應用影像學指標與足底壓力分析探討微創手術治療足部畸形之臨床與生物力學效應

Abstract

足部畸形如扁平足（flatfoot）、拇趾外翻（hallux valgus, HV）及蹠骨內收（metatarsus adductus, MA）等，都是臨床上常見的足部問題，可能對患者的生活品質與行動能力造成顯著影響。微創手術在矯正足部畸形方面具有顯著優勢，相比傳統開放手術，微創手術不僅切口小、出血少、疼痛減輕，術後恢復快，而且對患者肢體的生物力學環境影響較小。 在臨床評估中，影像學指標和生物力學評估方法密不可分。影像學指標能夠清晰顯示骨骼結構和關節排列情況，是診斷和治療規劃的重要工具。生物力學評估，特別是足底壓力分析，則提供了動態的功能性數據，有助於了解手術對足部功能的影響。 本研究將結合影像學指標和足底壓力分析，全面探討微創手術治療足部畸形的臨床和生物力學效應，以期為臨床治療提供更為科學的評估和決策依據。具體的研究目的與結果如下： 目的一： 了解兒童扁平足接受微創矯正手術的術後長期結果與其影響因子。 本研究回溯性納入自2011到2015年在彰化秀傳醫院接受距下關節限制術的扁平足患者，分析手術前後的影像學指標與足底壓力分佈（根據Viladot分類），再分析其與功能表現的相關性。 研究共納入了19位病患的38隻腳，接受手術時的平均年齡為11±1.79歲，平均追蹤時間為10±1.4年。手術後所有的足部影像學指標均有顯著的改善，而足底壓力分佈（根據Viladot分類）有71%的足部分類為正常足型。功能表現依據AOFAS-hindfoot score和FAOS score，有82%的病患有Good to excellent的評分。而後根據ROC curve分析，手術前的talonavicular coverage angle 小於28.5度、Meary’s angle 小於19.5度、以及talar declination angle 小於37.5度可以預測較佳的長期術後功能表現。 目的二：了解拇趾外翻微創矯正手術對前足壓力的影響與其原因。 本研究前瞻性納入中度到重度拇趾外翻並接受MICA手術之患者，記錄手術前與術後三個月的Ｘ光影像及動態足底壓力分析（Footscan®, RSscan International, Olen, Belgium），再分析影像學指標與足底壓力變化的相關性。 研究共納入了25位患者的31隻腳，平均年齡為50.83±12.38歲。手術前後與拇趾外翻相關的影像學指標均有顯著的改善；而第一蹠骨的長度在術後有統計學顯著地縮短了2.3mm，雖然第二蹠骨的相對長度與側面的Meary’s angle並無統計學顯著的改變。足底壓力的部分，中央蹠骨區域的最大受力、最大壓力、累積受力、與累積壓力在手術前後都沒有統計學顯著的差異。反而是第一蹠骨與拇趾區域的壓力參數，在術後三個月有統計學顯著的降低。 目的三：了解拇趾外翻與蹠骨內收微創矯正手術對前足壓力的影響與其原因 研究前瞻性納入拇趾外翻併發蹠骨內收與蹠痛症（metatarsalgia）的患者，記錄手術前與術後六個月的Ｘ光影像及動態足底壓力分析，再分析術後Ｘ光影像學指標與足底壓力改變間的相關性。數據來自2021年8月至2023年7月期間由單一醫師治療的25名患者（25隻腳），平均年齡為50.1歲。影像學分析顯示，術後六個月HVA、IMA及MA均有顯著改善。而足底壓力評估顯示，術後六個月，第2至第4蹠骨區域的最大受力、峰值壓力、受力時間積分及壓力時間積分均顯著降低。

