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    Ischium
    Part of the pelvis that supports weight while sitting.
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    e.g., between carpals
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    Knee ligament that stabilizes the joint.
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    Tendons that help extend the fingers and toes.
    Pubis
    Part of the pelvis that joins with the opposite side to form the pubic symphysis.
    Abductor Digiti Minimi Muscle
    The abductor digiti minimi muscle is a hypothenar muscle that abducts and flexes the little finger, aiding grip and precision in hand movements.
    Maxillae
    Upper jaw bones that house the teeth and form part of the orbit.
    Lacrimal Bones
    Bones forming part of the eye socket and housing the tear ducts.
    Sartorius
    Longest muscle in the body responsible for hip flexion.
    Coccygeus
    Pelvic floor muscle supporting the coccyx.
    Biceps Tendon
    Tendon that attaches the biceps muscle to the bone.
    Soleus
    Calf muscle responsible for plantarflexion of the foot.
    Thoracic Cage
    Ribs and sternum forming the protective cage for the heart and lungs.
    Sternocleidomastoid
    Muscle that rotates and flexes the neck.
    Obliques (External and Internal)
    Muscles responsible for torso rotation.
    Pelvic Floor Muscles
    Muscles that support pelvic organs.
    Temporal Bones
    Bones forming the lower sides of the skull and housing the ears.
    Mandible
    Lower jawbone that houses the teeth.
    Metatarsals (5 bones)
    5 bones forming the mid-foot.
    Facial Bones
    Bones forming the structure of the face.

    Brachioradialis

    Reviewed by our medical team

    Muscle responsible for forearm flexion.

    1. Overview

    The brachioradialis is a superficial muscle of the lateral forearm that plays a key role in elbow flexion. Although it anatomically belongs to the posterior (extensor) compartment of the forearm, it acts functionally as a flexor. It is most active when the forearm is in a mid-pronated (neutral) position, such as during a handshake or when lifting with a hammer grip. The brachioradialis is also useful in clinical assessments of the radial nerve through the brachioradialis reflex.

    2. Location

    The brachioradialis is located in the lateral aspect of the forearm, stretching from the arm to the distal forearm:

    • Origin: Lateral supracondylar ridge of the humerus, just above the lateral epicondyle.

    • Insertion: Lateral surface of the distal radius, near the styloid process.

    It lies superficially and forms the lateral border of the cubital fossa, visible and palpable when the elbow is flexed against resistance.

    3. Structure

    The brachioradialis has the following structural features:

    • Muscle type: Fusiform (spindle-shaped), with a long belly and narrow distal tendon.

    • Innervation: Radial nerve (C5–C6), despite its role as a flexor (most flexors are innervated by the musculocutaneous nerve).

    • Vascular supply: Receives blood from the radial recurrent artery.

    It does not cross the wrist joint and thus does not contribute to wrist movement.

    4. Function

    The brachioradialis performs the following functions:

    • Primary action: Flexes the elbow, especially when the forearm is in a neutral (midway between pronation and supination) position.

    • Secondary role: Assists in stabilizing the elbow during rapid or forceful flexion.

    • Minimal contribution: Weakly aids in pronation or supination to bring the forearm to the neutral position.

    5. Physiological role(s)

    The brachioradialis is involved in several physiological and functional activities:

    • Functional movements: Important in lifting objects, turning doorknobs, or using tools in a neutral grip.

    • Reflex testing: The brachioradialis reflex (C6) is used in neurological exams to test the integrity of the radial nerve and spinal cord segments.

    • Dynamic stability: Assists with elbow joint stability during fast upper limb motions.

    6. Clinical Significance

    The brachioradialis is involved in a number of clinical conditions and is important in diagnostics:

    • Brachioradialis reflex: A diminished or absent reflex may indicate radial nerve injury or C6 spinal nerve involvement.

    • Overuse injuries: May be strained in individuals who perform repetitive elbow flexion with a neutral grip, such as construction workers or athletes.

    • Radial tunnel syndrome: Compression of the radial nerve near the elbow may affect brachioradialis function, causing pain or weakness.

    • Differential diagnosis: Pain over the lateral forearm may mimic lateral epicondylitis (tennis elbow), but brachioradialis tenderness is more distal.

    Did you know? The wrist has 8 bones, while the ankle has 7.