8.1 Foot & Ankle Assessment
Key Takeaways
- Anterior drawer stresses the ATFL in plantarflexion; talar tilt/inversion in dorsiflexion stresses the CFL; the PTFL is the strongest lateral ligament and is rarely injured in isolation
- Syndesmosis (high ankle) testing is squeeze, external-rotation/Kleiger, and Cotton/lateral translation — a positive cluster is not a 5-day lateral sprain
- Ottawa Ankle Rules use the posterior 6 cm or tip of each malleolus; Ottawa Foot Rules use the navicular and the base of the fifth metatarsal, plus inability to take four steps immediately and in the exam area
- Lisfranc injury presents with midfoot pain and often plantar ecchymosis — keep the athlete non-weight-bearing and image; do not walk it off
- Acute compartment syndrome is a surgical emergency (pain out of proportion plus the 6 Ps); Thompson plus a palpable gap diagnoses Achilles rupture at the sideline
Practice Analysis, 8th Edition (PA8) Domain II, task 0202, asks the athletic trainer to perform a physical examination using appropriate diagnostic techniques. At the foot and ankle that means naming the ligament you are stressing, applying Ottawa bony landmarks instead of “it looks swollen,” and recognizing the injuries that are not a 5-day lateral sprain: syndesmosis, Lisfranc, Jones fracture, Achilles rupture, and compartment syndrome.
Start With Mechanism and Weight-Bearing
History still drives the exam. Inversion plus plantarflexion loads the anterior talofibular ligament (ATFL) first. Inversion in dorsiflexion loads the calcaneofibular ligament (CFL). Dorsiflexion plus external rotation (a planted, cutting, or tackle-with-the-foot-stuck mechanism) loads the syndesmosis. A forced hyperextension of the first metatarsophalangeal (MTP) joint on artificial turf is turf toe. A twist on a plantarflexed, forefoot-planted foot is a Lisfranc mechanism until you prove otherwise.
Ask whether the athlete took four steps immediately and whether they can take four steps now. That single fact is both an Ottawa item and a functional screen. Observe swelling location (lateral gutter versus syndesmosis versus midfoot), deformity, and plantar midfoot ecchymosis — a red-flag clue for Lisfranc injury, not a cosmetic bruise.
Lateral Complex: ATFL, CFL, PTFL
The lateral ligament complex has a predictable injury order and a matching test battery:
| Ligament | Role | Best clinical stress |
|---|---|---|
| ATFL | Primary restraint to anterior talar translation in plantarflexion; most commonly sprained | Anterior drawer (knee flexed, ankle ~10–20° plantarflexion, talus drawn anteriorly on the tibia) |
| CFL | Restrains inversion of the talus/calcaneus in dorsiflexion | Talar tilt / inversion stress with the ankle nearer dorsiflexion |
| PTFL | Strongest of the three; posterior-lateral restraint; rarely isolated | Posterior translation / extreme inversion-dorsiflexion cluster; think associated severe sprain or dislocation |
A positive anterior drawer (increased translation, a clunk, or a soft end-feel compared with the opposite side) supports ATFL insufficiency. It does not grade a tear the way an MRI report does, and it does not clear the syndesmosis. Talar tilt that opens the lateral talar dome compared with the opposite side implicates the CFL. Combine both tests, palpate the ligaments, and still apply Ottawa — ligaments and fractures coexist.
Syndesmosis: Squeeze, Kleiger, Cotton
The distal tibiofibular syndesmosis (anterior-inferior tibiofibular ligament, posterior-inferior tibiofibular ligament, interosseous ligament/membrane, and transverse tibiofibular ligament) is the “high ankle.” Test it on purpose:
- Squeeze (Hopkin) test: Compress the tibia and fibula at mid-calf. Pain at the distal syndesmosis, not at the squeeze site, is the positive finding.
- External-rotation / Kleiger test: Stabilize the tibia and externally rotate the foot (often in dorsiflexion). Anterolateral ankle or syndesmotic pain is positive; medial pain can also implicate the deltoid.
