Peroneal tendons

Function

Where the two tendons run

A tendon is a tough cord of tissue that connects a muscle to a bone. The peroneal tendons belong to the peroneus longus and peroneus brevis, also called the fibularis longus and brevis². These two muscles on the outer side of the leg point the foot down and turn the sole outward⁵.

The peroneus longus becomes fully tendon about 3 to 4 cm above the lower end of the fibula¹. The peroneus brevis muscle reaches lower, into the groove behind the lateral malleolus, the bony bump on the outer side of the ankle¹.

The outer surface of the calcaneus (heel bone) carries a ridge called the peroneal tubercle⁶. A metatarsal is one of the long bones in the middle of the foot. The two tendons take different paths past these landmarks²:

Where	Peroneus brevis tendon	Peroneus longus tendon
Behind the lower end of the fibula	Fairly flat, right against the bone2	Rounder, behind the brevis tendon2
On the heel bone	Above the peroneal tubercle2	Below the peroneal tubercle2
Where it ends	Base of the fifth metatarsal7	Base of the first metatarsal and a bone called the medial cuneiform7

Around the ankle, the two tendons share one synovial sheath, a fluid-lined sleeve that a tendon glides in². It runs from about 4 cm above the tip of the lateral malleolus to about 1 cm below it². Lower down, the tendons part into two sheaths and cross the outer wall of the heel bone².

The longus tendon then passes under the cuboid bone and crosses the sole at a slant². Its tunnel there is formed by a groove in the cuboid and the long plantar ligament². A small extra bone, the os peroneum, can sit inside the far end of the longus tendon where it enters this tunnel¹. Estimates of how often it is present range from 4 to 30%¹.

What holds the tendons in place

At the tip of the fibula, both tendons run through a tunnel of bone and fibrous tissue¹. A retinaculum is a band of tissue that holds tendons in place where they cross a joint. The peroneal retinaculum has an upper and a lower band².

Both typically start on the lowest 2 cm of the fibula². The upper band reaches the Achilles tendon and the lower band the outer side of the heel bone². The upper band is the main restraint that keeps the tendons from slipping out of place².

The shape of the groove behind the fibula is set mainly by a thick cushion of fibrocartilage, a tough, fibrous kind of cartilage⁸. The bone itself matters less⁸. Two studies sorted the groove by shape, and their figures differ. One used cadavers (bodies donated for study) and one MRI (magnetic resonance imaging)^2,9:

Groove shape	178 cadaver fibulae	MRI of 65 volunteers with symptom-free ankles
Concave	82%2	28%9
Flat	11%2	43%9
Convex	7%2	18%9

The MRI study classed the remaining 11% of grooves as irregular⁹.

What the tendons do

The peroneal tendons are the foot’s primary evertors, and they steady the outer side of the ankle². Sources differ on which tendon does more^2,10:

• A narrative review, a summary of research written without a set search method, credits the peroneus brevis with 63% of total eversion power².
• Six cadaver feet were tested in a simulated early heel rise¹¹. Loading the brevis tendon tilted the heel bone 0.9 degrees further outward than the same load on the longus tendon¹¹.
• A review of the subtalar joint, the joint just below the ankle joint, names the peroneus longus as the strongest evertor crossing it¹⁰.

The peroneus longus also steadies the inner column of the foot in stance, when the foot is on the ground². In ten cadaver feet, a force pushed the first metatarsal inward¹². The bone shifted significantly only after the longus tendon was cut¹².

How blood reaches the tendons

In ten fresh-frozen cadavers, the tendons got their blood mainly from the peroneal artery¹³. It arrived through a band of tissue on the back-outer side that connects both tendons¹³. Whether the tendons have avascular zones, meaning areas without blood vessels, at the sites where they most often tear is disputed¹³. Three studies that injected the vessels reached different answers^13,14,15:

Whether the tendons have avascular zones, meaning areas without blood vessels, at the sites where they most often tear is disputed.

• One reported that the brevis tendon is almost avascular in the fibular groove, where it is squeezed between the longus tendon and bone¹⁴.
• One, of ten cadaver specimens, found no avascular zones in the brevis tendon and zones with a poor blood supply in eight longus tendons¹³.
• One, of 22 cadaver lower limbs, found avascular areas in the brevis tendon in 22.7% and in no longus tendon¹⁵.

Breakdown

Three kinds of problem

A consensus panel, a group of experts who meet to agree a shared view, sorted peroneal tendon problems into three categories¹:

• tendinopathy, meaning local pain in a tendon that comes with activities that load it¹;
• tear or rupture¹;
• instability or dislocation¹.

