Abstract
BACKGROUND: Research on Morton's neuroma (MN) has seen limited advancement in recent years, leading to a lack of quantitative studies on the foot patterns of affected patients. Given the various age-related factors influencing foot bone deformities in elderly patients with MN, conclusions regarding their foot patterns remain uncertain. This study aims to investigate the plantar load distributions and foot postures in collegiate athletes diagnosed with MN. METHODS: A cross-sectional study was conducted involving 36 asymptomatic volunteers and 45 participants diagnosed with MN. The JC Mat optical plantar load analyzer was employed to assess arch index (AI), plantar load distributions, center of gravity and hallux angles during static stances, while also evaluating rearfoot postural alignment. RESULTS: Participants with MN demonstrated symmetrical and normal AI values. Left-foot MN participants exhibited significantly higher plantar loads at the lateral metatarsal of the left foot (p = 0.003) and the medial heels of both feet (left foot, p = 0.004; right foot, p = 0.003), while those with right-foot MN experienced increased loads primarily at the lateral metatarsals of both feet (left foot, p = 0.009; right foot, p = 0.000) and the medial longitudinal arch of the left foot (p = 0.021). Both MN groups exhibited a compensatory shift in the center of gravity toward the asymptomatic foot. Furthermore, left-foot MN participants showed increased hallux valgus angles (p = 0.001) and rearfoot varus angles (p = 0.043) in the affected foot, while right-foot MN participants exhibited increased hallux valgus angles (p = 0.021) in the affected foot and rearfoot varus angles in both feet (left foot, p = 0.033; right foot, p = 0.049). CONCLUSION: Taiwanese collegiate athletes with MN exhibited normal arches, with plantar loads primarily distributed at the lateral metatarsals of both feet. The affected foot displayed hallux valgus and rearfoot varus. These findings underscore a compensatory shift in the center of gravity toward the asymptomatic foot and a potential link between hallux valgus, rearfoot varus, and the MN condition. The results offer insights into biomechanical adaptations and potential targets for clinical interventions in MN management, suggesting that hallux valgus may serve as a visible predictive marker for MN-related pathological changes, which may facilitate early diagnosis and inform personalized treatment strategies. TRIAL REGISTRATION: This study was registered at the UK's Clinical Study Registry. (Trial Registration Number: ISRCTN17467973; Date: 09/01/2025; https://www.isrctn.com/ISRCTN17467973 ).