(Also known as Achilles Tendinitis, Achilles Tendinopathy, Achilles Tendinosis)
N.B. Although the lastest research suggests that ‘Achilles tendinopathy’ is the more appropriate term to describe overuse injuries to the Achilles tendon (since an inflammatory response is often absent), we will use the term ‘Achilles tendonitis’ in this document as it is more commonly known.
What is Achilles tendonitis?
Achilles tendonitis (tendinopathy) is a relatively common overuse condition of the Achilles tendon. It is characterised by microscopic tissue damage, degeneration and often pain and swelling in the Achilles tendon.
The muscle group at the back of the lower leg is commonly called the calf. The calf comprises of 2 major muscles, one of which originates from above the knee joint (gastrocnemius), the other of which originates from below the knee joint (soleus). Both of these muscles insert into the heel bone via the Achilles tendon (figure 1).
Figure 1 – Relevant Anatomy for Achilles Tendonitis
During contraction and stretch of the calf, tensile and compressive forces are placed upon the Achilles tendon. When these forces are excessive due to too much repetition, prolonged or high force, damage to the tendon occurs.
Achilles tendonitis (tendinopathy) is a condition involving damage to the tendon with subsequent degeneration and disorganisation of collagen fibres (a protein giving the tendon its tensile strength). This may also be accompanied by swelling, inflammation or thickening of the tendon. These changes impair the tendon’s ability to withstand stress.
Achilles tendonitis can be classified as ‘insertional’ or ‘mid tendon’ based on the location of the changes within the tendon.
Phases of Achilles Tendonitis (Tendinopathy)
Due to an increase in load on the tendon beyond what it can withstand, Achilles tendonitis (tendinopathy) may progress through 3 primary phases:
Reactive Phase – This phase entails a short term adaptation to increasing tendon load, that thickens the tendon, reduces stress and increases stiffness of the tendon. Changes to the tendon during the reactive phase are typically reversible (with appropriate physiotherapy management). During this phase, the tendon’s structure remains intact.
Dysrepair Phase – This phase occurs if the Achilles tendon continues to be loaded excessively during the reactive phase. The dysrepair phase is characterised by changes and breakdown in the tendon structure. Formation of new nerves and blood vessels occur, resulting in heightened sensitivity and pain within the tendon. Appropriate management is essential during this phase to prevent further degradation of the tendon.
Degenerative Phase – This stage occurs in response to chronic tendon overload. Further changes and breakdown in the tendon structure take place. Collagen becomes disorganised. Additional growth of new blood vessels and nerves occur. Areas of cell death occur. The tendon may appear thickened or nodular and be at a higher risk or rupture.
Causes of Achilles tendonitis
Achilles tendonitis (tendinopathy) most commonly occurs due to repetitive or prolonged activities placing tensile or compressive forces on the Achilles tendon beyond what it can withstand. This may occurs in association with excessive:
walking or running (particularly up or down hills or stairs, or, on uneven surfaces)
jumping or hopping activities
weight lifting (e.g. loaded calf raises)
Occasionally, the condition may occur suddenly due to a high force going through the Achilles tendon beyond what it can withstand. This may be due to a sudden acceleration, a forceful jump or a direct blow to the Achilles. Achilles tendonitis may also occur following a calf or Achilles tear, following a poorly rehabilitated sprained ankle or in patients with poor foot biomechanics (e.g. flat feet) or inappropriate footwear. In athletes, this condition is commonly seen in running sports such as marathon, triathlon, football and athletics.
Signs and symptoms of Achilles tendonitis
Patients with this condition typically experience pain or discomfort in the Achilles tendon (i.e. heel region – Figure 1). In less severe cases, patients may only experience an ache or stiffness in the Achilles region that increases with rest (typically at night or first thing in the morning) following activities which place stress on the Achilles tendon. These activities typically include walking or running excessively (especially uphill or on uneven surfaces), jumping, hopping, performing heel raises or calf stretches.
