Achilles tendon tears are common. They typically occur during running or jumping and are most common among middle-aged men and athletes. Very rarely, spontaneous Achilles tendon tears have occurred in people who take fluoroquinolone antibiotics.
Achilles tendon tears may be partial or complete.
Diagnosis of Achilles tendon tears is clinical (1). The patient's ability to flex the ankle does not rule out a tear.
If clinicians suspect an Achilles tendon tear, 3 main tests can be done to help confirm the diagnosis.
For the Thompson test (calf squeeze test), the patient is prone, and the calf is squeezed to elicit plantar flexion. Results include the following:
The Matles test is used to assess resting tension. The patient is prone with the knee bent at 90° to shorten the gastrocnemius. The patient's feet are compared. Results include the following:
The Matles test is 88% sensitive and 85% specific for tears.
For palpation of the tendon gap, the patient is asked to stand on the affected leg (if possible). Then the clinician gently palpates the course of Achilles tendon and feels for a gap; a gap indicates that the tendon is torn.
Physical examination is more sensitive than MRI for detecting a Achilles tendon tear (2). A study of patients with an Achilles tendon tear (2012) found that if all 3 tests (Thompson, Matles, palpation of the gap) are positive, sensitivity for an Achilles tear is 100%. According to the American Academy of Orthopedic Surgeons guidelines (2009), diagnosis of a tear requires only one of the following (3):
1. Maffulli N: The clinical diagnosis of subcutaneous tear of the Achilles tendon: A prospective study in 174 patients. Am J Sports Med 26 (2):266–270, 1998.
2. Garras DN, Raikin SM, Bhat SB, et al: MRI is unnecessary for diagnosing acute Achilles tendon ruptures: Clinical diagnostic criteria. Clin Orthop Relat Res 470 (8):2268–2273, 2012. doi: 10.1007/s11999-012-2355-y.
3. American Academy of Orthopaedic Surgeons: The diagnosis and treatment of acute Achilles tendon rupture: Guideline and evidence report. American Academy of Orthopaedic Surgeons, 2009. Accessed 8/16/19.
Initial treatment of Achilles tendon tears consists of splinting with the ankle in plantar flexion and immediate referral to an orthopedic surgeon.
Whether tendon tears should be treated surgically is controversial.
Treatment may involve a posterior ankle splint with the ankle in plantar flexion for 4 weeks and avoidance of weight bearing.