Department of Orthopedics and Rehabilitation, University of Iowa, Iowa City, IA, USA.
Federal University of São Paulo, São Paulo, Brazil.
Foot Ankle Int. 2021 Jun;42(6):768-775. doi: 10.1177/1071100720982907. Epub 2021 Jan 29.
Lateral overload in progressive collapsing foot deformity (PCFD) takes place as hindfoot valgus, peritalar subluxation, and valgus instability of the ankle increase. Fibular strain due to chronic lateral impingement may lead to distraction forces over the distal tibiofibular syndesmosis (DTFS). This study aimed to assess and correlate the severity of the foot and ankle offset (FAO) as a marker of progressive PCFD with the amount of DTFS widening and to compare it to controls.
In this case-control study, 62 symptomatic patients with PCFD and 29 controls who underwent standing weightbearing computed tomography (WBCT) examination were included. Two fellowship-trained blinded orthopedic foot and ankle surgeons performed FAO (%) and DTFS area measurements (mm). DTFS was assessed semiautomatically on axial-plane WBCT images, 1 cm proximal to the apex of the tibial plafond. Values were compared between patients with PCFD and controls, and Spearman correlation between FAO and DTFS area measurements was assessed. values of less than .05 were considered significant.
Patients with PCFD demonstrated significantly increased FAO and DTFS measurements in comparison to controls. A mean difference of 6.9% ( < .001) in FAO and 10.4 mm ( = .026) in DTFS was observed. A significant but weak correlation was identified between the variables, with a Þ of 0.22 ( = .03). A partition predictive model demonstrated that DTFS area measurements were highest when FAO values were between 7% and 9.3%, with mean (SD) values of 92.7 (22.4) mm.
To our knowledge, this was the first study to assess syndesmotic widening in patients with PCFD. We found patients with PCFD to demonstrate increased DTFS area measurements compared to controls, with a mean difference of approximately 10 mm. A significantly weak positive correlation was found between FAO and DTFS area measurements, with the highest syndesmotic widening occurring when FAO values were between 7% and 9.3%. Our study findings suggest that chronic lateral impingement in patients with PCFD can result in a negative biomechanical impact on syndesmotic alignment, with increased DTFS stress and subsequent widening.
Level III, retrospective comparative study.
进行性塌陷足畸形（PCFD）中出现的外侧负荷增加会导致后足外翻、距下关节半脱位和踝关节外侧不稳定。由于慢性外侧撞击导致的腓骨应变可能导致远端胫腓联合（DTFS）上的分散力。本研究旨在评估和关联作为进行性 PCFD 标志物的足部和踝关节偏移（FAO）的严重程度与 DTFS 增宽的程度，并将其与对照组进行比较。
在这项病例对照研究中，纳入了 62 名患有 PCFD 的症状性患者和 29 名接受站立负重计算机断层扫描（WBCT）检查的对照组。两名具有 fellowship培训的盲法足踝矫形外科医生进行 FAO（%）和 DTFS 面积测量（mm）。在轴向 WBCT 图像上，在距胫骨平台顶点 1cm 处对 DTFS 进行半自动评估。将患者与对照组之间的 FAO 和 DTFS 面积测量值进行比较，并评估 FAO 与 DTFS 面积测量值之间的 Spearman 相关性。小于.05 的 值被认为具有统计学意义。
与对照组相比，患有 PCFD 的患者的 FAO 和 DTFS 测量值显著增加。FAO 的平均差异为 6.9%（ <.001），DTFS 为 10.4mm（ =.026）。观察到变量之间存在显著但较弱的相关性，Þ 为 0.22（ =.03）。分区预测模型表明，当 FAO 值在 7%至 9.3%之间时，DTFS 面积测量值最高，平均值（标准差）为 92.7（22.4）mm。
据我们所知，这是第一项评估 PCFD 患者的联合增宽的研究。我们发现，与对照组相比，患有 PCFD 的患者的 DTFS 面积测量值增加，平均差异约为 10mm。FAO 和 DTFS 面积测量值之间存在显著的弱正相关，当 FAO 值在 7%至 9.3%之间时，联合增宽最大。我们的研究结果表明，PCFD 患者的慢性外侧撞击可能会对联合对线产生负向生物力学影响，导致 DTFS 应力增加和随后的增宽。
III 级，回顾性比较研究。
