成人髋臼发育不良全髋置换的髋臼重建

Acetabular Reconstruction of Total Hip Arthroplasties for Dysplatic Acetabulum in Adults

目的探讨应用全髋关节置换术治疗髋臼发育不良继发骨性关节炎时臼杯假体安放的方法及其对手术疗效的影响。方法对48例(56髋)髋臼发育不良行全髋置换时,部分应用髋臼内陷成形术向内或内下方加深髋臼并选择小型臼杯假体。通过Ranawat三角测量术前及术后股骨头中心距理想旋转中心的水平和垂直距离,应用Mark髋臼四分法判断臼杯假体的实际位置。行Harris临床评分及X线检查做为疗效判定标准。结果Ranawat三角测量,术前股骨头中心距理想旋转中心的水平距离平均为18.2 mm,术后为1.52 mm;术前垂直距离平均为10.26 mm,术后为5.68 mm。手术前后比较,差异有统计学意义(P<0.01)。Mark髋臼四分区中,臼杯假体位于内侧区者为46髋,其中内下区34髋。术前Harris评分为32.5～60.3分,术后为76.6～96.5分。无假体松动和移位,无翻修病例。结论在髋臼发育不良行全髋置换的髋臼重建中,应强调向内方或内下方加深髋臼,接近于真臼安放臼杯假体,以尽量恢复髋关节理想旋转中心;选择小型臼杯假体以获得髋臼宿主骨的良好覆盖,减少髋臼植骨的机会。

Objective To explore the methods and the effects of placement of the acetabular components in treatment of degenerative osteoarthrosis secondary to congenital dysplasia of acetabulum with total hip arthroplasties （THA）. Methods In hip replacement with small cup components for 48 patients （56 hips）, the acetabula were deepened an ostetory of acctabular medial wall （cotyloidplasty） was used. The Ranawat triangle was separately used to measure horizontal and vertical distances between the femoral head center and the optimal rotating center. The initial position of the acetabular cup was assessed by the Mark four - zone system. The results was evaluated with the Harris hip score system and radiographic parameters. Results The mean horizontal distance was 18.2 mm preoperatively and 1.52 mm postoperatively, and the mean vertical distance was 10.26 mm preoperatively and 5.68 mm postoperatively. There was statistical difference （P 〈 0.01）. With use of the four - zone classification described, 46 cups were in medial region, 34 of the 46 cups were in region of inferior and medial, accounting for 68 percent of total cups. The Harris hip score was 32.5 -- 60.3 points preoperatively and 76.6--96.5 points postoperatively. No patients had revision, loosening or migration of the acetabular component. Conclusion We suggest that the acetabulum towards medial region or inferior and medial region be deepened, and the acetabulum be reconstructed by po- sitioning the hip center as close as possible to the anatomic hip center. It is emphasized to try to recovery the optimal rotating center in the THA. A small cup can obtain adequate coverage of the socket by the ilium, and can reduce the use of bone - grafting.