析骨性关节炎膝内翻角度的组成,探讨全膝关节置换术(totalkneearthroplasty,TKA)中软组织平衡方法。方法分析1999年1月～2003年12月因骨性关节炎行TKA的100例145侧膝内翻患者,其中男18例25个膝关节,女82例120个膝关节。平均年龄62.4岁(45～80岁)。膝关节HSS(hospitalofspecialsurgery)评分38.0±3.2分。根据下肢力线情况准确截骨,恢复膝关节静态骨性对线,然后根据内翻角度组成情况决定软组织松解部位及范围。软组织松解分3步进行,即截骨前暴露时松解、截骨时松解和截骨后安装假体前彻底松解。松解要点包括:韧带及关节囊松解、骨赘清除及髌骨外侧支持带松解。结果术前膝内翻总角度为9.2±3.1°,软组织失衡性内翻占53.2%,胫骨结构性内翻占46.8%,二者差异无统计学意义(P>0.05)。胫骨结构性内翻中胫骨骨性内翻占22.8%,胫骨平台关节面磨损及破坏占24.0%。术后结果表明,平均胫骨平台截骨角度为4.3°,占膝内翻矫正度数的27.9%;软组织平衡术矫正的度数为10.7°,占膝内翻矫正度数的72.1%。术后HSS评分为87.0±4.5分,与术前比较差异有统计学意义(P<0.05)。结论骨性关节炎膝内翻角度由两方面组成:即胫骨结构性内翻和膝关节侧副韧带及软组织失衡导致的内翻。其中后者占膝内翻角度的主要部分,通过松解内侧软组织进行矫正,松解的关键部位为内侧侧副韧带胫骨侧止点及后关节囊。松解时应循序渐进,随时测试,且勿松解过度。

TECHNIQUES OF SOFT TISSUE BALANCE IN TOTAL KNEE ARTHROPLASTY OF VARUS KNEE

OBJECTIVE: To analyze formation of the varus angle of the knee due to osteoarthritis and to explore techniques of the soft tissue balance in the total knee arthroplasty(TKA). METHODS: One hundred patients with 145 varus knees (18 males, 25 varus knees; 82 females, 120 varus knees) underwent TKA from January 1999 to December 2003. Their ages averaged 62.4 years (range, 45-80 years), and their HSS(hospital of special surgery)scores were 38.0 +/- 3.2 points. Before operation,all the patients were measured in the alignment of the lower extremity, accurate bone-cutting was performed, and their static alignment was achieved. Then, the soft tissue release was made. The release performance consisted of 3 steps: release before the bone-cutting, release during the bone-cutting, and release after the bone-cutting. Release of the medial ligament and capsule, elimination of the osteophytes, and release of the lateral patellar retinaculum were more important. RESULTS: The varus angles in these patients were 9.2 +/- 3.1 degrees before operation. Among them, the varus angles caused by the soft tissue imbalance accounted for 53.2%, and caused by the bone structure accounted for 46.8%; and the latter caused by the tibia varus, 22.8%, and by the tibia plateau destruction, 24.0%. There was no significant difference between the varus angles caused by the soft tissue imbalance and the varus angles caused by the bone structure deformity (P > 0.05). According to the postoperative imaging studies, the correction degree for the varus angles by the bone-cutting was 4.3 degrees, which represented 27.9% of the total corrected angles, and the correction degree for the varus angles corrected by the soft tissue balance was 10.7 degrees, which represented 72.1% of the total corrected angles. The HSS scores were 87.0 +/- 4.5 points after operation, and the difference between preoperation and postoperation was significant. CONCLUSION: The varus knee due to osteoarthritis results from the varus angle in the bone structure and the angles caused by the imbalance of the collateral ligaments and the soft tissues around the knee. The latter causative factor is more important in the formation of the varus knee and should only be corrected through the soft tissue release. The more important part to be released is the attachments of the medial ligament and the posterior capsule. The release performance should be followed by the principles, i.e., step by step, tests at all the time, and avoidance of the excessive release.