In the panel’s terms, a “tear” usually means a lengthwise tear or an incomplete rupture¹. A “rupture” means the tendon is completely separated¹. A narrative review states that tears may be acute (recent), but most are chronic (long-lasting)¹⁶. In peroneal tendinosis the tendon thickens and swells, with patches of degeneration, more often below the outer ankle bone².

How common tears are

How common peroneal tendon tears are in the general population is unknown¹. Cadaver studies have found tears in 11 to 38% of ankles¹. In one dissection of 124 cadaver ankles, the brevis tendon was worn in 14 (11.3%) and the longus tendon in none¹⁷.

How common peroneal tendon tears are in the general population is unknown.

Scans can show changes without symptoms. In 170 people with no peroneal symptoms, ultrasound showed abnormalities in 20% of longus tendons and 12% of brevis tendons¹⁸.

Which tendon tears, and where

One series covered 234 patients in a row who had surgery for long-lasting, symptomatic tears³:

Tendon torn	Share of tears
Peroneus brevis only	73%3
Peroneus longus only	8%3
Both tendons	19%3

A narrative review describes the usual brevis tear as lengthwise and centred at the tip of the fibula¹⁶. There the tendon turns sharply and is compressed between the longus tendon and the fibula¹⁶. In a cadaver dissection study, brevis splits averaged 1.9 cm long, and none was a complete rupture¹⁷. The same review states that longus tears are much less common¹⁶. Most sit between the peroneal tubercle and the cuboid tunnel¹⁶.

What goes with tears

Studies and a consensus statement link tears with several factors^1,3:

• Foot shape. The 234 patients were compared with matched controls³. A high-arched, inward-tilted foot shape, called cavovarus, had a statistically significant association with tears³.
• A crowded tunnel. A consensus statement names overfilling of the tunnel as an important factor in peroneal tendon problems, more so than the groove’s shape¹.
• Ankle instability. Sixty-one patients had a first ligament reconstruction for chronic outer-ankle instability, and 25% had a brevis tear¹⁹.
• An earlier sprain. Eighteen patients had surgery for brevis splits with chronic ankle instability²⁰. On average, six years passed between the ankle sprain and pain behind the outer ankle²⁰.

In Swedish register data on 719 patients having first-time peroneal tendon surgery, patients averaged 49 years of age at surgery²³. Brevis rupture and tendinosis were more prevalent in women than in men²³.

How the tendons slip out of place

Peroneal tendon dislocation occurs in 0.3 to 0.5% of all traumatic ankle events⁴. An acute dislocation typically follows a forced eccentric contraction, with the ankle in dorsiflexion and eversion¹. Eccentric means the peroneal muscles work while they lengthen, and dorsiflexion means pulling the foot up toward the shin. The upper retinaculum can then rupture, letting the tendons dislocate forward over the outer ankle bone⁴. Dislocation is most prevalent in athletes, mainly in sports with cutting movements such as skiing, soccer, basketball, ice skating and gymnastics⁴.

One study compared scans of 30 patients with repeated dislocation and 30 matched controls²⁴. A low-lying brevis muscle belly, the thick middle part of the muscle, was significantly associated with dislocation²⁴. The bony shape of the groove was not²⁴.

Recovery

How well tears heal

Peroneal tendon tears are described as seeming to have a poor tendency to heal¹³. The consensus panel agreed that acute injuries have a better healing tendency than chronic ones¹. Its statement notes that evidence on outcomes without surgery in acute peroneal tendinopathy is limited and varied¹.

What studies of tear surgery found

• A systematic review of nine studies, with 336 patients, found an average overall complication rate of 38.7%²⁵. Ankle pain was the most commonly reported minor complication²⁵.
• Forty-one patients were followed for at least 1 year after surgery for 49 tears²⁶. Their average return to activity took 3.49 months, and 14 of the 16 athletes got back to full sporting level²⁶.
• The consensus statement notes that elite athletes may not get back to their earlier level of sport after surgery for a rupture¹.

What studies of dislocation found

A consensus statement reports that evidence on dislocation managed without surgery is limited to case reports and small series¹. These suggest a risk of repeated peroneal instability of about 50%¹.

A systematic review of 14 studies of surgery found return-to-sport rates of 83 to 100% in the two surgical groups it analysed⁴. The redislocation rate in those groups was below 1.5%⁴. All 14 studies were scored as low quality, and none had a control group, randomisation or masked assessment⁴.

