Walker Janet L, Dueber David M, Powell Kenneth P, Stephenson Lindsay P, Scott Allison C, Lerman Joel A, Nossov Sarah B, Franklin Corinna C, Westberry David E
Shriners Children's and University of Kentucky Department of Orthopaedic Surgery and Sports Medicine.
University of Kentucky Department of Statistics, Lexington KY.
J Pediatr Orthop. 2023;43(5):e343-e349. doi: 10.1097/BPO.0000000000002373. Epub 2023 Mar 13.
Growth modulation in late-onset tibia vara (LOTV) has been reported to yield variable results. We hypothesized that parameters of deformity severity, skeletal maturity, and body weight could predict the odds of a successful outcome.
A retrospective review of tension band growth modulation for LOTV (onset ≥8 y) was performed at 7 centers. Tibial/overall limb deformity and hip/knee physeal maturity were assessed on preoperative anteroposterior standing lower-extremity digital radiographs. Tibial deformity change with first-time lateral tibial tension band plating (first LTTBP) was assessed by medial proximal tibia angle (MPTA). Effects of a growth modulation series (GMS) on overall limb alignment were assessed by mechanical tibiofemoral angle (mTFA) and included changes from implant removal, revision, reimplantation, subsequent growth, and femoral procedures during the study period. The successful outcome was defined as radiographic resolution of varus deformity or valgus overcorrection. Patient demographics, characteristics, maturity, deformity, and implant selections were assessed as outcome predictors using multiple logistic regression.
Fifty-four patients (76 limbs) had 84 LTTBP procedures and 29 femoral tension band procedures. For each 1-degree decrease in preoperative MPTA or 1-degree increase in preoperative mTFA the odds of their successful correction decreased by 26% in the first LTTBP and 6% by GMS, respectively, controlling for maturity. The change in odds of success for GMS assessed by mTFA was similar when controlling for weight. Closure of a proximal femoral physis decreased the odds of success for postoperative-MPTA by 91% with first LTTBP and for final-mTFA by 90% with GMS, controlling for preoperative deformity. Preoperative weight ≥100 kg decreased the odds of success for final-mTFA with GMS by 82%, controlling for preoperative mTFA. Age, sex, race/ethnicity, type of implant, and knee center peak value adjusted age (a method for bone age) were not predictive of outcome.
Resolution of varus alignment in LOTV using first LTTBP and GMS, as quantified by MPTA and mTFA, respectively, is negatively impacted by deformity magnitude, hip physeal closure, and/or body weight ≥100 kg. The presented table, utilizing these variables, is helpful in the prediction of the outcome of the first LTTBP and GMS. Even if complete correction is not predicted, growth modulation may still be appropriate to reduce deformity in high-risk patients.
Level III.
据报道，晚发性胫骨内翻（LOTV）的生长调节效果不一。我们假设畸形严重程度、骨骼成熟度和体重参数可以预测成功结果的几率。
对7个中心进行的LOTV（发病年龄≥8岁）张力带生长调节进行回顾性研究。术前站立位下肢前后位数字X线片评估胫骨/整个肢体畸形以及髋/膝骨骺成熟度。首次胫骨外侧张力带钢板固定术（首次LTTBP）后胫骨畸形变化通过胫骨近端内侧角（MPTA）评估。生长调节系列（GMS）对整个肢体对线的影响通过机械胫股角（mTFA）评估，包括研究期间取出植入物、翻修、重新植入、后续生长以及股骨手术引起的变化。成功结果定义为内翻畸形的X线片矫正或外翻过度矫正。使用多因素逻辑回归评估患者人口统计学、特征、成熟度、畸形和植入物选择作为结果预测因素。
54例患者（76条肢体）接受了84次LTTBP手术和29次股骨张力带手术。在控制成熟度的情况下，术前MPTA每降低1度或术前mTFA每增加1度，首次LTTBP成功矫正的几率分别降低26%，GMS降低6%。在控制体重的情况下，通过mTFA评估的GMS成功几率变化相似。股骨近端骨骺闭合使首次LTTBP术后MPTA成功几率降低91%，GMS使最终mTFA成功几率降低90%，同时控制术前畸形。术前体重≥100 kg使GMS最终mTFA成功几率降低82%，同时控制术前mTFA。年龄、性别、种族/民族、植入物类型和膝关节中心峰值调整年龄（一种骨龄计算方法）不能预测结果。
分别通过MPTA和mTFA量化，首次LTTBP和GMS治疗LOTV内翻对线矫正受畸形程度、髋骨骺闭合和/或体重≥100 kg的负面影响。利用这些变量列出的表格有助于预测首次LTTBP和GMS的结果。即使无法预测完全矫正，生长调节对于降低高危患者的畸形可能仍适用。
III级。
