This is most commonly due to dysfunction of the tibialis posterior tendon.
Other causes include arthritis, ligament failure and trauma.

Acquired Flat Foot DeformityTibialis Posterior runs down the inside of the ankle to insert in the navicular bone in the foot.
Tibialis posterior is important in maintaining the arch of your foot and provides support during walking.

Problems in this tendon are usually degenerative.

They are more commonly seen in women, age >50, diabetics, and patients with inflammatory arthritis.

This tendon may become inflamed, stretched or torn resulting in pain and progressive loss of the arch.


What are the symptoms?

  • Pain and swelling over the inside of the ankle
  • Progressive loss of the arch and development of a flat foot
  • Pain on the outside of the ankle or foot
  • Weakness and an inability to tiptoe

Stages of Tibialis Posterior Dysfunction:

I. Inflamed tendon with normal strength

II. Degenerative elongated tendon with weakness and development of a flat foot

III. Torn tendon with a rigid flatfoot deformity. Can develop arthritis

IV. Similar to III but with associated ankle arthritis

What is the non operative treatment?

  • Pain relief
  • Weight loss
  • Activity modification
  • Stage I and II
    • Medial arch support with a medial heel wedge
    • Physiotherapy for strengthening
  • Stage III and IV
    • A rigid ankle foot orthosis
    • Steroid injections may be used for diagnostic purposes but do not result in healing of the tendon. They may be helpful for other causes of flat foot deformity.

What is the surgical treatment?

Surgical treatment is dependent on the stage, extent of the deformity and the presence of arthritis.

Surgery is individualized to your foot and may include the following:

  • Achilles tendon lengthening
  • Calcaneus osteotomy to realign the heel
  • Lateral column lengthening of calcaneus
  • Tibialis posterior tendon debridement
  • Tendon transfer from lesser toes to reconstruct tibialis posterior
  • Spring ligament reconstruction
  • Correction of the midfoot deformity with fusion or osteotomy
  • Subtalar joint fusion
  • Triple fusion

Will the operation be painful?

Your operation will usually be done under general anaesthetic.

To provide ongoing pain relief your Anaesthetist may perform a nerve block which numbs the foot for 8-16 hours. So when you wake up you will have minimal pain.

As the block wears off you will be given oral pain relief.


What does the rehabilitation involve?

  • 2 nights in hospital
  • 2 weeks rest and elevation of the foot in a cast non weightbearing
  • 4 weeks in a boot non weightbearing
  • 6 weeks in a boot progressively weightbearing
  • Physiotherapy from 6 weeks
  • At 3 months managing most daily activities in a shoe with an arch support
  • By 6 months back to recreational activities
  • When swelling resolves at 6-9 months a permanent custom orthotic is required
  • Final result at 1 year

How long will I be off work?

This is dependent upon your occupation

  • Seated job 3-4 weeks
  • Standing / Walking job 8-12weeks
  • Heavy lifting job 4-6 months

When can I drive?

  • If you have a manual car you will be unable to drive for 12 weeks
  • If you have an automatic car you can drive after 2 weeks if you have your left foot corrected and 12 weeks if your right foot has been corrected.

What are the risks of the procedure?

General risks of surgery

  • Infection
  • Wound healing problems
  • Nerve injury and scar sensitivity
  • Incomplete resolution of your symptoms
  • Blood clots to the leg
  • Anaesthetic problems

Specific to flat foot correction surgery

  • Incomplete correction of deformity
  • Stiffness
  • Incomplete relief of pain
  • Recurrence of deformity
  • Nonunion of the osteotomies
  • Metal implant irritation requiring removal

Specific for joint fusion

  • Non union of the fusion
  • Malunion of the fusion

This information is an overview of the management of an acquired flat foot deformity and is not all inclusive.

If you have any questions please contact Mr Curry’s rooms on (03) 99286560