Clinical Topic A-Z Clinical Speciality

Achilles tendinopathy

Achilles tendinopathy
D052256Tendinopathy
D000125Achilles Tendon
InjuriesMusculoskeletal
2010-04-19Last revised in April 2010

Achilles tendinopathy - Summary

Achilles tendinopathy is a broad term used to describe predominantly degenerative conditions that cause pain, swelling, weakness, and stiffness of the Achilles tendon.

It is one of the most common injuries in sport.

Repeated overloading of the tendon causes degeneration and disorganization of collagen fibres, increased cellularity, increased ground substance, and neovascularization. Tendinopathy is thought to occur when there is an imbalance between the pathological changes and the regenerative changes that occur in response to injury.

Complications include tendon rupture, time off work, and decreased participation in sports.

A diagnosis of Achilles tendinopathy is usually established on clinical grounds alone.

Pain is usually located in the middle third of the tendon; pain and stiffness are worse first thing in the morning; pain is usually felt after exercise but may also occur during exercise. Runners tend to experience pain at the beginning and the end of training, with a period of diminished discomfort in between.

Examination may show tenderness (usually located 2–6 cm proximal to the insertion at the heel), heat, crepitation, localized thickening, and nodularity in the tendon (more common in the chronic phase).

To manage Achilles tendinopathy in primary care:

An explanation that symptoms normally take 3–6 months to resolve should be offered.

Underlying causes and contributory factors should be identified and managed. Quinolone antibiotics should be discontinued.

Cold packs or ice should be recommended after acute injury.

Simple analgesia (either paracetamol or ibuprofen) should be recommended for pain relief.

An initial period of rest or relative rest (stopping high impact activities, such as running) should be recommended until the pain subsides. Exercise can be restarted when pain allows. Complete rest can be counterproductive if it is prolonged.

A daily programme of Achilles tendon stretching exercises and strength training should be considered. Referral to physiotherapy may be required.

Referral for a biomechanical assessment should be considered (depending on local services). Orthotic musculoskeletal assessment can offer heel-lifts, a change of footwear, and custom-made orthoses which may correct malalignment.

Referral to a sports physician or an orthopaedic surgeon after 3–6 months is recommended if response to initial conservative measures and physiotherapy is inadequate.

Treatment options from specialists include:

Physical therapy treatments such as iontophoresis (topical introduction of ionized drugs into the skin using electrical current), phonophoresis (ultrasound-enhanced delivery of topical drugs), and low-level laser treatment.

Extracorporeal shock-wave therapy.

Sclerosant injections.

Glyceryl trinitrate patches.

Surgery to excise fibrotic adhesions, remove degenerated nodules, and create longitudinal incisions in the tendon to stimulate healing or decompress the tendon

Have I got the right topic?

144months3060monthsBoth

This CKS topic covers the diagnosis and management of Achilles tendinopathy (commonly referred to as Achilles tendinitis) and the recognition of Achilles tendon rupture.

This CKS topic does not cover, in any detail, the treatment in secondary care of Achilles tendinopathy or tendon rupture.

There is a separate CKS topic on Sprains and strains.

The target audience for this CKS topic is healthcare professionals working within the NHS in the UK, and providing first contact or primary health care.

How up-to-date is this topic?

How up-to-date is this topic?

Changes

Last revised in April 2010

January to April 2010 — this is a new CKS topic. The evidence-base has been reviewed in detail, and recommendations are clearly justified and transparently linked to the supporting evidence.

Update

New evidence

Evidence-based guidelines

Guidelines published since the last revision of this topic:

Chiodo, C.P., Glazebrook, M., Bluman, E.M., et al. (2010) Diagnosis and treatment of acute Achilles tendon rupture. Journal of the American Academy of Orthopaedic Surgeons 18(8), 503-513. [Abstract]

HTAs (Health Technology Assessments)

No new HTAs since 1 December 2009.

Economic appraisals

No new economic appraisals relevant to England since 1 December 2009.

Systematic reviews and meta-analyses

Systematic reviews published since the last revision of this topic:

Al-Abbad, H. and Simon, J.V. (2013) The effectiveness of extracorporeal shock wave therapy on chronic achilles tendinopathy: a systematic review. Foot and Ankle International 34(1), 33-41. [Abstract]

Coombes, B.K., Bisset, L., and Vicenzino, B. (2010) Efficacy and safety of corticosteroid injections and other injections for management of tendinopathy: a systematic review of randomised controlled trials. Lancet 376(9754), 1751-1767. [Abstract]

Habets, B. and van Cingel, R.E. (2014) Eccentric exercise training in chronic mid-portion achilles tendinopathy: a systematic review on different protocols. Scandinavian Journal of Medicine and Science in Sports epub ahead of print. [Abstract]

Holm, C., Kjaer, M. and Eliasson, P. (2014) Achilles tendon rupture - treatment and complications: a systematic review. Scandinavian Journal of Medicine and Science in Sports epub ahead of print. [Abstract]

Kearney, R., and Costa, M.L. (2010) Insertional achilles tendinopathy management: a systematic review. Foot & Ankle International 31(8), 689-694. [Abstract]

Khan, R.J.K., and Carey Smith, R.L. (2010) Surgical interventions for treating acute Achilles tendon ruptures (Cochrane Review). The Cochrane Library. Issue 9. John Wiley & Sons, Ltd. www.thecochranelibrary.com [Free Full-text]

Sadoghi, P., Rosso, C., Valderrabano, V., et al. (2013) The role of platelets in the treatment of Achilles tendon injuries. Journal of Orthopaedic Research 31(1), 111-118. [Abstract]

Sussmilch-Leitch, S.P., Collins, N.J., Bialocerkowski, A.E., et al. (2012) Physical therapies for achilles tendinopathy: systematic review and meta-analysis. Journal of Foot and Ankle Research 5(1), 15. [Abstract] [Free Full-text]

Wiegerinck, J.I., Kerkhoffs, G.M., van Sterkenburg, M.N., et al. (2013) Treatment for insertional Achilles tendinopathy: a systematic review. Knee Surgery, Sports Traumatology, Arthroscopy 21(6), 1345-1355. [Abstract]

Primary evidence

No new randomized controlled trials published in the major journals since 1 December 2009.

