The dysfunction and function of the arch of the foot is critical to normal walking and as well as running gait and biomechanics. The stability of the mid-foot ( arch ) of the foot is looked after by a number of things, for example the shape of the bones, the ligaments, the muscles and the plantar fascia. One of many major muscles in the functional stability of the arch of the feet are the posterior tibial muscle. This is a powerful muscle that is in the leg. The tendon of this muscle passes around the inside of the ankle joint and attaches underneath the bones that comprise the mid-part of the arch of the foot, so this particular muscle is so important for supporting the mid-foot ( arch ). In some people, this muscle appears to lose it capability to stabilize the foot, causing a condition referred to as Posterior tibial tendon dysfunction or adult acquired flat foot.
This condition usually starts off with a mild discomfort in the midfoot or medial side of the ankle joint and the arch of the foot gradually collapses and the rearfoot rolls inwards (pronates). This is all as a result of the muscle being unable to do its job adequately. If treatment is not started, then the pain and disability progresses. In its end stages it can be very disabling and painful. It gradually has a considerable effect on quality of life and the ability to walk. It is quite exhausting because a lot of energy is needed to walk with this problem.
Since the long term outcomes of this problem can be so debilitating, it is important that it must be caught as quickly as possible and treatment started. The lengthier the delay the more difficult it is to manage. In the early stages, the only real satisfactory treatment usually are very firm or rigid foot orthoses. They have to be firm as the forces that are lowering the arch are so great that they must be resisted. A softer support will be flattened. A high top hiking or basketball like shoe or boot can be helpful at stabilising the ankle joint. If this isn't satisfactory then more complicated ankle braces will be the next step. If this fails or the therapy is started far too late, then surgical intervention is actually the only good enough intervention at this late stage.