Flexor muscles

Flexor Muscles

Flexor muscles are a group of muscles that serve to decrease the angle between bones on two sides of a joint, such as bending the elbow or knee. These muscles are essential for various movements and functions in the human body, particularly in the limbs.

Anatomy and Function

Flexor muscles are primarily located in the anterior compartments of the limbs. They are responsible for flexion, which is the action of bending a joint. The major flexor muscles in the human body include:

Upper Limb Flexors

• Biceps Brachii: This muscle is located in the upper arm and is responsible for flexing the elbow and supinating the forearm.
• Brachialis: Situated beneath the biceps, it is a strong flexor of the elbow.
• Flexor Carpi Radialis: This muscle flexes and abducts the wrist.
• Flexor Carpi Ulnaris: It flexes and adducts the wrist.
• Flexor Digitorum Superficialis: This muscle flexes the fingers at the proximal interphalangeal joints.
• Flexor Digitorum Profundus: It flexes the fingers at the distal interphalangeal joints.
• Flexor Pollicis Longus: This muscle flexes the thumb.

Lower Limb Flexors

• Iliopsoas: A major flexor of the hip joint.
• Sartorius: The longest muscle in the human body, it flexes, abducts, and laterally rotates the hip, and also flexes the knee.
• Rectus Femoris: Part of the quadriceps, it flexes the hip and extends the knee.
• Hamstrings: A group of muscles including the biceps femoris, semitendinosus, and semimembranosus, which flex the knee and extend the hip.

Physiology

Flexor muscles work by contracting, which pulls on tendons that are attached to bones, causing movement at the joint. The contraction of flexor muscles is often opposed by extensor muscles, which serve to increase the angle between components of a limb.

Clinical Significance

Flexor muscles can be involved in various medical conditions, such as:

• Tendinitis: Inflammation of the tendons, often due to overuse.
• Carpal Tunnel Syndrome: Compression of the median nerve in the wrist, affecting the flexor tendons of the hand.
• Muscle Strain: Overstretching or tearing of muscle fibers.

Rehabilitation and Strengthening

Strengthening flexor muscles is important for maintaining joint stability and function. Exercises such as bicep curls, wrist curls, and leg raises can help in strengthening these muscles. Rehabilitation often involves physical therapy to restore function and reduce pain.

See Also

• Extensor muscles
• Muscle contraction
• Skeletal muscle

References

• Gray, Henry. Gray's Anatomy: The Anatomical Basis of Clinical Practice. 41st Edition.
• Moore, Keith L., and Arthur F. Dalley. Clinically Oriented Anatomy. 7th Edition.