Flat Foot Correction (Posterior Tibial Tendon Dysfunction)

Posterior tibial tendon dysfunction is a very common problem. It occurs when the posterior tibial tendon becomes inflamed or torn. As a result, the tendon may not be able to provide stability and support for the arch of the foot, resulting in flatfoot. This operation is for ankle pains due to flat feet (pes planus). The pain is due to inflammation of the posterior tibial tendon, this muscle / tendon supports the arch of the foot. The inflammation allows the tendon to stretch or tear, causing or exacerbating a flat foot deformity. As the deformity progresses, it causes arthritis of the hindfoot joints and pain at the outside of the ankle. This type of operation is used before the deformity has progressed to arthritis.

The surgery involves a transfer of the flexor digitorum longus tendon (FDL) into the navicular bone, to take the place of the diseased tendon. The operation is performed through an incision running from the inside ankle to the arch of the foot. It is combined with an osteotomy (cut) of the Os Calcis (heel bone) to reinforce the deformity correction. The osteotomy is performed through an incision on the outside of the heel and fixed with a screw.

Risks of surgery

Swelling

Initially the foot will be very swollen and needs elevating. The swelling will disperse over the following weeks & months but will still be apparent at 6-9 months.

Infection

This is the biggest risk with this type of surgery. You will be given intravenous antibiotics to prevent against it. The best way to reduce your chances of acquiring an infection is to keep the foot elevated for 10 days. If there is an infection, it may resolve with a course of antibiotics.

Nerve Damage

Alongside the incisions are two nerves – the saphenous and the sural nerves. They supply sensation to the sides of the foot and toes. They may become damaged during the surgery and this will leave a patch of numbness at the sides of the foot. This numbness may be temporary or permanent. There is approximately a 10-15% of this happening.

Failure to relieve all symptoms

The results from this surgery are good. Over 90% of people have good relief of their pain for more than 5 years. In 50%, there is some recurrence of the deformity, but without pain.

Recovery from surgery

After surgery, your leg will be immobilised in a backslab (half plaster) for 2 weeks. Elevation of the foot (above the pelvis) for the first 10 days is vitally important to prevent infection. Naturally, small periods of walking and standing are necessary, but no weight must be taken through this leg for 6 weeks.

After 2 weeks the backslab will be removed and the stitches taken out, here in clinic. Another non-weight bearing plaster is applied for a further 4 weeks. At this stage you will be reviewed in clinic and the plaster cast is removed. You can begin walking now and physiotherapy is started.

You will be reviewed again at 3 months following surgery, with x-rays.

Activity and time off work

In general, up to 4 weeks off work is required for sedentary posts. 12 weeks for standing or walking posts. 16 weeks for manual / labour intensive posts.

Follow up

  • 2 weeks for removal of sutures & COP
  • 6 weeks in Mr Rosenfeld's clinic
    • Removal of PoP
    • AP & Lateral X-rays of Ankle
    • Mobilise FWB
  • 3 months for final assessment if no complications