Originally known as posterior tibial tendon dysfunction or insufficiency, adult-acquired flatfoot deformity encompasses a wide range of deformities. These deformities vary in location, severity, and rate of progression. Establishing a diagnosis as early as possible is one of the most important factors in treatment. Prompt early, aggressive nonsurgical management is important. A patient in whom such treatment fails should strongly consider surgical correction to avoid worsening of the deformity. In all four stages of deformity, the goal of surgery is to achieve proper alignment and maintain as much flexibility as possible in the foot and ankle complex. However, controversy remains as to how to manage flexible deformities, especially those that are severe.
Posterior tibial tendon dysfunction is the most common cause of acquired adult flatfoot. Sometimes this can be a result of specific trauma, but usually the tendon becomes injured from wear and tear over time. This is more prevalent in individuals with an inherited flat foot but excessive weight, age, and level of activity are also contributing factors.
Posterior tibial tendon insufficiency is divided into stages by most foot and ankle specialists. In stage I, there is pain along the posterior tibial tendon without deformity or collapse of the arch. The patient has the somewhat flat or normal-appearing foot they have always had. In stage II, deformity from the condition has started to occur, resulting in some collapse of the arch, which may or may not be noticeable. The patient may feel it as a weakness in the arch. Many patients initially present in stage II, as the ligament failure can occur at the same time as the tendon failure and therefore deformity can already be occurring as the tendon is becoming symptomatic. In stage III, the deformity has progressed to the extent where the foot becomes fixed (rigid) in its deformed position. Finally, in stage IV, deformity occurs at the ankle in addition to the deformity in the foot.
First, both feet should be examined with the patient standing and the entire lower extremity visible. The foot should be inspected from above as well as from behind the patient, as valgus angulation of the hindfoot is best appreciated when the foot is viewed from behind. Johnson described the so-called more-toes sign: with more advanced deformity and abduction of the forefoot, more of the lateral toes become visible when the foot is viewed from behind. The single-limb heel-rise test is an excellent determinant of the function of the posterior tibial tendon. The patient is asked to attempt to rise onto the ball of one foot while the other foot is suspended off the floor. Under normal circumstances, the posterior tibial muscle, which inverts and stabilizes the hindfoot, is activated as the patient begins to rise onto the forefoot. The gastrocnemius-soleus muscle group then elevates the calcaneus, and the heel-rise is accomplished. With dysfunction of the posterior tibial tendon, however, inversion of the heel is weak, and either the heel remains in valgus or the patient is unable to rise onto the forefoot. If the patient can do a single-limb heel-rise, the limb may be stressed further by asking the patient to perform this maneuver repetitively.
Non surgical Treatment
Get treated early. There is no recommended home treatment. While in stage one of the deformity, rest, a cast, and anti-inflammatory therapy can help you find relief. This treatment is followed by creating custom-molded foot orthoses and orthopedic footwear. These customized items are critical in maintaining the stability of the foot and ankle. Once the tendon has stretched and deformity is visible, the chances of success for non-surgical treatment are significantly lower. In a small percentage of patients, total immobilization may arrest the progression of the deformity. A long-term brace known as an ankle foot orthosis is required to keep the deformity from progressing. The Richie Brace, a type of ankle foot orthosis, shows significant success as a treatment for stage two posterior tibial dysfunction. It is a sport-style brace connected to a custom corrected foot orthodic that fits into most lace-up footwear (including athletic shoes). It is also light weight and more cosmetically appealing than traditionally prescribed ankle foot orthosis. The Arizona Brace, California Brace or Gauntlet Brace may also be recommended depending on your needs.
Surgery should only be done if the pain does not get better after a few months of conservative treatment. The type of surgery depends on the stage of the PTTD disease. It it also dictated by where tendonitis is located and how much the tendon is damaged. Surgical reconstruction can be extremely complex. Some of the common surgeries include. Tenosynovectomy, removing the inflamed tendon sheath around the PTT. Tendon Transfer, to augment the function of the diseased posterior tibial tendon with a neighbouring tendon. Calcaneo-osteotomy, sometimes the heel bone needs to be corrected to get a better heel bone alignment. Fusion of the Joints, if osteoarthritis of the foot has set in, fusion of the joints may be necessary.