Peroneus Brevis – Anatomy, Nerve Supply, Functions

Last updated: February 8, 2026Reviewed date: February 8, 2026Reading time: 3 min read
Patient Tools

Read, save, and share this guide

Use these quick tools to make this medical article easier to read, print, save, or share with a family member.

Patient Mode

Understand this article easily

Switch between simple English and easy Bangla patient notes. This is for education and does not replace a doctor consultation.

Peroneus Brevis muscle also referred to as the fibularis brevis muscle, is located in the lateral compartment of the lower extremity below the knee, underneath the peroneus longus muscle. It is a small, relatively short muscle of the leg that originates from the lower two-thirds...

For severe symptoms, danger signs, pregnancy, child illness, or sudden worsening, seek urgent medical care.

বাংলা রোগী নোট এখনো যোগ করা হয়নি। পোস্ট এডিটরে “RX Bangla Patient Mode” বক্স থেকে সহজ বাংলা সারাংশ যোগ করুন।

এই তথ্য শিক্ষা ও সচেতনতার জন্য। এটি ডাক্তারি পরীক্ষা, রোগ নির্ণয় বা প্রেসক্রিপশনের বিকল্প নয়।

Article Summary

Peroneus Brevis muscle also referred to as the fibularis brevis muscle, is located in the lateral compartment of the lower extremity below the knee, underneath the peroneus longus muscle. It is a small, relatively short muscle of the leg that originates from the lower two-thirds of the lateral surface of the fibula bone. Its muscle fibers traverse downwards and form into a tendon which runs...

Key Takeaways

  • This article explains Anatomy of Peroneus Brevis in simple medical language.
  • This article explains Blood Supply of Peroneus Brevis in simple medical language.
  • This article explains Nerves of Peroneus Brevis in simple medical language.
  • This article explains Functions of Peroneus Brevis in simple medical language.
Educational health guideWritten for patient understanding and clinical awareness.
Reviewed content workflowUse writer and reviewer profiles for stronger trust.
Emergency safety firstUrgent warning signs are highlighted below.

Seek urgent medical care if you notice

These warning signs are general safety guidance. Local emergency numbers and clinical judgment should always come first.

  • Severe symptoms, breathing difficulty, fainting, confusion, or rapidly worsening illness.
  • New weakness, severe pain, high fever, or symptoms after a serious injury.
  • Any symptom that feels urgent, unusual, or unsafe for the patient.
1

Emergency now

Use emergency care for severe, sudden, rapidly worsening, or life-threatening symptoms.

2

See a doctor

Book a professional medical evaluation if symptoms persist, worsen, recur often, affect daily activities, or occur in a high-risk patient.

3

Learn safely

Use this article to understand possible causes, tests, treatment options, prevention, and questions to ask your clinician.

Before reading

RX Patient Tools

Use these quick guides before reading the article, or return to them when you need help preparing questions for a doctor.

Start here Choose the right pathway for symptoms, reports, medicines, or urgent warning signs. Disease article roadmap Read this topic step by step: meaning, symptoms, warning signs, diagnosis, treatment, prevention, and follow-up. Treatment planner Prepare questions about treatment choices, benefits, risks, side effects, and follow-up. Family & caregiver guide Organize symptoms, reports, medicines, questions, and follow-up safely. Nutrition & diet guide Prepare food, hydration, supplement, and medicine-timing questions safely. Prevention guide Organize risk factors, protective habits, screening, and warning signs. Recovery guide Prepare a safe plan for activity, rehabilitation, warning signs, and follow-up.
Definition

Peroneus Brevis muscle also referred to as the fibularis brevis muscle, is located in the lateral compartment of the lower extremity below the knee, underneath the peroneus longus muscle. It is a small, relatively short muscle of the leg that originates from the lower two-thirds of the lateral surface of the fibula bone. Its muscle fibers traverse downwards and form into a tendon which runs just posterior to the lateral malleolus, crossing the ankle, and inserting on the styloid process of the proximal the fifth metatarsal bone.

