Ankle — Fast Exam

Tap a diagnosis. Tests first, interpretation underneath.

30-second screen

Run this before any special testOttawa rules → where the pain is → weight-bearing → tendons

Ottawa ankle rules first if there was trauma. Tender over the posterior lateral or medial malleolus, or the navicular or base of the 5th metatarsal → radiograph. Do not test ligaments before you have excluded a fracture.
Can they weight-bear four steps? If not, add the foot rules and image.
Ask them to point. Lateral → sprain or peroneal. Anterior between the bones → syndesmosis. Posterior → Achilles. Medial → deltoid or tibialis posterior. Inferior heel → plantar fascia.
Is there bruising and swelling above the joint line? → syndesmosis until proven otherwise. Those are the ones that take months.
Resisted testing in each direction — eversion (peroneal), inversion (tibialis posterior), plantarflexion (Achilles, calf).
Thompson test on every posterior ankle. It takes seconds and a missed Achilles rupture is unrecoverable.
Single-leg heel raise — the functional test that ties the tendon picture together.

The honest caveat: ankle ligament tests are moderate at best and depend on your hands and the patient's relaxation. The Ottawa rules are the one genuinely robust thing in this region — use them properly and spare the patient an unnecessary ligament examination after a fracture.

Lateral

Lateral ankle sprain (ATFL / CFL)Inversion injury, lateral swelling, tender in front of the lateral malleolus

Hallmark

An inversion injury, swelling lateral and anterior to the malleolus, and difficulty weight-bearing. The anterior talofibular ligament is injured first and most often; the calcaneofibular ligament follows.

Tests — do these 4–7 days after the injury, not on the swollen acute ankle

Anterior drawer at the ankle — 10–20° plantarflexion, stabilise the tibia, draw the talus anteriorly. Positive: increased anterior translation compared with the other side, especially with a soft endpoint. Sn 32–80% / Sp 80%
Talar tilt — invert the talus with the ankle in 10–20° dorsiflexion for the calcaneofibular ligament, and in plantarflexion for the anterior talofibular. Positive: excessive gapping versus the other side. Sn 50% / Sp 88% (Hertel) — a positive is more useful than a negative
Palpation of the ligament — Positive: focal tenderness over the specific ligament. Genuinely underrated: it localises the injury better than either stress test.

Next: grade by the presence of a firm endpoint and by how long they were unable to weight-bear, not by how dramatic the swelling looks. Re-examine at day 5 — that is when the stress tests become meaningful.

Chronic ankle instabilityRepeated sprains, repeated giving way, never fully trusted since

Hallmark

Recurrent giving way, especially on uneven ground, with a sense of the ankle not being trustworthy. Often normal on static testing — the problem shows up under load.

Tests

Repeated single-leg hop, then landing — Positive: giving-way sensation or poor control → functional instability.
Star excursion / Y-balance reach — measure the reach deficit against the other side. More useful as a rehabilitation outcome than a diagnosis.
Anterior drawer and talar tilt — Positive: mechanical laxity. Note that many patients have laxity with no symptoms, and many with symptoms have no laxity.

Next: separate mechanical from functional instability — it changes what you treat. Most respond to a proper balance and peroneal programme, and most are under-rehabilitated rather than beyond help.

Syndesmosis

High ankle sprain (syndesmosis)Pain above the joint line, external rotation mechanism, slow to settle

Hallmark

Pain between the tibia and fibula, above the ankle joint line — not over the lateral ligaments. Mechanism is usually external rotation of the foot with the leg fixed, or a forced dorsiflexion. Swelling may be modest while the pain is severe.

Tests

Squeeze test — compress the tibia and fibula together at mid-calf. Positive: pain at the syndesmosis, well above the joint line. Simple, and rarely falsely positive.
External rotation stress — knee at 90°, ankle neutral, externally rotate the foot. Positive: pain at the anterior syndesmosis.
Cotton test — translate the fibula laterally in a drawer fashion. Positive: increased translation and pain.
Crossed-leg test — rest the mid-calf of the affected leg on the other knee and push down. Positive: pain at the syndesmosis.

Next: this is the ankle injury that gets missed and then takes three times as long. If the pain is above the joint line, or the mechanism was external rotation, treat it as a syndesmosis and weight-bear in a boot. Radiograph to exclude a fracture; a true diastasis needs an orthopaedic opinion.

Tendon

Achilles ruptureA pop, then cannot push off — and the gap is the diagnosis

Hallmark

A sudden pop with the sensation of being struck from behind, then an inability to push off or stand on tiptoe. Often in a middle-aged recreational athlete. Note that they can usually still walk.

Tests

Thompson (Simmonds) test — squeeze the calf with the patient prone and the foot relaxed. Positive: no plantarflexion → rupture. the single most reliable sign in this region
Palpable gap and Matles test — prone, knees 90°. Positive: the foot falls into more dorsiflexion than the other side, and a defect is palpable 2–6 cm above the insertion.
Single-leg heel raise — if they can do it fully, the tendon is intact. A partial rupture can still produce a weak, painful heel raise.

Next: do not be reassured by a patient who walks in. The Thompson test takes five seconds and a missed rupture is a different, worse recovery. If there is any doubt, ultrasound or a referral.

