✅ Medically reviewed by Dr. Tom Biernacki, DPM — Board-certified podiatrist specializing in foot & ankle surgery. View credentials.
What Are the Peroneal Tendons? For specialized treatment, see our peroneal tendon treatment Michigan.
The peroneal tendons—peroneus longus and peroneus brevis—run behind the lateral (outer) ankle and down to the foot, where they attach to the base of the fifth metatarsal (peroneus brevis) and the undersurface of the first metatarsal and medial cuneiform (peroneus longus). Together they evert the foot (turn the sole outward) and stabilize the ankle against inversion. They are dynamic stabilizers of the lateral ankle, working in conjunction with the lateral ankle ligaments. Peroneal tendon injuries—tears, tendinopathy, and subluxation—are a frequently underdiagnosed cause of lateral ankle pain that is commonly mistaken for a recurrent ankle sprain.
Types of Peroneal Tendon Injuries
Peroneal Tendinopathy
Chronic tendinopathy (degeneration without complete tearing) is the most common peroneal injury. It causes persistent lateral ankle aching, pain behind or around the lateral malleolus, swelling along the tendon course, and pain that worsens with activity. It develops from repetitive overuse (common in runners and athletes), prior ankle sprains that load the peroneals abnormally, or from a cavus (high-arch) foot type that increases lateral loading. Initial treatment focuses on activity modification, physical therapy for eccentric strengthening and flexibility, and orthotic support. A short period of immobilization may be needed for acute flares.
Peroneus Brevis Longitudinal Split Tear
The peroneus brevis tendon frequently tears longitudinally—splitting into two strips—as it wraps around the posterior lateral malleolus. This mechanism occurs because the brevis is compressed against the bone when the peroneus longus (which also runs in the same fibro-osseous groove) is under tension. Longitudinal split tears are associated with ankle instability, peroneal subluxation, and high-arch feet. Symptoms include lateral ankle pain, swelling behind the malleolus, pain with resisted eversion, and occasional snapping. MRI demonstrates the split in the tendon and characterizes the extent of damage.
Peroneus Longus Tear
Peroneus longus tears most commonly occur at two sites: at the level of the os peroneum (a sesamoid bone in the longus tendon near the cuboid tunnel) or at the proximal musculotendinous junction. Injury at the os peroneum level can cause a painful os peroneum syndrome with foot pain along the lateral midfoot and sole. Complete peroneus longus rupture produces weakness in plantarflexion of the first ray (the big toe side of the foot). MRI with dedicated ankle protocol is essential for accurate diagnosis and surgical planning.
Peroneal Tendon Subluxation
Peroneal tendon subluxation occurs when the superior peroneal retinaculum—the ligament that holds the peroneal tendons in the groove behind the lateral malleolus—is torn, allowing the tendons to snap forward over the malleolus. Patients feel and sometimes hear a snapping or popping sensation at the outer ankle with plantarflexion and eversion. It commonly occurs with acute ankle dorsiflexion injuries (skiing, football). The tendons may be visibly or palpably subluxing during examination. Acute cases may be treated with immobilization; recurrent or chronic subluxation typically requires surgical repair of the retinaculum with possible bony groove deepening (retromalleolar groove deepening).
Treatment: Conservative and Surgical
Conservative treatment for peroneal tendinopathy and partial tears includes activity modification, physical therapy focusing on eccentric strengthening and range of motion, anti-inflammatory medication, and orthotics with a lateral heel post to reduce inversion stress. A lateral wedge in the shoe transfers load medially and reduces peroneal activation. Corticosteroid injection into the peroneal tendon sheath can reduce acute inflammation, but injection directly into the tendon is avoided due to rupture risk. Most partial peroneal tears with mild-to-moderate symptoms can be managed non-operatively with these measures.
Surgical treatment is indicated for complete tears, large partial tears failing conservative treatment, chronic subluxation, and tears associated with debilitating ankle instability. Peroneal repair involves debridement of degenerated tissue, repair of longitudinal tears with side-to-side suture, or tenodesis (sewing the damaged tendon to the intact adjacent tendon) for non-repairable segments. Concurrent ligament reconstruction is often performed when instability coexists. Recovery after peroneal surgery involves immobilization for 4–6 weeks, progressive weight-bearing, and physical therapy from 8–12 weeks. Return to full activity takes 4–6 months.
