An anatomic study on the Martin-Gruber anastomosis.

The incidence of Martin-Gruber anastomosis was studied. Anatomical dissection of 108 cadaveric arms was performed. The Martin-Gruber anastomosis was found in 23 arms. This anastomosis was classified into four types: Type Ia: Communication between the anterior interosseous and the ulnar nn. (n = 13), Type Ib: Communication between the median and ulnar nn. (n = 1), Type II: Communication between muscular branches of the flexor digitorum profundus m. (n = 8), Type III: Combination of Type Ia or Ib and Type II (n = 1). The incidence of Martin-Gruber anastomosis was found to be significantly higher in the present study than in previous studies.