The Thompson Test assesses Achilles tendon continuity by squeezing the calf and observing whether the foot plantarflexes. Lack of plantarflexion may suggest Achilles tendon rupture and should prompt appropriate medical assessment. Recent reviews describe Achilles rupture diagnosis as primarily clinical, supported by tests such as Thompson’s test, tendon palpation and resting tension assessment, with ultrasound or MRI used when confirmation or further detail is needed.
A client reports a sudden pop or snap in the back of the ankle while sprinting, jumping, changing direction or pushing off. They may say it felt like being kicked in the calf. They may still be able to walk, which can make the injury easy to underestimate.
The Thompson Test is a key screen for Achilles tendon rupture. A positive result should be treated seriously and should prompt referral or medical review rather than continued loading.
Test name: Thompson Test
Also known as: Simmonds-Thompson Test, Calf Squeeze Test
Body region: Achilles tendon, calf, ankle
Purpose: Assess Achilles tendon continuity
Positive finding: No or reduced plantarflexion when the calf is squeezed compared with the other side
Negative finding: Plantarflexion occurs when the calf is squeezed
Best used with: Achilles palpation, resting ankle angle, Matles-type assessment, walking ability, mechanism of injury and ultrasound/referral when indicated
Key limitation: Partial, chronic or atypical ruptures may not be identified clearly
The Thompson Test is performed by squeezing the calf and observing whether the ankle plantarflexes. If the Achilles tendon is intact, calf squeeze should transmit force through the tendon and produce plantarflexion.
If plantarflexion is absent or greatly reduced, Achilles tendon rupture should be suspected.
The test is used when Achilles tendon rupture is suspected after sudden posterior ankle or calf injury.
It may be relevant after sprinting, jumping, racquet sport, football, basketball, netball, sudden push-off, missed step or sudden calf pain with a snap sensation.
The test assesses functional continuity of the Achilles tendon-calf complex. It does not identify exact tear location, gap size, partial tear status or treatment pathway.
This test may be useful for adults with sudden posterior ankle pain, calf pop, suspected Achilles rupture, inability to push off, reduced calf strength or a traumatic Achilles mechanism.
Use when Achilles rupture is suspected and the client can be positioned safely.
Use caution with severe pain, acute trauma, suspected fracture, recent surgery, open wound, marked swelling, vascular symptoms or inability to position safely.
If Achilles rupture is suspected, avoid repeated testing or loaded calf activity.
Treatment table
Pain scale
Measurz recording workflow
Optional referral notes
Optional comparison-side notes
Position the client prone with the feet hanging over the edge of the table, or kneeling on a chair/table depending on the setting.
The ankles should relax naturally.
Stand beside the lower leg.
Place one hand around the calf muscle belly.
Allow the foot to move freely.
Squeeze the calf and observe the ankle response.
Ask the client to remain relaxed and report pain if present.
A positive Thompson Test is absent or clearly reduced plantarflexion compared with the other side when the calf is squeezed.
A negative test is visible plantarflexion with calf squeeze.
Stop if pain is severe, positioning is not tolerated or rupture is strongly suspected.
Do not ask the client to perform repeated calf raises if rupture is suspected.
A positive Thompson Test may strongly suggest Achilles tendon rupture and should prompt referral or medical assessment. It is especially concerning when paired with a sudden pop, palpable gap, reduced resting plantarflexion and inability to push off.
A negative test makes complete rupture less likely, but it does not fully exclude partial rupture, chronic rupture or atypical presentation. If suspicion remains high, further assessment and imaging may still be required.
A 2022 evidence-based review reported that physical examination for complete Achilles tendon rupture using clinical manoeuvres including Thompson’s test, decreased resting tension and palpable tendon defect showed sensitivity between 73% and 96%.
Condition or presentation: suspected complete Achilles tendon rupture
Population: people with acute Achilles tendon injury
Test variation: Thompson/Simmonds calf squeeze test, often interpreted with other clinical signs
Reference standard: clinical diagnosis, imaging or surgical confirmation depending on study
Sensitivity: reported within broader clinical examination range of 73% to 96%
Specificity: not provided in the accessible review summary for Thompson’s test alone
Positive likelihood ratio: not available from the accessible summary
Negative likelihood ratio: not available from the accessible summary
Key limitations: partial tears, chronic tears, accessory plantarflexors, swelling, examiner interpretation and variation in reference standards
Recent summaries continue to describe Achilles rupture diagnosis as primarily clinical, with Thompson’s test, palpation and resting tension assessment used alongside ultrasound or MRI where needed.
Reliability depends on client relaxation, foot position, squeeze force, comparison with the other side and whether the examiner observes ankle movement carefully.
Validity is strongest for complete ruptures and weaker for partial or chronic presentations.
Common errors include testing while the client is not relaxed, not comparing sides, assuming walking ability rules out rupture, missing partial rupture and continuing calf loading after a positive test.
Limitations include partial tears, chronic injury, pain guarding, swelling and contribution from other plantarflexor muscles.
Use the Thompson Test as a safety-critical screen when Achilles rupture is possible. A positive or suspicious result should lead to referral rather than loading progression.
Record test name, side tested, result, plantarflexion response, comparison side, pain score, mechanism of injury, pop/snap sensation, palpable gap, resting ankle position, walking ability, calf raise ability if already assessed, confidence in result and referral recommendation.
Add imaging/referral notes and avoid progress-testing until rupture has been appropriately assessed.
Silfverskiöld Test
Single Leg Calf Raise
Ankle Plantarflexion Test
Ankle Dorsiflexion Test
Windlass Test
Balance and Proprioception Tests
Hop Tests
Calf Strength Testing
It assesses whether calf squeeze produces ankle plantarflexion, which suggests Achilles tendon continuity.
A positive result is absent or clearly reduced plantarflexion when the calf is squeezed.
Yes. Walking may still be possible, so walking ability alone should not rule out rupture.
No. Partial or chronic ruptures may not be detected clearly.
Record side, plantarflexion response, comparison side, mechanism, pain, palpable gap, resting angle and referral recommendation.
The Thompson Test is a key clinical screen for Achilles tendon rupture.
Absent plantarflexion with calf squeeze is a concerning finding.
Walking ability does not rule out rupture.
Partial or chronic ruptures may require further assessment.
Measurz should capture mechanism, response, comparison side and referral notes.
Amlang, M., et al. (2024). Acute rupture of the Achilles tendon: Diagnostics, treatment and rehabilitation. Orthopädie. Needs verification.
