目的 髋外翻(coxa valga)是发育性髋关节发育不良(Developmental dysplasia of the hip,DDH)患儿术后并发症之一,术中大转子骨骺受损被推测是可能因素,但尚无实验证实,本研究拟证实股骨大转子骨骺损伤与髋外翻的关系。方法 在建立大鼠DDH模型后,通过切开复位左侧髋关节同时损伤大转子骨骺的方法,探讨DDH术中骨骺损伤因素对预后颈干角、前倾角的影响。将43只新生SD大鼠下肢伸直襁褓位固定10 d,待出生1个月时行骨盆正位X线片,确诊其中41个左侧髋关节发生脱位(41/43)。将41只DDH大鼠随机分为骨骺损伤组(21只)和对照组(20只)。对照组于大鼠出生1个月时切开复位左侧髋关节,骨骺损伤组在切开复位左髋的同时用1 mm克氏针钻孔损伤左股骨大转子骨骺。术后1个月处死并取得左股骨标本,使用超微立体扫描仪(Epson)测取颈干角及前倾角。结果 骨骺损伤组颈干角为130.56°±3.44°,前倾角为28.57°±9.25°; 对照组颈干角为126.57°±6.04°,前倾角为28.83°±7.85°。骨骺损伤组颈干角显著大于对照组(P=0.015),前倾角比较差异无统计学意义(P=0.925)。结论 术中大转子骨骺受损的DDH大鼠颈干角更大,提示该损伤可能是发生DDH术后髋外翻的因素之一。手术中减少对大转子骨骺的干扰和损伤,或可改善术后颈干角的变化,减少髋外翻的发生。
Objective Sometimes coxa valga occur as a surgical complication for developmental dysplasia of the hip(DDH).Its cause is assumed to be intraoperative damage to trochanteric growth plate at the time of operation,but no experiment has confirmed it.The aim of this study was to corroborate the relationship between transphyseal damage and coxa valga. Methods By operating open reduction and transphyseal drilling on DDH in 43 neonatal Sprague Dawley(SD)rats and measuring neck-shaft angle and femoral anteversion,this study explored the effect of transphyseal damage on neck-shaft angle and femoral anteversion after open reduction.The legs and hips were fixed by adhesive tape in an extension and adduction position for 10 days.41 left dysplastic hips(41/43),verified on anteroposterior pelvic radiographs,were randomized,21 left hips underwent transphyseal drilling and open reduction at the age of 1 month while 20 in control group underwent open reduction.All rats were sacrificed after 1 month raising in the same condition.Forty-one left femoral speciments were scanned and input into computers for measuring to calculate neck-shaft angle and femoral anteversion. Results Mean neck-shaft angle in transphyseal trauma group was larger than in control group(130.56±3.44 vs 126.57±6.04,P=0.015).No differences existed between groups in femoral anteversion(P=0.925). Conclusion Intraoperative damage to trochanteric growth plate during operation for DDH is associated with larger neck-shaft angle.Improved understanding of these relationships may help to reduce the incidence of coxa valga and improve the prognosis of DDH in children.