The peroneal tendons are two strong, cord-like structures that run along the outer side of the ankle and foot. They play a vital role in stabilizing the ankle and supporting movements such as turning the foot outward (eversion). Injuries to these tendons — including inflammation, tears, or dislocation — are a common but often overlooked cause of chronic ankle pain and instability. Early diagnosis and proper management are essential to prevent long-term weakness or deformity.
How Common It Is and Who Gets It? (Epidemiology)
Peroneal tendon injuries are commonly associated with ankle sprains, especially in athletes who engage in sports that involve cutting, jumping, or repetitive side-to-side motion such as soccer, basketball, skiing, and tennis. They may also occur in people with high arches, chronic ankle instability, or previous lateral ankle injuries.
Why It Happens – Causes (Etiology and Pathophysiology)
Peroneal tendon injuries can occur suddenly from trauma or develop gradually over time.
- Tendonitis: Repetitive motion, overuse, or acute twisting injuries cause inflammation.
- Tears: Repetitive friction or inversion injuries may split or rupture the tendon fibers, particularly the peroneus brevis, which lies close to the bone.
- Subluxation or dislocation: When the superior peroneal retinaculum (the stabilizing tissue over the tendons) tears, the tendons may slip out of their normal position behind the fibula.
- Predisposing factors: A shallow fibular groove or a low-lying muscle belly can increase susceptibility to injury.
How the Body Part Normally Works? (Relevant Anatomy)
The peroneus longus and peroneus brevis muscles originate from the outer side of the lower leg and travel behind the fibula in a narrow channel called the fibular groove. The superior peroneal retinaculum holds them in place.
- The peroneus brevis inserts on the base of the fifth metatarsal (outer midfoot).
- The peroneus longus runs under the foot to attach near the arch, providing stability to the foot during walking and balance.
These tendons act as dynamic stabilizers during ankle motion.
What You Might Feel – Symptoms (Clinical Presentation)
Symptoms depend on the type and severity of the injury:
- Pain and swelling along the outer side of the ankle
- A snapping or popping sensation behind the ankle bone
- Weakness when turning the foot outward (eversion)
- Instability or a feeling that the ankle may give way
- Difficulty with activities requiring balance or side-to-side movement
- In chronic cases, the pain may worsen with activity and improve with rest.
How Doctors Find the Problem? (Diagnosis and Imaging)
A foot and ankle specialist will perform a detailed examination, checking for pain, swelling, and snapping of the tendons during ankle movement.
- X-rays: Identify bone abnormalities or small avulsion fractures near the fibula.
- Ultrasound: Useful for dynamic evaluation of tendon subluxation or partial tears.
- MRI: Confirms the extent of tendon tears, inflammation, or displacement.
Classification
Peroneal tendon injuries are typically classified into three main categories:
- Tendonitis: Inflammation of the tendon sheath due to repetitive overuse or acute sprain.
- Tears:
- Acute tears from trauma or sudden twisting.
- Degenerative (chronic) tears due to prolonged strain, often associated with high arches.
- Subluxation: Displacement of the tendons from their normal position, either intermittently or continuously.
Other Problems That Can Feel Similar (Differential Diagnosis)
- Lateral ankle sprain
- Peroneal tendon dislocation or tear
- Fifth metatarsal stress fracture
- Chronic ankle instability
- Osteochondral lesion of the talus
- Subtalar joint arthritis.
Treatment Options
Non-Surgical Care
Most mild to moderate cases respond well to conservative care:
- Immobilization: A cast or boot may be used to allow the tendons to rest and heal.
- Medication: Anti-inflammatory drugs reduce swelling and pain.
- Physical therapy: Stretching, strengthening, and proprioceptive (balance) exercises aid recovery. Modalities such as ultrasound or ice may be used to relieve inflammation.
- Bracing: Supportive braces can prevent further strain during sports or daily activities.
These approaches are often effective for tendonitis or partial tears.
Surgical Care
Surgery is indicated when over 50% of a tendon is torn, symptoms persist despite therapy, or chronic subluxation causes ongoing pain.
Procedures include:
- Debridement and tubularization: Removal of damaged tissue and repair of remaining tendon fibers.
- Tenodesis (tendon transfer): If a tendon is beyond repair, the peroneus brevis may be attached to the peroneus longus to restore function.
- Retinaculum repair and groove deepening: The superior peroneal retinaculum is reconstructed, and the fibular groove is deepened to prevent tendon slippage.
Recovery and What to Expect After Treatment
After surgery, the ankle is immobilized in a splint or boot for 4–6 weeks.
- Non-weight-bearing: Crutches are used initially to protect the repair.
- Physical therapy: Gradual rehabilitation begins with range-of-motion and strengthening exercises.
- Return to activities: Most patients regain full function and strength within 3–4 months.
