Introduction

In some sense, all modern humans are at a heightened risk of ankle and Achilles issues because we live most of our lives on extremely hard, flat surfaces. The constant jarring of hard flat ground is a major source of strain on our Achilles over the course of a lifetime and it predisposes us to Achilles pain and tendinopathies. Nonetheless, it is generally only once other factors come into play that Achilles pain becomes a significant issue.

Faulty Movement Patterns

The asymmetric presentation of 99% of Achilles pain cases requiring treatment potentially offers some deep insight into the true underlying nature of Achilles pain causes. If you live 40 years and one day find yourself with one very painful Achilles tendon, it means that despite having done exactly the same mileage as your other Achilles tendon it has sustained some damage. Sometimes, that damage was sustained in a very obvious major injury moment. But in many other cases, some faulty movement patterning has crept into the millions of steps you take a year and gradually caused strain to the tendon.

Computerised gait analysis easily identifies the ‘wheel alignment’ issues that cause so many Achilles tendon pain cases. From there, specific rehab solutions can be tailored to improve gait and prevent further deterioration of the Achilles in the long term.

Overuse & Achilles Tendon Pain

The Achilles tendon is a power-generating tendon crucial in lower limb movements. One of the most common causes of Achilles Tendon Pain is overuse/repetitive strain injuries (RSI). The frequency of RSI becomes substantially higher in individuals who participate often in high-impact sports involving running, twisting, and jumping. The physical demand of Achilles causes alterations in the structure and mechanical function. Over time, this eventually leads to microtears forming in the Achilles paratenon (a sheath of connective tissue surrounding the tendon), causing Achilles pain, localised swelling, inflammation, reduced range of motion in the ankle joint, and Tendonopathy. Suppose the underlying cause behind repetitive strain is addressed. In that case, these microtears can become scar-like in appearance and cause chronic (3+ months) Achilles pain.  

Poor Footwear & Achilles Tendon Pain

Poor choices in footwear can directly cause Achilles pain. The characteristics that define poor footwear include lack of cushioning, poorly suited fit to the foot, poor ankle stabilisation, and limited ankle control. Furthermore, footwear choices that have excessively raised or lowered heels that place the Achilles in a flexed or extended position can damage the tendon over time. Studies have shown that individuals frequently wear high heels are at higher risk of developing shortened Achilles. Poor, unaddressed footwear can result in Achilles Tendon Pain, repetitive strain to the Achilles Tendon, Achilles swelling, and inflammation. 

Age and Achilles Tendon Pain

From age 30 years and over, the risk of developing Achilles Tendon Pain starts to increase. The most common group of Achilles tendon pain and ruptures is middle-aged men, especially those who participate in sports frequently. Age-dependent physiological changes to the Achilles tendon include reduced oxygenated blood flow to the Achilles tendon, increased tissue stiffness, dysfunctional regenerative capacity, and decreased superficial fibre size of the Achilles tendon. Without effective treatments such as shockwave therapy, previous injuries to the Achilles in our younger years can return, causing Achilles pain, swelling, inflammation, and even plantar fasciitis.  

Rest assured that advancing years are not a sentence for Achilles tendon pain. We can heal and rehabilitate Achilles tendon issues at any age. Even some of the oldest patients with Achilles tendon pain regularly make full recoveries with tht right treatment and rehabilitation.

Sudden Increase in Activity and Achilles Tendon Pain 

The Achilles tendon is the largest tendon in the body. It connects the calf muscles (Soleus and gastrocnemius) to the calcaneus (heel bone), allowing for a wide range of lower limb movement. The Achilles tendon requires daily use or load to remain healthy. When we stay sedentary for long periods, the underload of the Achilles causes the tendons to break down and weaken. Over an extended period, the collagen fibres in the Achilles start to bundle, restricting movement and causing Achilles pain. When someone spontaneously starts to exercise again after a long break, putting rapid demand and load onto the Achilles tendon through sharp, sudden movements can cause Achilles tendinopathy, partial or complete Achilles tendon rupture, or Achilles pain. 

Poor Biomechanics and Achilles Tendon Pain 

Biomechanics is: ‘Mechanics applied to biology, and mechanics itself is the response of bodies to forces or displacements.’ When we have good biomechanical movement of the lower body, the risk of developing Achilles pain substantially decreases. There are multiple causes of the deterioration of someone’s biomechanics, and one of the most common is overpronation (flattening of the arch in the foot). People who overpronate tend to have higher incidences of Achilles pain or Achilles tendinopathy; this is mainly due to causes. Firstly, excessive forces being placed on the medial aspect of the tendon cause microtear formation and, eventually, scar tissue to develop. Secondly, asynchronous movement between the foot and ankle in each leg causes a subsequent ‘wringing‘ effect. It is believed that over time, this wringing effect causes elevated tensile strength and vascular impairment of the Achilles tendon and paratenon. 

Achilles Tendon Rupture and Achilles Pain

Achilles Tendon Rupture is defined as either a full or partial Achilles tendon rupture. The injury occurs predominantly in adults between 30-50 years old. Acute or immediate ruptures present with an audible pop or snapping sound. The injury occurs when the stretch or load placed upon the Achilles tendon exceeds its tensile capacity. While sports and high-impact exercise are some of the most common culprits, simple falls or ankle sprains can cause Achilles ruptures. Interestingly, individuals who have had repeated steroid injections into the Achilles tendon are at substantially higher risk of developing an Achilles tear. Some of the most common symptoms of Achilles pain include pain in the Achilles during movement (walking, stair use, running, etc.), localised swelling/bruising of the Achilles tendon, and tenderness at the exact location of the tear. 

Bone Spurs and Achilles Pain

While there are many causes behind why Achilles pain can develop, individuals who have bone spurs around the heel are at higher risk of Achilles pain. While traditionally manifesting as heel pain, the Haglund deformity can cause Achilles pain and rupture. Haglund deformity is an abnormal bony protrusion above the back of the heel, which can increase pressure on surrounding bony structures, leading to issues such as Achilles tendon degeneration, Achilles inflammation, and Achilles pain. When these conditions occur together, it’s termed Haglund syndrome. Interestingly, clinicians have noticed that some patients diagnosed with plantar fasciitis may also experience pain in the back of the heel. Evidence suggests a direct biomechanical relationship between the Achilles tendon, plantar fascia, and heel bone (calcaneus).