MODIFYING MIDSOLE STIFFNESS of BASKETBALL FOOTWEAR AFFECTS FOOT and ANKLE BIOMECHANICS

Abstract

Background: There is a growing incidence of foot injuries in basketball, which may be from the sport's repetitive, forceful multi-directional demands. Modifying midsole stiffness of the basketball shoe has been reported to alter ankle motion and plantar forces to reduce the risk of injury; however, the effects on anatomical, in-shoe foot (metatarsal), motion is not well understood. Purpose:The purpose of this study was to identify differences in foot and ankle biomechanics between basketball shoes with differing midsole stiffness values during single-leg jump landings. It was hypothesized that a stiffer midsole would elicit lower 1 st metatarsophalangeal joint (MTPJ) dorsiflexion angles, higher ankle dorsiflexion angles, and higher plantar forces and relative loading in the distal foot. Study Design: Experimental cross-sectional study.Methods: Twenty high school and collegiate-aged basketball players performed a single-leg side drop jump and a single-leg cross drop jump in a pair of standard basketball shoes and a pair of shoes modified with a fiberglass plate to increase midsole stiffness. Three-dimensional motion analysis and flexible insoles quantified foot and ankle kinematics and plantar force distribution, respectively. Separate 2 (footwear) x 2 (task) repeated measures ANOVA models were used to analyze differences in 1) ankle kinematics, 2) 1 st metatarsophalangeal kinematics, 3) maximal regional plantar forces, and 4) relative load. Results:The stiffer shoe elicited decreased peak ankle plantarflexion (mean difference=5.8°, p=0.01) and eversion (mean difference=6.6°, p=0.03) and increased peak ankle dorsiflexion angles (mean difference=5.0°, p=0.008) but no differences were observed in 1 st MTPJ motion (p>0.05). The stiffer shoe also resulted in lower peak plantar forces (mean difference=24.2N, p=0.004) and relative load (mean difference=1.9%, p=0.001) under the lesser toes. Conclusions:Altering the midsole stiffness in basketball shoes did not reduce motion at the MTPJ, indicating that added stiffness may reduce shoe motion, but does not reduce in-shoe anatomical motion. Instead, a stiffer midsole elicits other changes, including additional ankle joint motion and a reduction in plantar forces under the lesser toes. Collectively, this indicates that clinicians need to account for unintended compensations that can occur throughout the kinetic chain when altering a shoe property to alleviate a musculoskeletal injury.

The Use of Developing Technology in Sports

“…Technology has a very important role to play in injury prevention and rehabilitation for basketball players. Biomechanical analyses, pedabarographic analyses, and motion capture technology and wearable sensors, as one of the critical sensing components, can be used for human medical diagnosis, medical monitoring (Dai et al, 2022;Lee et al, 2019;Luo et al, 2020;Aydos, 2023;Pekel and Aydos, 2022), helping to identify risky movement patterns, enabling players and medical staff to address potential disability issues before they escalate (Castro et al, 2008;Taylor et al, 2019). From cryotherapy rooms to wearable recovery devices, technology plays a crucial role in optimizing players' recovery, reducing downtime and ensuring peak performance (Banfi et al, 2010;Jinnah et al, 2019).…”