Why does callus form?
Callus develops when skin is exposed to excessive pressure or friction. The body wants to protect itself and therefore builds up a protective layer. Whilst sometimes this is related to footwear rubbing over bony prominences or deformities, it can also indicate an underlying complication with your foot mechanics (movement).
What could that indicate?
Calluses formed by abnormal foot biomechanics are generally showing us that forces within the foot during walking are unbalanced. The position of the calluses can indicate exactly how your gait is compromised, which is best understood by reviewing how your feet are designed to move with every step you take every day.
During a normal gait, the heel strikes the ground first and the foot structure helps absorb shock. The foot then immediately turns into a flexible structure as it adapts to the ground beneath it, then again becomes a rigid lever to efficiently push you forward to take your next step. Your big toe is designed to take most of your body weight, as you propel forward. Normal gaits typically don’t lead to painful callus formation.
An abnormal gait, often caused by disturbances in the bones and joints of your foot, can cause undue pressure and irritation on specific areas of your foot and the development of calluses. Any disturbances in 'normal' gait above the foot i.e. at the knee or hip will cause foot mechanics to alter and symptoms arise.
Typical Callus Formations
This illustration shows many of the common patterns a podiatrist will see on a daily basis in their practice. We assess the presenting pattern and this can be an indicator of abnormal mechanics that may need addressing .
For example: foot type J would indicate that the big toe joint is not working efficiently at propulsion and causing overload to end of the first toe and the second metatarsal. Addressing this function will ultimately help reduce this callus formation and reduce any pain to these highlighted areas.
All ages are susceptible to callus formation and there is always a cause. Your Podiatrist is the best person to assess the cause and come up with a plan to address this and ultimately allow you to walk pain-free and callus free.