Over 60 Million Americans suffer from Adult Acquired Flatfoot
(AAF), otherwise known as Posterior Tibial Tendon Dysfunction or PTTD.
This condition generally occurs in adults from 40-65 years of age, and it usually only occurs in one foot, not both. The Posterior Tibial (PT) Tendon courses along the inside part of the ankle and
underneath the arch of the foot. It is the major supporting structure for the arch. Over time, the tendon becomes diseased, from overuse, and starts to lose it's strength. As a result, the arch
begins to collapse, placing further strain on the PT Tendon, leading to further decrease in tendon strength, which causes further collapse of the arch. This is described as a progressive deformity
because it will generally get worse over time.
Women are affected by Adult Acquired Flatfoot four times more frequently than men. Adult Flatfoot generally occurs in middle to older age people. Most people who acquire the condition already have
flat feet. One arch begins to flatten more, then pain and swelling develop on the inside of the ankle. This condition generally affects only one foot. It is unclear why women are affected more often
than men. But factors that may increase your risk of Adult Flatfoot include diabetes, hypertension, and obesity.
Many patients with this condition have no pain or symptoms. When problems do arise, the good news is that acquired flatfoot treatment is often very effective. Initially, it will be important to rest
and avoid activities that worsen the pain.
Starting from the knee down, check for any bowing of the tibia. A tibial varum will cause increased medial stress on the foot and ankle. This is essential to consider in surgical planning. Check the
gastrocnemius muscle and Achilles complex via a straight and bent knee check for equinus. If the range of motion improves to at least neutral with bent knee testing of the Achilles complex, one may
consider a gastrocnemius recession. If the Achilles complex is still tight with bent knee testing, an Achilles lengthening may be necessary. Check the posterior tibial muscle along its entire course.
Palpate the muscle and observe the tendon for strength with a plantarflexion and inversion stress test. Check the flexor muscles for strength in order to see if an adequate transfer tendon is
available. Check the anterior tibial tendon for size and strength.
Non surgical Treatment
In the early stages, simple pre-fabricated orthotics can help improve the heel position to reduce the mechanical load which is contributing to the symptoms. In advanced stages or long term orthotic
use, a plaster of paris or foam box cast can be taken and specific bespoke orthotics manufactured. If the condition develops further a AFO (ankle foot orthotic) may be necessary for greater control.
In more advanced stages of symptomatic Adult Acquired flat feet, where the conservative methods of treatment have failed there are various forms of surgery available depending upon the root cause of
the issue and severity.
In cases where cast immobilization, orthoses and shoe therapy have failed, surgery is the next alternative. The goal of surgery and non-surgical treatment is to eliminate pain, stop progression of
the deformity and improve mobility of the patient. Opinions vary as to the best surgical treatment for adult acquired flatfoot. Procedures commonly used to correct the condition include tendon
debridement, tendon transfers, osteotomies (cutting and repositioning of bone) and joint fusions. (See surgical correction of adult acquired flatfoot). Patients with adult acquired flatfoot are
advised to discuss thoroughly the benefits vs. risks of all surgical options. Most procedures have long-term recovery mandating that the correct procedure be utilized to give the best long-term
benefit. Most flatfoot surgical procedures require six to twelve weeks of cast immobilization. Joint fusion procedures require eight weeks of non-weightbearing on the operated foot - meaning you will
be on crutches for two months. The bottom line is, Make sure all of your non-surgical options have been covered before considering surgery. Your primary goals with any treatment are to eliminate pain
and improve mobility. In many cases, with the properly designed foot orthosis or ankle brace, these goals can be achieved without surgical intervention.