计算机导航辅助人工全膝关节置换与常规手术的早期疗效比较

Comparison of initial outcomes between navigated and conventional total knee arthroplasty

目的对比分析计算机导航辅助人工全膝关节置换与常规手术的早期疗效。方法应用三维骨建模Ceravision系统辅助人工全膝关节（Ceraver France）置换21例（男5例，女16例），对比术前、术中和术后的相关资料，分析下肢力线重建和韧带平衡的结果；检查术后3个月的膝关节活动度（ROM）与额面松弛度。对照组采用常规手术进行人工全膝关节置换20例。结果Ceravision系统对下肢力线的测量和在膝内、外翻应力下的测量均较X线片更精确。所有患者均获得人工全膝关节胫、股骨假体的满意对位和韧带平衡。术后3个月的关节活动度（ROM）平均屈曲115°；无异常的膝关节松弛度；无髌骨失稳和脱位等并发症。常规手术组的绝大部分也能获得假体的满意对位植入，术后3个月的关节活动度（ROM）平均屈曲109．4°，统计学分析显示两组的ROM比较，差异无统计学意义（P=0．06），额面松弛度比较，差异有统计学意义（P=0．03）。结论应用以三维骨建模为基础的计算机辅助手术系统，优化了人工全膝关节置换，精确地截骨和三维对位，可以更好地反映假体旋转对位情况，获得良好的膝关节屈伸位下关节间隙不衡，保证良好的膝关节韧带张力与平衡稳定，避免髌-股关节并发症，取得比常规手术更合理的额面松弛度，术后的韧带平衡稳定更好，早期疗效满意。

Objective To compare the initial outcomes between the computer-navigated and conventional total knee arthroplasty, a prospective study was conducted. Methods A cohort of 21 primary total knee prostheses （Ceraver France） implanted in 21 patients using a Bone Morphing based image-free Ceravision navigation system was investigated. By comparison of the pre-operative, intra-operative and post-operative image data we analyzed the outcomes of the lower limb alignment and ligament balancing and evaluated three months post operation. 3 months post-operative check-up for the range of motion and frontal laxity of operated knees was evaluated. As control group, a serious of 20 patients underwent TKA using conventional approaches is compared. Results All femoral, tibial and patella components were implanted in satisfactory position in all patients. The Bone Morphing system showed the accuracy of components alignment and ligaments balance. Low limb alignments deviate within 3° varus and 3° valgus in frontal view. Clinical check-up （3rd month post-op） for the initial result evaluation, the average mobility （ROM） was 115°in navigated group. There were no abnormal laxity, instability and patella complications. In the conventional approach group, lower limb alignment of most cases were within 3° varus and 3° valgus in frontal view, ROM was 109.4°. There was not significant difference between two groups with regard to ROM （P=0.06）, but there was a significant difference between two groups with regard to the frontal laxity （P=0.03）. Conclusion The current prospective study showed that Bone Morphing system allowed for improvement of lower axis and rotational alignment as well as ligament balance for TKA. Improved and more accurate alignment, more idea frontal laxity and ligament balance impacted on initial clinical outcome.