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    Related Topics

    From Musculoskeletal System

    Metatarsals (5 bones)
    5 bones forming the mid-foot.
    Rectus Abdominis
    Abs muscle that flexes the trunk.
    Sternum
    Breastbone located in the center of the chest.
    Zygomatic Bones
    Cheekbones that form part of the orbit.
    Deltoid
    Shoulder muscle responsible for arm abduction.
    Ethmoid Bone
    Bone forming part of the nasal cavity and the orbit.
    Gomphoses
    Fibrous joints where a peg fits into a socket (e.g., teeth in jaw).
    Palatine Bones
    Bones forming part of the hard palate and nasal cavity.
    Obliques (External and Internal)
    Muscles responsible for torso rotation.
    Buccinator
    Muscle that helps with chewing and blowing air out.
    Mandible
    Lower jawbone that houses the teeth.
    Rotator Cuff Muscles
    Supraspinatus, Infraspinatus, Teres Minor, Subscapularis.
    Ulna
    Forearm bone on the pinky side.
    Latissimus Dorsi
    Back muscle responsible for arm adduction and extension.
    Pivot Joints
    e.g., atlanto-axial joint
    Biceps Brachii
    Muscle responsible for elbow flexion.
    Triceps Brachii
    Muscle responsible for elbow extension.
    Gliding (Plane) Joints
    e.g., between carpals
    Lumbar Vertebrae (L1 - L5)
    Vertebrae in the lower back (L1-L5).
    Pectoralis Major
    Chest muscle responsible for shoulder movement.
    Ellipsoidal (Condyloid) Joints
    e.g., wrist
    Iliolumbar Ligament
    Ligament connecting the ilium and lumbar vertebrae.
    Sartorius
    Longest muscle in the body responsible for hip flexion.
    Sphenoid Bone
    Bone forming part of the base of the skull and sides of the orbits.
    Frontal Bone
    Bone forming the forehead and upper part of the orbits.

    Fibula

    Reviewed by our medical team

    Smaller bone in the lower leg, located alongside the tibia.

    1. Overview

    The fibula is the slender, lateral bone of the lower leg that runs parallel to the tibia. Although it does not significantly contribute to weight-bearing, it plays a critical role in stabilizing the ankle, supporting muscle attachments, and forming part of the lateral aspect of the leg. It is one of the two bones of the leg (along with the tibia) and extends from the knee to the ankle joint.

    2. Location

    The fibula is located in the lateral compartment of the lower limb:

    • Proximally: Articulates with the lateral aspect of the tibia at the superior tibiofibular joint (below the knee joint).

    • Distally: Forms the lateral malleolus, which contributes to the ankle joint and articulates with the talus bone of the foot.

    • Medially: Lies adjacent and parallel to the tibia, connected by the interosseous membrane.

    3. Structure

    The fibula is a long, thin bone consisting of three main parts:

    • Head: Proximal end that articulates with the lateral condyle of the tibia; contains the apex and a facet for articulation.

    • Neck: Narrow region just below the head, where the common fibular nerve courses closely, making it vulnerable to injury.

    • Shaft (body): Long, slightly twisted body with surfaces for muscle attachments.

    • Lateral malleolus: Distal end of the fibula that forms the outer part of the ankle joint; contributes to ankle stability.

    • Joints:

      • Proximal tibiofibular joint: Synovial joint with limited mobility.

      • Distal tibiofibular joint: Fibrous syndesmosis, essential for ankle integrity.

    • Blood supply: Mainly from the fibular (peroneal) artery, a branch of the posterior tibial artery.

    4. Function

    While the fibula does not bear substantial weight, it has several key biomechanical functions:

    • Stabilizes the ankle: The lateral malleolus provides structural support to the ankle joint, preventing excessive eversion.

    • Supports muscle attachment: Serves as a site for origin and insertion of muscles in the lateral and posterior leg compartments (e.g., peroneus longus and brevis, soleus).

    • Transmits minimal load: Carries about 10% of the body’s weight, compared to 90% carried by the tibia.

    5. Physiological role(s)

    The fibula contributes to several important physiological and functional processes:

    • Balance and locomotion: Aids in stabilizing the lower leg and foot during gait, running, and balance activities.

    • Force dispersion: Although limited in load-bearing, it assists in distributing forces during lateral leg motion and rotation.

    • Bone grafting source: The fibula is commonly used in reconstructive bone graft surgeries due to its expendable nature and strong cortical structure.

    • Nerve protection: Provides a path for the common fibular nerve, though its superficial course makes it prone to injury.

    6. Clinical Significance

    The fibula is involved in various orthopedic and neurological conditions:

    • Fibular fractures:

      • Common with ankle injuries or direct trauma; may occur alone or with tibial fractures.

      • Lateral malleolus fractures can compromise ankle stability and require surgical fixation.

    • Common fibular nerve injury:

      • May occur with fibular neck fractures or compression; leads to foot drop and sensory loss on the dorsum of the foot.

    • Chronic ankle instability:

      • Involves weakening of the lateral ligament complex and malleolar support, often requiring physical therapy or surgical repair.

    • Osteomyelitis or tumors:

      • Though rare, fibular involvement in infections or neoplasms may necessitate partial or complete resection.

    • Graft donor site:

      • Fibular segments are often harvested for reconstructive surgeries in the mandible, spine, or long bone defects.

    Did you know? Your bones are constantly adapting to the mechanical forces placed on them.