Keys To Conservative Care For Adult-Acquired Flatfoot
Given the common nature of adult-acquired flatfoot, these authors offer a closer look at the use of popular orthoses and braces in managing the various stages of flatfoot secondary to posterior tibial tendon dysfunction.
A wide assortment of conservative treatment options exists for the treatment of adult-acquired flatfoot (AAF). Unfortunately, there is little research to support the use of one device over another. For many podiatrists, surgical treatment has become the mainstay of treatment for advanced posterior tibial tendon dysfunction (PTTD).
Even so, conservative treatment still has its place and is indicated for those patients who refuse surgery (possibly due to socioeconomic issues) or those who are not good surgical candidates due to medical comorbidities. Accordingly, let us take a closer look at a few of the more popular and well-known modalities including the University of California Biomechanics Laboratory (UCBL) orthotic, custom ankle foot orthoses (AFOs) such as the Richie Brace and Arizona Brace, and the patellar tendon bearing (PTB) brace.
Choosing the appropriate device is dependent on one’s understanding of AAF and the most common underlying causal process PTTD.
Posterior tibial tendon dysfunction plays a crucial role in the development of pathologic flatfoot deformity in most cases. When the posterior tibial tendon is unable to lock the midtarsal joint in midstance, the stability of the midtarsal joint remains compromised during heel off. This places excessive pressures on the plantar ligamentous, muscular and tendinous structures. This leads to attenuation of these structures and collapse of the medial longitudinal arch.
There are many underlying causes of PTTD. These may include diabetes, trauma to the tendon, diminished tendon vascularity, systemic arthritidies or simply age-related degeneration of collagen fibers.1,2
Complete and accurate evaluation of the entire patient is necessary prior to choosing the treatment plan. When it comes to the treatment plan for a patient with AAF secondary to PTTD, one must consider the stage of the deformity, specifically the flexibility of the deformity and the presence of any associated degenerative changes. Physicians also need to take into account the underlying cause of the deformity and the patient’s medical comorbidities.
Although many have attempted to create new classifications for PTTD, the best known and most commonly used is the system developed by Johnson and Strom in 1989 and subsequently modified by Myerson in 1996.3,4 Accordingly, the following suggested treatment options are based on the progression of deformity within this staging system.
A Guide To Treatment For Stage I PTTD
In the first stage, acute tendonitis/tenosynovitis is associated clinically with swelling and pain upon palpation of the posterior tibial tendon, both along the distal course of the tendon and at its insertion onto the navicular tuberosity. The onset may be acute or insidious, and the patient may complain of fatigue with activity.
Research has shown that the use of orthotics in these patients can help in the selective activation of the posterior tibial tendon. Accordingly, the orthotics reduce stress on other tendons of the foot, which are frequently recruited in compensation and over-activated in cases of PTTD, leading to symptoms of fatigue.5
Often when one evaluates a patient with early stage PTTD, the patient will be able to perform a single limb heel rise and no observable deformity of the foot will be appreciable.
The ultimate goals of treatment in this stage are early recognition and protection to prevent tendon degeneration and subsequent deformity. In addition, early treatment can allow resolution of symptoms and a return to a high level of activity.