A Medial View of the Flexor Retinaculum of the Male

Description

Seen from the medial aspect of the male wrist, the flexor retinaculum (transverse carpal ligament) spans from the pisiform and hook of hamate ulnarly to the scaphoid tubercle and trapezium radially, forming a tough fibrous roof over the volar carpal arch. Deep to it lies the carpal tunnel, with the median nerve positioned superficial to the flexor tendons as they course distally into the palm. Ulnar and slightly superficial to the retinaculum, the ulnar nerve and ulnar artery pass through Guyon’s canal between the pisiform and hamate. Thick fascia. Clear boundaries. A medial view matters because the ulnar attachments and the relationship to Guyon’s canal are easy to teach and easy to misunderstand when you only work from palmar schematic diagrams. This angle supports clinical correlation with ulnar neuropathy at the wrist (handlebar palsy) and distinguishes it from carpal tunnel syndrome, where median nerve compression occurs deep to the retinaculum and is often provoked by tenosynovitis of flexor digitorum superficialis and profundus. Surgeons also reference these landmarks during open or endoscopic carpal tunnel release to divide the retinaculum while avoiding injury to the palmar cutaneous branch of the median nerve and the ulnar neurovascular bundle. Use this illustration in gross anatomy lab manuals, hand and upper-limb lecture slides, and operative anatomy figures discussing carpal tunnel release, Guyon’s canal decompression, and tendon sheath pathology in the distal forearm and palm. It also fits patient-facing education when you need a clean explanation of why symptoms in the ring and little fingers point away from the median nerve. Anatomical accuracy verified by SciePro's Medical Advisory Board.