New policies

No new national policies or guidelines since 1 December 2009.

New safety alerts

No new safety alerts since 1 December 2009.

Changes in product availability

No changes in product availability since 1 December 2009.

Goals and outcome measures

Goals

To support primary healthcare professionals:

Make a diagnosis of Achilles tendinopathy

Manage people with Achilles tendinopathy appropriately in primary care

Appropriately refer people with Achilles tendinopathy to specialist

Recognize rupture of the Achilles tendon

Background information

Definition

What is it?

Achilles tendinopathy is a broad term used to describe predominantly degenerative conditions that cause pain, swelling, weakness, and stiffness of the Achilles tendon.

It is thought to result from repeated microtrauma which fails to heal.

Acute presentations are likely to be an exacerbation of this chronic underlying process.

The term 'Achilles tendinitis' is no longer preferred. Studies demonstrate that little or no prostaglandin-mediated inflammation is present in people with Achilles tendinopathy.

[Maffulli and Kader, 2002; Paavola et al, 2002; Andres and Murrell, 2008; Maffulli and Longo, 2008b]

Pathological processes

What are the pathological processes?

The Achilles tendon attaches the muscles in the lower leg (gastrocnemius, soleus, and when present, plantaris), to the heel bone (calcaneus). It measures 12–15 cm.

Repeated overloading of the tendon causes degeneration and disorganization of collagen fibres, increased cellularity, increased ground substance, and neovascularization.

Tendinopathy is thought to occur when there is an imbalance between the pathological changes and the regenerative changes that occur in response to injury. This in turn leads to degeneration, weakness, tearing, and pain.

There is little or no prostaglandin-mediated inflammation.

Tendinopathy most commonly occurs at the mid-portion of the tendon, 2–6 cm above the insertion into the calcaneus (non-insertional tendinopathy). It also occurs at the bone–tendon junction (insertional tendinopathy), and less frequently at the myotendinous junction.

A bursa located between the point of insertion at the calcaneus and the calcaneal tuberosity can also become inflamed and produce a retrocalcaneal bursitis.

[McLauchlan and Handoll, 2001; Maffulli and Kader, 2002; Bains and Porter, 2006; Alfredson and Cook, 2007; Andres and Murrell, 2008]

Causes

What causes it?

Causes of Achilles tendinopathy include:

Overuse, for example from running.

Biomechanical factors:

Intrinsic factors such as tibia vara (bowing of the leg at the knee), an overly pronated foot, tight or underdeveloped hamstrings, a high-arched (pes cavus) foot, and lateral instability of the ankle.

Extrinsic factors may include type of footwear, changes in training pattern, poor training technique, previous injuries, and environmental factors (such as training on hard, slippery, or slanting surfaces).

A number of factors are thought to contribute to the development of Achilles tendinopathy including:

Use of quinolone antibiotics.

Seronegative arthropathy (such as ankylosing spondylitis or psoriatic arthropathy).

Genetic predisposition (changes in expression of the genes regulating tendon healing have been found).

Tendon xanthomata (cholesterol deposits).

[Maffulli and Kader, 2002; Bains and Porter, 2006]

Prevalence

How common is it?

Achilles tendinopathy:

Has a lifetime cumulative incidence estimated to be 6% in inactive people.

Is one of the most common injuries in sport. The lifetime cumulative incidence has been estimated to be up to 50% in elite athletes.

Is very common in runners, and accounts for 6–17% of all running injuries.

Is predominantly a condition of men, particularly male athletes 30–40 years of age.

Achilles rupture:

Has an incidence that ranges from 6–18 ruptures per 100,000 people.

Is more common in men; complete rupture affects men three times more often than women.

[Paavola et al, 2002; Koike et al, 2004; Bains and Porter, 2006; American Academy of Orthopaedic Surgeons, 2009]

Prognosis

What is the prognosis?

The natural history of Achilles tendinopathy is unclear. The process of recovery tends to take months rather than weeks, particularly if excessive loading of the tendon continues.

Full recovery of symptoms does not ensure full recovery of muscle–tendon function. Continued rehabilitation is thought to improve the prognosis.

Achilles tendinopathy becomes more resistant to treatment if it is not recognized and managed at an early stage.

A study of people with Achilles tendinopathy reported that 94% were free of pain or had only mild pain on strenuous exercise when followed up 8 years after non-surgical treatment [Paavola et al, 2000b]. However, 40% had developed problems with their other Achilles tendon and 29% required surgery during this period.

Typically, up to a quarter of people with persisting symptoms require surgery.

Surgical success rates of over 70% are commonly reported [Maffulli and Kader, 2002].

[Koike et al, 2004; Silbernagel et al, 2007]

Complications

What are the complications?

The most common complications are a requirement for time off work and decreased participation in sports.

The risk of tendon rupture is generally low in people with painful Achilles tendinopathy.

Complications of surgery affect one in ten people. They are most commonly related to wound healing.

[Paavola et al, 2000a; American Academy of Orthopaedic Surgeons, 2009]

Diagnosis

Diagnosis of achilles tendinopathy

Diagnosis of Achilles tendinopathy

How do I know my patient has Achilles tendinopathy?

A diagnosis of Achilles tendinopathy is usually established on clinical grounds alone.

Ask about pain and stiffness in the tendon — its onset, relationship to activities, and aggravating factors.

Sudden onset of significant pain may indicate Achilles tendon rupture.

The pain of Achilles tendinopathy is usually located in the middle third of the tendon.

Pain and stiffness are worse first thing in the morning.

Pain may interfere with activities of daily living. It is usually felt after exercise but may also occur during exercise.

Runners tend to experience pain at the beginning and the end of training, with a period of diminished discomfort in between.

