The Achilles tendon, also called the calcaneal tendon, connects the triceps surae (calf muscle comprising the medial and lateral gastrocnemius and the soleus) to the calcaneum (heel bone located at the back of the foot). It is the thickest, most powerful tendon in the body and is very reactive as it contains numerous major nerve endings. It transfers the power generated by the contracting muscle enabling the extension of the ankle and push-off, and absorbs energy on landing. It is therefore subjected to significant strain and stretching.
Achilles tendon inflammation or Achilles tendinitis, is common as this tendon is under constant strain when we move. The inflammation can be linked to natural aging, but also to overuse characteristic of sports activities, in particular running.
Different forms of Achilles tendonitis
Tendonitis of the midpoint of the tendon
Insertion tendinitis (tenoperiostitis: damage to the junction with the bone; myotenditis: damage to the junction with the muscle).
Tenosynovitis (inflammation of the synovial tendon sheath)
Tendino-bursitis (inflammation of the end of the tendon and the bursa located between the bone and the tendon; the synovial fluid secreted by the bursa facilitates movement).
Aging: Cell degeneration and poorer vascularization linked with aging contribute to tendon deterioration. Less flexible and less resistant on exertion, the tendons become more vulnerable to inflammatory damage.
Intense sports activities exert excessive strain on the tendons resulting in microtraumas and significant rubbing with other tissues in the joint. Ultimately, inflammation develops. Wearing worn shoes or shoes ill adapted to the activity or the terrain, or athletes adopting inappropriate positions or not warming up, stretching or drinking enough heightens the risk.
Traumas: Violent impacts or sudden, sharp changes in direction can also result in tendinitis. In extreme cases, it can result in immediate rupture.
History of joint damage and malformations: the tendons are an integral part of the joint structure in the same way as the muscles or the ligaments. Together they ensure joint stability and good biomechanical function. So when a part is faulty due to damage (e.g. ankle sprain) or a malformation (flat foot or too arched resulting in plantar statics disorders) the forces are not correctly distributed. This can put abnormal strain on the tendon and accelerate the onset of inflammatory damage.
Antibiotics: some antibiotics of the quinolone family can be the direct cause of Achilles tendinitis.
Pain: Located at the back of the heel, it is systematic and is the main symptom. It develops progressively. Firstly, the subject experiences pain in the heel after training or physical exertion that ceases at rest. It then becomes particularly intense when beginning any physical exertion, as the tendon is stretched. The pain gradually becomes persistent on exertion, and can even lead to limping. The tendon is also sensitive to touch.
Signs of inflammation: They are not systematic, but include redness, heat and edema (swelling) around the Achilles tendon.
Nodules and thickening: Small cysts and thickening of the tendon may be observed during healing. They are often a sign of abnormal healing and weaken the original tissue. To avoid relapses, even rupture, stretching exercises are necessary for the tendon to recover its flexibility.
Stiffness: This is generally a sign of chronic inflammation.
Rupture: More than just a symptom, it is a complication of Achilles tendon inflammatory damage. It can occur at the junction with the muscle or the bone or at the midpoint. Ruptures can also occur during a violent trauma.
To avoid it becoming chronic or resulting in rupture, Achilles tendinitis must be treated effectively.
Rest is the initial treatment for Achilles tendinitis. The foot must be relaxed and maintained toes pointing down (plantar flexion). Walking must be limited and should be assisted by wearing shoes with a small heel or orthopedic insoles. Sport should be stopped for three to six weeks according to the severity of the damage.
Anti-inflammatories: gel, for local application, or tablets can be prescribed to help reduce the inflammation and relieve the pain.
Rehabilitation: It initially involves pain relief and physiotherapy techniques such as electrotherapy. Exercises with the physiotherapist are then essential to prevent relapses, notably stretching exercises (to restore optimal tendon flexibility) and muscle tone reinforcement. Sports activities should be resumed gradually.
Surgery: This ensures lasting tendon repair, but is only performed if conventional treatments fail (with chronic, painful damage that impairs daily activities) or in athletes when the damage prevents them from returning to sports activities. It can consist in the ablation of scar tissue or cutting the damaged part of the tendon and attaching the healthy ends. It is the only option in the case of total rupture.
Stem cell injection and PRP therapy (platelet rich plasma) are effective treatments for Achilles tendinitis, enabling rapid and effective recovery. These techniques are becoming increasingly common.