Achilles Tendon Rupture

Acute Achilles tendon rupture is a complete or partial tear of the conjoined gastrocnemius-soleus tendon, usually 2 to 6 cm above its calcaneal insertion.

UK studies report an annual incidence of roughly 8 to 22 per 100,000. The typical patient is a man aged 30 to 50 playing an occasional explosive sport such as badminton, squash or tennis.

Up to around 1 in 4 ruptures are missed at first presentation, classically labelled a calf sprain at 48 to 72 hours, once the pain has settled and haematoma has filled the gap.

The Achilles is the largest and strongest tendon in the body. It is formed by gastrocnemius and soleus and inserts on the posterior calcaneal tuberosity. It has no true synovial sheath; a vascular paratenon supplies most of its blood. A relatively hypovascular zone 2 to 6 cm above the insertion is the usual site of rupture.

The mechanism is sudden eccentric load on a dorsiflexed foot with the knee extended, classically push-off when accelerating or pivoting. Ruptured tendons almost always show pre-existing tendinopathic change (collagen disorganisation, increased ground substance, neovascularisation), even in people with no previous symptoms: an old tendon failing under sudden load.

Risk factors:

• •Previous Achilles tendinopathy
• •Fluoroquinolone use, such as ciprofloxacin or levofloxacin (MHRA warning)
• •Recent corticosteroid exposure
• •Increasing age, male sex and intermittent rather than regular training