de Cesar Netto Cesar, Barbachan Mansur Nacime Salomão, Talaski Grayson, Jasper Ryan P, Schmidt Eli, de Carvalho Kepler Alencar Mendes, Dibbern Kevin, Lintz Francois, Ellis Scott J, Anderson Donald Dean
Department of Orthopedic Surgery, Duke University, Durham, North Carolina.
Department of Orthopedics and Rehabilitation, University of Iowa, Iowa City, Iowa.
J Bone Joint Surg Am. 2025 Sep 17;107(18):2060-2068. doi: 10.2106/JBJS.24.01619. Epub 2025 Aug 4.
Flatfoot, or pes planus, is a common anatomical variation marked by a reduced or absent longitudinal arch. Although it is often considered benign, the condition can progress to progressive collapsing foot deformity (PCFD), a debilitating pathology. This study aimed to identify imaging biomarkers that distinguish asymptomatic flatfoot from PCFD by comparing 3D measurements among normally aligned feet, asymptomatic flatfeet, and feet with PCFD.
A prospective, comparative, and controlled study was conducted on 561 feet in 475 subjects: 88 control subjects with 98 normally aligned feet, 66 control subjects with 132 asymptomatic flatfeet, and 321 patients with 331 feet with symptomatic PCFD. Bilateral weight-bearing computed tomography (WBCT) scans were performed, and various 3D measurements were analyzed, focusing on hindfoot valgus (Class A deformity), midfoot and/or forefoot abduction (Class B), arch collapse (Class C), and peritalar subluxation (PTS) (Class D). Statistical analysis, including multivariable nominal regression, was used to identify significant predictors of symptoms.
Progressive increases in Class A, B, and C deformity parameters were observed from normally aligned feet to asymptomatic flatfeet and finally to feet with PCFD. Significant differences in PTS (Class D deformity) were found only in the comparison between the feet with PCFD and the control groups, with reduced joint coverage and increased sinus tarsi coverage, indicating extra-articular impingement. Multivariable analysis identified the minimum sinus tarsi distance as the strongest predictor of symptoms, with a threshold of 1.9 mm best distinguishing symptomatic from asymptomatic feet.
This study demonstrated that although hindfoot valgus, midfoot and/or forefoot abduction, and arch collapse deformities progressively increase from normal alignment to PCFD, significant subtalar joint subluxation and sinus tarsi impingement were unique to symptomatic PCFD. These findings suggest that PTS can serve as a crucial biomarker for diagnosing pathologic flatfoot (PCFD) and differentiating it from asymptomatic flatfoot. Future research should explore the predictive value of PTS biomarkers in identifying flatfoot at high risk for collapse and their impact on clinical management and surgical decision-making.
Prognostic Level II . See Instructions for Authors for a complete description of levels of evidence.
扁平足，即平足症，是一种常见的解剖变异，其特征为纵弓降低或消失。尽管通常被认为是良性的，但这种情况可能会发展为进行性塌陷足畸形（PCFD），这是一种使人衰弱的病理状况。本研究旨在通过比较正常排列足、无症状扁平足和患有PCFD的足之间的三维测量结果，确定区分无症状扁平足和PCFD的影像学生物标志物。
对475名受试者的561只足进行了一项前瞻性、对比性和对照性研究：88名对照受试者有98只正常排列的足，66名对照受试者有132只无症状扁平足，321名患者有331只患有症状性PCFD的足。进行了双侧负重计算机断层扫描（WBCT），并分析了各种三维测量结果，重点关注后足外翻（A类畸形）、中足和/或前足外展（B类）、足弓塌陷（C类）和距下关节半脱位（PTS）（D类）。使用包括多变量名义回归在内的统计分析来确定症状的显著预测因素。
从正常排列的足到无症状扁平足，最后到患有PCFD的足，观察到A、B和C类畸形参数逐渐增加。仅在患有PCFD的足与对照组之间的比较中发现PTS（D类畸形）存在显著差异，关节覆盖减少，跗骨窦覆盖增加，表明存在关节外撞击。多变量分析确定跗骨窦最小距离是症状的最强预测因素，阈值为1.9 mm时最能区分有症状和无症状的足。
本研究表明，尽管后足外翻、中足和/或前足外展以及足弓塌陷畸形从正常排列到PCFD逐渐增加，但显著的距下关节半脱位和跗骨窦撞击是有症状的PCFD所特有的。这些发现表明，PTS可作为诊断病理性扁平足（PCFD）并将其与无症状扁平足区分开来的关键生物标志物。未来的研究应探讨PTS生物标志物在识别有塌陷高风险的扁平足方面的预测价值及其对临床管理和手术决策的影响。
预后II级。有关证据水平的完整描述，请参阅作者指南。
