A Guide To Conservative Care For Adult Flatfoot
Stage I. Peritendinitis and tenosynovitis of the posterior tibial tendon present. The rearfoot remains mobile and the patient has pain medially. A single heel rise test reveals mild weakness to the posterior tibial tendon.
Stage II. The posterior tibial tendon is elongated and attenuated. The rearfoot remains mobile. However, the calcaneus is in valgus on stance. There is still pain medially. The patient is still able to perform the single heel rise test although it is weak. A positive “too many toes” sign is present.
Stage III. Degeneration of the posterior tibial tendon is evident. The rearfoot becomes fixed and less flexible, and the calcaneus remains in valgus on stance. The patient may have pain both medially and laterally due to impingement laterally. A positive “too many toes” sign is visible.
Stage IV. A valgus tilt to the talus in the ankle mortise and early degeneration of the ankle joint are present.
Conti and colleagues developed another common classification system.11 This classification system is based on MRI and evaluates the state of the posterior tibial tendon.
Type I tear. One or two fine longitudinal splits occur in the tendon without degeneration of the tendon.
Type II tears. This involves wider, longitudinal tendon splits and intramural degeneration. The tendon also may show a variable diameter on selected cuts where a bulbous section may be distal to an attenuated portion.
Type III tears. More diffuse swelling and uniform degeneration of the tendon are present. A few tendon strands may remain or the tendon may be replaced entirely with scar tissue.
Current Concepts In Conservative Treatment
Goals for conservative treatment of flexible flatfoot include eliminating clinical symptoms, improvement of rearfoot alignment and prevention of progressive deformity.1
Treatment for flexible flatfoot generally begins with immobilization via a removable cast boot or below the knee cast for up to six to eight weeks. This decreases inflammation and prevents overuse for acute tenosynovitis. Steroid injection into the tendon sheath for tenosynovitis continues to be controversial due to the adverse effect of tendon rupture.1
One may also utilize UCBL orthotics to stabilize the rearfoot. These are helpful in patients with a stage II deformity because the rearfoot is flexible and passively correctable in this stage. These orthotics limit the range of motion of the subtalar joint and forefoot abduction. Other orthotics may have a medial posting, like the Blake inverted orthotic, to decrease the strain on the posterior tibial tendon medially and push the foot into a more rectus position.1
Changes in shoegear and shoegear modifications are often beneficial to patients with a flexible flatfoot deformity. An extra depth shoe is able to provide a long rigid medial counter, a soft leather upper, high toe boxes and soft soles to absorb some ground reactive forces during gait. One can add a medial stabilizer to the shoe as well as a rocker bottom to assist in toe off. It is also possible to add a medial wedge inside the shoe to support the posterior tibial tendon.12
The Baldwin Boot Brace (Bolt Systems) is able to provide edema control, stability of affected joints and soft tissue protection. This low-profile device controls and restricts subtalar joint motion. This boot is able to provide good control of tibial rotational forces and has anterior padding to protect the anterior lower leg. One can use the Baldwin Boot Brace for patients with stage III deformity and patients with a fixed deformity as it holds the deformity and protects soft tissues.12
A temporary bracing option for posterior tibial tendon tenosynovitis is a stirrup brace. This brace is not able to control motion in the sagittal plane but it is able to help unload the posterior tibial tendon by transferring plantarflexion to the Achilles tendon and relieves strain from plantarflexion from the posterior tibial tendon.13