There are multiple factors contributing to the development of this problem. Injury to the nerves of the foot, laxity (looseness), or dysfunction of the spring ligament and tendon structures on the inside part of the foot, such as the posterior tibialis tendon, can all result in deformity of the foot and/or ankle resulting in AAFD. Subluxation (partial dislocation) of the subtalar or talonavicular joints can occur. A bone fracture is also a possible cause. The resulting joint deformity from any of these problems can lead to AAFD.

Dysfunction of the posterior tibial tendon has always been linked with AAFD. The loss of active and passive pull of the tendon alters the normal biomechanics of the foot and ankle.

The reasons for this can be many and varied as well. Diabetes, high blood pressure, and prolonged use of steroids are some of the more common causes of AAFD brought on by impairment of the posterior tibialis tendon. Overstretching or rupture of the tendon from a traumatic activity can also result in tendon and muscle imbalance in the foot leading to AAFD. Loss of blood supply for any reason in the area of the posterior tibialis tendon is another factor.

Rheumatoid Arthritis also one of the more common causes of AAFD. About half of all adults with this type of arthritis will develop AAFD over time. In such cases, the condition is gradual and progressive due to the laxity in the ligaments that accompanies this type of arthritis.

Obesity has also been linked with this condition. The excess weight causes pressure on the foot, which causes the arch to drop. Misalignment of the lower extremities in obese patients also contributes to the deformity. It should be noted that poor alignment of the lower extremities, in anyone, obese or not, can also progressively lead to AAFD.

Conservative (non-operative) care is advised as the first line of treatment. A simple modification to your shoe may be all that’s needed in the early stages of this injury. Sometimes purchasing shoes with a good arch support is sufficient. For other patients, an off-the-shelf (prefabricated) shoe insert or orthotic works well.

Physical Therapy at Physioflow is an important part of treating and resolving AFFD, particularly in the early stages of development, when the foot remains flexible. 

Treatment usually begins with strengthening exercises for your foot and posterior tibialis muscle. As mentioned above, these muscles work to lift the arch of the foot. Strengthening the muscles of the hip, which control alignment down the lower leg chain, also assist in lifting the arch of the foot. 

Specific lower leg stretches are important, particularly for the muscles of your calf, which, when tight, can force the foot out of alignment. When performing all stretches, it is imperative that you maintain good alignment of your foot and arch so as not to compound the forces going through your already flattened arch.

Being that AAFD develops over time, it is common for patients to not even notice how flat their feet are. The position of your feet becomes the ‘new normal.’ Re-learning the proper position of your arch is crucial to relieving the pain caused by AAFD as well as stopping the progression of any deformity. Proprioception is the term used to describe one’s sense of joint position.  Dr. Trinh will teach you what the correct position of your foot and arch should be and will give you exercises that challenge the proprioception of your knee, foot, ankle, and arch. 

If you are involved in a high-level sport, it is important to eventually add to perform squatting and jumping movements while maintaining proper foot and leg alignment, as well as arch control.