- Cotton (lateral translation) test: Grasp the calcaneus/talus and translate the talus laterally in the mortise. Increased translation or mortise pain suggests syndesmotic incompetence.
Exam trap: treating a squeeze-positive, Kleiger-positive athlete like a 5-day lateral sprain. Isolated ATFL sprains often return to play in days when pain, swelling, and hop/cut tolerance allow. Syndesmosis injuries disrupt the mortise; they need a longer, criterion-based progression (often weeks, not days), and unstable mortise injuries need physician referral, not a tape-and-go plan.
Achilles: Thompson and the Gap
For a sudden “pop” in the posterior calf or heel during push-off, prone the athlete and perform a Thompson (calf-squeeze) test. Absent or markedly reduced passive plantarflexion compared with the opposite side is a rupture until proven otherwise. Palpate for a gap in the tendon 2–6 cm above the insertion. Do not force stretch or eccentric loading to “confirm” a complete tear on the sideline. Splint in gravity equinus, non-weight-bear, and refer. A negative Thompson does not erase a partial tear — but a positive Thompson plus a gap is a sideline diagnosis that should change the plan immediately.
Ottawa Ankle and Foot Rules — Teach the Actual Landmarks
Swelling is not an imaging indication. Stiell’s Ottawa Ankle and Foot Rules are. Palpate the posterior edges, not the anterior swollen gutter.
Ankle radiographic series is indicated if there is pain in the malleolar zone and any one of:
- Bone tenderness along the distal 6 cm of the posterior edge of the tibia or the tip of the medial malleolus, or
- Bone tenderness along the distal 6 cm of the posterior edge of the fibula or the tip of the lateral malleolus, or
- Inability to bear weight both immediately after injury and in the examination area for four steps (limping still counts as bearing weight if four steps are completed).
Foot radiographic series is indicated if there is pain in the midfoot zone and any one of:
- Bone tenderness at the base of the fifth metatarsal, or
- Bone tenderness at the navicular, or
- Inability to bear weight both immediately and in the examination area for four steps.
Palpate the entire posterior 6 cm, not a single fingertip on the tip. Medial malleolar tenderness counts. Ottawa is a rule-out tool (high sensitivity): if no criterion is present, clinically significant fracture is very unlikely and you should not irradiate “because it is swollen.” If any criterion is present, recommend the matching series and refer — clinical judgment can still image a high-risk exam even when the rule is negative (intoxication, unreliable exam, delayed presentation caveats).
High-Ankle Versus Lateral Sprain Return
| Feature | Lateral (ATFL ± CFL) sprain | Syndesmotic (high ankle) sprain |
|---|---|---|
| Mechanism | Inversion, often plantarflexed | Dorsiflexion + external rotation |
| Key tests | Anterior drawer, talar tilt | Squeeze, Kleiger, Cotton |
| Mortise | Stable | At risk of widening |
| Typical RTP | Days for mild, criterion-based hop/cut | Meaningfully longer; unstable injuries need imaging and physician-directed care |
Return is criterion-based (pain-free gait, full functional ROM, hop and change-of-direction tolerance, sport-specific load), not a calendar. The BOC item writes itself when someone “returns the squeeze-positive athlete Friday because lateral sprains are a 5-day injury.”
Lisfranc: Midfoot Pain and Plantar Ecchymosis
The Lisfranc complex is the tarsometatarsal joints plus the Lisfranc ligament (medial cuneiform to the base of the second metatarsal). Suspect it with midfoot pain after an axial or twisting load on a plantarflexed foot, inability to push off, and especially plantar ecchymosis. Weight-bearing is both a test and a risk: keep the athlete non-weight-bearing and refer for imaging (weight-bearing radiographs if they can be obtained safely; CT or MRI when radiographs are negative but suspicion remains). Walking off a Lisfranc injury is how midfoot instability and post-traumatic arthritis get missed.
