Adult flatfoot (adult acquired flatfoot) or posterior tibial tendon dysfunction
(PTTD) is a common pathology presented to foot and ankle specialists. PTTD is characterized by a valgus (everted) hindfoot, flattening of the longitudinal arch of the foot (collapse) and abduction of
the forefoot. This is a progressive deformity that begins flexible and can become rigid over time. The posterior tibial tendon (PT) is one of the main supporting structures of the foot arch. Changes
within this tendon cause flattening of the foot. There are four stages of this deformity that begins flexible and progressives, with no treatment, to a rigid deformity and with time may involve the
ankle joint. Patients usually present with pain in the foot or ankle stating the ankle is rolling. Its also common for patients to state they have difficulty walking barefoot. Pain is exacerbated
after physical activities. Pain is usually isolated to the inside of the foot along the course of the PT tendon.
As discussed above, many health conditions can create a painful flatfoot. Damage to the posterior tibial tendon is the most common cause of AAFD. The posterior tibial tendon is one of the most
important tendons of the leg. It starts at a muscle in the calf, travels down the inside of the lower leg and attaches to the bones on the inside of the foot. The main function of this tendon is to
hold up the arch and support your foot when you walk. If the tendon becomes inflamed or torn, the arch will slowly collapse. Women and people over 40 are more likely to develop problems with the
posterior tibial tendon. Other risk factors include obesity, diabetes, and hypertension. Having flat feet since childhood increases the risk of developing a tear in the posterior tibial tendon. In
addition, people who are involved in high impact sports, such as basketball, tennis, or soccer, may have tears of the tendon from repetitive use. Inflammatory arthritis, such as rheumatoid arthritis,
can cause a painful flatfoot. This type of arthritis attacks not only the cartilage in the joints, but also the ligaments that support the foot. Inflammatory arthritis not only causes pain, but also
causes the foot to change shape and become flat. The arthritis can affect the back of the foot or the middle of foot, both of which can result in a fallen arch.
Pain and swelling behind the inside of your ankle and along your instep. You may be tender behind the inner ankle where the posterior tibial tendon courses and occasionally get burning, shooting,
tingling or stabbing pain as a result of inflammation of the nerve inside the tarsal tunnel. Difficulty walking, the inability to walk long distances and a generalised ache while walking even short
distances. This may probably become more pronounced at the end of each day. Change in foot shape, sometimes your tendon stretches out, this is due to weakening of the tendon and ligaments. When this
occurs, the arch in your foot flattens and a flatfoot deformity occurs, presenting a change in foot shape. Inability to tip-toe, a way of diagnosing Posterior Tibial Tendon Dysfunction is difficulty
or inability to ?heel rise? (stand on your toes on one foot). Your tibialis posterior tendon enables you to perform this manoeuvre effectively. You may also experience pain upon attempting to perform
a heel rise.
The adult acquired flatfoot, secondary to posterior tibial tendon dysfunction, is diagnosed in a number of ways with no single test proven to be totally reliable. The most accurate diagnosis is made
by a skilled clinician utilizing observation and hands on evaluation of the foot and ankle. Observation of the foot in a walking examination is most reliable. The affected foot appears more pronated
and deformed compared to the unaffected foot. Muscle testing will show a strength deficit. An easy test to perform in the office is the single foot raise. A patient is asked to step with full body
weight on the symptomatic foot, keeping the unaffected foot off the ground. The patient is then instructed to "raise up on the tip toes" of the affected foot. If the posterior tibial tendon has been
attenuated or ruptured, the patient will be unable to lift the heel off the floor and rise onto the toes. In less severe cases, the patient will be able to rise on the toes, but the heel will not be
noted to invert as it normally does when we rise onto the toes. X-rays can be helpful but are not diagnostic of the adult acquired flatfoot. Both feet - the symptomatic and asymptomatic - will
demonstrate a flatfoot deformity on x-ray. Careful observation may show a greater severity of deformity on the affected side.
Non surgical Treatment
Because of the progressive nature of PTTD, early treatment is advised. If treated early enough, your symptoms may resolve without the need for surgery and progression of your condition can be
arrested. In contrast, untreated PTTD could leave you with an extremely flat foot, painful arthritis in the foot and ankle, and increasing limitations on walking, running, or other activities. In
many cases of PTTD, treatment can begin with non-surgical approaches that may include. Orthotic devices or bracing. To give your arch the support it needs, your foot and ankle surgeon may provide you
with an ankle brace or a custom orthotic device that fits into the shoe. Immobilization. Sometimes a short-leg cast or boot is worn to immobilize the foot and allow the tendon to heal, or you may
need to completely avoid all weight-bearing for a while. Physical therapy. Ultrasound therapy and exercises may help rehabilitate the tendon and muscle following immobilization. Medications.
Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, help reduce the pain and inflammation. Shoe modifications. Your foot and ankle surgeon may advise changes to make with your shoes and
may provide special inserts designed to improve arch support.
The indications for surgery are persistent pain and/or significant deformity. Sometimes the foot just feels weak and the assessment of deformity is best done by a foot and ankle specialist. If
surgery is appropriate, a combination of soft tissue and bony procedures may be considered to correct alignment and support the medial arch, taking strain off failing ligaments. Depending upon the
tissues involved and extent of deformity, the foot and ankle specialist will determine the necessary combination of procedures. Surgical procedures may include a medial slide calcaneal osteotomy to
correct position of the heel, a lateral column lengthening to correct position in the midfoot and a medial cuneiform osteotomy or first metatarsal-tarsal fusion to correct elevation of the medial
forefoot. The posterior tibial tendon may be reconstructed with a tendon transfer. In severe cases (stage III), the reconstruction may include fusion of the hind foot,, resulting in stiffness of the
hind foot but the desired pain relief. In the most severe stage (stage IV), the deltoid ligament on the inside of the ankle fails, resulting in the deformity in the ankle. This deformity over time
can result in arthritis in the ankle.