The pain associated with this condition may also warm up with activity in the initial stages of injury. As the condition progresses, patients may experience symptoms that increase during sport or activity, affecting performance. Pain may also increase when performing a calf stretch or heel raise (i.e. rising up onto tip toes). In severe cases, patients may walk with a limp or be unable to weight bear on the affected leg.
Patients with Achilles tendonitis may also experience swelling, tenderness on firmly touching the Achilles tendon, weakness and sometimes palpable thickening of the affected Achilles tendon when compared with the unaffected side.
Diagnosis of Achilles tendonitis
A thorough subjective and objective examination from a physiotherapist is usually sufficient to diagnose an Achilles injury such as Achilles tendonitis. Occasionally, further investigations such as an Ultrasound, X-ray or MRI scan may be required to assist with diagnosis, rule out other conditions and assess the severity of injury.
Prognosis of Achilles tendonitis
Most patients who have had Achilles tendonitis for a short period of time (and are in the reactive phase) heal well with appropriate physiotherapy and return to normal function within a number of weeks. As the condition duration and severity increases and progresses to the dysrepair and degenerative phases, recovery can be a lengthy process and may take many months of rehabilitation. Patients with a degenerative tendinopathy have an increased risk of a sub-optimal outcome. Early physiotherapy treatment is vital to hasten recovery in all patients with this condition.
Treatment for Achilles tendonitis
For detailed physiotherapy information on the treatment of Achilles tendonitis (tendinopathy) ‘Become a Member’
Despite appropriate physiotherapy management, some patients with this condition do not improve. When this occurs the treating physiotherapist or doctor will advise on the best course of management. This may include pharmaceutical intervention, corticosteroid injection, autologous blood injection, sclerosing injection or referral to appropriate medical authorities who will advise on any interventions that may be appropriate to improve the condition. A review with a podiatrist for possible orthotics may also be indicated.
Exercises for Achilles tendonitis
The following exercises are commonly prescribed to patients with this condition. You should discuss the suitability of these exercises with your physiotherapist prior to beginning them. Generally, they should be performed provided they do not cause or increase symptoms.
Your physiotherapist can advise when it is appropriate to begin the initial exercises and eventually progress to the intermediate, advanced and other exercises. Unless otherwise stated, the addition of exercises or progression to more advanced exercises should take place provided there is no increase in symptoms.
Calf Stretch with Towel
Begin this stretch in long sitting with your leg to be stretched in front of you. Your knee and back should be straight and a towel or rigid band placed around your foot as demonstrated (figure 2). Using your foot, ankle and the towel, bring your toes towards your head until you feel a stretch in the back of your calf, Achilles tendon or leg. Hold for 5 seconds and repeat 10 times at a mild to moderate stretch provided the exercise is pain free. Perform 2 – 3 times daily.
Figure 2 – Calf Stretch with Towel
Resistance Band Calf Strengthening
Begin this exercise with a resistance band around your foot as demonstrated and your foot and ankle held up towards your head (figure 3). Slowly move your foot and ankle down against the resistance band as far as possible and comfortable without pain, tightening your calf muscle. Very slowly return back to the starting position. Repeat 10 – 20 times provided the exercise is pain free. Perform 2 – 3 times daily.
Figure 3 – Resistance Band Calf Strengthening (left calf)
For intermediate exercises that are a vital component of rehabilitation for patients with this condition ‘Become a Member’.
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<a href=”https://www.physioadvisor.com.au/injuries/achilles-heel/achilles-tendonitis/”>Achilles Tendonitis (Achilles Tendinopathy) – PhysioAdvisor.com</a><br/> Achilles tendonitis (tendinopathy) is a common injury involving tissue damage, degeneration and swelling of the Achilles Tendon. This usually occurs in association with overuse (such as excessive walking, running or jumping activities) and typically causes pain in the heel / Achilles region. Accurate diagnosis followed by an appropriate physiotherapy rehabilitation program is essential for an optimal recovery.
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