Connections

The muscles and bones around them

The peroneal muscles share the lateral compartment of the leg with the common fibular nerve and the superficial fibular nerve²⁷. Below the fibula, on the calcaneus, the peroneal tubercle separates an upper groove for the brevis tendon from a lower one for the longus⁶. The brevis tendon ends on the fifth of the metatarsals and is consistently present²⁸.

The ligaments beside them

The tendons and their sheaths cross over the calcaneofibular ligament, one of the lateral ankle ligaments²⁹. Only about 1 cm of that ligament is left uncovered²⁹. Slipping of the peroneal tendons is commonly associated with lengthwise brevis splits and with outer-ankle instability⁸. Disrupted lateral ankle ligaments put considerable strain on the upper retinaculum⁸.

Running

Related exercise pages: running. One study recorded muscle activity with fine-wire electrodes, thin wire sensors placed into a muscle, in 15 injury-free recreational and competitive runners³⁰. Across three paces, peroneus brevis activity rose significantly as pace increased³⁰.

Sources

1. van Dijk PA, Miller D, Calder J, DiGiovanni CW, Kennedy JG, Kerkhoffs GM, Kynsburg A, Haverkamp D, Guillo S, Oliva XM, Pearce CJ, Pereira H, Spennacchio P, Stephen JM, van Dijk CN (2018). The ESSKA-AFAS international consensus statement on peroneal tendon pathologies. Knee Surgery, Sports Traumatology, Arthroscopy. doi:10.1007/s00167-018-4971-x PMID 29767272
2. Davda K, Malhotra K, O'Donnell P, Singh D, Cullen N (2017). Peroneal tendon disorders. EFORT Open Reviews. doi:10.1302/2058-5241.2.160047 PMID 28736620
3. Taniguchi A, Alejandro SF, Kane JM, Daoud Y, Tanaka Y, Ford SE, Brodsky JW (2021). Association of Cavovarus Foot Alignment With Peroneal Tendon Tears. Foot & Ankle International. doi:10.1177/1071100721990348 PMID 33847151
4. van Dijk PA, Gianakos AL, Kerkhoffs GM, Kennedy JG (2016). Return to sports and clinical outcomes in patients treated for peroneal tendon dislocation: a systematic review. Knee Surgery, Sports Traumatology, Arthroscopy. doi:10.1007/s00167-015-3833-z PMID 26519186
5. Brockett CL, Chapman GJ (2016). Biomechanics of the ankle.. Orthopaedics and Trauma. doi:10.1016/j.mporth.2016.04.015 PMID 27594929
6. Gray H; Lewis WH (editor) (1918). Anatomy of the Human Body. Lea & Febiger, Philadelphia (20th edition). Link
7. Walt J, Massey P (2023). Peroneal Tendon Syndromes. StatPearls. PMID 31335074
8. Ferran NA, Oliva F, Maffulli N (2006). Recurrent subluxation of the peroneal tendons. Sports Medicine. doi:10.2165/00007256-200636100-00003 PMID 17004847
9. Saupe N, Mengiardi B, Pfirrmann CW, Vienne P, Seifert B, Zanetti M (2007). Anatomic variants associated with peroneal tendon disorders: MR imaging findings in volunteers with asymptomatic ankles. Radiology. doi:10.1148/radiol.2422051993 PMID 17255421
10. Krähenbühl N, Horn-Lang T, Hintermann B, Knupp M (2017). The subtalar joint: A complex mechanism. EFORT open reviews. doi:10.1302/2058-5241.2.160050 PMID 28828179
11. Otis JC, Deland JT, Lee S, Gordon J (2004). Peroneus brevis is a more effective evertor than peroneus longus. Foot & Ankle International. doi:10.1177/107110070402500408 PMID 15132932
12. Bohne WH, Lee KT, Peterson MG (1997). Action of the peroneus longus tendon on the first metatarsal against metatarsus primus varus force. Foot & Ankle International. doi:10.1177/107110079701800810 PMID 9278747
13. van Dijk PA, Madirolas FX, Carrera A, Kerkhoffs GM, Reina F (2016). Peroneal tendons well vascularized: results from a cadaveric study. Knee Surgery, Sports Traumatology, Arthroscopy. doi:10.1007/s00167-015-3946-4 PMID 26740089
