The posterior tibialis muscle begins deep in your calf. The muscle is connected to the arch of your foot by a tendon that runs along the inside of your ankle, just behind the large bump called the medial malleolus. When you walk, the posterior tibialis muscle lifts the arch of your foot.
Posterior tibial tendon dysfunction is one of the most common foot and ankle problems. The tendon may be damaged from an acute injury, like an accident or fall. More commonly, problems arise from overuse or repeated strain. Ongoing irritation slowly damages the tendon’s fibers and eventually leads to weakening and degeneration. This decreases the tendon’s ability to support your foot when you walk. As the tendon becomes less effective, the arch of your foot is allowed to collapse, which further increases the strain on the muscle and tendon.

The condition is often triggered from overuse and/or training on excessively hard surfaces. Other factors that can contribute to posterior tibial tendon dysfunction include: obesity, diabetes, hypertension, prior surgery or steroid injections.

Symptoms include pain or swelling along the course of the tendon, particularly behind your inner ankle bone. Symptoms often begin following an increase in training intensity or duration. Standing, walking, or running will likely increase your discomfort. Your pain may be aggravated by spending prolonged periods of time on your feet, especially, when standing tiptoe and walking stairs or uneven surfaces.

Early diagnosis and treatment is important to slow progression of the disorder. You may need to temporarily limit weight-bearing activity to allow your tendon to heal. Using a stationary cycle, elliptical machine, or swimming can be good alternatives to walking and running. Your doctor will likely prescribe arch supports or orthotics to help support your foot. You will be given exercises to strengthen the posterior tibialis muscle. These exercises should be performed while wearing shoes with good arch supports. In certain instances, a walking cast or boot may be needed to temporarily protect your foot.