Adult Acquired Flatfoot

Adult acquired flatfoot is thought to be due to dysfunction of the tibialis posterior tendon which runs behind the ankle joint into the foot on the medial or inside of the foot and ankle. It is often not associated with a traumatic event, but related more to a soft tissue imbalance and degeneration.

• Weight-bearing X-rays of the foot and ankle are required
• At times CT or MRI scans are required

• Pain medications e.g. NSAIDS such as Mobic or Panadol Osteo
• Footwear modification
  • lateral heel wedge
  • flared sole
• Activity modification
  • improve fitness and strength via non axial loading exercises e.g. cycling, swimming.
• Physiotherapy
  • strengthening of peroneal tendons
  • proprioception including wobble board and stretches
• External lace up ankle brace support or taping
• Protected weight-bearing may be required

Flatfoot due to failure of the tibialis-posterior tendon cannot be reversed with surgery, but many patients can manage their symptoms with non-operative measures. These measures do not modify the course of the disease.

Surgical options for flatfoot include:

• Bone realignment osteotomy
  cutting the heel bone and fixing with a screw
• Bone realignment osteotomy
  cutting the medial cuneiform bone and inserting a wedge.
• Fusion of the first TMTJ
  connecting the bones on either side of the tarsometatarsal joint may be required
• Debridement and repair of the tibialis posterior tendon
  with its adjacent tendon (Flexor Digitorum Longus) or performing a transfer
• Spring ligament repair or reconstruction

After surgery, patients should be:

• Non weight-bearing in a plaster cast for 2 weeks
• Partial weight-bearing or non-weight-bearing in a CAM boot between 2 to 6 - weeks (depends on nature of surgery) Commence physiotherapy at 6 weeks
• Returning to most activities around 6 months
• A full recovery may take up to 12 months

All surgery has risks involved, however every effort is made to reduce these risks. Risks include but are not limited to:

• Infection: superficial wounds or deep infections
• Clots: DVT (deep venous thrombosis) or PE (pulmonary embolus)
• Nerve damage: tingling, numbness or burning
• Ongoing pain
• Stiffness
• Non union: in a fusion, the bones may not heal together adequately
• General or anaesthetic risks including to the heart and lung
• Drug reactions/allergy
• Hardware complications
• Revision surgery

There are increased risks of surgery in diabetics, smokers, significant peripheral vascular disease, severe neuropathy, previous or current infection which may preclude a patient from surgery.

View FootForward for Diabetes (run by Diabetes Australia) for more information on foot care.