Flatfoot / Tibialis posterior dysfunction

Presentation

• Adult onset flat foot is usually related to degeneration of the tibialis posterior tendon.
• Patients have a fallen arch, pain along the inside of their foot and ultimately tilting of their heel outwards.
• This deterioration is oftern gradual, however occasionally can be after an acute tear of the tendon.
• The altered mechanics of the foot ultimately result in arthritis of surrounding joints.

Investigation

Your GP should initially request these investigations:

• Weight bearing foot X-ray (AP, oblique and lateral)

Your surgeon may also request the following investigations for more information or surgical planning:

• MRI to look at tendon and joints

Conservative Treatment

Initial treatment of Flatfoot / Tibialis posterior dysfunction could include:

• Orthotics - arch support, UCBL or Arizona
• Physiotherapy - for strengthening and calf stretching
• Injection of local anaesthetic and steroid into tendon sheath

Surgical Treatment

Surgical treatment of Flatfoot / Tibialis posterior dysfunction includes:

Calcaneal osteotomy, tibialis posterior debridement and FDL transfer

• Incision on outside of heel
• Saw used to cut through calcaneus and shift it sideways. Fixed with 2 screws.
• Incision along inside of foot
• Tibialis posterior tendon identified and debrided as necessary
• FHL tendon cut distally and transferred into navicular bone to reinforce tibialis posterior tendon
• Occasionally - sinus tarsi screw inserted or internal brace used to reinforce correction

Condition specific risks include:

1. Non-union of osteotomy
2. Recurrent deformity
3. Arthritis

General risks of surgery include:

1. Infection
2. Damage to nerves/blood vessels
3. DVT / PE (blood clots)
4. Anaesthetic risks

Recovery

Recovery from Flatfoot / Tibialis posterior dysfunction surgery will include:

• Keep foot elevated as much as possible, especially for initial 72 hours
• Keep dressings dry and intact until post operative appointment.
• Pain killers may be required for up to 2 weeks.
• Removal of stitches: 10-14 days at first post operative appointment.
• Touch weight bear in backslab for 2 weeks
• Weight-bearing as tolerated in moonboot for 4 weeks
• Recommencement of most activities: 12 weeks. Full recovery: 6-12 months.

Every patient’s recovery is individual and depends on the severity of the injury and the complexity of the surgery.