A flat foot (pes planus) is a condition where the arch collapses, causing the entire sole to touch the floor when standing. While many people experience no problems, the condition can cause significant pain, fatigue, and difficulty walking, especially if the arch becomes rigid or progressively collapses. Surgery is generally considered only after conservative measures, such as custom orthotics, bracing, and physical therapy, have failed to relieve symptoms. The specific surgical approach is a collection of operations tailored to the patient’s age, foot flexibility, and deformity severity.
Procedures Focused on Soft Tissue Repair
Surgical correction often begins with addressing soft tissues, especially in flexible flatfoot or Posterior Tibial Tendon Dysfunction (PTTD). The posterior tibial tendon (PTT) is a primary arch stabilizer, and its damage is a common cause of acquired flatfoot. For early-stage PTTD, a tenosynovectomy may be performed, which involves removing inflamed tissue surrounding the tendon.
When the PTT is significantly damaged, a tendon transfer procedure is necessary to restore arch function. This involves re-routing a nearby tendon, such as the flexor digitorum longus (FDL), to take over the supportive role of the damaged PTT. The transferred tendon is anchored into the navicular bone to create dynamic arch support. The spring ligament, often stretched or torn, may also be repaired or reinforced during the procedure.
Soft tissue procedures rarely stand alone because the underlying bony structure requires realignment. These repairs are typically combined with a procedure that cuts and repositions the heel bone. This combined approach addresses both dynamic tendon support and static bone structure, ensuring a more complete correction.
Procedures Focused on Bony Realignment
Flatfoot surgery commonly involves osteotomies, which cut and reshape bones to rebuild the arch structure. These bony realignment procedures correct the complex, three-dimensional deformity of an acquired flatfoot. Correcting the bone alignment shifts the weight-bearing axis of the foot, reducing strain on tendons and ligaments.
A medial displacement calcaneal osteotomy (MCO) is frequently performed, where the heel bone (calcaneus) is cut and shifted inward (medially). This inward shift realigns the rear-foot and changes the pull of the Achilles tendon to support the arch. The bone is then fixed in its new position using screws or a plate until it heals.
Another common procedure is the lateral column lengthening, or Evans osteotomy. This involves cutting the calcaneus and inserting a bone graft or wedge on the outer side of the foot to lengthen the lateral column. This corrects forefoot abduction and restores midfoot alignment.
For flexible flatfoot in younger patients, a subtalar arthroereisis may be used. This involves inserting a small implant into the sinus tarsi, the space between the heel and ankle bones. This implant blocks excessive inward rolling of the heel, supporting the arch without permanently fusing the joint.
Joint Fusion Techniques
Joint fusion, or arthrodesis, is a definitive approach reserved for feet with rigid deformities, severe arthritis, or failed previous realignment attempts. Fusion involves removing damaged cartilage and joining the bones together with screws or plates to heal into a single, solid unit. This procedure eliminates motion but provides maximum stability and pain relief.
The most extensive technique is the triple arthrodesis, which fuses three joints in the hindfoot: the subtalar, talonavicular, and calcaneocuboid joints. This procedure corrects significant deformity and is indicated for late-stage, non-flexible flatfoot, often with end-stage arthritis. Fusing these joints creates a stable, well-aligned foundation.
Surgeons may also opt for isolated fusions, such as subtalar or talonavicular fusion, to stabilize individual joints. Isolated fusions are preferred because they preserve motion in adjacent joints better than a triple arthrodesis. Fusion procedures are the final option when joints are significantly damaged and joint-sparing reconstruction is impossible.
Recovery Timeline and Expected Outcomes
Recovery after flat foot surgery is a lengthy process. The foot is typically immobilized in a cast or splint for the first two to six weeks to protect the surgical site. During this initial non-weight-bearing phase, the patient relies on crutches or a knee scooter for mobility.
The patient then transitions into a removable walking boot for an additional four to six weeks. Protected weight-bearing is introduced around six to eight weeks post-operation, depending on the procedure and bone healing. Physical therapy begins during this stage to restore strength, flexibility, and a normal walking pattern.
Complete recovery and return to full activity, including sports, can take six months to a full year. The long-term prognosis is positive, aiming for significant pain reduction and improved function through realignment and stabilization procedures.