Look for swelling, deformity, and any signs of inflammation by exposing both legs from above the knees, and examining them whilst the person is standing and when prone.

Palpate for tenderness (usually located 2–6 cm proximal to the insertion at the heel), heat, crepitation, localized thickening, and nodularity in the tendon (more common in the chronic phase).

Exclude Achilles tendon rupture.

If the Achilles tendon is found to be intact, assess its function by asking the person to perform a tendon-loading activity.

In most people, simple single-leg heel raises will be sufficient to cause pain.

More active individuals may be asked to hop on the spot, or hop forward, in order to further load the tendon and reproduce pain.

Repetition of these loading tests may be necessary in some athletes to make a full evaluation.

Basis for recommendation

Basis for recommendation

These recommendations are based on review articles and expert opinion [Maffulli and Kader, 2002; Paavola et al, 2002; Alfredson and Cook, 2007].

Diagnosis of Achilles tendon rupture

How do I know my patient has a ruptured Achilles tendon?

Misdiagnosis, or delayed diagnosis of rupture of the Achilles tendon, is common; a fifth of ruptures are missed.

Suspect rupture of the Achilles tendon:

If the person reports:

An audible 'pop' and an impression of having been kicked in the calf.

Sudden onset of heel pain.

Difficulty walking.

If examination reveals:

Presence of a palpable gap (defect, loss of contour).

Weakness of ankle plantar flexion.

Reduced plantar flexion using the calf squeeze test.

Increased passive ankle dorsiflexion (Matles test) with gentle manipulation.

Look out for pitfalls.

It is possible that people with a completely torn tendon can walk into the surgery.

They may be able to plantar flex against resistance, courtesy of their other flexors.

No gap may be felt in the acute phase (due to haematoma) or in the chronic phase (due to organization).

The expected increase in passive dorsiflexion (Matles test) may be masked by pain.

Up to a third of people with complete tendon ruptures do not report pain after the acute pain of the rupture has subsided.

Chronic ruptures of the Achilles tendon are associated with considerable loss of function. A rupture becomes chronic 4–6 weeks after the original injury. Diagnosis may be difficult, because:

Pain and swelling have often subsided and the gap has filled with fibrous tissue.

The calf squeeze test may yield a false result (Matles test may be more accurate).

Push-off may be weak; calf muscles may be wasted.

Other muscles may facilitate plantar flexion (and also produce clawing of the toes).

Tests for rupture of the Achilles tendon

Tests for rupture of the Achilles tendon

The calf squeeze test, also known as the Thompson test or Simmonds squeeze test.

The person lies prone on the examination table with both feet over the edge.

The calf is squeezed just distal to its thickest part.

If the Achilles tendon is intact, the foot will plantar flex (a positive Thompson sign).

When the tendon is torn, the foot will not plantar flex as much as it does on the normal side.

Flexion may still occur due to an intact plantaris but there will be no toe-raise on the affected side.

The Matles test

The person lies prone.

The knees are flexed to 90 degrees.

Gravity makes the ankle on the ruptured side assume a more dorsiflexed position as compared with the normal side.

Unlike the calf-squeeze, Matles test should be positive even in older ruptures.

Basis for recommendation

Basis for recommendation

These recommendations are based on a US guideline, a review article, and expert opinion [Gravlee et al, 2000; Alfredson and Cook, 2007; Maffulli and Ajis, 2008; American Academy of Orthopaedic Surgeons, 2009].

In the absence of reliable evidence, two or more specific tests for rupture are recommended.

Sensitivity and specificity of the calf squeeze test have been measured at 0.96 (95% CI 0.91 to 0.99) and 0.93 (95% CI 0.76 to 0.99), respectively. Sensitivity and specificity of the Matles test (increased passive ankle dorsiflexion) has been measured at 0.88 (95% CI 0.79 to 0.95) and 0.86 (95% CI 0.67 to 0.96), respectively. Sensitivity and specificity of palpation of a gap has been measured at 0.73 (95% CI 0.65 to 0.80) and 0.89 (95% CI 0.72 to 0.98), respectively.

Investigations

What investigations are useful to establish a diagnosis of Achilles tendinopathy?

Achilles tendinopathy is a clinical diagnosis; imaging is generally not recommended in primary care.

Plain soft-tissue radiography is not usually of value. It may identify associated or incidental abnormalities (such as avulsion or calcification in the tendon).

Ultrasonography with colour and power Doppler is most often performed in secondary care. It may confirm a clinical diagnosis and also identify hypo-echoic areas, which are likely to consist of degenerated tissue.

Magnetic resonance imaging (MRI) may be useful in secondary care to evaluate the various stages of chronic degeneration.

The results of both ultrasound and MRI should be interpreted with caution as findings may not correlate with symptoms.

Basis for recommendation

Basis for recommendation

These recommendations are based on review articles and expert opinion [Maffulli and Kader, 2002; Bains and Porter, 2006; Alfredson and Cook, 2007; Paoloni and Murrell, 2007].

A diagnosis of Achilles tendinopathy should be made on clinical grounds, because:

Asymptomatic tendon degeneration is relatively common.

Imaging-negative tendinopathy is relatively common.

Clinical outcomes are independent of findings on imaging.

Ultrasonography or magnetic resonance imaging (MRI) may be used to look for pathology within the tendon if the clinical diagnosis is not clear. Doppler is particularly useful to demonstrate blood flow (which is not detectable in normal tendons).

Differential diagnosis

What else might it be?

Other diagnoses which cause pain in and around the Achilles tendon include:

Achilles tendon rupture .

Retrocalcaneal bursitis (a pinch just in front of the distal tendon may reproduce bursa pain).

Dislocation of the peroneal or other plantar flexor tendons.

Posterior ankle impingement (causes pain on forced plantar flexion when jumping or kicking).

Ankle osteoarthritis.

Haglund's deformity (a posterolateral calcaneal prominence 'pump bump' which can inflame).

Os trigonum syndrome (a floating bone just behind the ankle joint).

