正常儿及发育性髋脱位患儿保守治疗后股骨Alsberg角的演变规律研究

Early prediction of lateral growth disturbances of proximal femoral physis after conservative treatment of developmental dysplasia of the hip

目的探讨正常儿童及发育性髋关节发育不良（developmental dysplasia of the hip，DDH）患儿保守治疗后，Alsberg角随年龄的变化规律，及其是否可以早期预测Kalamchi-MacEwenⅡ型股骨头坏死。方法在标准的骨盆正位片上，测量1～10岁正常儿的股骨近端Alsberg角，每个年龄段测量100例，共1000例；同时，测量112例行保守治疗（Pavlik支具或闭合复位）DDH患儿术前的Alsberg角，并与年龄匹配的正常儿比较。对随访至骨成熟期，获得成功复位（同心复位，无股骨头坏死发生）的42例（64髋）患儿，及24例（28髋）发生Kalamchi—MacEwen Ⅱ型股骨头坏死的患儿，回顾性分析复位后Alsberg角随年龄的演变规律。结果正常儿Alsberg角随年龄呈下降趋势，1岁时左侧平均为76．5°±3．4°，右侧为76．7°±4．6°；10岁时降至左侧65．2°±4．1°，右侧64．7°±4．3°。左右侧间差异无统计学意义（P=0．087）；不同性别间差异也无统计学意义（左侧P=0．072，右侧P=0．342）。DDH患儿组，治疗前Alsberg角平均为81．5°±3．9°，年龄匹配的正常儿为74．9°±4．5°（P〈0．001）。获得成功复位的患儿，复位后Alsberg角逐年下降，最后随访时平均为68．4°±6．0°（56°～88°），接近同龄正常儿。在Ⅱ型股骨头缺血性坏死组，治疗前Alsberg角平均为80．4°±4．6°（74°～86°），最后随访时为86．2°±5．5°（70°～97°）。结论正常儿童股骨近端的Alsberg角随生长发育逐年减小，DDH患儿的Alsberg角较同龄正常儿明显增大，但获得成功复位后，Alsberg角逐渐恢复正常发育。但在发生Ⅱ型股骨头缺血性坏死患儿，治疗后Alsberg角不随年龄减小，反而增大。因此，Alsberg角可能是DDH保守治疗后发生Kalamchi-MacEwenⅡ型股骨头坏死的早期预测指标。

Objective To evaluate the development of Alsberg angle of proximal femur in normal children and patients with developmental dysplasia of the hip （DDH） undergoing successful closed reduction without severe complications and confirm whether Alsberg angle is valuable for early prediction of lateral growth disturbances of proximal femoral physis. Methods Alsberg angle was measured on anterior-posterior pelvic radiograph in 1,000 normal children aged 1-10 years and 112 preoperative DDH patients （160 hips） undergoing closed reduction. Forty-two patients （64 hips） with reduced concentricity and without severe complications and 24 patients （28 hips） with lateral growth disturbances of proximal femur were followed up until skeletal maturity. Serial measurements of Alsberg angle were reviewed and analyzed retrospectively. Results Decreasing with age in normal children,Alsberg angle was an average of 76 at age 1 and 65 at aged 10. No significant difference existed between left and right sides or genders. The average preoperative Alsberg angle was 81.5 in DDH hips. And it was significantly larger than that in normal age-matched children. At the last followup, the average Alsherg angle was 68. 4 in successfully reduced patients and 86. 2 in those with lateral growth disturbances of proximal femur. Conclusions Alsberg angle is larger in DDH hips than that in normal controls. If hip is reduced concentrically without complications, it restores the normal trend of development. Contrarily,Alsberg angle remains unchanged or increases if there is disturbed growth of lateral capital epiphysis. Therefore Alsberg angle may become an early predictor for lateral growth disturbances of proximal femur.