Achilles tendinopathyMorning stiffness and pain 2–6 cm above the insertion

Tests

Palpation of the tendon — Positive: focal thickening and tenderness 2–6 cm above the insertion (mid-portion) or at the insertion itself. The location determines the rehabilitation: mid-portion versus insertional need different loading.
Single-leg heel raise, then 10 repetitions — Positive: pain and, later, weakness.
Royal London Hospital test — palpate in dorsiflexion and plantarflexion. Positive: tenderness present in one position and absent in the other.

Next: a clinical diagnosis. Imaging only if you suspect rupture or are planning an intervention. Progressive loading is the treatment; rest alone makes it worse.

Peroneal tendinopathy and subluxationPosterior to the lateral malleolus — behind, not in front

Tests

Palpation behind the lateral malleolus — Positive: focal tenderness. The location behind the malleolus is what separates it from a lateral ligament sprain, which hurts in front and below.
Resisted eversion — Positive: pain or weakness along the tendons.
Peroneal subluxation test — dorsiflex and evert against resistance, or circumduct the ankle. Positive: a palpable snap of the tendons over the malleolus.

Next: commonly missed after a lateral sprain, because the ankle is swollen and the lateral ligaments get all the attention. Palpate behind the malleolus in every stubborn "sprain".

Posterior tibial tendon dysfunctionMedial ankle pain, collapsing arch, can't do a single heel raise

Tests

Single-leg heel raise — the key test. Positive: cannot perform it, or the heel does not invert as it rises → tendon failure.
Too-many-toes sign — Positive: more toes visible from behind on the affected side → progressive flatfoot deformity.
Resisted inversion in plantarflexion — Positive: pain or weakness.
Palpation behind the medial malleolus — Positive: focal tenderness and thickening.

Next: this is a progressive deformity, not a self-limiting tendonitis. If they cannot do a single heel raise, act now — orthotics and loading, and refer early rather than late.

Other

Plantar heel painFirst-step pain under the heel, worst in the morning

Tests

Palpation of the medial calcaneal tubercle — Positive: focal tenderness at the origin. The most useful finding.
Windlass test — passively extend the toes, especially the first. Positive: reproduction of the heel pain.
Foot posture and calf length — a tight gastrocnemius or soleus is the modifiable contributor in most cases.

Next: clinical diagnosis. Classic history is first-step pain on getting out of bed. Loading — not stretching alone — resolves it; most cases settle over months, not weeks. Beware bilateral heel pain with inflammatory features or in a young athletic patient: think spondyloarthropathy or a stress fracture instead.

Ankle impingementPinching pain at the front of the ankle on deep dorsiflexion

Tests

Anterior impingement sign — force the ankle into maximum dorsiflexion. Positive: sharp anterior pain reproduced: bone spurs and soft tissue caught between tibia and talus.
Posterior impingement sign — maximal plantarflexion, often in a plantarflexed first-ray position. Positive: posterior pain — common in dancers and footballers.

Next: common after old sprains and in people with a lot of end-range loading. Radiograph for anterior osteophytes.

Choosing the imagingOttawa rules decide the radiograph — not your gut

Ottawa ankle and foot rules — the one genuinely robust decision tool here. Radiograph if there is pain near the posterior malleolus (lateral or medial), the navicular, or the base of the 5th metatarsal, or if they cannot take four steps. Applying them properly is the single biggest quality gain in this region.
Radiograph — trauma, suspected fracture, chronic deformity, or a syndesmosis to exclude diastasis.
Ultrasound — tendons and guided injection. Excellent for Achilles and peroneal tendons.
MRI — occult fracture, osteochondral lesion, a suspected syndesmosis, or persistent pain with normal plain films.

Worth remembering: an osteochondral lesion of the talus is a classic cause of a persistently painful ankle after a "simple" sprain that has not settled by three months. If it stops improving, image it.

Red flags — before you test

Re-route before you testSix findings that take precedence over any special test

Stop and re-route

Cannot weight-bear, or bony tenderness at the malleoli, navicular or 5th metatarsal base → fracture. Radiograph. Ottawa rules.
Hot, red, swollen ankle with fever → septic arthritis or cellulitis. Urgent.
Achilles gap, or a positive Thompson with weakness → rupture. Do not send home as a sprain. Discuss with orthopaedics.
Sudden severe pain in a patient on anticoagulants or with a plaster cast → compartment syndrome. Emergency.
Calf swelling and tenderness after immobilisation, surgery or prolonged travel → deep vein thrombosis.
Inability to bear weight with inability to bear weight for three months after an apparently minor sprain → osteochondral lesion or occult fracture. Image further, don't reassure.

Built for Ruby — PRM & sports medicine ankle and foot reference.
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Sources. [1] Stress tests for ankle ligaments — Physiopedia: anterior drawer Sn 32–80% / Sp 80%. [2] Talar tilt — Hertel et al. 1999: Sn 50% / Sp 88% for lateral ankle sprain; Rosen et al. 2015 found Sn 4% with specificity 78–88% for detecting talocrural and subtalar instability. [3] Physical examination of the ankle, review of original descriptions — Larkins et al. 2020 (PMC7853358): anterolateral drawer with a 3 mm translation threshold reported 100% sensitivity and specificity. [4] Ottawa ankle and foot rules — the decision tool for radiography after ankle trauma. [5] Individual tests without figures above are described from standard technique. Where the literature does not provide robust accuracy data, none is quoted rather than inventing one.

Diagnostic accuracy figures are pooled from the cited literature and vary widely between studies and populations. Interpret alongside history and pre-test probability. Not a decision-support system, and not a substitute for your own clinical judgement or local protocols.