Extremely painful tibialis sheen on long or fast walk. i already wear custom orthoses with arch sup &metatarsal pad for flat foot and metatarsal pain?

Leg muscle pain: When you walk you have to lift your foot and toes to clear the ground. This exercises the tibialis anterior and anterior muscle compartment. In some people this can result in pain due to muscle swelling. Therapy and strengthening exercises can help. In some cases of what is called 'exertional compartment sydrome' surgery is necessary for pain relief.

CLARIFICATION: "Tibialis sheen?" Do you mean tib. posterior or tib. anterior? I will speak to the tibialis posterior tendon. If this is your diagnosed problem, I always utIlize an MRI to look at the tendon. Then, orthoses, bracing, or a cast can be tried depending upon the integrity of the tendon. Therapy is another option. If all these fail, surgery can be discussed. I have pretty good success with a brace.