Achilles tendinopathy occurs when there is an overuse injury to the Achilles tendon (Malliaras et al. 2013). The severity of the condition may be classified along a continuum of pathology (Cook and Purdam, 2009).
The initial stage of Achilles tendinopathy occurs when there is an acute overload to the tendon. This overload may be the result of an increase in the tensile load placed on the tendon or by a compressive load (Cook & Purdam, 2009).
As Achilles tendinopathy develops, there is greater disruption to the collagen fibres that make up the tendon which can alter the capacity of the tendon to handle the load.
The Achilles tendon is understood to be able to transition between a normal(asymptomatic) tendon and asymptomatic tendon, and vice versa, based on the amount of load placed on the tendon. Current research has shown that inflammatory markers do not play a significant role in tendinopathy (Paavola et al., 2002)(Alfredson & Cook, 2007) which questions the
use of anti-inflammatory medication as a treatment.
ANATOMY and BIOMECHANICS
The Achilles tendon is located at the posterior inferior aspect of the leg and connects the
Gastrocnemius and soleus muscles to the calcaneus. The role of the tendon is to transmit forces between the calf muscles and the calcaneus (Magnusson et al., 2010)(Cook & Purdam, 2012). This allows for concentric and eccentric forces of the calf muscles to control ankle movements during everyday activities. Like other tendons in the body, the Achilles tendon is composed of a high percentage of type I collagen allowing it to handle large tensile forces (Levangie & Norkin, 2005).
SYMPTOMS
An individual with Achilles tendinopathy will often experience pain centrally along the tendon. This pain may be along the mid part of the tendon, termed mid-portion Achilles tendinopathy, or at the insertion, termed insertional tendinopathy. Achilles tendinopathy may present with swelling or thickness of the tendon and an individual will experience impairment in their physical activity generally due to pain (Mallaris et al, 2013) (Magnusson et al, 2010). Individuals with Achilles tendinopathy may initially be able to continue playing sport (Silbernagel & Crossley, 2015) with pain generally first reported after activities involving high loads to the Achilles tendon. In later stages of the tendinopathy, pain may be reported during activities and at rest (Paavola et al, 2002).
DIFFERENTIAL DIAGNOSIS
Differentiation between mid-portion and insertional Achilles tendinopathy is important as it can alter the rehabilitation pathway. Other potential causes of posterior leg/heel pain must also be considered before commencing treatment. Alternative causes to pain may be retrocalcaneal bursitis, posterior ankle impingement, flexor hallucus longus tendinopathy/tear, plantaris restrictions or referral from neural structures (Brukner & Kahn, 2009).
TREATMENT
Research has consistently recommended progressive exercise loading programs as the initial treatment of Achilles tendinopathy (Silbernagel & Crossley, 2015). Tendon loading programs allow for remodelling of the tendon and improvements in its ability to handle the load. The type of loading program for treating Achilles tendinopathy has been recommended to be dependent on the current stage of tendinopathy.
For a reactive (acute) tendinopathy the Achilles tendon may require appropriate time to adapt to the overload which can involve modified rest from tendon loading activities (Cook & Purdam, 2009).
Often isometric exercises are used as an early pain management method for tendinopathies.
Alfredson’s eccentric loading program (Alfredson et al, 1998) focusses on providing the Achilles tendon with the eccentric load to improve the strength of the Achilles. The program is based on the intensity of pain experienced by the individual. A recent review by Malliaris et al (2013) indicated that while an eccentric loading program has as much evidence to support its use, there is limited evidence to support this program compared to other loading programs. This is because the Alfredson program only focuses on the eccentric component when the tendon must also adapt to concentric loads.
The Silbernagel Combined loading program (Silbernagel et al, 2001) is a loading program that incorporates eccentric-concentric, eccentric and then faster loading movements to rehabilitate Achilles tendinopathy. This program has gained support as it has a greater progressive adaptation of the tendon to a full return to activities.
In addition to focussing on the load management of the Achilles tendon, it is important to rehabilitate restrictions elsewhere along the kinetic chain and alter external factors that influence the tendon.
Some of the latest research into tendinopathy rehabilitation also discusses the potential to incorporate neuroplastic tendon training to improve the neuroplasticity of the motor cortex and muscle activation (Rio et al, 2015). In a small number of individuals, conservative treatment may be unsuccessful and surgical opinion may be sought (Alfredson & Cook, 2007).
The five best tips for Achilles tendinopathy
- Be sure to increase your training load over several sessions gradually. Tendons respond best
to gradual increases in load and by doing so can reduce the chances of developing Achilles
tendinopathy.
- Avoid active stretching of the calf and Achilles when symptoms are present. This may cause a compressive load on the Achilles tendon and increase symptoms. A good alternative is
using a foam roller to release the calf.
- Don’t let your pain linger for weeks. If the Achilles pain is not settling, see your physiotherapist for an individualised exercise program.
- Do not have complete rest from your exercises. Tendons do like load and finding alternative
forms of exercises can be beneficial.
- Ensure your rehabilitation progresses to incorporate the highest level of load required by
your Achilles tendon.
ANATOMY IMAGES OF THE ACHILLES TENDON AND CALF MUSCLES
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REFERENCES:
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Magnusson, S. P., Langberg, H. and Kjaer, M. (2010). The pathogenesis of tendinopathy: balancing
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Silbernagel, K. G. and Crossley, K. M. (2015). A proposed return-to-sport program for patients with
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