Peroneal tendon tear test: Step-by-step exam and template

Key takeaways

A peroneal tendon tear is a split or a rupture in one of the two tendons running behind the outer ankle bone.

No single maneuver confirms a tear, so the exam runs palpation, resisted eversion, a single-leg heel rise, and a subluxation check.

MRI confirms the diagnosis and sizes the tear, while dynamic ultrasound is better at catching tendons that slip inside the sheath.

Sobel grades I to III usually start with conservative care, and a grade IV rupture earns a surgical opinion.

Digital assessment forms in practice management software like Pabau keep every exam finding in the client record.

Peroneal tendon injuries are a common cause of lateral ankle pain in athletes and active patients. The peroneal tendon tear test is how you separate a tear from tendonitis, subluxation, or a ligament sprain. It follows the examination sequence used in the peer-reviewed orthopedic literature.

This guide covers the exam in order, how to read each positive finding, and when imaging is worth ordering. Whether you work in sports medicine, physical therapy, or an orthopedic practice, every finding below has a matching field on the downloadable form.

What is a peroneal tendon tear test?

A peroneal tendon tear test is a structured exam of the two tendons that run behind the outer ankle. Those tendons are the peroneus brevis and the peroneus longus. They stabilize the ankle and drive eversion, which turns the sole of the foot outward. A tear brings lateral ankle pain, swelling, and a feeling of instability.

No single maneuver settles the question. The exam combines provocative maneuvers with careful palpation and a functional test. You are trying to reproduce the pain, find weakness, and rule out the other causes of lateral ankle pain. Recording each result in digital assessment forms keeps the note defensible.

Anatomy: Peroneus brevis vs peroneus longus

Which tendon tore changes what you find on the exam, so start with the anatomy.

Both tendons sit in a groove behind the fibula and are held there by the superior peroneal retinaculum, known as the SPR. A lax SPR lets the tendons slip. A tear causes pain and a loss of strength. That difference decides the treatment plan.

Signs and symptoms of a peroneal tendon tear

Take the history before you touch the ankle. Patients usually describe an inversion injury, long-standing lateral instability, or pain that built up under repetitive load.

• Lateral ankle pain along the fibular groove or the lateral border of the ankle
• Swelling and bruising over the lateral ankle, especially in acute tears
• Weakness on foot eversion or plantarflexion
• Instability, or a sense that the ankle gives way
• Trouble walking or running on uneven ground
• Pain on inversion where a ligament injury sits alongside the tendon problem

Acute tears arrive with sudden pain and swelling. Chronic tears build slowly and get mistaken for peroneal tendonitis. Your client record should carry the onset, the mechanism, and what the patient can no longer do.

How to perform the peroneal tendon tear test: Step-by-step

Work in the same order every time. Inspection comes first, then palpation, then range of motion, then the provocative maneuvers. A physical therapy EMR keeps that order on screen, so no step gets skipped under time pressure.

1. Inspection. Look for swelling, discoloration, scars, or muscle wasting on the lateral ankle and lower leg. Note any asymmetry against the other side.
2. Palpation. Follow the tendons with your thumb, starting above the fibular head and working down to the ankle. Mark tender points, crepitus, and any palpable defect.
3. Range of motion. Assess plantarflexion, dorsiflexion, inversion, and eversion gently. Note pain, restriction, or weakness against the unaffected ankle.
4. Resisted eversion. The patient sits or lies with the knee flexed. Stabilize the ankle and resist as they evert the foot. Pain or weakness points at the peroneal tendons.
5. Single-leg heel rise. The patient stands on the affected leg and rises onto the ball of the foot. Failing to reach 10 repetitions without pain suggests real peroneal weakness.
6. Subluxation check. With the knee flexed and the hip turned out, press front to back over the tendons at the fibular groove. A palpable pop suggests SPR laxity rather than a tear.

How to read a positive finding

No maneuver here reaches 100% sensitivity or specificity. Read the findings together with the history and, where you have it, the imaging.

Classification of peroneal tendon tears

Two named systems get used here, and they answer different questions. The Sobel grading system scores how badly the peroneus brevis is split, running from grade I to grade IV.

Grade I is a flattened or attrited tendon with no split. Grade II is a split shorter than 1 cm, and grade III a split of 1 to 2 cm. Grade IV is a complete rupture.

Raikin’s classification describes something different. It covers intrasheath subluxation, where the tendons move inside a sheath that is still intact. Type A is two intact tendons swapping position. In type B, the peroneus longus slips through a split in the brevis.

