Achilles Tendinopathy

12 June 2021

Pain in the back of the heel is a very common complaint amongst athletes whose sports require quick, sudden movements. This pain is due to the sudden, forceful pull of the calf muscle onto the Achilles tendon. This in turns pulls onto the calcaneal bone (heel bone) of the ankle. This pain is known as Achilles Tendinopathy.

Anatomy Of The Achilles Tendon

Achilles Tendinopathy

The Achilles tendon is the biggest and thickest tendon. Like all tendons, it comprises of mainly fibrous tissues which does not stretch under strain and it joins the calf muscles to the calcaneal bone of the ankle. The role of the Achilles tendon is to bring about plantar flexion (downward pointing) of the ankle, push-off phase of walking and running, and also to aid in shock absorption on jumping. The blood supply to this tendon comes from the calf muscles (gastronemius and soleus) proximally, and distally from the tendon-bone insertion. These sites are also the areas where there are the most number of nerve endings. This explains why these are the common sites of pain.

Causes Of Achilles Tendinopathy

In the United States, about 230 000 of Achilles injuries are due to overuse, leading to unusually high strains. The strain that the Achilles tendon undergoes ranges from 3 times one’s body weight (in walking) to as high as 12 times (in jumping). Due to such high levels of strain, injuries tend to be multi-factorial: poor training technique, structural abnormality, improper footwear. The table below indicates some common examples that increase the risk of injury.

Poor Training Technique Structural AbnormalityImproper Footwear
  • Sudden increase in training frequency
  • Sudden change in training terrain
  • Inadequate warm-up
  • Incomplete rehab before returning from injury
  • Limb length discrepancy
  • Tight calf muscles
  • Under- or Over-pronation
  • Weak calf muscles
  • Calcaneal varus/ valgus (turning in / out towards midline of heel bone)
  • Poor shock absorption
  • Wrong type of footwear for foot type
  • Worn out shoes

Nature Of Pain

Achilles tendinopathy normally starts off as morning stiffness and pain on the first step either on the bony insertion or at the muscle-tendon junction. The tendon may also feel sore. As the condition worsens, there might be pain on running and in severe cases, walking would also be painful. If ignored, it might lead to a partial or complete rupture of the Achilles tendon which would require immediate surgical intervention and a long rehab process.

Conservative Management For Achilles Tendinopathy

Stretch your tight calf muscles and do calf raises to prevent achilles tendinopathy. This is to strengthen their calf muscles. Ultrasound, TENS, IFC (Interferential Current) are common physiotherapy modalities to manage the pain. To manually loosen up the tightness in the calf and at the tendon-bone insertion, deep tissue mobilization is used. In recent years, research has advocated eccentric loading of the tendon to further strengthen the tendon. Eccentric loading is the strengthening of the tendon while it is being lengthened. Doing calf drops slowly has been incorporated into the rehab of Achilles tendinopathy. Ultrasound guided ESWT (Extracorporeal Shock Wave Therapy) may be employed to stimulate revascularization of the tendon at the pain site. This is if pain is stubborn and does not respond to rehabilitation. Acupuncture to manage the pain has also been tried, with varied success.

Prevention Is Better Than Cure

Regular stretches, proper warm-up and proper biomechanics can prevent achilles injury. Choosing the right kind of footwear that supports your arch and gives adequate cushioning can help reduce the strain and loading of the tendon. Staying in shape and proper progression of one’s training is the best way to prevent Achilles injury.