Achilles Tendon Rupture
Lower LimbOverview
Achilles tendon rupture is a complete or partial tear of the largest tendon in the body, typically occurring during sudden plantarflexion or dorsiflexion movements. This condition presents with acute pain, loss of plantarflexion strength, and functional impairment requiring urgent medical evaluation. Rupture may be traumatic or degenerative, with the latter occurring in previously weakened tendons.
Pathophysiology
The Achilles tendon, formed by the gastrocnemius and soleus muscles, experiences greatest tensile stress during push-off activities and rapid directional changes. Rupture typically occurs in the watershed zone 2-6cm above the calcaneal insertion, where blood supply is poorest. The mechanism involves either acute traumatic overload or chronic degenerative changes with microruptures that eventually fail under normal stress.
Patient Education
An Achilles tendon rupture requires immediate medical imaging and specialist assessment, as surgical repair within 48-72 hours significantly improves functional outcomes compared to delayed treatment.
Typical Presentation
Site
Posterior ankle and lower calf, typically 2-6cm above the heel insertion; may be bilateral in inflammatory conditions
Quality
Acute sharp or tearing sensation at moment of injury; subsequent throbbing, aching pain with swelling
Intensity
Severe acute pain (often 8-10/10) at onset; may diminish with rest; functional inability to plantarflex or walk normally
Aggravating
Weight-bearing, walking, running, jumping, plantarflexion against resistance, active dorsiflexion of ankle, climbing stairs
Relieving
Rest, elevation, ice application, non-weight-bearing positioning, anti-inflammatory medication
Associated
Swelling and bruising in calf and ankle, visible gap or indentation at rupture site, positive Thompson test (no plantarflexion with calf squeeze), inability to stand on tiptoes, audible pop or crack at moment of injury, immediate functional loss
Orthopaedic Tests
Test descriptions are written with AI assistance from standard clinical texts. Where a test lists Sources, its description has been checked against them; those sources are independent and do not endorse OsteoKit. Accuracy figures and grades (A–D) appear only when checked against the published study; tests without one are marked “No accuracy study”.
Further reading: full test procedures are described in standard clinical examination texts, e.g. Magee & Manske, Orthopedic Physical Assessment (7th ed.), and Cook & Hegedus, Orthopedic Physical Examination Tests: An Evidence-Based Approach (2nd ed.).
Thompson Test (Simmonds Test)
Procedure
Patient prone with the feet over the end of the plinth, or kneeling on a chair. Squeeze the calf muscle firmly and watch the foot. Compare with the other leg.
Positive Finding
No plantarflexion (or clearly less than on the other side) when the calf is squeezed.
Sensitivity / Specificity
Reference: Maffulli N. The clinical diagnosis of subcutaneous tear of the Achilles tendon. A prospective study in 174 patients. Am J Sports Med. 1998;26(2):266-70.
Interpretation
A positive test strongly supports a complete Achilles rupture and needs same-day referral. Some plantarflexion can still occur through intact plantaris or other tendons, so compare sides and combine it with the Matles test and palpation. From 174 patients with an Achilles tendon rupture and 28 patients who were suspected of a rupture but did not have one on imaging (Maffulli 1998). The comparison group is small, so the specificity is less precise than the sensitivity. In the same study, at least two tests were positive in every patient with a rupture.
Palpable Gap Test
Procedure
Patient prone. Run your fingers gently down the tendon from the calf to the heel, feeling for a gap, usually 2–6 cm above the heel.
Positive Finding
A palpable gap or dip in the tendon.
Sensitivity / Specificity
Reference: Maffulli N. The clinical diagnosis of subcutaneous tear of the Achilles tendon. A prospective study in 174 patients. Am J Sports Med. 1998;26(2):266-70.
Interpretation
A gap strongly supports a rupture, but swelling and bruising can fill it, so it is often missed early. A negative result does not exclude a rupture. From 174 patients with an Achilles tendon rupture and 28 patients who were suspected of a rupture but did not have one on imaging (Maffulli 1998). The comparison group is small, so the specificity is less precise than the sensitivity. In the same study, at least two tests were positive in every patient with a rupture. A gap can be hidden by swelling and haematoma, which explains the lower sensitivity.
Calf Raise Test (Single-Leg Heel Raise)
Procedure
Ask the patient to stand on the affected leg and rise onto the toes.
Positive Finding
Unable to rise onto the toes on the affected leg.
Interpretation
Inability supports a rupture, but many people with a complete rupture can still plantarflex using the toe flexors and peroneals, and some can rise weakly. Do not rely on it to exclude a rupture. A literature search (Europe PMC, September 2026) found no study reporting the diagnostic accuracy of this test, so no figure is shown. Many patients with a complete rupture can still plantarflex using other muscles.