The peroneus brevis muscle, also known as the fibularis brevis muscle, is a muscle in the lateral compartment of the leg. It lies deep/medial to the adjacent peroneus longus, and is a shorter and smaller muscle. Both brevis and longus travel together along the lateral aspect of the ankle within a shared synovial sheath 4. Together the tendons wrap around the lateral malleolus, specifically within the trimalleolar groove of the distal fibula.

Anatomy of Peroneus Brevis

  • The peroneus brevis is another of the three muscles spanning the lateral leg and may also be called fibularis brevis, referring to the fibula
  • Origin: The peroneus brevis originates on the inferior two-thirds of the lateral fibula and courses posteriorly to the lateral malleolus of the fibula ultimately
  • Insertion: The styloid process of the fifth metatarsal
  • Action: The primary action of the peroneus brevis is to evert the foot and plantar flex the ankle
  • Blood Supply: Peroneal artery
  • Innervation: The superficial peroneal nerve innervates the peroneus brevis muscle

Blood Supply of Peroneus Brevis

Fibularis brevis and the other muscles of the lateral compartment of the leg are supplied by the superior and inferior branches of the anterior tibial artery. This is a branch of the popliteal artery, which is the distal continuation of the femoral artery. On rare occasions, the chief blood supply to the lateral compartment is the fibular artery, which is a branch of the tibial artery.

The tendon of fibularis brevis and its accompanying muscle is supplied by an anastomotic network around the ankle. The network includes the arcuate, anterior lateral malleolar, fibular perforating, lateral calcaneal, lateral and medial plantar and lateral tarsal arteries. The venous blood from this muscle is conveyed by the anterior tibial vein.

Nerves of Peroneus Brevis

  • The peroneus brevis receives its innervation from the muscular branch of the superficial peroneal nerve (L5-S2). The superficial peroneal nerve courses around the proximal fibula, where it is prone to injury.

Functions of Peroneus Brevis

  • The primary movements of the foot and ankle are plantar flexion, dorsiflexion, eversion, and inversion. The peroneal brevis muscle and tendon cross the ankle joint posterior to the fibula. The peroneus brevis muscle assists with eversion of the foot, and to a weaker extent, plantarflexes the ankle.
  • The muscle assists in weak plantarflexion and eversion of the foot.

or

  • Fibularis Brevis crosses both the subtalar (talocalcaneal) and talocrural (ankle) joints and therefore contributes to the actions produced across these joints. The main function of fibularis brevis is to evert the foot at the subtalar joint, which helps to restore the foot to its anatomical position after it has been inverted. This is particularly important when running or walking on uneven terrain.
  • Since fibularis brevis counteracts inversion of the foot, it may also prevent the body from falling to the opposite side when the individual is balancing on one leg. The muscle also causes

References

Doctor visit helper

Prepare before seeing a doctor

A simple rural-patient checklist to help you explain symptoms clearly, ask better questions, and avoid unsafe self-treatment.

Safety note: This is not a prescription or diagnosis. For severe symptoms, pregnancy danger signs, children with serious illness, chest pain, breathing difficulty, stroke-like weakness, or major injury, seek urgent care.

Which doctor may help?

Start with a registered doctor or the nearest qualified health center.

What to tell the doctor

  • Write when the problem started and how it changed.
  • Bring old prescriptions, investigation reports, and current medicines.
  • Write allergies, pregnancy status, diabetes, kidney/liver disease, and major past illnesses.
  • Bring one family member if the patient is weak, elderly, confused, or a child.

Questions to ask

  • What is the most likely cause of my symptoms?
  • Which danger signs mean I should go to hospital quickly?
  • Which tests are necessary now, and which can wait?
  • How should I take medicines safely and what side effects should I watch for?
  • When should I come for follow-up?

Tests to discuss

  • Vital signs: temperature, pulse, blood pressure, oxygen saturation
  • Basic physical examination by a clinician
  • CBC, urine test, blood sugar, or imaging only when clinically needed

Avoid these mistakes

  • Do not use antibiotics, steroid tablets/injections, or strong painkillers without proper medical advice.
  • Do not hide pregnancy, kidney disease, ulcer, allergy, or blood thinner use.
  • Do not delay emergency care when danger signs are present.

