Practical and research implications
This case report has the following implications: (1) the lack of push-off after toe amputation should be carefully observed, as this may cause increased contralateral limb loading and subsequent musculoskeletal comorbidities. (2) Understanding the musculoskeletal comorbidities in the contralateral limb after toe amputation is an interesting future direction to determine the relationship between the former and increased contralateral limb loading. In the future studies, careful consideration for confounders, including preexisting arthritis in multiple joints and cardiovascular status is warranted. Since we cannot rule out that biomechanical changes in ipsilateral limb are consequence of those in contralateral limb, determining the causal relationship is also needed. Once the causal relationship of the lacked push-off in ipsilateral limb and mechanical overloading with subsequent comorbidities in contralateral limb is verified, rehabilitation and gait retraining are of interest to improve the production capacity of plantar flexor torque during the ipsilateral terminal stance20.