Functional anatomy of the wrist

Area of Science:

• Orthopedics
• Anatomy
• Biomechanics

Background:

• Detailed examination of wrist morphology is essential for understanding carpal mechanism.
• The concept of interdependent carpal articulation chains provides a framework for analyzing wrist function.

Purpose of the Study:

• To analyze wrist morphology and its role in the interdependent carpal articulation chains.
• To elucidate the functional mechanics of the radiocarpal and midcarpal joints based on carpal morphology.

Main Methods:

• Morphological analysis of the wrist.
• Conceptualization of 3 parallel longitudinal carpal articulation chains.
• Electromyographic observations to confirm muscle stabilization roles.

Main Results:

• The wrist functions via 3 parallel longitudinal chains, with proximal carpals acting as intercalated bones.
• Simultaneous movement in radiocarpal and midcarpal joints is facilitated by the shape of intercalated bones.
• Intercarpal stability is achieved through the linkage of these chains, with key roles for carpal contacts and the scapholunate interosseous ligament.
• The ulnar articular chain utilizes an articular disk for support, with extensions interfacing with all bones in the chain.
• Electromyography confirmed the stabilizing function of certain muscles based on tendon positioning.

Conclusions:

• Wrist morphology defines interdependent carpal articulation chains crucial for coordinated joint function.
• Intercarpal stability relies on the interconnectedness of these chains and specific ligamentous structures.
• Muscle function, particularly stabilization, is integral to overall wrist biomechanics.