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Achilles Tendinitis


Paul L. Liebert

, MD, Tomah Memorial Hospital, Tomah, WI

Last full review/revision Jan 2020| Content last modified Jan 2020

Achilles tendon injuries include inflammation of the paratenon and partial or complete tears.

Achilles tendinitis is very common among running athletes. The calf muscles attach to the calcaneus via the Achilles tendon. During running, the calf muscles help with the lift-off phase of gait. Repetitive forces from running combined with insufficient recovery time can initially cause inflammation in the tendon paratenon (fatty areolar tissue that surrounds the tendon). A complete tear of the Achilles tendon is a serious injury, usually resulting from sudden, forceful stress. Tendon tears can occur with minimal exertion in people who have taken fluoroquinolone antibiotics.

Symptoms and Signs

The primary symptom of Achilles tendon inflammation is pain in the back of the heel, which initially increases when exercise is begun and often lessens as exercise continues.

A complete tear of the Achilles tendon typically occurs with a sudden forceful change in direction when running or playing tennis and is often accompanied by a sensation of having been struck in the back of the ankle and calf with an object such as a baseball bat.


  • Clinical evaluation

On examination, an inflamed or partially torn Achilles tendon is tender when squeezed between the fingers. Complete tears are differentiated by

  • Sudden, severe pain and inability to walk on the extremity
  • A palpable defect along the course of the tendon
  • A positive Thompson test (while the patient lies prone on the examination table, the examiner squeezes the calf muscle; this maneuver by the examiner does not cause the normally expected plantar flexion of the foot)


  • Ice, nonsteroidal anti-inflammatory drugs (NSAIDs), and stretches
  • Modification of activities
  • Sometimes a heel lift

Tendon inflammation should initially be treated with ice, gentle calf muscle stretching, and use of NSAIDs.

A heel lift can be placed in the shoes to take tension off the tendon. Athletes should be instructed to avoid uphill and downhill running until the tendon is not painful and to engage in cross-training aerobic conditioning.

Most clinicians treat complete tears of the Achilles tendon with surgical repair. However, some recent studies (1-2) have shown that nonoperative management (including highly structured rehabilitation activities) gives similar long-term results in regards to strength, range of motion, and ability to do pre-injury activity. Data are still being evaluated, but a reasonable approach is to do surgical repair for athletes and highly active people and consider nonoperative management as an effective alternative for older and/or less active patients

Exercises to Stretch the Achilles Tendon

Treatment references

  • Lantto L, Heikkinen J, Flinkkila T, et al: A prospective randomized trial comparing surgical and nonsurgical treatments of acute Achilles tendon ruptures. Am J Sports Med Am J Sports Med 44(9):2406-2414, 2016. doi: 10.1177/0363546516651060.
  • Parisien RL, Dodson CC, et al: Face off: Surgical versus nonsurgical treatment of acute Achilles tendon ruptures. AAOS Now July 2016, cover.

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