Achilles tendon tendinosis

Achilles tendon is the strongest and biggest tendon of the human locomotor apparatus. It is an integral part of the triceps surae muscle at the back of the lower leg which has three parts. The m. soleus part which is positioned lower and whose end is the Achilles tendon and the two gastrocnemius muscles positioned higher and partly above the soleus muscle. The Achilles tendon which connects to the lower back part of the calcaneus or heel bone is 5-6 cm long and 5-6 mm wide.

Achilles tendon tendinitis  used to refers to a inflammatory state inside the tendon which can be localized on three places, at the transition point where the muscle transforms into the tendon tissue (miotendinosis), inside the tendon tissue itself (tendinosis) and at the connecting point of the tendon on the heel bone (Haglund disease). The place where the pain and overuse most commonly occur is the tendon tissue itself. Earlier it was thought that the background for this pain syndrome was an inflammatory process in the tendon tissue, but newer researches have found that pain and tenderness of the tendon happen due to overload and strain put on it, therefore the name tendinosis has been implemented because tendinitis implies an inflammatory state.

The most common reasons for Achilles tendinosis and pain are certain patterns during walking or running or due to aquired or congenital feet/foot deformations which put added strain on the tendon during performance of activities such as running, walking, jumping, etc. Some factors can whuch can cause pain and put more strain on the Achilles tendon are anatomical misalignments of the foot/feet (flat foot/feet, valgus or varus position of the feet), abnormal foot pronation while running or walking, strenght and flexibility disbalance of the lower leg muscles, specifically between integral parts of the triceps surae muscle at the back of the lower leg because Achilles tendon is one of its parts. Aging process, being overweight, having decreased blood circulation in the tendon, especially in its middle third, use of low quality or overused footwear, often changes of the training surface, inproper training methods (sudden or too big changes in the intensity/extensity of training) can also lead to developing Achilles tendinosis. The occurence of this pain syndrome is highest with runners, but it often impacts ahtletes in other sports that require not only running, but a great deal of jumping, such as basketball, football, tennis, handball, etc.

Achilles tendon pain can be of either acute or chronic nature, ie. it can have a sudden onset or it can grow with a slower progress, during time. Symptoms include pain, commonly localised 2-5 cm above the connecting point of the tendon on the heel bone, which is associated to physical activity, ie. it will usually start at the beginning of the activity, decrease in intensity as the activity pregresses and get more intense after the activity. A common occurence is morning pain and stiffness in the upper ankle joint (talocrural joint). There is a feeling of tension in the tendon and the patient can not perform full range of motion during certain movements in either the ankle joint or even in other joints of the lower body, eg. during a squat where pain, stiffness and low flexibility of the Achilles tendon can limit its full range of motion.

Rehabilitaion of this pain syndrome is based on an conservative approach. In the beggining stages it is important that the level of activities that cause pain is decreased. A small pad (1-2 cm high) can be put under the heel in all footwear in order to relieve strain on the tendon. Ice application on the painful area when symptoms start developing and its use 2-3 times a day for periods of 10-15 min is used to decrease pain. Treatment mainly depends on correct diagnostics of factors that have caused pain and overload on the tendon. A longterm solution to this problem is a combination of posterior lower leg muscles eccentric strenghtening (the muscle gets elongated during its workload) and implementing different tendon and muscle stretching techniques. It is of great importance that athletes learn proper performance of both strenghtening and stretching part.

Prevention: choice of quality and proper footwear depending on the sports activity and the surface where it is performed, correct lower leg muscles strenghtening and stretching, maintaining a normal body weight, use of orthopaedic foot pads if there are certain foot deformations in question, etc.