Systemic inflammatory disease (consider this if there are bilateral or systemic signs).

Calcaneal apophysitis (Sever's disease of adolescents).

Calcaneal stress fracture.

Irritation or neuroma of the sural nerve or sacral root pain.

Basis for recommendation

Basis for recommendation

This information is based on narrative review articles and expert opinion [Barrie and Wilson, 2005; Alfredson and Cook, 2007].

Management

Management

Scenario: Management : covers the management of Achilles tendinopathy and Achilles tendon rupture.

Scenario: Management

Scenario: Management of achilles tendinopathy

144months3060monthsBoth

Primary care management

How should I treat Achilles tendinopathy in primary care?

Exclude Achilles tendon rupture.

Explain that the symptoms of Achilles tendinopathy normally take 3–6 months to resolve.

Identify and manage any underlying causes and contributory factors.

Discontinue quinolone antibiotics.

Recommend cold packs or ice after acute injury. See the CKS topic on Sprains and strains for more information.

Recommend simple analgesia (either paracetamol or ibuprofen) for pain relief.

Where possible, limit the use of nonsteroidal anti-inflammatory drugs to 7–14 days.

Advise about physical activity.

Recommend an initial period of rest or relative rest (stopping high impact activities, such as running) until the pain subsides.

Consider a daily programme of Achilles tendon stretching exercises and strength training.

Recommend restarting exercise when pain allows. Complete rest can be counterproductive if it is prolonged.

Consider referring the person for a biomechanical assessment (depending on local services).

Physiotherapy allows access to a more intensive exercise programme (such as eccentric training).

Orthotic musculoskeletal assessment can offer heel-lifts, a change of footwear, and custom-made orthoses which may correct malalignment.

Do not inject corticosteroids in or around the tendon.

Arrange a follow-up appointment in the next 2–4 weeks, depending on the severity of symptoms, the amount of time the person has to take off work, and the requirement for analgesia.

If symptoms persist for 3–6 months, consider referral to a sports physician (if available) or an orthopaedic specialist.

Basis for recommendations

Basis for recommendations

These recommendations are mainly based on information in review articles and on expert opinion [McLauchlan and Handoll, 2001; Maffulli and Kader, 2002; Paavola et al, 2002; Alfredson and Cook, 2007; Paoloni and Murrell, 2007; Andres and Murrell, 2008; Glaser et al, 2008; Maffulli and Longo, 2008b].

There is little evidence on which to base recommendations for the treatment of Achilles tendinopathy. Very few randomized, placebo-controlled trials have examined treatments for Achilles tendinopathy. The studies that have been undertaken are limited by small sample sizes, short follow up, poor methodological quality, and variable definitions of the condition. CKS identified no randomized trials comparing conservative management with surgical treatments.

Currently, there is no consensus of preference for one treatment over another. For such a common condition, this may indicate that no treatment is particularly effective in changing its natural history [McLauchlan and Handoll, 2001].

Fluoroquinolones

The Committee on Human Medicines (formerly the Committee on Safety of Medicines) [MHRA, 2002] advises that:

If tendinitis is suspected, quinolones (for example ciprofloxacin, ofloxacin) must be stopped immediately.

Fluoroquinolones are contraindicated where there is a history of tendon disorders related to their use.

Current exposure to fluoroquinolones increases the risk of Achilles tendon disorders. However, it is relatively rare and, from the best available evidence, seems to be restricted to people older than 60 years of age. The risk increases very substantially if corticosteroids are also being taken. The mechanism is unknown but the onset can be very sudden (occasionally after a single dose of quinolone) which suggests a direct toxic effect on collagen [van der Linden et al, 2002].

Conservative treatment

A conservative approach to the initial management of Achilles tendinopathy is recommended by most experts, although the efficacy of this approach is uncertain. Achilles tendinopathy is difficult to treat and teaching control of symptoms may be more beneficial than encouraging the expectation of a total cure. Explanation aims to reduce the chance of a premature return to sport and avoid failure of treatment [Khan et al, 2002].

Cold packs may control inflammation in the early phase of an injury. Cold therapy helps control pain and oedema and prevent further tissue damage at the site of the injury [Paavola et al, 2002].

Stretching and strength exercises are widely recommended by experts and may be effective for pain control, restoring flexibility, and preventing disuse atrophy [Koike et al, 2004].

Orthotics

Orthotics aim to alter the biomechanics of the foot and ankle. Foot posture has not been clearly linked to Achilles tendinopathy [Alfredson and Cook, 2007]. However, orthotics are commonly used and some claim high rates of success in people with Achilles tendinopathy.

A heel lift of 12–15 mm is commonly used to help relieve pain; however, there have been no studies of the efficacy of this simple measure [Maffulli and Kader, 2002].

Simple analgesia

Paracetamol has a similar analgesic effect to nonsteroidal anti-inflammatory drugs (NSAIDs) with a better risk profile; it is often recommended first-line in acute and chronic musculoskeletal pain [Paoloni et al, 2009]. When using NSAIDs, a considered decision should be made on whether they are being used for analgesic, anti-inflammatory, or combined effects. Presentations in primary care may be more acute and treating suspected inflammation with an NSAID may well be reasonable in these circumstances [Paoloni et al, 2009].

In the absence of an overt inflammatory process, expert opinion and the available literature suggests that there is no rational basis for the use of NSAIDs in chronic tendinopathy [Magra and Maffulli, 2006]. NSAIDs may have a negative effect on long-term healing. They may allow people to ignore early symptoms — which may delay healing [Magra and Maffulli, 2006]. NSAIDs do not provide long-term benefit, and their longer-term use is not supported by evidence.

Corticosteroids

Corticosteroid injections (CSIs) are widely used in the treatment of tendinopathies. However, there is controversy as to their usefulness and safety in the treatment of Achilles tendinopathy. The evidence for their ability to relieve pain in the short term (up to 6 weeks) relates predominantly to areas other than the Achilles tendon (for example the shoulder) and cannot be clearly extrapolated [Andres and Murrell, 2008].

