By Jonathan Blood-Smyth
In the raising up on tiptoe manoeuvre we should observe that as the calf muscle exerts its power to raise the body weight over the metatarsal heads, the heel should adopt a slight inward slant. If the tibialis posterior tendon is not functioning well this inward movement of the heel does not happen and patients may find the action difficult, painful or not possible. The physiotherapist will next check the foot up on the bed and palpate around the insertion of the tendon for pain, tenderness and swelling. Then the foot will be held in an inwards and foot down position and the patient asked to hold it there as the physio applies resistance to test the muscle power.
The physiotherapist will palpate all along the tendon as its strength is being assessed to check it is not ruptured or deficient and then straighten the knee and measure how much dorsiflexion is achievable, typically twenty degrees or so. If the deformity has been present over time and the foot held in an out and down position then this movement can be lost as a tight contracture develops in the joints. This can also occur in the forefoot joints and the physio will move down to check this after the ankle area. Treatment may be appropriate if the patient is having difficulty with walking, managing shoes, pain and deformity.
If the flat foot is painless and the person can walk well then normal shoes with or without insoles will suffice. Conservative management of posterior tibial tendon dysfunction involves resting, immobilisation, anti-inflammatories, physiotherapy and bracing or orthotics. This might be sufficient especially in elderly people as they do not put large forces through the area and may be less suitable for operative intervention. The initial stage of this condition presents primarily with pain, with acute inflammation of the tendon managed in plaster of Paris cast for a few weeks, which can be a weight bearing cast if walking is comfortable.
Orthotics can then be used to support the foot once the acute stage has settled and physiotherapy employed to stretch out any tight joint movements and strengthen the muscle groups. As the dysfunction proceeds and the foot deformity is flexible but painful it may be necessary to control the motion of the hindfoot more closely using a ankle-foot orthosis (AFO) of some kind. Later if the deformity becomes more rigid then individually moulded braces, perhaps extending to the knee or beyond, can be employed. This kind of treatment is for patients who are not physically very active, with operative treatment held in reserve.
In the earlier stages of more acute dysfunction of the tendon surgical management entails the tendon sheath being opened to release it, a debridement (cleaning up) of the local area and repairs to the body of the tendon. After operation the patient is typically three weeks or so in a below knee cast, with this operation performed in the hope of stopping progression of the condition. More severe foot dysfunction forces the surgeon to choose from a very large number of operative options. There is no agreed surgical management of this phase and a good outcome is hard to ensure.
A ruptured tendon can be trimmed and an end-to-end repair performed, or if avulsed from its bony attachment this can be re-attached to the navicular bone. In more complex surgical procedures the tendons of other local muscles can be used as reinforcements to the posterior tibial muscle tendon, so restoring some of its function. The bony anatomy can also be reshaped by performing an osteotomy and realigning the joint relationships, such an operation on the calcaneum or heel bone aimed at restoring alignment, reducing forces through the plantar and spring ligaments and permitting the soft tissues to endure less stress.
The main aim of surgery is to produce a foot which can adapt flat to the ground, take normal footwear and be without pain. It is possible for surgery to cause an over correction or an under correction in foot posture and surgeons must take great care in aligning the various aspects of a more normal foot posture. The aim of surgery in the beginning is to halt progress towards potential tendon rupture.
Jonathan Blood Smyth is the Superintendent of Physiotherapy at an NHS hospital in the South-West of the UK. He writes articles about back pain, neck pain, and injury management. If you are looking for physiotherapists in Sheffield visit his website.
This page created 27 May 2012 22:11
Last updated 27 May 2012 22:15