Peroneal Tendon Injuries: Causes, Symptoms, Treatment, and Recovery — Foot & Ankle Specialist in North Texas

If you're experiencing pain on the outside of your ankle that won't go away — especially after an ankle sprain — you may have a peroneal tendon injury. Peroneal tendon problems are one of the most commonly missed diagnoses in foot and ankle medicine. Studies estimate that only 60% of peroneal tendon disorders are correctly identified on the first evaluation, with many cases being mistakenly treated as simple ankle sprains for months or even years before the true problem is found.

With offices in McKinney and Flower Mound, Dr. Sarang Desai provides expert diagnosis and treatment of peroneal tendon injuries for patients across Allen, Frisco, Plano, Prosper, and the greater Dallas-Fort Worth area. If you've been dealing with persistent lateral ankle pain that hasn't responded to typical ankle sprain treatment, a peroneal tendon problem may be the cause.

What Are the Peroneal Tendons?

The peroneal tendons are two tendons that run side by side along the outer (lateral) side of the ankle, just behind the bony bump on the outside of the ankle (the lateral malleolus):

- Peroneus brevis — the shorter tendon that inserts on the base of the fifth metatarsal (the bony bump on the outside of the midfoot). This is the more commonly injured of the two tendons.

- Peroneus longus — the longer tendon that crosses under the foot through a groove in the cuboid bone and inserts on the base of the first metatarsal and medial cuneiform on the inside of the foot.

Together, these tendons perform two critical functions:

1. Eversion — turning the foot outward, which is essential for walking on uneven surfaces and maintaining balance

2. Dynamic ankle stabilization — the peroneal tendons are the primary active stabilizers of the lateral ankle, working to prevent the ankle from rolling inward (inversion)

This is why peroneal tendon injuries and ankle sprains are so closely related — both involve the lateral ankle, and one can lead to the other. Repeated ankle sprains can damage the peroneal tendons, and weakened peroneal tendons can predispose to ankle instability.

Types of Peroneal Tendon Injuries

Peroneal tendon problems fall into several categories:

Peroneal tendinopathy (tendinitis/tendinosis):

The most common form. This involves irritation, inflammation, or degeneration of one or both peroneal tendons due to overuse or repetitive stress. It is particularly common in runners with a forefoot striking pattern, which places increased stress on the peroneal tendons.

Peroneal tenosynovitis:

Inflammation of the tendon sheath (the thin sleeve surrounding the tendons). This causes swelling, pain, and sometimes a grating or crepitus sensation along the tendons behind the ankle.

Peroneal tendon tears:

Partial or full-thickness tears of the tendon substance. The peroneus brevis is more commonly torn than the peroneus longus. Tears can result from acute trauma or develop gradually from chronic tendinopathy. Both tendons are rarely torn at the same time.

Peroneal tendon subluxation and dislocation:

The peroneal tendons are held in place behind the lateral malleolus by a band of tissue called the superior peroneal retinaculum (SPR). If this retinaculum is torn — usually during a forceful ankle dorsiflexion injury — the tendons can slip out of their groove and snap over the bone. This causes a painful popping or snapping sensation on the outside of the ankle.

What Causes Peroneal Tendon Injuries?

Peroneal tendon injuries result from a combination of acute trauma, overuse, and anatomic predisposition:

Acute causes:

- Ankle sprains — peroneal tendon injuries frequently occur alongside or are mistaken for lateral ankle sprains

- Forceful contraction of the peroneal muscles during sudden dorsiflexion (bending the foot upward), such as when landing from a jump or abruptly stopping — this is the classic mechanism for peroneal tendon subluxation

- Direct trauma to the lateral ankle

Overuse causes:

- Repetitive running, especially with a forefoot striking pattern

- Sudden increases in training volume or intensity

- Activities involving repetitive ankle motion on uneven terrain (hiking, trail running, court sports)

Anatomic risk factors:

- Varus (high-arched) hindfoot — this is the most well-established risk factor for peroneal tendinopathy. A high arch places the peroneal tendons under constant increased tension

- A flat or convex fibular groove — normally the groove behind the lateral malleolus is concave to cradle the tendons; a shallow or convex groove predisposes to subluxation

- Hypertrophy of the peroneal tubercle on the calcaneus

- An accessory peroneus quartus muscle (present in some individuals)

- A low-lying peroneus brevis muscle belly

- An os peroneum (an accessory bone within the peroneus longus tendon)

These anatomic variants are important because they can predispose to injury even without significant trauma and may influence surgical planning.

