There are numerous risk factors that increase the probability of a person developing Achilles tendinitis. Commonly a combination of a couple of factors leads to a problem and not just one. I am sure you all have heard the popular “too much, too soon” .Usually one of the main causes of Achilles tendinitis is putting too much load on the tendon for long time, without allowing enough time for the tendon to recover.
These are the different possible causes and risk factors according to the clinical guideline of Achilles tendinitis by Christopher R. Carcia et al.:
- Poor mobility in the foot and ankle:
- Abnormal ankle dorsiflexion range of motion (motion of your foot upwards at your ankle). Either decreased or increased. People with decreased dorsiflexion with the knee extended are supposed to experience increased tension on the Achilles tendon. It is not clear still how an increase in dorsiflexion range of motion increases this risk though.
- Abnormal subtalar joint ( joint of the foot between the heel bone and the talus or rest of the foot) range of motion, increased or decreased, as the Achilles tendon won´t be able to move normally, it would move either more or less than it should.
- Decreased ankle plantar flexion (motion of your foot downwards at your ankle) strength, in other words, weak calf muscles.
- Increased foot pronation (when your ankle goes inward and your arch tends to collapse) which is believed to decrease blood flow to the Achilles tendon. This is commonly called overpronation or “feet which roll in”. When the foot rolls in, the lower leg rotates inwards causing twisting stresses on the tendon. This is what happens to people with flat foot (pes planus).
2. Leg length discrepancy and having a high-arched foot (pes cavus), which will produce a misalignment which means less blood flow and,therefore, malfunction of the tendon.
3. Training errors and faulty equipment:
- Increase in mileage, returning from a “layoff”. This increase should be little by little, not starting training at the point you left it.
- Increasing the intensity of your training and how often you train. Resting days are very important as you have to let your body recover from exercise.
- Running up hills – the Achilles tendon has to stretch more than normal on every stride. This is fine for a while but will mean the tendon will fatigue sooner than normal.
- Inappropriate footwear: old shoes, not the appropriate shoes for your landing when exercising, high heels which shorten the tendon and calf muscles or flat running shoes which are thought to stretch the Achilles tendon beyond its normal range which places an ‘abnormal’ strain on the tendon.
- Poor training or exercising techniques – for example, poor running technique.
- Poor flexibility – for example, having tight or underdeveloped hamstring (thigh) muscles.
- Training or exercising on hard surfaces.
4. Environmental factors
Cold temperatures may increase the friction between the Achilles tendon and the surrounding tissues, thereby increasing the likelihood of developing symptoms associated with Achilles tendinitis.
5. Obesity, hypertension, hyperlipidemia, and diabetes are also associated with Achilles tendinitis. Also, this injury is more common in people over 35 years old.
In a recent study The pathogenesis of Achilles tendinopathy: a systematic review by Magnan B. et al. they speak of heterogeneity of the possible causes of this injury.
Know the treatment of Achilles tendinitis here.
If you have any questions, do not hesitate to contact me on The Physical Therapy, Physiotherapy Clinic based in Southampton, and I will be happy to help you.
You can read this post in Spanish Tendinitis aquílea: causas from my Spanish blog La Fisioterapia.net.