Intratendinous CSIs are contraindicated due to the risk of further damaging the tendon [Alfredson and Cook, 2007].

A literature search identified 19 controlled trials and systematic reviews of CSI in the treatment of tendinopathy; the conclusion was that the findings were mixed. In particular, there were several cases of Achilles tendon rupture following CSI [Andres and Murrell, 2008].

Peritendinous CSI is controversial and currently there is no good scientific evidence to support it [Maffulli and Kader, 2002]. A Cochrane systematic review in 2001 (and not updated subsequently) found that there was no clear advantage of peritendinous steroid injection, but this could not be fully evaluated from the limited trials [McLauchlan and Handoll, 2001]. Peritendinous injection has less of an effect on the tendon than intratendinous injection and some experts may use it as part of a management plan, perhaps in relieving pain while continuing to undertake exercise regimens [Alfredson and Cook, 2007]. It may be best performed under imaging techniques [Andres and Murrell, 2008].

Some experts inject steroids into the retrocalcaneal bursa if the problem is well-localized there [Barrie and Wilson, 2005].

Physiotherapy

The best evidence demonstrates that eccentric exercise is a useful management strategy for tendinopathy, but the evidence is currently insufficient to confirm that it is better or worse than other forms of therapeutic exercise [Maffulli and Longo, 2008a].

Suspected Achilles rupture

How should I manage suspected Achilles rupture?

If acute Achilles tendon rupture is suspected, refer the person immediately to the Accident and Emergency department.

Treatment options include conservative measures or operative management.

If chronic rupture is suspected, refer the person to the Accident and Emergency department, or the next available outpatient clinic (as appropriate).

Operative management is generally offered.

Basis for recommendation

Basis for recommendation

Referral recommendations

The recommendations for referral are based on good clinical practice.

Management in secondary care

The treatment of acute Achilles tendon rupture is controversial. Opinions differ on when to opt for operative or non-operative treatment. Expert consensus states that surgery should be used more cautiously in people with diabetes, neuropathy, or immunocompromise, and in those older than 65 years of age, or who smoke, have a sedentary lifestyle, or have obesity, or peripheral vascular disease or local/systemic dermatological disorders [American Academy of Orthopaedic Surgeons, 2009]. Chronic ruptures are likely to require operative management [Maffulli and Ajis, 2008].

Eccentric exercise training

What is eccentric exercise training?

Eccentric loading involves lengthening the muscle fibres as contraction occurs. It is thought to reduce tendon thickness, promote formation of collagen and restore normal architecture.

An eccentric exercise programme is frequently preferred to concentric training (calf raises) for rehabilitation of chronic Achilles tendinopathy. A typical eccentric training protocol:

The person starts by standing on one leg, on tip-toes.

The Achilles tendon is then eccentrically loaded by slowly lowering the heel to a dorsiflexed position.

The person returns to the starting position, using their arms or contralateral leg for assistance to avoid concentric loading of the involved Achilles tendon.

Alfredson's model of eccentric calf-muscle training (painful heel-drops) is a popular type of eccentric training.

It involves heavy loading of the tendon in the acute phase of tendinopathy (but no concentric loading).

A programme lasting 12 weeks is recommended when other conventional treatments have failed. If there is a response, exercise is continued for 6–12 months.

Loading is increased until the exercises provoke pain.

The protocol is completed despite pain in the tendon.

Activities such as running may continue during the programme.

Basis for recommendation

Basis for recommendation

The information about eccentric exercise is based on narrative reviews and expert opinion [Maffulli and Kader, 2002; Barrie and Wilson, 2005; Alfredson and Cook, 2007; Andres and Murrell, 2008; Glaser et al, 2008]. The best evidence demonstrates that eccentric exercise is a useful management strategy for tendinopathy, but the evidence is currently insufficient to confirm that it is better or worse than other forms of therapeutic exercise [Maffulli and Longo, 2008a].

Physiotherapy treatments

What treatment can a physiotherapist offer?

Physiotherapy techniques are commonly used for the treatment of tendinopathies.

There is a wide variety of available interventions. Physiotherapists commonly offer stretching and strengthening programmes which benefit the calf muscle complex.

Eccentric exercise training is widely used. Expert supervision by a physiotherapist may be of great value in some people.

The therapy offered may vary from one physiotherapist to the next:

The efficacy of massage, including deep transverse friction massage, has not been clearly proven; however, it may reduce pain in some people.

Therapeutic ultrasound may improve healing (but evidence for this is currently lacking).

Hyperthermia with low-frequency microwave may be effective for decreasing pain.

Acupuncture is sometimes used (but there is no evidence on its use in Achilles tendinopathy).

Night splints may be used.

Basis for recommendation

Basis for recommendation

This information about physiotherapy treatments for Achilles tendinopathy is based on expert review articles [Brosseau et al, 2002; Maffulli and Kader, 2002; Alfredson and Cook, 2007; Andres and Murrell, 2008].

There is little consensus as to which physical treatment should be used.

Night splints are often considered to be an effective intervention for Achilles tendinopathy. However a single-blind, prospective randomized controlled trial in 70 tendons found that a night splint was of no added value when used in addition to a 12-week eccentric training programme for the treatment of chronic Achilles tendinopathy [Alfredson and Cook, 2007; de Vos et al, 2007].

Follow-up

How should I follow up someone with Achilles tendinopathy?

Exclude an Achilles tendon rupture which has become chronic.

Reassess symptoms and functional ability.

Advise on physical activity.

The person should avoid too much training too soon.

The person should consider stretching exercises before sporting activities. A leaflet with illustrated details of exercises is available (see www.arc.uk (pdf)).

Refer the person to a physiotherapist if initial conservative measures are failing.

The physiotherapist should have the appropriate skills to choose the most appropriate treatment options (such as eccentric training), and instigate further investigation and treatment as needed.

Consider biomechanical assessment (where available; for example, from a specialized orthotic musculoskeletal assessment unit). Modification of foot posture or orthotic devices may be offered.

