The Achilles tendon is a strong tendon located at the back of the foot (Picture 1). Pain in this region is often seen in the 3rd – 5th decade of life and though very common, it is often not treated properly and therefore causing constant problems.
Achilles Tendon Anatomy
The Achilles tendon or, medically, tendo-calcaneus attaches the muscles gastrocnemius and soleus, located in the calf, to the heel bone called calcaneum. These muscles primarily function to push the fore-foot downward during walking or jumping.
In our day to day life, the Achilles tendon is exposed to stresses equivalent to twice or thrice the weight of the body, possibly causing a degeneration of the tendon and leading to two painful conditions:
- Achilles tendinosis – an inflammation of the tendon, causing pain
- Achilles tendon rupture – tear of the tendon, causing pain and disability to the affected foot.
Picture 1. Achilles tendon (tendo calcaneus)
Achilles Tendinosis (Tendonitis)
Achilles tendinosis (tendonitis) is degeneration of Achilles tendon, causing stiffness and pain during movements, like walking. Earlier, it was thought only athletes are prone to this type of injury, however, it has now been proved that repetitive use and improper footwear also seem to cause it. Pain is particularly present in the morning, especially with the first few steps after getting out of bed. Many times, pain subsides spontaneously or with mild painkillers. As a result of this self-treatment, patients visit a physician months after the origin of the ailment, making it more difficult to treat.
Achilles Tendon Rupture
Achilles tendon rupture is a partial or complete tear of Achilles tendon occuring during normal use in Achiles tendonitis, or due to an injury, often in sport. In either of the situations, the patient has a significant disability and pain, making it difficult even to walk. With partial tear or even a complete tear, the patient is still able to walk, but movements of the involved foot are not possible. Injection of steroids at the back of the foot for Achilles tendinosis or some other painful condition of the foot can cause early weakening of the tendon, and is a fairly common cause of Achilles tendon rupture.
How to Differ Between Tendonitis and Tendon Rupture?
Symptom wise, tendonitis causes only pain and some restriction of movement of the foot, but still one can walk and even run after taking painkillers. In tendon rupture, pain is minimal and not being able to walk is the main complaint.
A few simple tests help to detect if you have a tendon rupture:
- Standing on your toes on the affected side. If you are able to do this, then you are not having tendon rupture, but if this act results in sudden pain, then you could be having a partial tear.
- Squeezing calf test (Thompson test). You lie on your stomach, bend your leg 90 degrees in the knees and ask someone to squeeze your calf and observe the foot. If your foot moves up and down automatically with each squeeze, then your Achilles tendon is not ruptured.
Though these differentiations are quite specific, your orthopedician might want to confirm the diagnosis with investigations, like:
- Ultrasound of the ankle
- Magnetic Resonance Investigation (MRI ) of the ankle
Investigations, like X-ray, and neurological tests, like Electromyogram (EMG), Nerve Conduction Velocity (NCV), etc., are usually not necessary, but may be used to rule out an eventual co-existing disease.
The accurate diagnosis is the first step of getting the right treatment.
Treatment of Tendonitis
Treatment of tendonitis is mainly centered at preventing further damage to the already sore and degenerated tendon, and giving it adequate rest:
- Crepe bandage or ankle brace application during the day
- Placing the foot over an elevation (2 pillows ) at night reduces the swelling
- Range of Motion (ROM) exercises to keep the tendon active without putting any stress on the tendon
If above measures do not help, a painkiller and trypsin-chymotrypsin by mouth for a period of 15 days can be tried. The trypsin-chymotrypsin is a combination of enzymes, which help in healing musculo-skeletal tissues and reduce soreness and swelling.
Local steroid injections of Prednisolone can give a long term relief, but they can make the tendon even more vulnerable to rupture by weakening the protective response of the body. After prompt pain relief by these injections, patients frequently resume their activities, and the continued stress on the already weakened tendon can cause it to tear. So, these injections should be accompanied with adequate rest to allow the tendon to heal properly. Steroids are anti-inflammatory in action; taken as a tablet, they can cause several side-effects, but as a local injection they are safe and effective in reducing the soreness. They are frequently used in chronic painful conditions like tennis elbow, calcaneal spur, plantar fasciitis, etc.
Physiotherapy in the form of wax-bath or local ultrasound therapy is beneficial in most cases, but the effects are subjective.
Treatment of Achilles Tendon Rupture
Achilles tendon rupture almost always requires surgical management. In only a few cases of partial rupture, an immobilisation with plaster cast can be tried. The surgery consists of using a very strong suture (thread), which is braided like a pony-tail into several patterns of knots in order to hold together parts of the strongest tendon in our body.
Picture 2. Ruptured Achilles tendon – surgical repair
Infection of the wound is a frequent complication of the surgery, and even after surgery one has to remain in a plaster cast for almost 6 weeks; it may take 2-3 months for a patient to resume their daily activities. Rehabilitation can be speeded by special exercises as instructed by a physiotherapist.
Conditions Mimicking Achilles Tendon Pain
- Plantar fasciitis – inflammation of the fibrous sheet on the sole of the foot causes morning pain in the sole of the foot or at the heel bone.
- Calcaneal spur - a pointed overgrowth in the heel bone, causing severe pain similar to tendo-achilles pain. A foot X-ray is necessary to confirm the diagnosis. This condition is dramatically relieved with by wearing extremely soft footwear, which gives a protective padding to the sole of the foot.
- Ankle arthritis – a deformity of the ankle joint, commonly caused by an old ankle injury, worsening with time and causing ankle pain. An ankle X-ray to confirm the diagnosis and corrective surgery are often needed.