Torn Achilles tendon, magnetic resonance imaging (MRI) scan. Rupturing the Achilles tendon (elongated dark tissue surrounded by white, upper right) is the most common tendon break injury and often results from overexertion in sports. The Achilles tendon, also known as the calcaneal tendon or the tendocalcaneous, is the thickest and strongest tendon in the body. It connects the calf muscles to the heel bone (calcaneus). Achilles ruptures are most common in males aged 30-40 years. Treatment can either be by non-surgical means, such as using a plaster cast to immobilise the foot, or by stitching the ends of the tear back together.