Frequently Asked Questions
Can a peroneal tendon tear heal on its own?
Partial peroneal tendon tears with longitudinal splits can stabilize and become pain-free with conservative treatment, though they do not typically “heal” in the sense of restoring the original tendon architecture—the split persists but may become asymptomatic with degenerated tissue stabilized by scar. Small partial tears in patients without significant instability often respond well to non-operative management (physical therapy, activity modification, orthotics), with 6–12 months of consistent treatment. Complete tears do not heal without surgery. The key is accurate diagnosis with MRI—trying to manage a complete tear conservatively leads to prolonged symptoms and may allow the tendon end to retract, making eventual repair more difficult.
Is peroneal tendon pain the same as a lateral ankle sprain?
No, though they share a location and are often confused. A lateral ankle sprain injures the ankle ligaments (ATFL and CFL), while peroneal tendon injury involves the tendons that run behind and below the lateral malleolus. The tenderness location is different: ligament sprains are tender over the ligament itself (typically anterior to and below the lateral malleolus), while peroneal tendon injuries are tender in the groove directly behind the lateral malleolus and along the tendon course toward the foot. Peroneal tendon injury is often co-diagnosed with ankle sprain—approximately 20–30% of lateral ankle sprains involve concurrent peroneal tendon injury. MRI is needed to distinguish the two when symptoms are persistent or atypical.
What does peroneal tendon snapping mean?
Snapping or popping behind or around the lateral ankle with ankle movement suggests peroneal tendon subluxation—the tendons are intermittently slipping out of the fibro-osseous groove behind the lateral malleolus. This occurs when the superior peroneal retinaculum (the tissue that holds the tendons in place) has been torn. It can also occur within an unstable tendon sheath with a longitudinal split tear. Peroneal subluxation is reproducible on examination and can often be demonstrated by asking the patient to actively evert the foot against resistance while the examiner palpates the posterior malleolus. Snapping that is painful and reproducible warrants imaging evaluation and consideration of surgical stabilization if symptoms persist.
Medical References & Sources
- American Orthopaedic Foot & Ankle Society — Peroneal Tendon Injuries
- PubMed Research — Peroneal Tendon Repair Outcomes
- PubMed Research — Peroneal Subluxation Treatment
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Dr. Tom Biernacki, DPM is a board-certified podiatric surgeon at Balance Foot & Ankle in Howell and Bloomfield Hills, Michigan. He evaluates and treats peroneal tendon injuries including tendinopathy, longitudinal tears, and subluxation with conservative management and surgical repair.
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Our board-certified podiatrists treat this condition at two convenient locations. Same-day appointments often available.
Medically Reviewed by: Dr. Jeffery Agnoli, DPM — Board-Certified Podiatrist, Balance Foot & Ankle Specialists
Peroneal Tendon Tear — Expert Diagnosis & Repair
Peroneal tendon injuries can cause chronic ankle instability and pain. Our surgeons specialize in both conservative and surgical repair of peroneal tendon tears.
Clinical References
- Dombek MF et al. Peroneal tendon tears: a retrospective review. J Foot Ankle Surg. 2003;42(5):250-258.
- Redfern D, Myerson M. The management of concomitant tears of the peroneus longus and brevis tendons. Foot Ankle Int. 2004;25(10):695-707.
- Heckman DS et al. Tendon disorders of the foot and ankle, part 2: peroneal tendon disorders. Am J Sports Med. 2009;37(6):1175-1184.
Dr. Tom Biernacki, DPM is a double board-certified podiatrist and foot & ankle surgeon at Balance Foot & Ankle Specialists in Southeast Michigan. With over a decade of clinical experience, he specializes in heel pain, bunions, diabetic foot care, sports injuries, and minimally invasive surgery. Dr. Biernacki is a member of the APMA and ACFAS, and his patient education content on MichiganFootDoctors.com and YouTube has reached over one million views.
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