Achilles Tendinopathy

What is the Achilles tendon?

This tendon is the thickest tendon in the human body and connects the gastrocnemius and soleus muscles (your calf muscles) to your heel bone (calcaneus). The Achilles tendon can withstand large tensile forces but can be susceptible to damage with repetitive use and overload.

What is a tendinopathy?

A normal tendon consists of tightly bundled, parallel collagen fibrils, known as the extracellular matrix. The extracellular matrix also normally contains around 4.5 % other various proteins. In tendinopathy, the collagen fibrils become more and more disorganised and other changes take place, such as abnormal cell numbers, abnormally prominent blood vessels and an increase in matrix proteins. These tendon changes can be divided into three stages:

1. Reactive tendinopathy: this is the non-inflammatory response of tendon cells and matrix proteins to an acute tensile or compressive overload. In this stage tendon cells become activated and there is an influx of repair proteins which results in a short-term thickening of a portion of the tendon.

2. Tendon disrepair: collagen begins to separate, and the matrix becomes disorganised.

3. Degenerative tendinopathy: this is the “end stage” and areas of cell death are evident. At this stage the tendon may be prone to rupture.

What are the symptoms of Achilles Tendinopathy?

Achilles tendinopathy is an overuse injury, as such it presents with a gradual onset of pain. The most common site of pain is over the midportion of the Achilles tendon, but pain can also sometimes be felt over the insertion point into the heel bone. Often the pain is noticed first thing in the morning and is painful when commencing activity. In the early stages, the pain will often subside with activity but then become painful and stiff again once the body has cooled down.

What are risk factors for developing Achilles Tendinopathy?

Generally speaking, most cases of Achilles tendinopathy appear after a sudden increase in training volume with insufficient periods of recovery. Biomechanical factors such as poor calf strength, reduced knee flexor strength, too much or not enough ankle range of motion have been associated with the development of Achilles tendinopathy.

Approximately 4.0% of patients with Achilles tendinopathy subsequently sustained a rupture. People aged 50–59 years are most at risk.

How do we rehabilitate Achilles Tendinopathy?

Many studies have shown that a progressive exercise program prescribed by your physiotherapist can be very effective in treating Achilles tendinopathy. The effects of an exercise program on recovery from Achilles tendinopathy have been shown to be far superior to the “wait and see approach”.

There are four stages for rehabilitation, with the goal of progressively loading the tendon:

STAGE 1- Pain relief and isometric exercises- activating calf muscles without moving the ankle joint.

STAGE 2- Isotonic strength and endurance- once pain has settled down, progress to slow eccentric and concentric calf raises with body weight resistance.

STAGE 3- Energy storage exercises- gradually placing faster loads on the tendon through exercises such as slow skipping and stair climbs.

STAGE 4- Energy storage and release exercises- increase in speed of exercises, faster skipping, running and change of direction drills.

References

• https://www.physio-pedia.com/Achilles_Tendon

• Brukner, P., Clarsen, B., Cook, J., Cools, A., Crossley, K., Hutchinson, M., McCrory, P., Bahr, R., Khan, K. and Brukner, P., 2020. Brukner & Khan's clinical sports medicine. 5th ed. New South Wales: McGraw-Hill Education Australia, p.865-879.

• Rhim HC, Kim MS, Choi S, Tenforde AS. Comparative Efficacy and Tolerability of Nonsurgical Therapies for the Treatment of Midportion Achilles Tendinopathy: A Systematic Review With Network Meta-analysis. Orthop J Sports Med. 2020 Jul 16;8(7):2325967120930567. doi: 10.1177/2325967120930567. PMID: 32728589; PMCID: PMC7366412.

• Martin RL, , Chimenti R, , Cuddeford T, , et al.. Achilles pain, stiffness, and muscle power deficits: midportion Achilles tendinopathy revision 2018. J Orthop Sports Phys Ther. 2018; 48: A1– A38. https://doi.org/10.2519/jospt.2018.0302

• Yasui Y, Tonogai I, Rosenbaum AJ, Shimozono Y, Kawano H, Kennedy JG. The Risk of Achilles Tendon Rupture in the Patients with Achilles Tendinopathy: Healthcare Database Analysis in the United States. Biomed Res Int. 2017;2017:7021862. doi:10.1155/2017/7021862