An incision is made along the inner ankle and foot. The diseased tibialis posterior tendon is assessed — if irreparably damaged, it is debrided or excised. The flexor digitorum longus (FDL) tendon is transferred to replace the function of the tibialis posterior, providing dynamic arch support. This tendon transfer is usually combined with a calcaneal osteotomy and possibly spring ligament repair or lateral column lengthening. The operation takes two to three hours as a combined procedure.
Surgery is recommended for stage II adult acquired flatfoot deformity (flexible but progressive) with a ruptured or degenerate tibialis posterior tendon causing arch collapse, heel valgus, and pain that has not responded to orthotics and physiotherapy.
Custom orthotics with medial arch support, ankle-foot orthosis, tibialis posterior strengthening exercises, supportive footwear, and activity modification. These are effective for many patients, particularly in early-stage disease.
Weight-bearing X-rays, MRI to assess tendon quality, and clinical assessment of deformity flexibility. Smoking cessation essential.
Restoration of arch support, correction of heel alignment, reduced pain, and improved walking. Most patients achieve good pain relief and functional improvement.
Prolonged recoveryExpected
Non-weight-bearing for six to eight weeks. Full recovery nine to twelve months.
SwellingExpected
Prolonged foot and ankle swelling.
ScarExpected
Multiple incisions on the inner foot and ankle.
Donor tendon weaknessCommon
Loss of FDL function may slightly weaken lesser toe flexion. Rarely noticeable.
Non-unionUncommon
If osteotomy or fusion is included. Higher in smokers.
Nerve injuryUncommon
Tibial nerve or medial plantar nerve.
Wound healingUncommon
Multiple incisions increase risk.
RecurrenceUncommon
Flatfoot may recur, particularly if orthotics are not used.
General or spinal anaesthesia with ankle block.
Non-weight-bearing cast for six to eight weeks. Boot for four to six weeks. Physiotherapy from eight weeks. Custom orthotics long-term. Full recovery nine to twelve months.
X-rays at six weeks, three months, and six months.
Why transfer a different tendon?
The tibialis posterior tendon is often too damaged to repair directly. The FDL tendon is the most similar available tendon in terms of direction of pull and provides effective dynamic arch support.
Will I need orthotics forever?
Most patients benefit from long-term use of supportive orthotics, even after successful surgery, to maintain the correction.