Posterior Tibial Tendon Reconstruction (Flatfoot Correction)

Why this approach — at MOS

Pre-operative planning for flatfoot reconstruction is detailed work. I obtain weight-bearing AP and lateral foot X-rays, a hindfoot alignment X-ray, and MRI. I measure the talo-first metatarsal angle (Meary's angle), calcaneal pitch, and hindfoot valgus angle to determine which components of the reconstruction are needed and in what magnitude of correction.

My standard Stage II reconstruction combines FDL transfer with medializing calcaneal osteotomy. I add lateral column lengthening when forefoot abduction is significant on weight-bearing X-ray — the threshold I use is an abduction angle that leaves significant "too many toes" sign that the MCO alone will not correct. I repair the spring ligament when it is visibly stretched or torn, because spring ligament competence is critical to maintaining the corrected talar head position after surgery.

For patients presenting from Bethesda and surrounding communities with Stage II PTTD who have had prior orthotics and PT without adequate relief, reconstruction is highly effective. Published outcomes show excellent correction of deformity and high patient satisfaction at 5–10 years. The recovery is long, but the functional improvement — including return of single-leg heel rise — justifies the investment.

I am direct with patients about what this reconstruction requires: two to three incisions, a long non-weight-bearing period for the calcaneal osteotomy to heal, and a dedicated physical therapy commitment. Patients who understand what they are getting into before surgery recover better than those who are surprised by the recovery demands.

Who is a candidate?

Indications

• Stage II adult acquired flatfoot: flexible hindfoot valgus, partial arch collapse, failure of non-operative management
• Persistent medial ankle pain and arch pain despite 3–6 months of orthotics and physical therapy
• Inability to perform a single-leg heel rise on the affected side
• Progressive deformity documented on serial weight-bearing X-rays (increasing talo-first metatarsal angle, increasing calcaneal pitch loss)
• MRI confirming posterior tibial tendon degeneration, elongation, or partial tear

Contraindications

• Stage I PTTD — tenosynovitis without significant deformity responds well to non-operative care; surgery is premature
• Stage III rigid deformity in patients who prefer conservative management — surgical risk/benefit must be carefully discussed
• Peripheral vascular disease insufficient for healing of medial and lateral incisions
• Poorly controlled diabetes or immunosuppression compromising healing

Conservative Treatment First

Stage I and early Stage II PTTD are managed non-operatively. The foundation is a rigid or semi-rigid custom orthotic with a medial arch support and hindfoot posting to correct heel valgus. This orthotic must be worn in all footwear — patients who use orthotics only some of the time have worse outcomes. A University of California Biomechanics Laboratory (UCBL) custom insert or an ankle-foot orthosis (AFO) provides more robust support for more advanced non-operative cases.

Physical therapy targeting posterior tibial muscle strengthening, calf stretching (Achilles contracture commonly develops in flatfoot and worsens arch mechanics), and intrinsic foot muscle strengthening is essential. A short course of anti-inflammatory medication helps during acute flares.

Surgery is recommended when a genuine trial of orthotics and physical therapy over 3–6 months has failed to control symptoms and functional impairment continues or the deformity is progressing.

The procedure

What Is Posterior Tibial Tendon Reconstruction (Flatfoot Correction)?

Posterior tibial tendon reconstruction corrects adult acquired flatfoot caused by a failing posterior tibial tendon. Surgery combines a tendon transfer (flexor digitorum longus) to replace the weakened tendon with bone realignment procedures — typically a calcaneal osteotomy and sometimes lateral column lengthening — to restore the foot's arch and correct malalignment.

Adult acquired flatfoot deformity (also called posterior tibial tendon dysfunction, or PTTD) is a progressive condition in which the posterior tibial tendon — the primary dynamic support of the medial arch — weakens and fails over time. As the tendon fails, the medial arch collapses, the heel tilts outward (hindfoot valgus), and the forefoot abducts (points outward). Patients develop pain along the inner ankle and arch, swelling, and inability to perform a single-leg heel rise on the affected foot.

PTTD is staged by severity, and treatment is matched to stage:

Stage I: The tendon is painful and inflamed (tenosynovitis) but has not yet lengthened significantly. The arch is maintained. Treatment: non-operative with orthotics and physical therapy. Surgery rarely needed.

Stage II: The tendon has elongated, the hindfoot has become valgus, and the arch has partially collapsed — but the deformity is still flexible (the heel corrects when standing on tiptoe). This is the primary surgical candidate stage. Reconstruction aims to restore alignment in a flexible foot.

Stage III: The deformity is rigid — the heel no longer corrects on tiptoe, and fixed arthritic changes are present. Reconstruction alone is insufficient; subtalar or hindfoot fusion may be necessary.

Stage IV: The deformity has propagated to the ankle joint, causing valgus tilt of the talus in the mortise. Ankle involvement requires more complex treatment.

This page focuses primarily on Stage II surgical correction — the most common reconstructive scenario.

What Happens During Posterior Tibial Tendon Reconstruction?

Surgery is performed at an ambulatory surgery center under regional or general anesthesia. The reconstructive plan is determined pre-operatively based on deformity stage and imaging, and may include the following components:

Anesthesia and positioning: The patient is positioned supine with the operative leg elevated slightly. Pneumatic tourniquets may be applied. A popliteal nerve block is typically used.

Component 1 — FDL Tendon Transfer to Navicular: A medial incision behind and below the medial malleolus exposes the posterior tibial tendon (degenerated, elongated, or torn) and the flexor digitorum longus tendon (lying just posterior to it). The degenerated PTT is excised. The FDL is harvested from its course behind the medial malleolus and transferred to the navicular bone — the primary attachment of the posterior tibial tendon. A bone tunnel is created in the navicular and the FDL is secured with an interference screw. This replaces the dynamic arch support function of the failed PTT.

Component 2 — Medializing Calcaneal Osteotomy (MCO): A lateral incision over the calcaneus is made. A diagonal osteotomy cut is made through the posterior calcaneus. The posterior heel fragment is shifted medially by approximately 8–10 mm, correcting the hindfoot valgus. The osteotomy is fixed with one or two large screws. This is the most critical static correction — realigning the heel under the leg restores the mechanical axis.

Component 3 — Lateral Column Lengthening (LCL), when needed: For feet with significant forefoot abduction (the forefoot pointing outward), a bone graft is inserted into the calcaneus at the calcaneocuboid joint, lengthening the lateral column and correcting forefoot abduction. LCL is added to MCO when abduction is significant.

Component 4 — Spring Ligament Repair: The spring (plantar calcaneonavicular) ligament, which supports the talar head, is often stretched in PTTD. Direct repair or imbrication of this ligament reinforces the medial column.

Component 5 — Subtalar Fusion (Stage III): For rigid flatfoot deformity, the subtalar joint (between talus and calcaneus) is fused rather than osteotomized. This permanently corrects hindfoot position but eliminates subtalar motion.

Closure: Multiple incisions are closed in layers. A well-padded posterior splint holds the foot in corrected position.

Recovery timeline

Frequently Asked Questions