Fifth Metatarsal: Avulsion Versus Jones Versus Stress
Lawrence–Botte zones of the proximal fifth metatarsal:
| Zone | Location | Typical injury | Healing implication |
|---|---|---|---|
| 1 | Tuberosity / styloid | Avulsion (peroneus brevis and/or plantar fascia lateral band), often with inversion | Usually good healing; conservative walking boot often appropriate |
| 2 | Metaphyseal–diaphyseal junction (4th–5th metatarsal articulation) | Jones fracture | Watershed blood supply; delayed union / nonunion risk; athletes often need surgical discussion |
| 3 | Proximal diaphysis | Stress fracture | Also delayed healing; stop the running load and refer |
Ottawa base-of-fifth tenderness triggers a foot series — then you still have to name the zone on the film with the physician. Do not treat a Jones like a tuberosity avulsion.
Plantar Heel: Fasciopathy Versus Tarsal Tunnel Versus Baxter
Plantar fasciopathy is activity-related plantar-medial heel pain, classically first-step pain in the morning, tenderness at the medial calcaneal tubercle, and pain with windlass (dorsiflexion of the first MTP). Tarsal tunnel syndrome is tibial-nerve compression under the flexor retinaculum: burning or paresthesia into the sole, a positive Tinel behind the medial malleolus, and symptoms that may worsen at night or with sustained dorsiflexion–eversion. Baxter neuropathy (first branch of the lateral plantar nerve) mimics plantar fascia with medial heel pain and can add abductor digiti minimi weakness — it is not “just fascia.” Screen lumbar radiculopathy when heel pain is neurologic and poorly localized.
Turf Toe
Turf toe is a hyperextension sprain of the first MTP plantar plate / sesamoid complex. Grade by tissue and function: stretch with minimal swelling (often play with a stiff insert), partial tear with limited push-off, and complete disruption that needs protected non-weight-bearing and physician referral. 1st MTP dorsal pain after hyperflexion is a different (dorsal capsule) problem; do not lump every great-toe sprain as turf toe.
Compartment Syndrome — Pain Out of Proportion
Acute compartment syndrome is a surgical emergency. Classic 6 Ps: Pain (out of proportion, worse with passive stretch of the muscles in that compartment), Paresthesia, Pallor, Paralysis, Pulselessness, and Poikilothermia (cool). Pain and pain on passive stretch appear early; pulselessness is late — do not wait for a missing pulse. Splint, remove constricting wraps, and activate EMS / surgical referral. Chronic exertional compartment syndrome is a different, activity-related tightness that eases with rest; it is not an on-field fasciotomy, but it is also not “shin splints.”
Medial Tibial Stress Syndrome Versus Stress Fracture
Medial tibial stress syndrome (MTSS) is typically diffuse posteromedial tibial pain along a several-centimeter border. A tibial stress fracture is focal tenderness, often with hop-test pain and night or at-rest pain. The tuning fork is not the gold-standard test. Early radiographs are often normal. MRI is the preferred confirmatory study for bone-stress injury; bone scan is historically used but is less specific. Hop pain plus focal tenderness is a refer and unload decision, not a “run through it” decision.
Put the whole exam in one sentence for the test: cluster the ligament, palpate Ottawa bone, and do not return a high-ankle, Lisfranc, Jones, Achilles, compartment, or bone-stress injury on a lateral-sprain calendar.
A basketball player inverts the ankle, lands, and walks to the bench with a limp. The ATFL is tender, anterior drawer is increased versus the opposite side, the squeeze and Kleiger tests are painless, the posterior 6 cm of both malleoli plus the navicular and fifth-metatarsal base are nontender, and the athlete completed four steps immediately and again in the exam area. What is the best athletic-training interpretation?
Which landmarks and functional finding make the Ottawa Ankle and Foot Rules positive when the matching pain zone is present?
A midfielder twists on a planted, plantarflexed foot. There is midfoot pain, plantar ecchymosis, and inability to push off. Anterior drawer and talar tilt are unremarkable, and the squeeze test is negative. What is the priority?