Heel Tendonitis (Tenosynovitis): Causes, Symptoms, and Treatment Explained by a Foot and Ankle Specialist (DPM) As a foot and ankle specialist, heel pain is one of the most common complaints I see. While many patients assume it is plantar fasciitis, some cases are actually related to tendon inflammation around the heel, often referred to as tendonitis or tenosynovitis. What Is Heel Tendonitis? Heel tendonitis typically involves inflammation of the Achilles tendon or surrounding tendon sheath. This tendon connects the calf muscles to the heel bone and plays a critical role in walking and movement. When the tendon or its sheath becomes irritated, pain develops in the back or around the heel. Common Causes of Heel Tendonitis    Overuse and Repetitive Stress Activities such as walking, running, or standing for long periods can overload the tendon. Repeated stress is the most common cause. [...]