Bowen Richard E, Dorey Frederick J, Moseley Colin F
Shriners Hospital for Children, 3160 Geneva Street, Los Angeles, California 90020-1199, U.S.A.
J Pediatr Orthop. 2002 Jan-Feb;22(1):105-11.
Many young children present to pediatric orthopaedic surgeons with genu varum and mild beaking of the medial metaphysis on x-ray. Predicting whether these deformities will progress is challenging. In addition, there is no consensus as to whether these children should all be classified as having Blount disease. To avoid this latter problem, the authors included in this study all children presenting with bowed legs, regardless of diagnosis. With the aim of improving the ability to predict progression, the authors tested the hypothesis that patients with progression have more tibial than femoral varus. The authors reviewed 173 varus limbs of 98 patients younger than 4 years old. The authors determined the angular deformity in both femur and tibia by measuring the angles between their mechanical axes and the transverse axis of the knee, and determined the contribution of tibial deformity as a percentage of the total (%DT). The metaphyseal-diaphyseal angles of the tibia (MDA) were also measured to compare the value of that test with the %DT. There were 22 limbs with progressive and 141 limbs with resolving varus. Both the MDA and %DT were significantly different between groups. Tibial varus was found to exceed femoral varus in all patients with progression and also in several patients whose deformity resolved spontaneously. Although more specific and more sensitive than the MDA, the %DT is a good, but not perfect, predictor of progression. However, all patients in this series with both a %DT >50% and an MDA of 16 degrees or greater went on to progress. Using both of these tests together may therefore provide the surgeon with a reliable indicator of the children who would benefit from surgical correction.
许多幼儿因膝内翻和X线显示内侧干骺端轻度喙状突而就诊于小儿骨科医生。预测这些畸形是否会进展具有挑战性。此外，对于这些儿童是否都应归类为患有布朗特病尚无共识。为避免后一个问题，本研究纳入了所有出现弓形腿的儿童，无论其诊断如何。为了提高预测进展的能力，作者检验了以下假设：进展型患者的胫骨内翻比股骨内翻更多。作者回顾了98例4岁以下患者的173条内翻肢体。作者通过测量股骨和胫骨的机械轴与膝关节横轴之间的角度来确定股骨和胫骨的角畸形，并确定胫骨畸形占总畸形的百分比（%DT）。还测量了胫骨的干骺端-骨干角（MDA），以将该测试的值与%DT进行比较。有22条肢体的畸形在进展，141条肢体的内翻在缓解。两组之间的MDA和%DT均有显著差异。发现在所有进展型患者以及一些畸形自发缓解的患者中，胫骨内翻均超过股骨内翻。虽然%DT比MDA更具特异性和敏感性，但它是一个良好但并非完美的进展预测指标。然而，本系列中所有%DT>50%且MDA为16度或更大的患者均出现了进展。因此，同时使用这两种测试可能会为外科医生提供一个可靠的指标，以判断哪些儿童将从手术矫正中获益。