If symptoms are improving, advise the person to continue strengthening exercises, long term, to aid recovery and prevent recurrence.

If symptoms persist for 3–6 months, refer the person to a sports physician or orthopaedic surgeon (depending on availability).

Stretching exercises

Stretching exercises

Achilles tendon and plantar fascia stretch

Advise the person to keep a long towel (or length of tubigrip) beside their bed. Before they get out of bed, they should loop the towel around their foot, and pull it with the knees straight, causing dorsiflexion.

This should be held for 30 seconds and repeated three times for each foot.

Recommend the use of a duvet in bed (as opposed to tucked-in sheets).

Wall push-ups or stretches for the Achilles tendon

In order to stretch both parts of the Achilles tendon, these exercises need to be performed first with the knee straight and then with the knee bent.

Advise the person to face the wall, and put both hands on the wall at shoulder height, staggering the feet (one foot in front of the other).

The front foot should be approximately 30 cm (12 inches) from the wall. With the front knee bent and the back knee straight, the person should lean towards the wall, until a tightening is felt in the calf of the back leg, and then ease off. This is repeated ten times.

Then, repeat again, this time with the back foot forward a little so that the back knee is slightly bent. This is repeated ten times.

These exercises should be performed twice daily.

Stair stretches for the Achilles tendon and plantar fascia

Advise the person to stand on the bottom step of the stairs, facing upstairs, using the stair-rail for support.

The feet should be positioned so that both heels are off the end of the step, with the legs slightly apart. The heels are lowered, keeping the knees straight, until a tightening is felt in the calf. The position is held for 20–60 seconds, and then the heels are raised back to neutral.

The process should be repeated six times, at least twice a day.

Chair stretches for the Achilles tendon and plantar fascia

Advise the person to sit in a chair with their knees bent at right angles and their feet and heels flat on the floor. Then they should lift the foot upwards with the heel kept on the floor (the calf muscles and Achilles tendon should be felt to tighten).

The position should be held for several seconds, then relaxed.

This process can be repeated about ten times in a session, and the whole routine repeated five or six times a day.

Basis for recommendation

Basis for recommendation

The recommendations for stretching and strengthening exercises for Achilles tendinopathy are based on expert opinion. Strength and flexibility decrease with age, and measures to prevent this are likely to be helpful [Alfredson and Lorentzon, 2000]. Specific practical guidance is based on information from Arthritis Research UK (available at www.arthritisresearchuk.org (pdf)) [ARC, 2004]. The recommendation to continue doing exercises is based on expert opinion [Silbernagel et al, 2007].

Referral

When should I refer a person with Achilles tendinopathy to secondary care?

Refer the person promptly to the Accident and Emergency department for orthopaedic opinion if Achilles tendon rupture is suspected.

This includes partial rupture (which would not usually require surgery, but may require splinting or protected mobilization).

Refer the person to a sports physician or an orthopaedic surgeon (depending on local availability) if, after 3–6 months, response to initial conservative measures and physiotherapy is inadequate.

The exact timing of referral should be individually tailored to the person. Important factors to consider include:

Inability to fully bear weight.

Inability to complete an exercise-based programme (for example elderly people).

Difficulty getting shoes on (such as occurs with insertional tendinopathy).

The requirements of the elite athlete.

Basis for recommendation

Basis for recommendation

These recommendations on expert review articles and expert opinion [Koike et al, 2004; Barrie and Wilson, 2005; Alfredson and Cook, 2007; Glaser et al, 2008; Maffulli and Longo, 2008b].

Most experts advise a trial of conservative therapy for around 6 months before resorting to surgery for Achilles tendinopathy.

Treatments in secondary care

What treatments are available in secondary care for Achilles tendinopathy?

Non-surgical intervention may involve a number of new treatments that have not yet been fully evaluated but are undertaken by some experts. Some of these may not be widely available.

Physical therapy treatments such as iontophoresis (topical introduction of ionized drugs into the skin using electrical current), phonophoresis (ultrasound-enhanced delivery of topical drugs), and low-level laser treatment lack sufficient evidence of their efficacy at this time.

Extracorporeal shock-wave therapy passes acoustic shock waves through the skin to the affected area. Ultrasound may be used to facilitate localization and local anaesthesia may relieve the pain of higher-energy shock-wave therapy. Skin reddening and calf ache are common adverse effects and tendon rupture is a concern, particularly in older people. The National Institute for Health and Care Excellence advises that specialists use this therapy only with close monitoring and clinical governance.

Sclerosant that is injected into areas of neovascularisation probably destroys associated pain-generating fibres.

Many drugs have been tried, with no conclusive evidence of effectiveness. High volume injections, and injections of platelet-derived growth factors, are sometimes used. Future possibilities include growth factors and/or stem cells; these may reverse the degenerative process and stimulate regeneration of the tendon.

Glyceryl trinitrate patch may be prescribed in addition to an exercise programme.

Surgery

Up to 25% of people with persistently painful Achilles tendinopathy require surgery.

Surgical interventions include excision of fibrotic adhesions, removal of degenerated nodules, and longitudinal incisions in the tendon to stimulate healing or decompress the tendon.

Pain is relieved by surgery in most people.

Surgery is more effective in athletes. Recovery is faster and they experience fewer complications.

Potential complications include skin edge necrosis, wound infection, seroma or haematoma formation, fibrotic reaction and scarring, and new partial rupture.

Basis for recommendation

Basis for recommendation

Shock wave therapy

The evidence for extracorporeal shock wave therapy (ESWT) is limited and it remains a controversial option in Achilles tendinopathy. The ideal choice of energy setting and method of application is unknown. In addition, the mechanism of any potential benefit for tendinopathy (in terms of pain relief or healing) is not clear.