Symptoms of Peroneal Tendon Injuries

The hallmark symptom is pain on the outside of the ankle, behind or below the lateral malleolus. Specific symptoms vary by the type of injury:

Peroneal tendinopathy/tenosynovitis:

- Aching pain along the outer ankle that worsens with activity and improves with rest

- Swelling or fullness behind the lateral malleolus

- Pain with pushing off or turning the foot outward

- Tenderness when pressing along the tendon

- Crepitus (a grating sensation) with ankle motion

- A pattern similar to Achilles tendinopathy — pain that is worst when starting activity, improves with warm-up, and returns after prolonged use

Peroneal tendon tears:

- More severe or persistent lateral ankle pain

- Weakness when trying to evert (turn outward) the foot

- A feeling of ankle instability or "giving way"

- Pain that does not improve with standard ankle sprain treatment

Peroneal tendon subluxation/dislocation:

- A painful popping or snapping sensation on the outside of the ankle

- Visible snapping of the tendons over the lateral malleolus with ankle motion

- A feeling that something is "slipping" in the ankle

- Pain and swelling behind the lateral malleolus

Important: Because peroneal tendon injuries share many symptoms with ankle sprains, they are frequently missed. If you've been treated for an ankle sprain but your lateral ankle pain persists beyond 6 to 8 weeks — or if you have recurrent episodes of ankle instability — a peroneal tendon injury should be considered. This is one of the most common reasons for persistent pain after an ankle sprain.

How Are Peroneal Tendon Injuries Diagnosed?

Diagnosis begins with a thorough history and physical examination, which is the cornerstone of identifying peroneal tendon problems.

Physical examination:

- Standing assessment — the examiner looks for hindfoot varus (a high arch) and watches for visible peroneal tendon contractions while the patient balances on one foot

- Peroneal compression test — the examiner palpates along the fibular groove while the patient resists ankle plantar flexion and eversion. Pain during this maneuver is suggestive of peroneal tendinopathy

- Resisted eversion — testing strength of the peroneal muscles. Pain and weakness suggest tendon pathology

- Passive stretch test — pain with passive inversion and dorsiflexion stretches the peroneal tendons

- Subluxation test — circumduction (circular motion) of the ankle while palpating behind the lateral malleolus to feel for tendon snapping or subluxation

- Assessment for associated conditions — checking for ankle instability, stress fractures of the fifth metatarsal or lateral malleolus, and other causes of lateral ankle pain

Imaging:

- MRI is the standard imaging study for evaluating peroneal tendon disorders. High-resolution 1.5T or 3T MRI with dedicated extremity coils can accurately depict tendon tears, tenosynovitis, subluxation, and associated anatomic variants

- Ultrasound — high-resolution ultrasound with dynamic imaging is an excellent tool for evaluating the peroneal tendons. Its key advantage is the ability to perform real-time dynamic assessment — watching the tendons move during ankle motion to detect subluxation that may not be visible on static MRI

- X-rays — while they don't show the tendons directly, X-rays can reveal associated findings such as an os peroneum, avulsion fractures at the base of the fifth metatarsal, or a fleck sign (a small bone fragment indicating SPR avulsion)

Treatment for Peroneal Tendon Injuries

Treatment depends on the type and severity of the injury, the patient's activity level, and whether the condition is acute or chronic.

Conservative (Non-Surgical) Treatment

Most peroneal tendinopathies respond to non-surgical treatment:

- Activity modification — reducing or temporarily stopping activities that aggravate the pain. This does not mean complete rest — controlled, pain-guided activity is preferred

- Immobilization — a short period in a walking boot or ankle brace may be needed for acute flare-ups or tenosynovitis

- Physical therapy — the cornerstone of conservative treatment, focusing on:

  - Early range of motion exercises

  - Progressive tendon loading (gradually increasing the stress on the tendon to stimulate healing)

  - Proprioception and balance training

  - Peroneal strengthening — eversion exercises with resistance bands

  - Calf and ankle flexibility

- Orthotics — a lateral wedge under the heel or a recessed depression for the first metatarsal head can increase foot valgus and offload the peroneal tendons. This is especially important in patients with a varus (high-arched) hindfoot

- Bracing — an ankle brace or lace-up support can provide stability and reduce tendon stress during activity

- Anti-inflammatory measures — ice, NSAIDs, and occasionally a corticosteroid injection into the tendon sheath (not into the tendon itself) for acute tenosynovitis

Surgical Treatment

Surgery is indicated when conservative treatment fails (typically after 3 to 6 months) or for specific conditions that are unlikely to resolve without intervention:

For peroneal tendon tears:

The surgical approach depends on the extent of the tear:

- Tears involving less than 50% of the tendon — the damaged portion is excised and the tendon is repaired and tubularized (reshaped into a tube)

