What is Achilles tendinopathy?
Achilles tendinopathy is characterised by degeneration of the fibres of the Achilles tendon. This can occur either directly at the insertion of the tendon into the heel bone (insertional tendinopathy), or in an area approximately 3-10cm above the insertion (non-insertional tendinopathy). It can be associated with inflammation of a bursa or tendon sheath in the same area.
What are the symptoms?
Most patients report the gradual onset of pain and swelling in the Achilles tendon without a specific injury. At first, the pain is noted after activity alone, but becomes more constant over time. The pain is made worse by jumping or running and especially with sports requiring short bursts of these activities. There is tenderness directly over the back of the tendon at the affected area. In insertional tendinopathy, the back of the heel bone is often very sore, and a bony prominence can be felt in this area. In non-insertional tendinopathy, the tendon can become quite swollen and hard. Stretching the Achilles tendon by extending the ankle past 90 degrees often causes pain.
What causes Achilles tendinopathy?
The cause is primarily a degeneration of the tendon. The average patient is in their 40s. Conditions associated with increased risk include psoriasis and Reiter’s syndrome, spondyloarthropathy, gout, familial hyperlipidemia, sarcoidosis and diffuse idiopathic skeletal hyperostosis as well as the use of medications such as steroids and fluoroquinolone antibiotics.
In some patients, it can be associated with repetitive activities which overload the tendon structure, postural problems such as flatfeet or high-arched feet, or footwear and training issues such as running on uneven or excessively hard ground.
The Achilles tendon is the largest tendon in the body. It is formed by the merging together of the soleus and gastrocnemius (calf) muscles and functions to bend the knee, point the toes down, as well as to slightly roll the heel to the big toe side of the foot. It inserts into the back of the heel bone. There may be a shelf extending off the back of the heel bone at the insertion site as well as a prominence of the heel bone in this area referred to as a Haglund's deformity, which can cause mechanical irritation of the Achilles tendon.
How is Achilles tendinopathy diagnosed?
The diagnosis is made by taking a thorough medical history and physical examination. The area of degenerative tendon is painful to touch, and the tendon itself is often enlarged and swollen. In patients with a large heel bone spur (Haglund’s deformity), forced extension of the ankle directly aggravates the tendon in cases of insertional tendinopathy.
X-rays are required to evaluate the shape of the heel bone, and may show calcification deposits within the tendon at its insertion into the heel approximately 60 percent of the time. Their presence is associated with a more guarded success rate for non-surgical treatment and a longer recovery time if surgery is performed.
Magnetic resonance imaging (MRI) remains the imaging option of choice because it can determine the extent of tendon degeneration as well as other factors such as bursitis and tendon sheath inflammation (tenosynovitis), which may contribute to heel pain.
What are the treatment options?
Non-Surgical Treatment Options
Conservative non-surgical treatment remains effective in the majority of patients, and includes non-steroidal anti-inflammatory medications, heel lifts, stretching, and shoes that do not cause pressure over the area. If symptoms persist, then night splints, arch supports and physiotherapy may be of benefit. If this fails, then application of a cast or brace (eg moonboot) with gradual return to activity is indicated. Extra-corporeal shockwave therapy has a growing evidence base for its use in Achilles tendinopathy.
Surgical Treatment Options
Surgical treatment is indicated if conservative measures have failed. Surgery removes the degenerative portions of the tendon, any bone which is irritating the tendon, and any inflamed tendon sheath or bursal tissue. If the tendon is short or contracted, then lengthening may also be necessary. The tendon attachment to the heel bone may need to be reinforced with sutures that attach directly into the bone.
Several different approaches and techniques, including endoscopy, are used to achieve these goals. There is no clear consensus regarding which is best in terms of both success and complications. In older patients or those in whom more than 50 percent of the tendon is removed, one of the other tendons at the back of the ankle (the flexor hallucis longus tendon) is usually transferred to the heel bone to assist the Achilles tendon with strength as well as provide a better blood supply to this area.
How long is recovery after surgery?
After surgery, a plaster cast or boot is worn for two weeks to allow wound healing. Once the wound has healed, a camboot is used for a further four weeks as weightbearing is commenced, with the patient coming out to start range of movement exercises. Physiotherapy to progress range of movement, lower limb strengthening and gait re-training is very important. Return to athletic activities usually occurs between eight to 12 weeks, depending on the amount of detachment of the tendon at the time of surgery. If another tendon is transferred, then recovery may take longer.
Some patients may require one to two years to recover following both surgical and non-surgical treatment. Good to excellent results after surgery are about 75 percent.