The National Institute for Health and Care Excellence (NICE) intervention procedure guidance found that results of studies were conflicting and there was evidence of a substantial placebo response. NICE advises that ESWT should be used for refractory Achilles tendinopathy only by special arrangement with clinical governance, consent, and audit; or research. People receiving this treatment should fully understand the uncertainty regarding efficacy and the possible risk of tendon rupture [NICE, 2009].

Sclerotherapy

Information on sclerotherapy is based on reviews of small studies which have shown early promise in expert hands. There may be a role for sclerotherapy in those people who do not respond to eccentric exercise. Colour Doppler ultrasound is used to guide the injection, and the potential worry of causing further damage to the Achilles tendon appears to be unsubstantiated; complication rates are low [Alfredson and Cook, 2007; Andres and Murrell, 2008].

A double-blind randomized controlled trial (RCT) compared the effects of injections of a sclerosant (polidocanol) and a non-sclerosing substance (lidocaine with adrenaline) in 20 consecutive people with chronic mid-portion Achilles tendinopathy. The trial found that the sclerosing substance was clearly effective and levels of recipient satisfaction were very high. Data from other investigators are required [Alfredson and Ohberg, 2005; Andres and Murrell, 2008].

Glyceryl trinitrate

Nitric oxide may play a role in tendon healing after injury. It has been suggested that the addition of exogenous nitric oxide to an area of tendon damage may promote healing (as opposed to just analgesia).

Information on the use of topical glyceryl trinitrate (GTN) is based on expert opinion, the opinion of CKS expert reviewers, and on evidence from one RCT [Alfredson and Cook, 2007; Andres and Murrell, 2008].

The use of GTN patches appears to be a suitable next step when early conservative measures fail, although opinion differs as to their value. Furthermore, adverse effects (such as skin reaction and headaches) are common. Larger multicentre studies are needed to validate the efficacy and safety of GTN patches.

Other non-surgical interventions

Expert review articles discuss a number of plausible treatments which have been tried or are in development. However, there is a lack of adequately powered studies to demonstrate effectiveness [Koike et al, 2004; Alfredson and Cook, 2007; Andres and Murrell, 2008].

Surgery

Information about surgical treatment of chronically painful Achilles tendinopathy is based on review articles [Paavola et al, 2000a; Maffulli and Kader, 2002; Alfredson and Cook, 2007; Glaser et al, 2008].

A systematic review of 26 studies, of people managed surgically, found a full return to pre-injury activity level in 77%. Studies reporting higher success rates had poorer methodology scores; this may explain why such results are not always seen in practice [Tallon et al, 2001].

Various surgical interventions are used but there is no consensus as to the best approach. Almost all published studies of surgical treatments for Achilles tendinopathy are retrospective in nature and lack control groups [Andres and Murrell, 2008].

Important aspects of prescribing information relevant to primary healthcare are covered in this section specifically for the drugs recommended in this CKS topic. For further information on contraindications, cautions, drug interactions, and adverse effects, see the electronic Medicines Compendium (eMC) (http://medicines.org.uk/emc), or the British National Formulary (BNF) (www.bnf.org).

Ibuprofen

Ibuprofen

Do not use ibuprofen in:

People with a history of hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) — for example bronchospasm, asthma, rhinitis, or urticaria known to have been precipitated by an NSAID.

People with peptic ulcers or who are at high risk of gastrointestinal bleeding or ulceration.

People taking ciclosporin, lithium, methotrexate, or other NSAIDs.

If possible, avoid NSAIDs in:

People with hypertension, heart failure, or renal impairment. NSAIDs can worsen or precipitate these conditions.

Women who are pregnant (ibuprofen should not be used from 30 weeks of pregnancy onwards).

People taking antihypertensives, digoxin, oral corticosteroids, or warfarin.

For a detailed discussion on the contraindications, adverse effects, monitoring issues, and interactions of NSAIDs, see the CKS topic on NSAIDs - prescribing issues.

Pregnancy and breastfeeding

Pregnancy and breastfeeding

Paracetamol is the analgesic of choice during pregnancy and breastfeeding.

If paracetamol is ineffective, ibuprofen is an alternative during the first or second trimester, but should not be used from 30 weeks of pregnancy onwards (off-label use).

Ibuprofen can also be used during breast feeding because its half-life is short, and levels in breast milk are negligible.

For a detailed discussion on the safety of using NSAIDs during pregnancy and breastfeeding, see the CKS topic on NSAIDs - prescribing issues.

Evidence

Evidence

Supporting evidence

There is a lack of good quality evidence on which to base recommendations for the management of Achilles tendinopathy in primary care. Most recommendations are therefore based on expert opinion. The evidence on an association between fluoroquinolones and Achilles tendinopathy and the use of nonsteroidal anti-inflammatory drugs has been reviewed and summarized in this section. The evidence on secondary care interventions for Achilles tendinopathy and rupture has not been reviewed (with the exception of glycerol trinitrate patches).

Quinolones

Evidence on the association between quinolones and Achilles tendinopathy

Evidence from a case-controlled study in a large UK-based general practice supports an association between quinolone use and Achilles tendon disorders.

The use of fluoroquinolones was stratified: current use (within 30 days of starting antibiotic), recent use (within the last 30–90 days), past use (more than 90 days ago), and no use [van der Linden et al, 2002]. The cohort included 704 people with Achilles tendinitis and 38 with Achilles tendon rupture.

Relative risk of Achilles tendon disorders with current use of fluoroquinolones:

Overall, was 1.9 (95% CI 1.3 to 2.6).

Among people older than 60 years of age, was 3.2 (95% CI 2.1 to 4.9).

Among people younger than 60 years of age, was 0.9 (95% CI 0.5 to 1.6).

In people 60 years of age or older, concurrent use of corticosteroids and fluoroquinolones increased the risk to 6.2 (95% CI 3.0 to 12.8).

In this study, the proportion of Achilles tendon disorders attributable to this interaction was 87%.

NSAIDs

Evidence on NSAIDs in the treatment of Achilles tendinopathy

Weak evidence supports the effectiveness of nonsteroidal anti-inflammatory drugs (NSAIDS) for Achilles tendinopathy; there is no evidence of any long-term benefit.

