Achilles tendinopathy is an irritation of the Achilles tendon, a thick band of tissue along the back of the lower leg that connects the calf muscles to the heel. The term tendinopathy refers to any problem with a tendon, either short or long term. The Achilles tendon helps to balance forces in the leg and assists with movement of the leg and the ankle joint. Achilles tendinopathy results when the demand placed on the Achilles tendon is greater than its ability to function. This can occur after 1 episode (acute injury) or after repetitive irritation or “microtrauma” (chronic injury).
The severity of acute injuries is graded based on the amount of damage to the tendon:
- Grade I: Mild strain, disruption of a few fibers. Mild to moderate pain, tenderness, swelling, stiffness. Expected to heal normally with conservative management.
- Grade II: Moderate strain, disruption of several fibers. Moderate pain, swelling, difficulty walking normally. Expected to heal normally with conservative management.
- Grade III: Complete rupture, often characterized by a “pop,” immediate pain, inability to bear weight. Typically requires surgery to repair.
Most often, Achilles tendon pain is the result of repetitive trauma to the tendon. This repetitive strain can result in chronic Achilles tendinopathy, which is a gradual breakdown of the tissue and is most often treated with physical therapy.
Achilles tendinopathy may result from a combination of several different variables, including:
- Ankle stiffness
- Calf tightness
- Calf weakness
- Abnormal foot structure
- Abnormal foot mechanics
- Improper footwear
- A change in an exercise routine or sport activity
Pain can be present at any point along the tendon; the most common area to feel tenderness is just above the heel, although it may also be present where the tendon meets the heel.