The grade matters because it points at a route. Grades I to III usually start with conservative care, while a grade IV rupture earns a surgical opinion.

Record the grade, and the subluxation type where it applies, so the rest of the care team plans against the same pathology. Ankle injuries collect named systems like this. The Danis-Weber classification does the same job for fibular fractures.

Diagnostic imaging: MRI, ultrasound, and radiographs

Imaging confirms what the exam suspects. MRI is the standard for soft-tissue detail, tear size, and location. Ultrasound adds a moving picture and catches subluxation that a static scan can miss. Cleveland Clinic’s guidance treats the two as complementary.

• Plain radiographs. They rule out an avulsion fracture or other bone injury, but they are not sensitive for soft-tissue tears. Log the ankle radiograph results and move on to soft-tissue imaging.
• Musculoskeletal ultrasound. Real-time dynamic assessment, and the better option for spotting subluxation. It is operator-dependent, so the report quality varies.
• MRI. The highest soft-tissue resolution, and the best read on tear size, location, and chronicity. It is the standard for planning surgery.

Peroneal tendon tear vs tendonitis: Differential diagnosis

Treatment splits at this fork, so it is worth being sure. Tendonitis is inflammation with the tendon still intact. A tear is a break in continuity.

A palpable defect higher up the calf points at the Achilles instead, which is where the Thompson test earns its place. Once imaging is booked, patient scheduling software ties the scan and the review appointment to the same episode of care.

Treatment options: Conservative vs operative

Severity, chronicity, activity level, and the response to a conservative trial decide the route.

• Conservative management means immobilization in a CAM boot or ankle brace, limited weight-bearing for four to six weeks, ice, and anti-inflammatory medication. Rehab then targets peroneal strength and ankle proprioception.
• Operative treatment covers repair, tenodesis, or debridement. It is considered for complete ruptures, for a conservative trial that failed at six to twelve weeks, and for high-demand athletes.

Set the recovery window with the patient before they leave the room. A six-week boot and a four-month post-operative course are two different conversations, and the second one lands better early.

What’s inside the assessment template

The template gives you a checklist for the exam and somewhere to put each result. It carries fields for symptom history, palpation landmarks, provocative test results, imaging recommendations, and treatment planning.

Filling the same fields every time makes findings comparable between clinicians and between visits. It also means the note holds up if the case gets reviewed months later.

Pair it with automated workflow software to send the post-exam summary, book the imaging appointment, and check in during rehab. The same layout carries to other regions, so our quadriceps strain test form documents the thigh the same way.

How Pabau keeps the ankle assessment and its follow-up in one record

Most practices run this exam on paper and type a summary into the record hours later. The palpation map ends up in a drawer, the imaging request sits in an inbox, and the rehab notes live somewhere else again. Comparing week one with week six then means opening three systems.

Practice management software like Pabau keeps the episode together. The assessment form is a digital form the clinician fills in the room, so the findings save straight to the client record. Imaging requests, review appointments, and rehab measurements attach to that same client.

So when the patient comes back at week six, you have one place to look. You also have one export to hand over if a report is ever requested. Nothing gets retyped, and no finding sits in a drawer waiting to be filed.

Keep exam findings in the client record

Pabau’s digital forms capture peroneal tendon findings in the room and store them alongside the client’s imaging, appointments, and rehab progress. Your whole team works from one record.

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Conclusion

A peroneal tendon tear starts as a clinical suspicion that imaging then confirms, and the exam is what earns the scan. Run the same sequence every time and the pattern gets easy to spot.

What is worth remembering is that this exam narrows the possibilities without closing them. A palpable defect with weakness on resisted eversion still goes to MRI before anyone discusses surgery.

Standardizing the documentation is the cheap part of this, and it pays off at the review visit. A client portal also keeps the patient looking at their own rehab plan between appointments.

Book a demo to see how Pabau holds assessment findings, imaging, and rehab progress in one client record.

Continue your research

Assessing a knee instead? Apley’s test template walks through the grind and distraction sequence for a suspected meniscal tear.

Need the same structure for the thigh? Quadriceps strain test covers resisted extension, palpation landmarks, and grading.

Checking reflexes in the same workup? Deep tendon reflex exam gives you a grading scale and a place to record each side.

Measuring joint movement? Hip range of motion test shows how to log degrees consistently across visits.

Writing up the rehab visits? Progress note template keeps each session comparable to the one before it.

Frequently asked questions