国人类风湿关节炎术中髌骨厚度的测量及置换技术的探讨

Measurement of patellar thickness and surgical techniques of patella resurfacing during total knee arthroplasty in Chinese patients with rheumatoid arthritis

[目的]调查国人类风湿关节炎中髌骨的厚度及解剖学特点,探讨髌骨置换术的方法和安全性。[方法]自2005年1月～2006年1月,对59例患者95个类风湿膝关节行全膝置换术,术中测量髌骨最厚处、最薄处和髌骨截骨后骨床的厚度以及安装髌骨假体后髌骨复合物厚度,术后对患者随访,观察膝前痛和髌骨骨折的发生率。[结果](1)截骨前髌骨的厚度测量为最高处(22.01±1.64)mm(18～26mm),最低处为(11.69±2.33)mm(6～16mm)。(2)截骨后髌骨的骨床厚度测量结果为(13.23±0.96)mm(11～16mm),其中11mm4膝(4.2%),12mm15膝(12.7%),13mm38膝(40%),14mm32膝(33.7%),15mm5膝(5.3%),16mm1膝(1.1%)。髌骨复合物的厚度平均为21.42mm(20～25mm),90.5%(86/95)的髌骨厚度在术后等于或稍低于原髌骨厚度。(3)术后随访轻度膝前痛3例,无髌骨骨折或髌骨松动病例。[结论](1)类风湿膝关节中髌骨的厚度小于国人正常髌骨厚度的均值。(2)类风湿膝关节髌骨置换时保留12～14mm厚度的骨床是一种安全的选择。(3)类风湿膝关节置换髌骨短期随访临床疗效肯定。

[ Objective ] To measure the patella thickness and to investigate the techniques and safety of patella resurfacing during total knee arthroplasty in Chinese patients with rheumatoid arthritis. [ Methods] From Jan. 2005 to Jan. 2006, the maximal and minimum thickness of the patella , the preserved thickness of bony patella after resurfacing and the total thickness of patella composite after patella replacement in 95 consecutive total knee arthroplasty for rheumatoid arthritis were measured. The patients were followed - up after operation, anterior knee pain and patella fracture were recorded. [ Results] 1 ） The mean maximal thickness before resurfacing was （22.01 ± 1.64） mm （range, 18 -26 mm） , the mean minimum thickness before resurfacing was （11.69 ±2. 33 ） mm （range , 6 - 16mm） . 2） The mean thickness of preserved bony patellar thickness was （13.23 ±0. 96） mm, （range, 11 -16 mm）, including 11 mm in 4 knees （4.2%） , 12 mm in 15 knees （12.7%）, 13 mm in 38 knees （40%）, 14 mm in 32 knees （33.7%）, 15 mm in 5 knees （5.3%） and 16 mm in 1 knee （ 1.1% ） . The mean thickness of the patella composite was 21.42 mm （range, 20 -25 mm）, the thickness of resurfaced patella was equal to or thinner than the preoperative patellar thickness in 86 knees （90. 5% ） . Anterior knee pain was found in 3 knees, but no patellar fracture or component loosening occurred. [ Conclusion ] 1 ） The patellar thickness in rheumatoid arthritis is thinner than the thickness in normal patella. 2） It is a safe option to retain bony patella thickness at 12 - 14 mm during patellar resurfacing in Chinese adults with rheumatoid arthritis. 3） Patellar resurfacing in patients with rheumatoid arthritis has a good result in a short term. Careful attention to good surgical technique in component alignment and patellar resurfacing is crucial to obtain good results.