COMMON PROBLEM The Achilles tendon the largest tendon in the human body, and is very much a running-specific adaptation.
Most people are familiar with the myth of Achilles, the Greek warrior whose mother dipped him in the River Styx, making him immortal all over except for the point at his heel where she held him. Sadly for him, he was hit by a poison arrow at the heel and died. The Achilles tendon is often seen as a weak point for sports people, although rarely as drastically so as for the man himself!
The Achilles tendon is what attaches the calf muscles into the foot. You can feel the rope-like structure just above your heel bone. It is the largest tendon in the human body, and is very much a running-specific adaptation. Our closest living relatives, the great apes have a much shorter tendon than we do; they don’t run.
Research suggests that the Achilles is strong enough to carry a load of almost eight times your bodyweight when running. So how did it get such a bad reputation? And if it is specific to running, why do sports people develop problems there?
Pain in the region of the Achilles tendon generally occurs due to one of three causes: rupture, tendinosis or referred pain.
Achilles tendon ruptures are relatively rare – around seven incidents per 100,000 people – with 80 percent occurring during sport. Interestingly, only about 10 percent of those who rupture their Achilles have any history of previous problems.
A full rupture of the Achilles is a traumatic incident: the fibres snap completely and sufferers often describe a feeling of being hit or shot in the back of the leg. Indeed it isn’t unusual for spectators to hear the tendon snap from a distance.
Treatment can be surgical or conservative, but both involve a long period of immobilisation in a cast or boot and rehabilitation generally takes a minimum of six months of gradually increasing range of movement and strength prior to returning to sport.
Tendinosis is described as a degeneration of the tendon’s collagen in response to chronic overuse. If a tendon is repetitively overloaded, microscopic tears occur within the tissue, the collagen laid down in the healing process isn’t as strong as the original tissue, and therefore further micro-tears develop as loading continues.
Bearing in mind that the Achilles is a running-specific adaptation, and that it can carry eight times your body weight, it is likely the tendon is being misused, rather than overused. Recovery from tendinosis can take anywhere from six weeks to six months, with treatment initially aiming to reduce the overload by relative rest, then increasing strength using eccentric loading of the calf muscles.
Referred pain into the Achilles region can be related to lower back issues, such as a disc bulge putting pressure on a nerve in your back, or from other muscles in the lower leg. For anyone involved in running sports, the latter of these is far more likely.
Trigger points are described as hyper-irritable spots in the fascia surrounding muscles, and are associated with taut bands within the muscle.
Trigger points in the soleus and tibialis posterior muscles both refer pain to the Achilles region. In the soleus muscle they develop due to lack of use through too much sitting, prolonged ground contact time when running, and consciously trying to run on the toes.
Tibialis posterior trigger points are most common in runners with relatively immobile feet, bunions and stiff ankles, as well as prolonged ground contact time.
The treatment of trigger points can include deep massage, dry needling and the use of foam rollers or other self-treatment methods. These bands typically occur in muscles that are over used, or misused, so treatment should also look at the causes for them developing in the first place: muscle imbalances and or poor movement patterns.
A progressive strengthening programme addresses the muscle imbalance. Video analysis may be useful to assess movement patterns, and to provide drills and ‘homework’ to correct those issues; meaning you are less likely to develop those hotspots in the first place and hopefully able to get back running sooner rather than later.
Alternatively, you could just blame your mum for holding onto your ankle when she dipped you into the river of immortality.
Andrew O’Brien is a chartered physiotherapist and the owner of Wannarun Physiotherapy and Running Clinic at Westport Leisure Park. He can be contacted on 083 1593200 or at www.wannarun.ie.