Plantarflexion Strength Test
Procedure
Patient seated or prone. Ask the patient to push the foot down against your resistance and compare with the other side.
Positive Finding
Clearly weaker plantarflexion than on the other side.
Interpretation
Weakness supports a rupture, but strength can be surprisingly preserved because the long toe flexors, tibialis posterior and peroneals still plantarflex. A strong-seeming push does not exclude a rupture. A literature search (Europe PMC, September 2026) found no study reporting the diagnostic accuracy of this test, so no figure is shown. Plantarflexion strength can be preserved after a complete rupture because the long toe flexors and peroneals still work.
Ankle Dorsiflexion Passive Range of Motion Increase
Procedure
Patient prone. Gently dorsiflex each ankle and compare the range, or compare the resting angle of both feet with the knees bent (Matles test).
Positive Finding
More passive dorsiflexion, or a more dorsiflexed resting position, on the injured side.
Interpretation
Loss of the normal resting tension of the tendon supports a rupture. Do not force dorsiflexion if a rupture is suspected.
Ultrasound or MRI Imaging Assessment
Procedure
Arranged by the treating doctor when the clinical tests are unclear or for treatment planning: ultrasound (often the first choice) or MRI.
Positive Finding
A gap between the torn tendon ends, with fluid or haematoma.
Interpretation
Confirms the rupture and measures the gap, which can influence the choice between non-operative and operative treatment. When the clinical tests are clearly positive, imaging is not always needed before referral.
Sources
- Reference bookShamrock AG, Dreyer MA, Varacallo MA. Achilles Tendon Rupture. StatPearls [Internet]. StatPearls Publishing; updated 17 Aug 2023.
- RelatedHabets et al., 2012, Cochrane Database; Cetti et al., 1995, American Journal of Sports Medicine
⚠ Red Flags
- •Acute traumatic injury with severe pain, swelling, and functional loss requiring immediate imaging
- •Complete loss of plantarflexion strength on manual testing
- •Visible gap or deformity in tendon region
- •Signs of compartment syndrome: severe swelling, pain disproportionate to injury, paresthesias
- •Bilateral ruptures suggesting systemic inflammatory disease or metabolic condition
- •Skin breakdown or signs of infection overlying rupture site
- •Neurovascular compromise: absent pulses, cold foot, severe paresthesias
⚡ Yellow Flags
- •Fear-avoidance behaviors limiting rehabilitation engagement post-injury
- •Unrealistic expectations about recovery timeline and return to sport
- •Previous tendon injuries or chronic pain conditions affecting psychosocial resilience
- •Occupational or sporting demands incompatible with conservative management
- •Low mood or depression affecting motivation for structured rehabilitation
- •Catastrophizing about functional loss or permanent disability
Osteopathic Techniques
Refer first
A ruptured Achilles tendon needs an orthopaedic decision between surgery and non-operative care. Early care is rest, elevation, pain control and functional bracing; with modern rehabilitation both routes give good results, and both need structured physiotherapy. Refer before using manual techniques on the calf or tendon.
- Reference bookShamrock et al. · StatPearls 2023
Rehabilitation Exercises
Ankle Alphabet - Toe Writing
Seated Ankle Dorsiflexion and Plantarflexion
Supine Hip and Knee Flexion with Ankle Pumps
Seated Calf Stretch with Towel
Wall Quad and Hip Flexor Stretch
Isometric Plantarflexion - Seated
Isometric Dorsiflexion - Seated
Standing Calf Raises - Double Leg
Standing Calf Raises - Single Leg
Double Leg Stance on Firm Surface
Single Leg Stance on Firm Surface
Single Leg Stance on Balance Pad or Foam
Referral Criteria
- •Acute presentation with severe pain, swelling, and loss of function - urgent referral to emergency department for imaging and orthopedic assessment
- •Suspected complete rupture based on positive Thompson test and functional loss - immediate orthopedic consultation for consideration of surgical repair
- •Post-surgical rehabilitation phase - refer to physiotherapy for progressive strengthening and functional restoration protocol
- •Delayed presentation (>2 weeks) with complete rupture - may require specialized orthopedic management as primary repair window is closed
- •Signs of compartment syndrome including severe pain, swelling, paresthesias, or neurovascular compromise - emergency surgical consultation
- •Recurrent or bilateral ruptures suggesting systemic inflammatory disease - rheumatology referral
- •Chronic pain or functional limitations persisting beyond expected recovery timeline - pain management and psychology support
- •Failed conservative management after 6-8 weeks - return to orthopedic specialist for reassessment of surgical options