A computational modeling framework to assess the influence of carbon fiber orthosis use on ankle function and contact mechanics: A pilot study.

The computational framework successfully estimated physiologically reasonable secondary kinematics, muscle forces, and cartilage contact stresses concurrently during gait simulation.

• Simulations achieved low marker error (< 20 mm RMS) and small residual forces and moments, indicating strong dynamic consistency.
• Two healthy adults participated (height: 1.74 m, 1.89 m; mass: 74.5 kg, 92.5 kg).
• Four orthosis walking conditions were simulated for each subject.
• Results were compared to previous findings to verify performance of the framework.

Weight bearing CT was used to integrate subject-specific ankle joint models into the musculoskeletal gait simulation framework.

• The framework was driven by whole-body gait kinematics and ground reaction kinetics.
• The concurrent simulation investigated how custom dynamic orthosis stiffness influences plantarflexor muscle force, joint contact force, and tibiotalar contact stress during stance.
• Subject-specific ankle joint models were derived from weight bearing CT imaging.
• This is described as a pilot study with two healthy adult participants.

Custom dynamic carbon fiber orthoses were simulated as a potential non-invasive means to decrease plantarflexor muscle force and ankle contact stress.

• Articular fractures of the distal tibia often lead to post-traumatic osteoarthritis, providing clinical motivation for the framework.
• The framework assessed the influence of carbon fiber orthosis stiffness on ankle function and contact mechanics.
• The rationale is that reducing plantarflexor muscle force would in turn reduce contact stress to preferentially offload the ankle.
• Four orthosis stiffness conditions were simulated and compared across participants.

The validated framework is designed to inform future interventional trials to mitigate the effects of traumatic fracture by enabling systematic examination of orthosis design effects on joint and articular contact forces.

• The framework is presented as suitably validated based on pilot results.
• It is intended to support examination of orthosis design parameters on joint-level outcomes.
• The clinical target population is patients with post-traumatic osteoarthritis following distal tibia articular fractures.
• Precisely restoring joint surface to lower contact stress is described as 'a proven tenet of treatment,' but incongruity often persists after operative fracture reduction.