Medicine safety and first-aid guide

This section is for patient education only. It does not replace a doctor, pharmacist, or emergency care.

Safe first steps

  • Rest, drink safe water, and observe symptoms carefully.
  • Keep a written note of symptoms, duration, temperature, medicines already taken, and allergy history.
  • Seek medical care quickly if symptoms are severe, worsening, or unusual for the patient.

OTC medicine safety

  • For mild pain or fever, ask a registered pharmacist or doctor before using common over-the-counter pain/fever medicines.
  • Do not combine multiple pain medicines without advice, especially if you have kidney disease, liver disease, stomach ulcer, asthma, pregnancy, or take blood thinners.
  • Do not give adult medicines to children unless a qualified clinician advises it.

Avoid these mistakes

  • Do not start antibiotics without a proper medical decision.
  • Do not use steroid tablets or injections casually for quick relief.
  • Do not delay emergency care because of home remedies.

Get urgent help if

  • Severe symptoms, confusion, fainting, breathing difficulty, chest pain, severe dehydration, or sudden weakness need urgent medical care.
Medicine names, dose, and timing must be decided by a qualified clinician or pharmacist after checking age, pregnancy, allergy, other diseases, and current medicines.

For rural patients and family caregivers

Patient health record and symptom diary

Write your symptoms, medicines already taken, test results, and questions before visiting a doctor. This note stays on your device unless you print or copy it.

Doctor to discuss: Doctor / qualified healthcare provider
Tests to discuss with doctor
  • Basic vital signs: temperature, pulse, blood pressure, oxygen level if needed
  • Relevant blood, urine, imaging, or specialist tests only after clinical assessment
Questions to ask
  • What is the most likely cause of my symptoms?
  • Which warning signs mean I should go to emergency care?
  • Which tests are really needed now?
  • Which medicines are safe for my age, pregnancy status, allergy, kidney/liver/stomach condition, and current medicines?

Emergency warning signs such as chest pain, severe breathing difficulty, sudden weakness, confusion, severe dehydration, major injury, or loss of bladder/bowel control need urgent medical care. Do not wait for online information.

Safe pathway to proper treatment

Care roadmap for: Peroneus Brevis – Anatomy, Nerve Supply, Functions

Use this simple roadmap to understand the next safe steps. It is educational and does not replace examination by a doctor.

Go to emergency care if you notice:
  • Severe or rapidly worsening symptoms
  • Breathing difficulty, chest pain, fainting, confusion, severe weakness, major injury, or severe dehydration
Doctor / service to discuss: Qualified healthcare provider; specialist depends on symptoms and examination.
  1. Step 1

    Check danger signs first

    If danger signs are present, seek emergency care and do not wait for online information.

  2. Step 2

    Record the symptom story

    Write when symptoms started, severity, medicines already taken, allergies, pregnancy status, and test results.

  3. Step 3

    Visit a qualified clinician

    A doctor, nurse, or qualified healthcare provider can examine you and decide which tests or treatment are needed.

  4. Step 4

    Do only useful tests

    Do tests after clinical assessment. Avoid unnecessary tests, random antibiotics, or repeated medicines without diagnosis.

  5. Step 5

    Follow up and return early if worse

    If symptoms worsen, new warning signs appear, or treatment is not helping, return for review quickly.

Rural patient practical tips
  • Take a written symptom diary and all previous prescriptions/test reports.
  • Do not hide medicines already taken, even herbal or over-the-counter medicines.
  • Ask which warning signs mean urgent referral to hospital.

This roadmap is for education. A real diagnosis and treatment plan requires history, examination, and clinical judgment.

RX Patient Help

Ask a health question safely

Write your symptom story. A health professional or site editor can review it before any answer is prepared. This box is not for emergency care.

