The anatomy and function of Cleland's ligaments

Area of Science:

• Anatomy
• Biomechanics
• Dermatology

Background:

• The morphology of digital cutaneous ligaments, particularly Cleland's ligaments, has been inconsistently described, leading to surgical uncertainty.
• Previous descriptions lacked precision regarding the structure and dynamic function of these ligaments in the digits.

Discussion:

• Micro-dissection of 24 fresh frozen fingers revealed distinct proximal interphalangeal (PIP) and distal interphalangeal (DIP) ligament systems.
• PIP ligaments originate from the PIP joint and proximal/middle phalanx, with proximal (PIP-P) and distal (PIP-D) components inserting into the skin.
• DIP ligaments mirror this arrangement, originating from the DIP joint and middle phalanx, with proximal (DIP-P) and distal (DIP-D) fibers.

Key Insights:

• PIP ligaments exhibit three distinct layers originating from the flexor tendon sheath, periosteum/joint capsule, and extensor expansion.
• DIP ligaments possess two layers, corresponding to the anterior two layers of the PIP ligaments.
• These ligaments function as crucial skin anchors, stabilizing skin relative to the skeleton during motion.

Outlook:

• Understanding these ligamentous structures is vital for accurate surgical interventions involving the digits.
• Further research could explore the biomechanical implications of these ligaments in various hand and finger pathologies.
• Investigating the precise role of each ligament layer may reveal new therapeutic targets.