The Achilles
tendon is the largest and strongest tendon in the
human body. It is a tough band of fibrous tissue which inserts onto the
calcaneus of the foot. The Achilles tendon is the common tendon to the
gastrocnemius and soleus calf muscles. When these muscles are contracted, the
Achilles tendon pulls on the calcaneus causing plantar flexion of the ankle.
This is a common movement which makes walking, running, jumping and standing on
toes possible. The Achilles tendon is said to withstand forces up to seven
times one’s body weight, showing how much force the Achilles tendon is made to
withstand during sporting activities.
Achilles
Tendinitis is a condition which involves the inflammation of the tendon
surrounding the ankle joint. Tendinitis within the heel complex is either due
to a single cause, or may involve a variety of mechanisms. Although the
Achilles tendon is an extremely strong structure and able to withstand large
forces placed on it, it is still vulnerable to injury. This is due to a large
amount of tension placed on it, as well as tendons having a limited amount of
blood supply.
Achilles
tendinitis is an inflammatory condition which involves the degeneration of the Achilles
tendon. This is a result of micro tears which have developed within the
structure which directly causes instability and a decrease in the tendons
tensile strength.
There are two
types of Achilles tendinitis:
- Acute Achilles Tendinitis
This
is usually the result of abrupt or sudden onset, with the individual
experiencing moderate pain 2 – 3 cm proximal to the tendons insertion on the
heel. The pain is pinpoint tenderness and pain will increase when palpated.
- Chronic Achilles Tendinitis
This
is generally an injury which occurs from overuse. Chronic Achilles Tendinitis
exhibits a similar pain to Acute Achilles Tendinitis except the pain is usually
at the insertion of the Achilles tendon. This injury generally occurs from
repetitive micro trauma to the tendon and if left untreated, it could progress
to an Achilles Tendon Rupture.
Aetiology:
It has been
highly speculated that runners are more susceptible to Achilles tendinitis due
to the repetitive micro trauma. This micro trauma is produced by:
1.
Eccentric Loading of fatigued muscles
2.
Excess pronation which produces a whipping
action of the Achilles tendon
Therefore, all
Achilles tendon injuries tend to be a result of either structural or dynamic
disturbances of the lower leg. The main cause of Achilles tendon complex is due
to overuse/overtraining.
Causes:
- Overuse/changes in training
- Ageing
- Biomechanical faults (Pronation)
- Tight calf muscles
- Lack of ankle instability
- Inappropriate show wear (resulting in biomechanical faults)
Signs and
Symptoms:
Unless acute
Achilles tendonitis, symptoms tend to develop gradually and become worse over
time.
- Local and tender pain in Achilles which tends to increase with specific activities
- Crepitus (Grating or crackling sensation within the tendon upon movement)
- Redness/swelling around the area
- Affected tendon may appear thicker
- Stiffness in tendon in morning which gets better with movement
- Pain experienced with active or passive stretching
- Reduced flexibility
- Weakness and pain when standing on toes
Exercise as
treatment:
Due to the Achilles
tendinitis being an overuse injury, it is important to reduce activities that
place strain on the Achilles tendon. Research has found that there are passive
as well as active methods which can be prescribed to treat Achilles tendinitis. Aggressive stretching
of the Achilles tendon complex should be implemented and incorporated into the
training program to loosen the calf muscles and relieve the tendon of some of
the tension placed on it. Exercises can be done to improve one’s biomechanical
faults such as pronation which can help reduce the strain on the Achilles
tendon.
