Martin-Gruber anastomosis revisited

Area of Science:

• Anatomy
• Neuroscience
• Human cadaver studies

Background:

• The Martin-Gruber anastomosis is a neural connection between the median and ulnar nerves in the forearm.
• Existing classifications may not fully capture the variations of this anatomical structure.
• Understanding these variations is crucial for surgical procedures and neurological assessments.

Purpose of the Study:

• To propose a novel classification system for the Martin-Gruber anastomosis.
• To determine the prevalence and anatomical characteristics of the Martin-Gruber anastomosis in a human cadaver population.
• To analyze the branching patterns and course of the anastomotic connections.

Main Methods:

• Examination of 70 human cadavers (31 male, 39 female).
• Analysis of previously reported cases to supplement cadaveric findings.
• Classification of the anastomosis based on the number of branches, origin from the median nerve (Types a, b, c), and course relative to the ulnar nerve and artery.

Main Results:

• The Martin-Gruber anastomosis was identified in 16 (22.9%) of 70 cadavers, occurring in 19 (13.6%) of 140 forearms.
• Pattern I (single branch) occurred in 89.5% of cases, while Pattern II (two branches) occurred in 10.5%.
• Branch origins were classified as Type a (47.3%), Type b (10.6%), and Type c (31.6%), with Pattern II being a duplication of Type c.

Conclusions:

• A new classification system for the Martin-Gruber anastomosis has been established, categorizing it into Patterns I and II with specific branch Types (a, b, c).
• The study provides detailed prevalence data and describes the anatomical course and variations of this anastomosis.
• This refined classification enhances the understanding of forearm nerve anatomy and aids in clinical applications.