- Tears involving more than 50% of the tendon — tenodesis is performed, where the damaged tendon is attached to the adjacent healthy peroneal tendon

- Both tendons torn and unusable — tendon transfer (using the FDL or FHL tendon) or allograft reconstruction may be needed

For peroneal tendon subluxation/dislocation:

Surgery is often immediately indicated for recurrent symptomatic subluxation, as this condition rarely resolves with conservative treatment alone. Surgical options include:

- Repair or reconstruction of the superior peroneal retinaculum (SPR)

- Deepening of the fibular groove to create a better channel for the tendons

- Combined groove deepening with SPR repair — studies show excellent outcomes with this approach, with significant improvement in pain and function scores and return to normal gait

Outcomes of surgery:

Surgical treatment for peroneal tendon disorders generally produces good results. A systematic review of 336 patients found significant improvement in functional scores (AOFAS from 69.6 to 88.8) and pain scores (VAS from 4.7 to 1.2) after surgery. Return to activity within 12 weeks has been reported in 70–80% of patients following tenodesis.

Recovery After Peroneal Tendon Surgery

Recovery depends on the specific procedure performed and whether the superior peroneal retinaculum was repaired:

If the retinaculum was repaired:

- Weeks 1–2: Non-weight-bearing in a lower leg cast

- Weeks 3–6: Weight-bearing in a cast or walking boot

- Week 6: Begin active peroneal tendon exercises

- Months 2–3: Progressive strengthening and return to activity

If the retinaculum was not repaired:

- Early mobilization is encouraged

- Rehabilitation is guided by individualized, patient-directed goals rather than a strict time-based protocol

The median total immobilization period after peroneal tendon surgery is approximately 6 to 7 weeks, with a trend in recent literature toward shorter immobilization and earlier range of motion.

Peroneal Tendon Injuries in Athletes

Athletes are particularly susceptible to peroneal tendon problems due to the high demands placed on the lateral ankle:

- Runners — forefoot striking patterns increase stress on the peroneal tendons. Runners with a high-arched foot are at greatest risk

- Basketball, soccer, and volleyball players — repetitive jumping, cutting, and landing place the peroneal tendons at risk for both overuse injury and acute subluxation

- Trail runners and hikers — uneven terrain requires constant peroneal tendon activation for balance and stability

- Dancers — repetitive plantar flexion and inversion/eversion movements stress the peroneal tendons

For athletes, the key to successful treatment is accurate diagnosis — many athletes are treated for recurrent ankle sprains when the underlying problem is actually a peroneal tendon tear or subluxation. Addressing the correct diagnosis leads to targeted treatment and faster return to sport.

Athletes with peroneal tendon problems should also be evaluated for associated conditions including chronic ankle instability, stress fractures, and biomechanical issues such as calf tightness that may also contribute to plantar fasciitis and Achilles tendinopathy.

Prevention Tips

- Strengthen the peroneal muscles — resistance band eversion exercises build tendon resilience and improve lateral ankle stability

- Improve balance and proprioception — single-leg balance exercises, wobble board training, and sport-specific agility drills help prevent both peroneal injuries and ankle sprains

- Wear appropriate footwear — shoes with adequate lateral support and cushioning, especially for court sports and trail running

- Address hindfoot varus — if you have high arches, laterally posted orthotics can reduce chronic peroneal tendon overload

- Treat ankle sprains properly — complete rehabilitation after an ankle sprain, including peroneal strengthening, reduces the risk of developing chronic peroneal tendon problems

- Increase training gradually — avoid sudden spikes in running volume or intensity

Key Takeaways

- Peroneal tendon injuries are one of the most commonly missed diagnoses in foot and ankle medicine — only about 60% are correctly identified on the first evaluation

- They are frequently mistaken for or occur alongside ankle sprains

- The peroneus brevis is the more commonly injured tendon

- Varus (high-arched) hindfoot is the most important anatomic risk factor

- Most peroneal tendinopathies respond to conservative treatment with physical therapy, orthotics, and activity modification

- Surgery is indicated for tears, recurrent subluxation, or cases that fail conservative treatment — outcomes are generally excellent

- Accurate diagnosis is the most important step — if lateral ankle pain persists after ankle sprain treatment, a peroneal tendon injury should be considered

- Early evaluation leads to better outcomes and faster return to activity

Serving the North Texas Community

With offices in McKinney and Flower Mound, Dr. Sarang Desai provides expert diagnosis and treatment of peroneal tendon injuries and all foot and ankle conditions for patients across Allen, Frisco, Plano, Prosper, and the greater Dallas-Fort Worth area. If you've been dealing with persistent outer ankle pain, don't let a missed diagnosis keep you sidelined.

Book an Appointment | Call 972-591-6468