實驗設計：回溯性研究，前瞻式介入研究

Deformities of the foot such as flatfoot, hallux valgus (HV), and metatarsus adductus (MA) are common clinical foot problems that can significantly impact the quality of life and mobility of patients. Minimally invasive surgery (MIS) has significant advantages in correcting foot deformities. Compared to traditional open surgery, MIS offers smaller incisions, less bleeding, reduced pain, and faster recovery. It also causes less damage to surrounding muscles and other soft tissues, thereby having a smaller impact on the biomechanical environment of the limb. In clinical evaluations, imaging indicators and biomechanical assessment methods are closely related. Imaging indicators such as X-rays, CT scans, and MRI can clearly show the structure of bones and the alignment of joints, serving as important tools for diagnosis and treatment planning. Biomechanical assessment, especially plantar pressure analysis, an accurately measure the pressure distribution in different areas of the foot, reflecting changes in gait and weight-bearing conditions and providing important evidence for postoperative outcome evaluation. This study will combine imaging indicators and plantar pressure analysis to comprehensively explore the clinical and biomechanical effects of minimally invasive surgery for treating foot deformities, aiming to provide more scientific evaluation and decision-making basis for clinical treatment. The specific research aims are as follows: Aim 1: The aim 1 is to understand the long-term results of pediatric flat foot receiving minimally invasive correction and to determine the predictive factors. Conducted as a retrospective analysis, it included patients who underwent the procedure at Show-Chwan Memorial Hospital between 2011 and 2015. Correlations between radiographic measurements and plantar pressure distribution, as classified by the Viladot system, were also examined. A total of 19 patients (38 feet) participated in the study, with an average age of 11 ± 1.79 years at the time of surgery and a mean follow-up period of 10 ± 1.4 years. Postoperative radiographic parameters demonstrated significant improvements across all cases. Additionally, plantar pressure distribution analysis classified 71% of feet as having a normal foot type based on the Viladot classification. Functional outcomes, evaluated through the AOFAS hindfoot scale and FAOS, showed that 82% of participants achieved good to excellent results. Moreover, ROC curve analysis identified preoperative talonavicular coverage angles of less than 28.5°, Meary’s angles below 19.5°, and talar declination angles under 37.5° as predictors of more favorable long-term functional outcomes. Aim 2: The aim 2 is to understand the pedobarographic results of minimally invasive hallux valgus correction surgery and to determine its reasons. The research prospectively enrolled patients with moderate to severe hallux valgus treated with MICA. Radiographic data and dynamic plantar pressure measurements (Footscan®, RSscan International, Olen, Belgium) were collected preoperatively and three months postoperatively to explore correlations between imaging and pedobarographic parameters. A total of 25 patients (31 feet) were included, with a mean age of 50.83 ± 12.38 years. Radiographic parameters associated with hallux valgus, including HVA, IMA, DMAA, 1MTLHS, and LSG, showed statistically significant postoperative improvement. Additionally, the first metatarsal length was reduced by 2.3 mm following surgery. However, no significant changes were observed in the relative length of the second metatarsal or the lateral Meary’s angle. Regarding plantar pressure, central metatarsal regions showed no significant differences in maximum force, peak pressure, cumulative force, or cumulative pressure pre- and post-surgery. In contrast, pressure parameters in the first metatarsal and hallux regions demonstrated a significant decrease three months after surgery. Aim 3: The aim 3 is to understand the pedobarographic results of combined minimally invasive correction of hallux valgus and central metatarsals and to determine its reasons. This study prospectively included patients with hallux valgus, metatarsus adductus, and metatarsalgia, recording X-ray images and dynamic plantar pressure analysis (Footscan®, RSscan International, Olen, Belgium) preoperatively and six months postoperatively. The correlation between radiographic and pedobarographic parameters was then analyzed. Data were collected from 25 patients (25 feet) treated by a single surgeon between August 2021 and July 2023, with an average age of 50.1 years. Radiographic analysis revealed significant postoperative improvements in the hallux valgus angle (HVA), intermetatarsal angle (IMA), and metatarsus adductus angle (MA) six months after surgery. Pedobarographic evaluation showed reduced maximum force, peak pressure, force-time integral, and pressure-time integral in the second to fourth metatarsal regions six months after surgery.

Study Design: Retrospective cohort study, prospective cohort study.