Here’s a few facts about the Achilles tendon before we discuss tendinopathies:
- The Achilles tendon is a thick band of connective tissue that joins the calf muscles to the heel bone
- The function of the Achilles tendon is to absorb shock and store energy
- The calf muscles and Achilles tendon are responsible for 80% of our power production when walking (pushing off one leg)
- Depending on the individual, this tendon can withstand around 500kg of force before it ruptures
- The Achilles tendon has quite poor blood supply in comparison to other tissues, which can often delay healing in the event of an injury
WHAT is a tendinopathy and how does it manifest?
With overuse or repetitive strain, the physical properties of the Achilles tendon can change, including the arrangement and structure of the fibres of the tendon. This reduces the tendon’s ability to tolerate load and tensile force.
SYMPTOMS:
- Pain localised to the back of the ankle often worse with walking, running or jumping activities – this pain can be quite close to the heel bone or slightly higher depending on which portion of the tendon is affected
- A grating noise or creaking feeling (crepitus) when moving the ankle
- A feeling of stiffness in the tendon
- There can also be localised swelling to the ankle or foot
STAGES of a tendinopathy:
- Reactive – this is the first stage of a tendinopathy and commonly occurs as a result of a recent increase in physical activity or training load. Overloading the Achilles tendon repetitively above its normal load tolerance can cause micro-traumas and create excessive frictional forces between the fibres of the tendon. This can also create inflammation of the layer of tissue that surrounds the tendon.
- Degenerative – if a reactive tendinopathy is not allowed sufficient time to be offloaded and then gradually re-loaded with the appropriate exercise therapy, it can progress to a degenerative tendinopathy. At this stage, extensive changes have occurred in the tendon involving disorganisation and separation of the collagen fibres. It has been suggested that the changes at this stage become irreversible and there is a poor prognosis for tendon healing.
Aside from overuse or repetitive strain, there are a variety of other CONTRIBUTING FACTORS in the development of an Achilles tendinopathy, including:
- Poor footwear causing over-pronation (flattening of the arch of the foot) during walking/running – this can cause excessive shearing forces on the Achilles tendon
- Poor hip stability and control – lack of strength and stability in the hip can have impacts further down the chain on the knee and ankle
- Research has shown that metabolic factors such as decreased metabolic activity and obesity can contribute to the development of an Achilles tendinopathy
TREATMENT:
- Exercise therapy – this will consist of gradual increases in resistance, repetitions and speed of movement to progressively reload the tendon
- As you progress through your rehabilitation, the type of exercises will change depending on your sport or the activities you are looking to return to
- Exercise therapy will also address any weaknesses further up the chain around the hip, thigh and pelvis that may be contributing factors
- Shockwave therapy – designed to promote a pro-inflammatory healing process and improve the turnover of new fibre regeneration
- Orthotics/taping – to support the arch of the foot and avoid over-pronation and poor positioning