Anatomical Relations
The flexor retinaculum is continuous with the palmar carpal ligament. The ulnar artery and nerve and cutaneous branches of the median and ulnar nerves pass superficial to the flexor retinaculum. It forms the roof of the carpal tunnel through which the tendons of flexor digitorum profundus, flexor digitorum superficialis, flexor pollicis longus, and the median nerve pass through to enter the hand. The tendon of flexor carpi radialis travels through its own canal within the retinaculum. The floor of the carpal tunnel is formed by the carpal bones.
Related parts of the anatomy
Structure
The flexor retinaculum is a strong fibrous band that covers the carpal bones of the palmar side of the hand. The distal border of the flexor retinaculum is concave inferiorly and is attached to the tubercle of the trapezium and to the hook of the hamate. Its proximal border is concave superiorly and is attached to the tubercle of the scaphoid and pisiform bone. When the wrist is flexed three creases in the skin of the wrist are usually present. The most distal and dominant is the proximal edge of the flexor retinaculum.
Function
The function of the flexor retinaculum of the wrist is to protect the structures that transverse the carpal tunnel.
List of Clinical Correlates
—Carpal tunnel syndrome