Following non-surgical care, recovery may be faster, though full healing still requires avoiding overuse.
Possible Risks or Side Effects (Complications)
- Recurrent tendon instability if the fibular groove is not adequately deepened
- Sural nerve irritation or numbness
- Persistent weakness or pain
- Postoperative stiffness if rehabilitation is delayed.
Long-Term Outlook (Prognosis)
The prognosis for peroneal tendon injuries is excellent when properly treated. Surgical repair or tendon transfer restores stability and strength, allowing most patients to return to athletic or daily activities without restrictions. Untreated cases may progress to chronic pain, weakness, or foot deformity.
Out-of-Pocket Costs
Medicare
CPT Code 27691 – Peroneus Brevis to Longus Tendon Transfer: $175.25
Medicare Part B covers 80% of the approved cost for this tendon transfer procedure once the annual deductible has been met. The remaining 20% is typically the patient’s responsibility; however, most people with Supplemental Insurance, such as Medigap, AARP, or Blue Cross Blue Shield, will have this portion covered as well. These supplemental policies are designed to work with Medicare, reducing or eliminating most out-of-pocket costs for Medicare-approved surgeries.
If you also have Secondary Insurance, such as an Employer-Based Plan, TRICARE, or Veterans Health Administration coverage, it will act as a secondary payer after Medicare. These plans often cover any remaining costs, such as deductibles or coinsurance, which usually range between $100 and $300 depending on your specific plan.
Workers’ Compensation
If your tendon transfer is necessary due to a work-related injury, Workers’ Compensation will cover all surgery, hospital, and rehabilitation costs associated with your treatment. You will have no out-of-pocket expense, as all payments are handled directly by the employer’s insurance carrier.
No-Fault Insurance
If your ankle or tendon injury occurred as the result of an automobile accident, No-Fault Insurance will pay for the entire cost of your procedure, including surgical and postoperative care. The only possible expense for you may be a small deductible or co-payment, depending on your insurance policy.
Example
Anthony Russo experienced chronic peroneal tendon pain and weakness following an ankle injury. He underwent a peroneus brevis to longus tendon transfer (CPT 27691) with an estimated Medicare out-of-pocket cost of $175.25. Because Anthony carried supplemental insurance through Blue Cross Blue Shield, his remaining balance was fully covered, leaving him with no out-of-pocket expenses.
Frequently Asked Questions (FAQ)
Q. What are peroneal tendon injuries?
A. Peroneal tendon injuries involve damage to the peroneal tendons on the outer side of the ankle, often resulting in pain, swelling, and difficulty with foot movement, especially with eversion (turning the foot outward).
Q. How is a peroneal tendon injury diagnosed?
A. Diagnosis typically involves a physical examination, medical history, and imaging tests such as MRI or ultrasound to assess the extent of tendon damage and confirm the diagnosis.
Q. What is the peroneus longus to brevis tendon transfer procedure?
A. This surgical procedure involves transferring the healthy peroneus longus tendon to replace the damaged peroneus brevis tendon to restore function and strength to the foot and ankle, particularly improving eversion.
Q. When is peroneus longus to brevis tendon transfer surgery necessary?
A. Surgery is usually necessary when more than 50% of the peroneus brevis tendon is damaged and conservative treatments like rest, physical therapy, or bracing do not provide sufficient relief.
Q. What are the benefits of the peroneus longus to brevis tendon transfer?
A. Benefits include restored strength, normal ankle function, improved range of motion, and enhanced clinical outcomes, such as pain relief and better functional scores.
Q. What is the recovery time after peroneus longus to brevis tendon transfer?
A. Recovery includes immobilization for a few weeks, followed by crutches for 4 to 6 weeks. Full recovery may take several months, with physical therapy helping to restore function and strength.
Q. What are the risks of peroneus longus to brevis tendon transfer surgery?
A. Risks include infection, nerve injury, tendon failure, and complications related to the surgical site, though these are relatively rare and can be managed with proper care.
Q. How effective is the peroneus longus to brevis tendon transfer procedure?
A. The procedure is highly effective, with patients experiencing restored ankle function, improved strength, and a reduction in pain, with many returning to normal activities after recovery.
Q. Can peroneal tendon injuries be treated without surgery?
A. Yes, mild to moderate peroneal tendon injuries can often be treated conservatively with rest, ice, anti-inflammatory medications, physical therapy, and the use of supportive footwear or ankle braces. Surgery is typically reserved for more severe cases.
Q. What are the symptoms of a peroneal tendon injury?
A. Symptoms include pain on the outer side of the ankle, swelling, bruising, weakness in the ankle, instability, and difficulty with activities involving foot movement, especially when turning the foot outward.