A Cochrane systematic review, conducted in 2001 [McLauchlan and Handoll, 2001], identified just nine randomized trials of treatments for acute and chronic Achilles tendinitis in adults. The trials included 697 people in two categories; young adult male army personnel, and older mostly male adults who were mainly competitive or recreational athletes.

The definition of Achilles tendinitis varied. Eight trials defined it in different ways, and one trial did not provide a definition. One study specified that it included insertional tendonitis and one study specifically excluded this. Just two studies investigated a non-pharmaceutical intervention and no trials investigated the effectiveness of surgery.

The evidence was not robust. From three relevant trials, there was weak evidence that NSAIDs had a modest effect (at best) in relieving acute symptoms in the short term (10–21 days). The trials included topical and oral NSAIDs. Studies were of poor methodology, had inadequate outcome measures, lacked intent-to-treat analysis, and used an inappropriately short duration of follow up.

An extensive literature review identified 37 randomized clinical trials and systematic reviews evaluating NSAIDs for the treatment of tendinopathy. These data largely did not refer to Achilles tendinopathy and only 17 of 37 trials were placebo-controlled. Only three of these showed improvement with NSAIDs. Those participants with prolonged symptoms had a poorer response. There was no evidence of benefit in Achilles tendinopathy and the authors noted that NSAIDs may be less effective in Achilles tendinopathy than in tendinitis elsewhere in the body. However, as evidence is still limited, the authors advise a short course of NSAIDs may be a reasonable option for the treatment of acute pain due to Achilles tendinitis in the first 14 days [Andres and Murrell, 2008].

Nitrates

Evidence on nitrates in the treatment of Achilles tendinopathy

Evidence from a single high-quality trial suggests that glyceryl trinitrate (GTN) patches are effective in the treatment of Achilles tendinopathy.

One randomized, placebo-controlled, double-blind clinical study examined the use of GTN patches for the treatment of Achilles tendinopathy [Paoloni and Murrell, 2007]. The subject is further discussed in a review article [Andres and Murrell, 2008].

Typical treatment was at least GTN 1.25 mg every 24 hours (a 5 mg patch cut into quarters) compared with placebo. Every day, the patch was placed over the point of maximum tenderness; it was worn until the symptoms subsided or the study ended (6 months). The participants were followed up for 3 years.

After 6 months, 78% of the treatment group were asymptomatic and undertaking activities of daily living, compared with 49% for placebo.

At 3 years there was sustained long-term benefit, with less tenderness and improved pain scores.

A total of 88% of people in the GTN group were completely asymptomatic compared with 67% for placebo.

The most common adverse effect was headache, which was sometimes severe enough to cause cessation of treatment.

In well-controlled study populations, GTN patches appear to be effective with minimal morbidity.

Search strategy

Scope of search

A literature search was conducted for guidelines, systematic reviews and randomized controlled trials on primary care management of Achilles Tendinopathy, with additional searches for evidence in the following areas:

Nonsteroidal anti-inflammatory agents

Corticosteroids

Search dates

January 1990 – December 2009

Key search terms

Various combinations of searches were carried out. The terms listed below are the core search terms that were used for Medline.

Achilles Tendon/, Tendinopathy/, achilles tendinitis.tw., paratendinitis.tw., tendinopathy.tw.

corticosteroid injection$.tw., Anti-Inflammatory Agents, Non-Steroidal/, NSAID.tw., non-steroidal anti-inflammatory agents.tw.

Table 1 . Key to search terms.
Search commands Explanation
/ indicates a MeSh subject heading with all subheadings selected
.tw indicates a search for a term in the title or abstract
exp indicates that the MeSH subject heading was exploded to include the narrower, more specific terms beneath it in the MeSH tree
$ indicates that the search term was truncated (e.g. wart$ searches for wart and warts)
Sources of guidelines

National Institute for Health and Care Excellence (NICE)

Scottish Intercollegiate Guidelines Network (SIGN)

National Guidelines Clearinghouse

New Zealand Guidelines Group

British Columbia Medical Association

Canadian Medical Association

Institute for Clinical Systems Improvement

Guidelines International Network

National Library of Guidelines

National Health and Medical Research Council (Australia)

Alberta Medical Association

University of Michigan Medical School

Michigan Quality Improvement Consortium

Royal College of Nursing

Singapore Ministry of Health

Health Protection Agency

National Resource for Infection Control

CREST

World Health Organization

NHS Scotland National Patient Pathways

Agency for Healthcare Research and Quality

TRIP database

Patient UK Guideline links

UK Ambulance Service Clinical Practice Guidelines

RefHELP NHS Lothian Referral Guidelines

Medline (with guideline filter)

Sources of systematic reviews and meta-analyses

The Cochrane Library :

Systematic reviews

Protocols

Database of Abstracts of Reviews of Effects

Medline (with systematic review filter)

EMBASE (with systematic review filter)

Sources of health technology assessments and economic appraisals

NIHR Health Technology Assessment programme

The Cochrane Library :

NHS Economic Evaluations

Health Technology Assessments

Canadian Agency for Drugs and Technologies in Health

International Network of Agencies for Health Technology Assessment

Sources of randomized controlled trials

The Cochrane Library :

Central Register of Controlled Trials

Medline (with randomized controlled trial filter)

EMBASE (with randomized controlled trial filter)

Sources of evidence based reviews and evidence summaries

Bandolier

Drug & Therapeutics Bulletin

MeReC

NPCi

BMJ Clinical Evidence

DynaMed

TRIP database

Central Services Agency COMPASS Therapeutic Notes

Sources of national policy

Department of Health

Health Management Information Consortium (HMIC)

References

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Alfredson, H. and Ohberg, L. (2005) Sclerosing injections to areas of neo-vascularisation reduce pain in chronic Achilles tendinopathy: a double-blind randomised controlled trial. Knee Surgery, Sports Traumatology, Arthroscopy 13(4), 338-344. [Abstract]

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