14. Petersen W, Bobka T, Stein V, Tillmann B (2000). Blood supply of the peroneal tendons: injection and immunohistochemical studies of cadaver tendons. Acta Orthopaedica Scandinavica. doi:10.1080/000164700317413148 PMID 10852323
15. Mota Gomes T, Guerra-Pinto F, Soares S, Andrade R, Pereira B, Espregueira-Mendes J, Oliva XM (2021). The vascularization of the peroneal tendons: An anatomic study. Foot and Ankle Surgery. doi:10.1016/j.fas.2020.06.004 PMID 32600968
16. Danna NR, Brodsky JW (2020). Diagnosis and Operative Treatment of Peroneal Tendon Tears. Foot & Ankle Orthopaedics. doi:10.1177/2473011420910407 PMID 35097372
17. Sobel M, Bohne WH, Levy ME (1990). Longitudinal attrition of the peroneus brevis tendon in the fibular groove: an anatomic study. Foot & Ankle. doi:10.1177/107110079001100302 PMID 2131804
18. Smoker BA, Giakas AM, Mills FB 4th, Williams KA, Bornemann PH, Jackson JB 3rd (2023). Prevalence of Abnormal Ultrasonographic Findings in Asymptomatic Peroneal Tendons. Foot & Ankle Orthopaedics. doi:10.1177/24730114231164146 PMID 37009419
19. DiGiovanni BF, Fraga CJ, Cohen BE, Shereff MJ (2000). Associated injuries found in chronic lateral ankle instability. Foot & Ankle International. doi:10.1177/107110070002101003 PMID 11128010
20. Bonnin M, Tavernier T, Bouysset M (1997). Split lesions of the peroneus brevis tendon in chronic ankle laxity. The American Journal of Sports Medicine. doi:10.1177/036354659702500520 PMID 9302480
21. Ziai P, Benca E, Wenzel F, Schuh R, Krall C, Auffahrt A, Hofstetter M, Windhager R, Buchhorn T (2016). Peroneal tendinosis as a predisposing factor for the acute lateral ankle sprain in runners. Knee Surgery, Sports Traumatology, Arthroscopy. doi:10.1007/s00167-015-3562-3 PMID 25786820
22. Ritter S, Moore M (2008). The relationship between lateral ankle sprain and ankle tendinitis in ballet dancers. Journal of Dance Medicine & Science. PMID 19618575
23. André F, Cöster M, Carling M, Pellnor J, Gunnarsson B, Helander KN (2026). A demographic and descriptive analysis of patients who underwent peroneal tendon surgery: Data from the Swedish Foot and Ankle Register (Swefoot). Foot (Edinburgh). doi:10.1016/j.foot.2026.102249 PMID 41887048
24. Nishimura A, Nakazora S, Senga Y, Fukuda A, Sudo A (2023). Anatomic Features of Patients With Recurrent Peroneal Tendon Dislocation. The American Journal of Sports Medicine. doi:10.1177/03635465231158100 PMID 36876737
25. Mercer NP, Gianakos AL, Mercurio AM, Kennedy JG (2021). Clinical Outcomes of Peroneal Tendon Tears: A Systematic Review. The Journal of Foot and Ankle Surgery. doi:10.1053/j.jfas.2021.03.003 PMID 33785239
26. Saxena A, Cassidy A (2003). Peroneal tendon injuries: an evaluation of 49 tears in 41 patients. The Journal of Foot and Ankle Surgery. doi:10.1016/s1067-2516(03)70031-3 PMID 12907932
27. Khan IA, Mahabadi N, D'Abarno A, Varacallo MA (2023). Anatomy, Bony Pelvis and Lower Limb: Leg Lateral Compartment.. StatPearls. PMID 30137811
28. Liu X, Hong CC, Reina F, Carrera A, Alcolea-Madera E, Del Vecchio JJ, Dalmau-Pastor M (2026). Navicular and fifth metatarsal base stress fractures: An illustrated anatomical review. Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA. doi:10.1002/ksa.70413 PMID 42171011
29. Golanó P, Vega J, de Leeuw PA, Malagelada F, Manzanares MC, Götzens V, van Dijk CN (2010). Anatomy of the ankle ligaments: a pictorial essay.. Knee Surgery, Sports Traumatology, Arthroscopy. doi:10.1007/s00167-010-1100-x PMID 20309522
30. Reber L, Perry J, Pink M (1993). Muscular control of the ankle in running.. The American journal of sports medicine. doi:10.1177/036354659302100608 PMID 8291630

Every source the library cites

Changes

• October 5, 2026 First published.