Jain Mohit J, Inneh Ifeoma A, Zhu Huirong, Phillips William A
Department of Orthopedic Surgery.
Baylor College of Medicine, Houston, TX.
J Pediatr Orthop. 2020 Feb;40(2):e138-e143. doi: 10.1097/BPO.0000000000001393.
Primary treatment for Blount disease has changed in the last decade from osteotomies or staples to tension band plate (TBP)-guided hemiepiphysiodesis. However, implant-related issues have been frequently reported with Blount cases. The purpose of our study is to evaluate the surgical failure rates of TBP in Blount disease and characterize predictors for failure.
We performed an Institutional Review Board-approved retrospective chart-review of pediatric patients with Blount disease to evaluate the results of TBP from 2008 to 2017 and a systematic literature review. Blount cases defined as pathologic tibia-vara with HKA (hip-knee-ankle) axis and MDA (metaphyseal-diaphyseal angle) deviations ≥11 degrees were included in the analysis. Surgical failure was categorized as mechanical and functional failure. We studied both patient and implant-related characteristics and compared our results with a systematic review.
In 61 limbs of 40 patients with mean follow-up of 38 months, we found 41% (25/61) overall surgical failure rate and 11% (7/61) mechanical failure rate corresponding to 11% to 100% (range) and 0% to 50% (range) in 8 other studies. Statistical comparison between our surgical failure and nonfailure groups showed significant differences in deformity (P=0.001), plate material (P=0.042), and obesity (P=0.044) in univariate analysis. The odds of surgical failure increased by 1.2 times with severe deformity and 5.9 times with titanium TBP in the multivariate analysis after individual risk-factor adjustment. All 7 mechanical failures involved breakage of cannulated screws on the metaphyseal side.
Most of the studies have reported high failure rates of TBP in Blount cases. Besides patient-related risk factors like obesity and deformity, titanium TBP seems to be an independent risk factor for failure. Solid screws were protective for mechanical failure, but not for functional failure. In conclusion, efficacy of TBP still needs to be proven in Blount disease and implant design may warrant reassessment.
Level III-retrospective comparative study with a systematic review.
在过去十年中，布朗特病的主要治疗方法已从截骨术或骨钉固定转变为张力带钢板（TBP）引导下的半骨骺阻滞术。然而，布朗特病病例中与植入物相关的问题屡有报道。我们研究的目的是评估TBP治疗布朗特病的手术失败率，并确定失败的预测因素。
我们对患有布朗特病的儿科患者进行了一项经机构审查委员会批准的回顾性病历审查，以评估2008年至2017年TBP的治疗结果，并进行了系统的文献综述。分析纳入了定义为伴有髋-膝-踝（HKA）轴和干骺端-骨干角（MDA）偏差≥11度的病理性胫骨内翻的布朗特病病例。手术失败分为机械性失败和功能性失败。我们研究了患者和与植入物相关的特征，并将我们的结果与一项系统综述进行了比较。
在40例患者的61条肢体中，平均随访38个月，我们发现总体手术失败率为41%（25/61），机械性失败率为11%（7/61），在其他8项研究中分别为11%至100%（范围）和0%至50%（范围）。在单因素分析中，我们的手术失败组和未失败组之间的统计学比较显示，在畸形（P=0.001）、钢板材料（P=0.042）和肥胖（P=0.044）方面存在显著差异。在对个体风险因素进行调整后的多因素分析中，严重畸形使手术失败的几率增加1.2倍，钛制TBP使手术失败的几率增加5.9倍。所有7例机械性失败均涉及干骺端侧空心螺钉断裂。
大多数研究报告了布朗特病病例中TBP的高失败率。除了肥胖和畸形等与患者相关的风险因素外，钛制TBP似乎是失败的一个独立风险因素。实心螺钉对机械性失败有保护作用，但对功能性失败没有保护作用。总之，TBP在布朗特病中的疗效仍需证实，植入物设计可能需要重新评估。
III级——带有系统综述的回顾性比较研究。
