The Achilles tendon is a strong, normally very stable tendon, which attaches the lower leg muscles to the foot in the rear lower leg area. It starts at the heel bone and pulls further under the foot in a wide tendon plate. The radiating musculature is the strong rear lower leg muscle, M. Triceps surae, which gives the calf its shape.
It includes the gastrocnemius muscle, which originates from the lower thigh bone and thus passes over two joints, the knee and the ankle, and the soleus muscle, which comes from the upper lower leg bone and thus has only one function in the ankle joint. Together they bend the foot downwards (plantar flexion), thus enabling walking and jumping movements against gravity. If injuries or overloading occur in the area described, the tendon can tear.
This results in an Achilles tendon rupture. The cause of an Achilles tendon rupture is usually a recurring (chronic) overloading. This may be due to sports or unphysiological movement patterns, but small injuries to the tendon occur repeatedly.
The body can only repair and compensate for this for a while until the rupture occurs. Usually a direct event such as sprinting off or jumping off the triggers, combined with the previous small injuries caused by long periods of overload. Faulty or overloaded triggers are the most common cause.
The first symptom of an Achilles tendon rupture is a loud bang. Since the tendon is exposed to great tension in order to transmit a lot of force, the rupture is usually clearly audible. This is followed by the classic signs of inflammation: Hemorrhage, swelling, overheating, functional impairment or loss of function in the rupture and severe pain.
Normal walking is no longer possible. In the later course, loss of strength and movement becomes noticeable. The simplest test to detect a rupture of the Achilles tendon is the so-called Thompson test: lie on the treatment bench/table/bed in a prone position.
The tester now compresses the calf muscles with his hand. If the foot is moved by this, the tendon is still intact. If the tendon were torn, i.e. continuity were interrupted, the foot would not move when the muscles are compressed.
Imaging procedures are also used to ensure the diagnosis of Achilles tendon rupture. X-rays, ultrasound or MRT are suitable for this purpose. After the swelling subsides, a dent can be seen or felt in the area of the tear, especially when lifting the foot.
To treat an Achilles tendon rupture, there is the option of conservative therapy (i.e. without surgery) or surgery with reattachment/sewing of the tendon. In both cases, the foot is partially resilient again after a few weeks, ready for work after about two months and ready for sports after about half a year. With a minimally invasive procedure, the foot can be fully functional again earlier.
