Achilles tendon injury – from tendinopathy to rupture

Achilles tendon problems are evident across all sports – predominately running and jumping based sports. They can sideline an athlete for months, frustrating them at every attempted return with its sluggish recovery. The causes and the process behind the problem have been the subject of some debate over the years. However there has been some great evidence being produced here in Australia over recent years. Luckily the solution is far more straightforward and follows a fairly predictable script.

Achilles tendinopathy vs Achilles ruptures

It’s worth clarifying that Achilles tendinopathy, a slowly building ache in the Achilles tendon, and Achilles rupture, a sudden snapping of the Achilles tendon, rarely go hand-in-hand.

Achilles ruptures

Around 2/3 of ruptures do not have any pain or symptoms in the Achilles prior to rupture.

Conversely, someone with a gradual ache has only a slightly increased risk of rupture.

This needs to be mentioned because hesitancy or trying to “protect” the Achilles during the recovery phase leads to altered loading of the Achilles and re-aggravate the tendinopathy.

Achilles tendinopathy

The process behind Achilles tendinopathy is still not 100% clear but it appears the body’s own healing mechanism is at fault.

Also called Achilles tendinosis and Achilles tendinitis (although this term is incorrect as it refers to an inflammatory condition), there is a proliferation of blood vessels inside the tendon, presumably to try to repair the injured area. The problem here is that the Achilles has very little blood supply and blood vessels in its normal state.

When these extra vessels begin to develop, they occupy space where the tendon fibres used to be and cause more of a problem.

This leads to more of a reaction from the body, more blood vessels and…..well, you get the picture. It’s a nasty cycle.

The Cause

The causes behind this process fall into two primary categories: increased force and abnormal direction of force.

The first cause actually refers to shock loading rather than just overall force. The shock loading is the rate of force combined with the length of time that the force is applied. Higher forces or shortened application times will increase the shock loading. In this category, we have runners putting on weight (the faster the weight gain, the greater the risk of Achilles tendinopathy), losing their normal ankle movement (seen after ankle sprains) or altering their running gait.

The second cause, abnormal force direction, refers to the orientation of force through the Achilles. We see this cause with poor foot mechanics from old/inappropriate shoes, lack of muscle support at the ankle (after injury or holiday break from running) and altered gait patterns (often seen when trying to avoid another injury by changing the angle of the foot). While you need at least one cause to start the problem, your chances of Achilles issues increases with age (due to stiffening of the tendons), high heels, poor diet and some systemic conditions.

For part 2 of this article on treatment and fixes, click here.

Written by

Tim O’Grady

Tim is a Physiotherapist who specialises in football/Rugby and golfing injuries. Tim doesn’t believe that rest will make you a better athlete and he focuses on performance-based rehab methods. Tim is also qualified in golf biomechanics and injuries.

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