The extensor retinaculum of the wrist

Area of Science:

• Anatomy
• Orthopedics
• Biomechanics

Background:

• The dorsal retinaculum stabilizes wrist extensor tendons.
• Understanding its structure is crucial for wrist function and injury assessment.

Purpose of the Study:

• To detail the anatomical structure of the dorsal retinaculum.
• To clarify the complex anatomy of the sixth extensor compartment.
• To evaluate the retinaculum's role in wrist stability.

Main Methods:

• Detailed anatomical dissection of the dorsal wrist retinaculum.
• Histological examination of retinacular layers and septa.
• Analysis of the extensor carpi ulnaris tendon sheath.

Main Results:

• The dorsal retinaculum comprises supratendinous and infratendinous layers.
• Six distinct compartments house dorsal wrist tendons, separated by septa originating from the supratendinous layer.
• The sixth compartment (extensor carpi ulnaris) is a complex fibrous tunnel with unique medial reinforcement (linea jugata).

Conclusions:

• The dorsal retinaculum's intricate structure, particularly the sixth compartment, highlights its role in dynamic wrist stabilization.
• Findings suggest the retinaculum functions as an adaptable collateral ligament system, challenging traditional biomechanical models.