Targeted Muscle Reinnervation in the Hand: A Technical Roadmap

Area of Science:

• Anatomy
• Surgical Innovation
• Neuroscience

Background:

• Targeted muscle reinnervation (TMR) is a surgical technique to reduce neuroma pain and improve prosthetic control.
• Anatomical knowledge is crucial for successful TMR procedures, particularly in the hand.

Purpose of the Study:

• To identify and measure motor entry points (MEPs) of the hand interossei muscles.
• To provide anatomical roadmaps for TMR in digital nerve neuroma management.

Main Methods:

• Dissection of ten fresh-frozen cadaveric hands.
• Identification and measurement of MEPs for dorsal interossei (DIs) and palmar interossei (PIs) muscles.
• Nerve diameter and proximal nerve length measurements were recorded.

Main Results:

• MEPs for DIs and PIs are located in the central third of the metacarpal.
• Nerve length proximal to MEPs is limited, especially for DIs.
• Motor nerve diameters averaged 0.85-0.97 mm.

Conclusions:

• The second and third palmar interossei motor branches are most accessible for TMR via a volar approach.
• Limited proximal nerve length necessitates using the digital nerve for neurorrhaphy.
• TMR in the hand is technically feasible for digital nerve neuroma management.