Shah Hitesh H, Doddabasappa Siddesh N, Joseph Benjamin
Department of Orthopaedics, Paediatric Orthopaedic Service, Kasturba Medical College, Manipal, Karnataka, India.
J Pediatr Orthop B. 2009 May;18(3):120-8. doi: 10.1097/BPB.0b013e328329dc86.
We studied case records and radiographs of 20 children with congenital posteromedial bowing of the tibia (CPMBT) retrospectively to determine the pattern of correction of the bowing, the associated growth abnormalities of the tibia and fibula, and the role of surgical intervention in CPMBT. The magnitude of diaphyseal bowing in two planes and the physeal inclination were measured. Abnormalities of ossification of the distal tibial epiphysis and inclination of the distal articular surface if present were noted and shortening of the tibia was recorded. The rate of resolution of deformity was noted from sequential radiographs and expressed as percentage reduction per month of follow-up. At initial presentation the magnitude of deformity varied; the most severe posterior diaphyseal bow was 70 degrees whereas the most severe medial diaphyseal bow was 64 degrees. Two distinct mechanisms seem to be responsible for resolution of the deformity in CPMBT; one involves physeal realignment and the other involves diaphyseal remodeling. In the first year of life, rapid resolution of angulation was noted; the rate of resolution reduced significantly thereafter. In a proportion of children with CPMBT residual deformity may persist till over 4 years of age. Physeal realignment occurred at a faster rate than diaphyseal remodeling. The degree of shortening was related to the severity of bowing and shortening as great as 40% was noted in a patient. Wedging of the distal tibial epiphysis and fibular hypoplasia with valgus inclination of the distal tibial articular surface occur in some children with CPMBT. Eccentric ossification of the distal tibial epiphysis in early childhood may be a predictor of wedging of the distal tibial epiphysis later on. We recommend all the children with CPMBT to be followed up periodically till skeletal maturity, to identify cases with residual bowing, ankle deformity, muscle weakness, and limb length inequality as active surgical intervention may be needed to correct these problems.
我们回顾性研究了20例先天性胫骨后内侧弓形弯曲（CPMBT）患儿的病例记录和X线片，以确定弓形弯曲的矫正模式、胫骨和腓骨相关的生长异常，以及手术干预在CPMBT中的作用。测量了骨干在两个平面的弓形弯曲程度和骨骺倾斜度。记录了胫骨远端骨骺骨化异常及远端关节面倾斜情况（若存在），并记录了胫骨缩短情况。从系列X线片中观察畸形的矫正率，并表示为随访每月的畸形减少百分比。初次就诊时畸形程度各异；最严重的骨干后弓为70度，而最严重的骨干内弓为64度。CPMBT中畸形矫正似乎有两种不同机制；一种涉及骨骺重新排列，另一种涉及骨干重塑。在生命的第一年，观察到角度快速矫正；此后矫正率显著降低。在一部分CPMBT患儿中，残余畸形可能持续至4岁以上。骨骺重新排列比骨干重塑发生得更快。缩短程度与弓形弯曲的严重程度相关，一名患者的缩短程度高达40%。部分CPMBT患儿出现胫骨远端骨骺楔形变和腓骨发育不全伴胫骨远端关节面外翻倾斜。幼儿期胫骨远端骨骺偏心性骨化可能是后期胫骨远端骨骺楔形变的一个预测指标。我们建议对所有CPMBT患儿进行定期随访直至骨骼成熟，以识别有残余弓形弯曲、踝关节畸形、肌肉无力和肢体长度不等的病例，因为可能需要积极的手术干预来纠正这些问题。
