计算机导航与非导航微创人工全髋关节置换术后髋臼倾斜角的比较

目的 探讨计算机导航与非导航（常规）的微创人工全髋关节置换术（MIS-THA）术后髋臼倾斜角的差异及其临床意义。方法连续无选择病例采用MIS-THA87例106髋,其中,47例53髋为常规MIS-THA,40例53髋采用计算机导航MIS-THA。导航组术中采用导航定位髋臼;常规组术中采用常规方法定位髋臼。两组均于术前、术后常规拍摄下肢全长X线片,双髋关节正位片,测定术后髋臼倾斜角。按髋臼倾斜角30°～50°、〈30°、〉50°和〈30°与〉50°之和分别对两组进行比较,并进行统计学处理。结果导航组手术切口长度7．2～10．5cm,平均8．9cm。常规组手术切口长度7．5～11cm,平均9．1cm。术后X线片显示,导航组术后髋臼倾斜角30°～54°,平均（40．6±5．1）°,仅1髋为54°,其余52髋均在30°～50°范围内。常规组术后髋臼倾斜角28°～70°,平均（44．2±8．7）°,其中：加髋在30°～50°范围内,〈30°为3髋,〉50°为10髋。导航组与常规组组间t’=2．56,P=0．012,有显著性差异。对两组边缘值（术后髋臼倾斜角〈30°和〉50°）,采用卡方检验。术后髋臼倾斜角〈30°组间比较差异无统计学意义,Х^2=1．37,P=0．24,;术后髋臼倾斜角〉50°组间比较差异有统计学意义,Х^2=8．22,P=0．0042;如果将两组〈30°和〉50°之和（边缘值）进行比较差异有统计学意义,X2=11．85,P=0．0006。结论 计算机导航THA是一种全新的技术,可以在MIS-THA术中将髋臼假体安放更加精确,减少变异性。

Comparison of the acetabular orientation after minimally-invasive total hip arthroplasty with and without computer-navigation: a clinical report of 106 hip in 87 patients

OBJECTIVE: To evaluate the acetabular angle after minimally-invasive total hip arthroplasty (MIS-THA) with or without computer-navigation. METHODS: 87 consecutive orthopedic patients (106 hips) underwent MIS-THA with computer-navigation (40 cases with 53 hips) or without computer-navigation (47 cases with 53 hips). The full leg length and pelvis were measured with radiography preoperatively and post-operatively. RESULTS: The average length of incision of the navigation group was 8.9 cm (7.8 - 10.5 cm), and the average length of incision of the non-navigation group was 9.1 cm (7.5 - 11 cm) The average cup inclination on the plain post-operative radiography of the navigation group was 40.58 degrees +/- 5.09 degrees (30 degrees - 54 degrees ), only the cup abduction being 54 degrees , significantly less steep than that of the control group [44.17 degrees +/- 8.71 degrees (28 degrees - 70 degrees , t' = 2.56. P = 0.012). Among the 47 control cases 40 cases showed the cup abduction of 30 degrees - 50 degrees , 3 showed the cup abduction of < 30 degrees , and 10 showed the cup abduction of > 50 degrees . The computer-navigation MIS-THA was significantly more accurate than the conventional MIS-THA. Pearson chi-square test showed that there was not significant difference in the percentage of cases with acetabular abduction < 30 degrees , between these two groups (chi(2) = 1.37, P = 0.24), and there was a significant difference in the percentage of cases with acetabular abduction > 50 degrees , between these two groups (chi(2) = 8.22, P = 0.0042). There was a significant difference in the percentage of cases with the acetabular abduction < 30 degrees and > 50 degrees calculated together between these 2 groups (chi(2) = 11.85, P = 0.0006), CONCLUSION: MIS-THA with computer-navigation allows accurate orientation of the cup implant components without direct visualization of the bony landmarks.