Prolotherapy: Targets Carpal and Palmar ligaments

By Jon Trister MD

Prolotherapy is an effective treatment for various wrist and hand issues associated with laxity, instability, and altered function in these areas. The following structures are commonly targeted for Prolotherapy injections:

Carpal Ligaments  

The carpal ligaments comprise both intrinsic (connecting carpal bones) and extrinsic (connecting forearm bones to carpal bones) structures.

Transverse Carpal Ligament (TCL)  

The TCL is a thick fibrous band that spans the volar aspect of the wrist, forming the roof of the carpal tunnel. It attaches medially to the pisiform and hook of the hamate, and laterally to the scaphoid tuberosity and trapezium. Its key functions include:

– Formation of the Carpal Tunnel: The TCL creates a fibro-osseous tunnel that houses the median nerve and flexor tendons, protecting these components from external forces while allowing for smooth tendon gliding during wrist and finger movements.

– Biomechanical Stability: The TCL stabilizes the carpal bones by maintaining their arch-like configuration, which helps distribute axial loads across the wrist during weight-bearing activities.

– Pulley Function: Acting as a pulley system for flexor tendons, it ensures efficient force transfer from forearm muscles to the fingers.

• Muscle Attachment Site: Portions of the thenar (e.g., abductor pollicis brevis) and hypothenar (e.g., flexor digiti minimi brevis) muscles originate from the TCL, contributing to movements of the thumb and little finger.

The transverse palmar ligament (also known as the deep transverse metacarpal ligament) and the carpal ligaments, including the transverse carpal ligament (TCL) and the palmar carpal ligament, play vital roles in maintaining the form and function of the wrist and hand. These ligaments provide stability, facilitate movement, and protect essential anatomical components such as nerves, tendons, and blood vessels.

Transverse Palmar Ligament  

The transverse palmar ligament (also known as the deep transverse metacarpal ligament)

The transverse palmar ligament connects the heads of the metacarpal bones of the second to fifth fingers on their palmar surfaces. It serves several important purposes:

– Stability of Metacarpophalangeal (MCP) Joints: It prevents excessive separation of the metacarpal heads during finger movements, ensuring proper alignment and stability of the MCP joints.

– Facilitation of Grip: By stabilizing the MCP joints, this ligament contributes to grip strength and precision during hand functions such as grasping or pinching.

– Protection of Soft Tissues: The ligament creates functional spaces that house blood vessels, nerves, and intrinsic hand muscles, shielding these structures during hand movements.

Functional Importance 

Together, these ligaments ensure:

1. Structural Integrity: They stabilize both the proximal (carpal) and distal (metacarpal) components of the wrist-hand complex.

2. Facilitation of Movement: They allow a wide range of wrist motions—flexion, extension, adduction, and abduction—while maintaining alignment.

3. Protection of Neurovascular Structures: By forming tunnels or compartments (such as the carpal tunnel), these ligaments shield critical nerves like the median nerve from compression or injury.

4. Force Transmission: They enable the efficient transfer of forces from forearm muscles to the fingers during activities that require strength or precision.

Damage or dysfunction in these ligaments can lead to conditions such as carpal tunnel syndrome (caused by compression of the median nerve due to TCL thickening) or instability in the MCP joints. Understanding the anatomy and biomechanics of these structures is crucial for accurately diagnosing and effectively treating wrist-related injuries.