Haider Zakir, Shah Nikki, Acquaah Frank, Eastwood Deborah
Great Ormond Street Hospital for Children, London, UK.
J Pediatr Orthop. 2025 Jul 15. doi: 10.1097/BPO.0000000000003048.
Genu valgum is common in mucopolysaccharidoses (MPS) patients. Improved life expectancy has led to a focus on quality of life, including the management of genu valgum to preserve mobility and reduce pain. This study assesses outcomes of guided growth for coronal plane knee deformities, including correction rates, complications, and rebound deformity.
A retrospective review of patient notes was undertaken. Presugery and postsurgery standardized long leg alignment films radiographs were assessed for mechanical axis deviation (MAD), genu valgum angle, mechanical lateral distal femoral angle (mLFDA) and mechanical medial proximal tibial angle (MPTA). All patients underwent tension band plating. Statistical analysis was undertaken using Prism software (GraphPad Software Inc., San Diego, CA).
Since 2010, of 103 patients referred, 69 knees in 35 patients required surgery for genu valgum deformity. Mean radiographic follow-up was 5.5 years (24 to 110 mo). Fifty limbs (82%) corrected to a normal zone 0/1 MAD from a mean preoperative genu valgum of 19.5 degrees (range: 11.1 to 34.1 degrees). Plate removal occurred at a mean of 34 months with a mean 2.1 degrees valgus achieved (P<0.0001). Forty-four of corrected knees exhibited rebound genu valgum of 15.2 degrees (range: 12.1 to 25.4 degrees) at a mean of 17.2 months (range: 6 to 33 mo) following plate removal. In 8 knees, correction was ongoing. Early age at initial surgery was a significant predictor of recurrence (P<0.002). During treatment, 11 knees (18%) failed to correct fully. Type 4 MPS (P<0.016) and a higher preoperative genu valgum (P<0.005) were statistically significant risk factors for failure. There were no infections. In 3 limbs, screw loosening was observed.
Our study presents the largest cohort of MPS patients undergoing guided growth for genu valgum with high rates of success and low complications. Surgery should be undertaken before 20 degrees of genu valgum is evident, especially in type 4 MPS. Recurrence is common and surgery may need to be repeated. Overcorrection of the mechanical axis into varus with close follow-up may limit the number of episodes of guided growth.
Level IV.
膝外翻在黏多糖贮积症（MPS）患者中很常见。预期寿命的延长使得人们开始关注生活质量，包括对膝外翻的管理，以保持活动能力并减轻疼痛。本研究评估了引导性生长治疗冠状面膝关节畸形的效果，包括矫正率、并发症和复发畸形情况。
对患者病历进行回顾性研究。术前和术后标准化长腿对线X线片用于评估机械轴偏差（MAD）、膝外翻角度、机械性股骨远端外侧角（mLFDA）和机械性胫骨近端内侧角（MPTA）。所有患者均接受张力带钢板固定。使用Prism软件（GraphPad Software Inc.，加利福尼亚州圣地亚哥）进行统计分析。
自2010年以来，在转诊的103例患者中，35例患者的69个膝关节因膝外翻畸形需要手术治疗。影像学平均随访时间为5.5年（24至110个月）。50条肢体（82%）从术前平均膝外翻19.5度（范围：11.1至34.1度）矫正至正常区域0/1 MAD。钢板平均在34个月取出，平均获得2.1度外翻（P<0.0001）。44个矫正后的膝关节在钢板取出后平均17.2个月（范围：6至33个月）出现15.2度（范围：12.1至25.4度）的膝外翻复发。8个膝关节的矫正仍在进行中。初次手术时年龄较小是复发的重要预测因素（P<0.002）。治疗期间，1个膝关节（18%）未能完全矫正。4型MPS（P<0.016）和术前较高的膝外翻程度（P<0.005）是矫正失败的统计学显著危险因素。无感染发生。3条肢体观察到螺钉松动。
我们的研究展示了接受引导性生长治疗膝外翻的最大队列MPS患者，成功率高且并发症低。应在膝外翻明显度数达到20度之前进行手术，尤其是在4型MPS患者中。复发很常见，可能需要重复手术。将机械轴过度矫正为内翻并密切随访可能会减少引导性生长的次数。
IV级。
