Hospital for Special Surgery, New York, NY, USA.
Department of Orthopedic Foot and Ankle Surgery, University of Iowa School of Medicine, Iowa City, IA, USA.
Foot Ankle Int. 2020 Aug;41(8):930-936. doi: 10.1177/1071100720925423. Epub 2020 Jun 8.
Assessment of operative correction of adult-acquired flatfoot deformity (AAFD) has been traditionally performed by clinical evaluation and conventional radiographic imaging. Previously, a 3-dimensional biometric weightbearing computed tomography (WBCT) tool, the foot ankle offset (FAO), has been developed and validated in assessing hindfoot alignment. The purpose of this study was to investigate the role of FAO in evaluating operative deformity correction in AAFD.
In this prospective comparative study, 19 adult patients (20 feet) with stage II (flexible) flatfoot deformity underwent preoperative and postoperative standing WBCT examination at mean 19 months (range, 6-24) after surgery. Three-dimensional coordinates of the foot tripod and center of the ankle joint were acquired by 2 independent and blinded observers. These coordinates were used to calculate the FAO using dedicated software, and subsequently compared pre- and postoperatively. The FAO is a previously validated biometric measurement that represents centering of the foot tripod as well as hindfoot alignment, with a normal mean FAO of 2.3% ± 2.9%. In addition, Patient Reported Outcomes Measurement Information System (PROMIS) clinical outcomes scores were compared pre- and postoperatively with a mean follow-up of 22.6 months (range, 14-37).
There was significant correction of flatfoot deformity from a mean preoperative FAO of 9.8% to a mean postoperative value of 1.3% ( < .001). Additionally, there was statistically significant improvement in all PROMIS domains ( < .05), except depression, at an average follow-up of 22.6 months. Spring ligament reconstruction was the only procedure associated with a significant correction in FAO ( = .0064).
The FAO was a reliable and sensitive tool that was used to evaluate preoperative deformity as well as postoperative correction, with patients demonstrating both significant improvement in FAO as well as patient-reported outcomes. These findings demonstrate the role for biometric 3-dimensional WBCT imaging in assessing operative correction after flatfoot reconstruction, as well as the potential role for operative planning to address preoperative deformity.
Level II, prospective comparative study.
成人获得性扁平足畸形（AAFD）的手术矫正评估传统上通过临床评估和常规影像学检查进行。先前，已经开发并验证了一种 3 维生物计量负重计算机断层扫描（WBCT）工具，即足踝偏移量（FAO），用于评估后足对线。本研究的目的是探讨 FAO 在评估 AAFD 手术矫正中的作用。
在这项前瞻性对比研究中，19 名成人患者（20 只脚）患有 II 期（柔韧性）扁平足畸形，在手术后平均 19 个月（6-24 个月）进行了术前和术后站立 WBCT 检查。通过 2 名独立和盲目的观察者获取足部三脚架的 3 维坐标和踝关节中心。使用专用软件计算 FAO，然后比较术前和术后的值。FAO 是一种先前经过验证的生物计量测量方法，代表足部三脚架的中心以及后足对线，正常的平均 FAO 为 2.3%±2.9%。此外，与平均随访 22.6 个月（14-37 个月）相比，比较了术前和术后的患者报告的结局测量信息系统（PROMIS）临床结局评分。
扁平足畸形从术前平均 FAO9.8%显著矫正至术后平均 1.3%（<0.001）。此外，除抑郁外，所有 PROMIS 领域均有统计学显著改善（<0.05）。在平均随访 22.6 个月时，只有跟腱重建与 FAO 的显著矫正相关（=0.0064）。
FAO 是一种可靠且敏感的工具，用于评估术前畸形和术后矫正，患者在 FAO 以及患者报告的结果方面均显示出显著改善。这些发现证明了生物计量 3 维 WBCT 成像在评估扁平足重建后的手术矫正中的作用，以及手术计划在解决术前畸形中的潜在作用。
II 级，前瞻性对比研究。