Emergency first: Severe chest pain, breathing trouble, unconsciousness, stroke signs, severe injury, heavy bleeding, or rapidly worsening symptoms need urgent local medical care now.

Frequently Asked Questions

Is this article a replacement for a doctor?

No. It is educational content only. Patients should consult a qualified clinician for diagnosis and treatment.

When should I seek urgent care?

Seek urgent care for severe symptoms, rapidly worsening condition, breathing difficulty, severe pain, neurological changes, or any emergency warning sign.

References

Add references, clinical guidelines, textbooks, journal articles, or trusted medical sources here. You can edit this area from the RX Article Professional Blocks panel.

More from this topic
  1. Peroneal Muscular Atrophy of Demyelinating Type

    DefinitionPeroneal muscular atrophy? of demyelinating type is a long-term (chronic?) nerve disease where the protective covering of certain nerves (called myelin) slowly gets damaged. These nerves...

    January 6, 2026 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  2. PMP2-Related Charcot-Marie-Tooth Disease Type 1 ( CMT1 / CMT1G)

    DefinitionPMP2-related Charcot-Marie-Tooth disease type 1 (often called PMP2-related CMT1 or CMT1G) is a very rare inherited nerve disease. It happens when the PMP2 gene, which makes...

    January 5, 2026 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  3. Neuropathy Hereditary Motor and Sensory Type 1C

    DefinitionNeuropathy? hereditary motor and sensory type 1C is usually called Charcot–Marie–Tooth disease type 1C (CMT1C). It is a rare, inherited nerve disease that mainly damages the...

    December 25, 2025 • Rx Neurology (A - Z)
  4. Charcot-Marie-Tooth Neuropathy Type 2N (CMT2N)

    DefinitionCharcot-Marie-Tooth neuropathy? type 2N (CMT2N) is a rare, inherited nerve disease that mainly affects the long nerves in the legs and, later, the arms. It is...

    December 22, 2025 • Rx Neurology (A - Z)
  5. Autosomal Recessive Limb-Girdle Muscular Dystrophy Type 2Z (LGMD2Z; LGMDR21, POGLUT1-related)

    DefinitionAutosomal Recessive Limb-Girdle Muscular Dystrophy Type 2Z (LGMD2Z; LGMDR21, POGLUT1-related) is a rare, inherited muscle disease that mainly weakens the large muscles around the shoulders and...

    October 11, 2025 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  6. Neuronopathy Distal Hereditary Motor Harding Type 6

    DefinitionDistal hereditary motor neuronopathy, Harding type VI (often shortened to dHMN VI or HMN VI), is a rare, inherited nerve disease. It mainly damages the motor...

    October 7, 2025 • Rx Neurology (A - Z)
  7. Autosomal Dominant Intermediate Charcot-Marie-Tooth Disease (CMT-DI)

    DefinitionAutosomal dominant intermediate Charcot-Marie-Tooth disease (CMT-DI) is an inherited nerve disorder that slowly damages the long peripheral nerves supplying the feet, legs, hands, and arms. “Intermediate”...

    October 3, 2025 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  8. Autosomal Dominant Charcot-Marie-Tooth Disease Type 2W (CMT2W)

    DefinitionAutosomal dominant Charcot-Marie-Tooth disease type 2W (CMT2W) is a hereditary nerve disorder that mainly damages the long peripheral nerves that move your feet and hands and...

    October 2, 2025 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  9. Charcot–Marie–Tooth Neuropathy (CMT)

    DefinitionCharcot–Marie–Tooth (CMT) is a group of inherited nerve disorders that slowly damage the long nerves of the arms and legs. These nerves carry signals that let...

    October 2, 2025 • Rx Neurology (A - Z)
  10. Autosomal Dominant Charcot-Marie-Tooth Disease Type 2M (CMT2M)

    DefinitionAutosomal Dominant Charcot-Marie-Tooth Disease Type 2M (CMT2M) is a rare, inherited nerve disease that mainly damages the axon (the long wire) of peripheral nerves. It weakens...

    October 2, 2025 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)