A look at the cause and cure of Achilles tendon injuries
Achilles injuries can be, both literally and figuratively, a runner’s Achilles heel. As one of the most common injuries seen in private practice, achilles injuries most commonly occur due to overuse. The majority of tendon overuse injuries occur due to overtraining, excessive intensity or distance increase, or a change in training surface – e.g. grass to bitumen. Other predisposing factors include a lack of training variation, poorly supportive footwear and hill running. Looking at this list, most of us will fall privy to at least one of these risk factors during our running lifespan, so, how can we get on top of these niggles early and allow a return to sport as soon as possible?
At a recent sports medicine conference, return to sport for tendon injuries was a hotly debated topic and it appears the old philosophy of rest is more than just outdated. Tendons themselves respond to load eg resting a tendon (unless it’s a complete rupture of course) is counter-intuitive to the healing mechanism of the body. Unless you are having pain with every step, I prefer to recommend a change in load rather than a complete cessation of training. Provided you can get on top of pain symptoms early on, cutting back on mileage, avoiding hills and staying away from speedwork for a few weeks can sometimes be enough. While Achilles injuries are complex, here are some of the top guides I use when treating an Achilles injury:
1. Training History
When managing a tendon injury, as health professionals we need to take into account your personal running history, the length of time you’ve had the injury and the other activities in which you are involved in. For most clients, we can modify other activities outside of running to help them to keep some run sessions in their week eg the use of a heel lift in day to day footwear.
2. Phase of Repair
Tendon degeneration and repair runs in phases and as such identification of the current phase of injury is pivotal to determining how to implement changes in load. The application of appropriate exercise in the rehabilitation of your injury is also phase dependant so it is advisable to have your injury assessed by a health professional. Inappropriate loading may delay your recovery and your return to sport, and further set you back on your long term goals.
3. Foot and Ankle Mobility
As an osteopath, I am always looking to find the root cause of injury. Ankle mobility plays a key role in achilles management yet the mechanism is not year clearly understood. The achilles tendon essentially functions to transfer “push-off” force for the calf muscles to the heel bone. This force can be 3 to 6 times the body’s weight for activities such as running and jumping. If we look at the mechanics, with each step, the subtalar joint of the ankle moves up to 30 degrees, resulting in repetitive lengthening and shortening of the Achilles tendon complex. Any abnormalities in this mobility over time can predispose to overloading the achilles tendon.
4. Lower Limb Biomechanics
In addition, a limitation in the subtalar joint has been associated with what we call a tibial torsion, which can alter the line of pull of the achilles tendon. The flow on effect of this type of tibial rotation (lower leg rotation), is a femoral rotation (thigh bone). Therefore we have a change in muscle recruitment at the hip itself, which is why we always assess gait from a broader perspective. Identifying any pelvic drop (hip drop) during running which may predispose to achilles injury, can help us to reduce the risk of an injury down the track.
5. Training Variation
We tend to see a spike in achilles injuries when runners start to complete more high speed or hill based run sessions. The main reason for this is that we start to run more on our toes and forefoot for these sessions and this is a lot of work for the achilles tendon. When looking to structure your training week it is important this reflects where you are in your program and where you are wanting to head. The ideal balance for most runners is 80% low intensity to 20% high intensity training to provide the optimal conditions for endurance adaptations to occur. This means that if you are running five times a week, only one of these sessions should be speed or hill based work. Obviously there are exceptions to this rule but for the general weekend warrior, this 80/20 rule is a good starting point.
For a successful return to running, it is essential to address external factors including training load, terrain and intensity of sessions. It is equally important to not disregard intrinsic biomechanical restrictions in a well planned return to sport program. When looking at treatment and rehabilitation options, it is vital to understand not only training load, but also injury history as achilles tendon injuries are frustrating and can be debilitating. So if you are experiencing achilles pain, I always advise seeing your health professional early to ensure a smooth return to training, and not let your injury become your literal achilles heel.