Insidence of Martin-Gruber Anastomosis in Turkey: A Cross-Sectional Study

Martin-Gruber anastomosis (MGA) is a well described anostomosis between the median and ulnar nerves in various levels. MGA involves axons leaving either the main trunk of median nerve or the anterior interosseous nerve, crossing through the forearm to join the ulnar nerve and it’s insidence was reported as %10-40. The incidence of this anastomosis is important so that it can cause confusion in the assesment of nerve injuries, compressive neuropathies and it can show different persentages between different population groups. Our objective is to find out an idea about the incidence of MGA in Turkish population. 100 healthy volunteers were inclueded to our study between an age of 17–73 years. Compound muscle action potentials (CMAPs) and motor conduction velocities of median and ulnar nerves were recorded. MGA was made by following criteria: amplitude of CMAP increased after median nerve stimulation at ante-cubital fossa as compared to stimulation at wrist. The corresponding decrease in CMAP amplitude was found after below elbow stimulation as compared with the wrist stimulation in ulnar nerve conduction studies. Martin-Gruber anastomosis was encountered in 29(6 male, 23 female) patients with a persentage of 29% in our present study. The insidence of MGA in Turkish population is high. Understanding the existence of this anatomic variation, its location and its possible presentation is important for the patient’s quality of life. More studies with increased study groups are needed to make us better understand this condition and its insidence in our population.