Abstract：
BACKGROUND: Genu valgum is a well-known feature of multiple hereditary exostoses (MHE). Though prior reports have demonstrated successful treatment with hemiepiphysiodesis, details regarding the correction rate and comparison to an idiopathic population are lacking. This study aimed to detail our institution\'s experience with guided growth of the knee in patients with MHE and compare this to an idiopathic population.
METHODS: All pediatric patients (age 18 and younger) with MHE who underwent lower extremity hemiepiphysiodesis at a tertiary care medical center between January 2016 and December 2022 were retrospectively reviewed. Preoperative and postoperative mechanical lateral distal femoral angle (mLDFA) and medial proximal tibial angle (MPTA, the primary outcomes) were measured in addition to mechanical axis deviation (MAD) and hip-knee-ankle angle (HKA). Patients were 1:2 matched based on age, sex, and physes instrumented to a cohort with idiopathic genu valgum.
RESULTS: A total of 21 extremities in 16 patients with MHE underwent hemiepiphysiodesis of the distal femur, proximal tibia, and/or distal tibia. The mean age at surgery was 11.7±2.2 years. Mean MAD corrected from zone 1.9±0.7 to -0.3±1.5, while mLDFA corrected from 83.4±2.9 to 91.7±5.2 degrees and MPTA corrected from 95.3±3.6 to 90.5±4.0 degrees in distal femurs and proximal tibias undergoing guided growth, respectively. Three extremities (14.3%) experienced overcorrection ≥5 degrees managed with observation. There were no differences in correction rates per month for mLDFA (0.54±0.34 vs. 0.51±0.29 degrees, P =0.738) or MPTA (0.31±0.26 vs. 0.50±0.59 degrees, P =0.453) between MHE and idiopathic groups. For 11 extremities in the MHE group with open physes at hardware removal, they experienced a mean recurrence of HKA of 4.0±3.4 degrees at 19-month follow-up.
CONCLUSIONS: Hemiepiphysiodesis corrects lower extremity malalignment in patients with MHE at a similar rate compared with an idiopathic coronal plane deformity population. Rebound deformity of 4 degrees at 19 months after hardware removal in patients with remaining open growth plates should make surgeons conscious of the remaining growth potential when planning deformity correction.
METHODS: Level III.
METHODS: All pediatric patients (age 18 and younger) with MHE who underwent lower extremity hemiepiphysiodesis at a tertiary care medical center between January 2016 and December 2022 were retrospectively reviewed. Preoperative and postoperative mechanical lateral distal femoral angle (mLDFA) and medial proximal tibial angle (MPTA, the primary outcomes) were measured in addition to mechanical axis deviation (MAD) and hip-knee-ankle angle (HKA). Patients were 1:2 matched based on age, sex, and physes instrumented to a cohort with idiopathic genu valgum.
RESULTS: A total of 21 extremities in 16 patients with MHE underwent hemiepiphysiodesis of the distal femur, proximal tibia, and/or distal tibia. The mean age at surgery was 11.7±2.2 years. Mean MAD corrected from zone 1.9±0.7 to -0.3±1.5, while mLDFA corrected from 83.4±2.9 to 91.7±5.2 degrees and MPTA corrected from 95.3±3.6 to 90.5±4.0 degrees in distal femurs and proximal tibias undergoing guided growth, respectively. Three extremities (14.3%) experienced overcorrection ≥5 degrees managed with observation. There were no differences in correction rates per month for mLDFA (0.54±0.34 vs. 0.51±0.29 degrees, P =0.738) or MPTA (0.31±0.26 vs. 0.50±0.59 degrees, P =0.453) between MHE and idiopathic groups. For 11 extremities in the MHE group with open physes at hardware removal, they experienced a mean recurrence of HKA of 4.0±3.4 degrees at 19-month follow-up.
CONCLUSIONS: Hemiepiphysiodesis corrects lower extremity malalignment in patients with MHE at a similar rate compared with an idiopathic coronal plane deformity population. Rebound deformity of 4 degrees at 19 months after hardware removal in patients with remaining open growth plates should make surgeons conscious of the remaining growth potential when planning deformity correction.
METHODS: Level III.
摘要：
背景：Genuvalgum是多发性遗传性外生体（MHE）的众所周知的特征。尽管以前的报道已经证明了半表皮固定术的成功治疗，缺乏有关矫正率和与特发性人群比较的详细信息.本研究旨在详细介绍我们机构在MHE患者中引导膝关节生长的经验，并将其与特发性人群进行比较。
方法：回顾性分析2016年1月至2022年12月期间在三级医疗中心接受下肢半上皮物理固定术的MHE患儿（年龄18岁及以下）。术前和术后机械外侧股骨远端角（mLDFA）和内侧胫骨近端角（MPTA，主要结局）除了测量机械轴偏差（MAD）和髋-膝-踝角度（HKA）外。患者根据年龄为1：2匹配，性别,和physes仪器与一组特发性genuvalgum。
结果：16例MHE患者中，共有21个四肢接受了股骨远端半上皮固定术，胫骨近端,和/或胫骨远端。手术时的平均年龄为11.7±2.2岁。平均MAD从1.9±0.7区校正至-0.3±1.5，而mLDFA从83.4±2.9校正至91.7±5.2度，MPTA从95.3±3.6校正至90.5±4.0度，在股骨远端和胫骨近端进行引导生长，分别。三肢（14.3％）的过度矫正≥5度，并进行观察。mLDFA的每月矫正率没有差异（0.54±0.34与0.51±0.29度,P=0.738）或MPTA（0.31±0.26vs.0.50±0.59度,MHE和特发性组之间的P=0.453）。对于MHE组中的11个四肢，在硬件移除时具有开放的身体，在19个月的随访中，他们的HKA平均复发为4.0±3.4度。
结论：与特发性冠状平面畸形人群相比，MHE患者的上皮部固定术以相似的比率纠正下肢畸形。在计划矫正畸形时，保留开放生长板的患者在取出硬件19个月后反弹畸形4度，应使外科医生意识到剩余的生长潜力。
方法：三级。
方法：回顾性分析2016年1月至2022年12月期间在三级医疗中心接受下肢半上皮物理固定术的MHE患儿（年龄18岁及以下）。术前和术后机械外侧股骨远端角（mLDFA）和内侧胫骨近端角（MPTA，主要结局）除了测量机械轴偏差（MAD）和髋-膝-踝角度（HKA）外。患者根据年龄为1：2匹配，性别,和physes仪器与一组特发性genuvalgum。
结果：16例MHE患者中，共有21个四肢接受了股骨远端半上皮固定术，胫骨近端,和/或胫骨远端。手术时的平均年龄为11.7±2.2岁。平均MAD从1.9±0.7区校正至-0.3±1.5，而mLDFA从83.4±2.9校正至91.7±5.2度，MPTA从95.3±3.6校正至90.5±4.0度，在股骨远端和胫骨近端进行引导生长，分别。三肢（14.3％）的过度矫正≥5度，并进行观察。mLDFA的每月矫正率没有差异（0.54±0.34与0.51±0.29度,P=0.738）或MPTA（0.31±0.26vs.0.50±0.59度,MHE和特发性组之间的P=0.453）。对于MHE组中的11个四肢，在硬件移除时具有开放的身体，在19个月的随访中，他们的HKA平均复发为4.0±3.4度。
结论：与特发性冠状平面畸形人群相比，MHE患者的上皮部固定术以相似的比率纠正下肢畸形。在计划矫正畸形时，保留开放生长板的患者在取出硬件19个月后反弹畸形4度，应使外科医生意识到剩余的生长潜力。
方法：三级。