Q. How is peroneal tendon damage prevented?
A. Preventative measures include strengthening the ankle and foot muscles, using proper footwear, avoiding excessive strain on the tendons, and practicing balance exercises to improve stability and reduce the risk of injury.
Q. Will I be able to return to sports after a peroneal tendon injury?
A. Most patients can return to sports after recovery, although the timeline depends on the severity of the injury and how well the tendon heals. Full recovery may take several months, and high-impact activities should be avoided until healing is complete.
Q. What are the long-term effects of untreated peroneal tendon injuries?
A. If left untreated, peroneal tendon injuries can lead to chronic pain, ankle instability, increased risk of recurrent injuries, and, in severe cases, tendon rupture or permanent loss of function in the ankle.
Q. Can peroneal tendon injuries occur in both tendons at the same time?
A. Yes, it is possible for both the peroneus longus and peroneus brevis tendons to be injured simultaneously, which can result in more significant ankle instability and functional limitations.
Q. Is peroneal tendon surgery effective for everyone?
A. While peroneal tendon surgery is effective for most patients, its success depends on factors such as the extent of the tendon damage, the patient’s overall health, and adherence to post-surgical rehabilitation.
Q. Can peroneal tendon injuries lead to other foot or ankle conditions?
A. Yes, untreated or chronic peroneal tendon injuries can lead to other issues such as flatfoot, lateral ankle instability, and the development of secondary conditions like tendonitis or arthritis due to compensatory mechanics.
Q. What are the peroneal tendons?
A. They are two tendons on the outer side of the ankle that stabilize the foot and help it turn outward.
Q. Can peroneal tendon injuries heal without surgery?
A. Yes, mild cases of tendonitis or partial tears can heal with rest, bracing, and therapy.
Q. What is a peroneus brevis-to-longus tendon transfer?
A. This is a surgical procedure where a damaged peroneus brevis tendon is replaced with the peroneus longus to restore normal ankle function.
Q. How long is recovery after surgery?
A. Most patients regain strength and mobility within 3–4 months following a structured rehabilitation plan.
Q. Can I return to sports?
A. Yes. Once strength, balance, and motion are fully restored, patients can return to athletic activity under their surgeon’s guidance.
Summary and Takeaway
Peroneal tendon injuries — including tendonitis, tears, and subluxations — are a common source of chronic lateral ankle pain. Early recognition and proper management lead to excellent recovery. For severe tendon damage, surgical options such as peroneus brevis-to-longus tendon transfer effectively restore function and stability, allowing patients to return to pain-free activity.
Clinical Insight & Recent Findings
A recent study reviewed three cases of peroneal tendon injury to highlight diagnosis and surgical outcomes. The study found that these injuries, often mistaken for ankle sprains, can cause chronic pain and instability if untreated.
All patients underwent open peroneal tendon repair—two with groove deepening and one with tendon tubularization—and achieved significant improvement in ankle stability and function within 12 to 24 weeks, without complications.
The report emphasized that surgical repair is highly effective when conservative treatment fails, restoring strength and mobility while preventing long-term pain or gait impairment. (“Study on peroneal tendon injury – see PubMed.“)
Who Performs This Treatment? (Specialists and Team Involved)
Peroneal tendon injuries are treated by orthopedic foot and ankle surgeons or podiatric surgeons. Physical therapists and sports medicine specialists are essential for rehabilitation, helping restore ankle strength and proprioception.
When to See a Specialist?
You should see a specialist if you experience persistent pain, swelling, snapping, or weakness along the outer side of your ankle that does not improve with rest.
When to Go to the Emergency Room?
Seek immediate care if you have severe ankle pain after a twisting injury, inability to walk, or visible tendon displacement behind the ankle bone.
What Recovery Really Looks Like?
Recovery may involve several weeks of rest followed by physical therapy. Most patients use crutches or a walking boot initially and gradually progress to full weight-bearing. Strengthening and proprioception training are crucial for returning to normal function.
What Happens If You Ignore It?
Ignoring peroneal tendon injuries can lead to chronic instability, tendon rupture, or arch deformity. Prolonged symptoms can result in irreversible tendon degeneration and functional weakness.
How to Prevent It?
- Wear supportive footwear during sports and exercise
- Avoid repetitive ankle strain or overuse
- Strengthen ankle and calf muscles
- Use proper warm-up and stretching before activity
- Address any recurrent ankle instability early.
Nutrition and Bone or Joint Health
Adequate protein, vitamin D, and calcium intake support tendon and bone health. Omega-3 fatty acids and antioxidants help reduce inflammation and promote healing.
Activity and Lifestyle Modifications
After recovery, resume activities gradually. Choose low-impact exercises like cycling or swimming until full strength returns. Use ankle supports or braces during high-risk sports to reduce the risk of re-injury.
Dr. Mo Athar
