In rehabilitation medicine it has repeatedly been noted that so-called chronic ankle instability - spraining the same ankle again and again - is hard to explain by muscle weakness alone. Reduced sensory function in the foot and ankle plays a part.

The ankle joint contains receptors that sense position and motion. A severe sprain damages not only ligaments but these receptors, and during recovery sensory signals may not be transmitted as precisely as before.

The consequence is a delay in adjusting the angle of the foot at the moment it meets the ground. Even with adequate strength, a lag in timing can end in another sprain - the essence of the argument.

Balance training is what rehabilitation practice commonly recommends: standing on one leg, holding balance with eyes closed, or standing on an unstable surface, all of which train sensation and reaction speed together.

Where pain or swelling remains, however, seeing a clinician comes before starting exercise, since the treatment required depends on the degree of ligament damage.

This article summarizes general health information and does not substitute for diagnosis or treatment. Where symptoms recur or worsen, an orthopedic or rehabilitation consultation is warranted.