Topographic Anatomy of the Median Nerve and the Pronator Teres and the Flexor Digitorum Superficialis Muscles / 대한해부학회지

ABSTRACT

The pronator teres syndrome can occur when the median nerve is compressed by the adjacent structures in the proximal forearm. The pronator teres and the flexor digitorum superficialis muscles have been suggested to contribute to this syndrome. This study was performed to clarify the topographical relationship among the median nerve, the pronator teres muscle and the flexor digitorum superficialis muscle in 55 Korean adult cadavers (100 sides of arms). The two heads of the pronator teres muscle met at the point of 61.3 mm distal to the biepicondylar line and inserted to the radius at the point of 141.5 mm distal to the line. The ulnar side of its ulnar head was muscular in 8%, tendinous in 70%, and mixed in 20%. The radial side of its humeral head was muscular in 53%, tendinous in 14%, and mixed in 33%. The median nerve was completely covered by the pronator muscle within 26.5 mm from the biepicondylar line and entered between the two heads of the pronator muscle at 54.2 mm from the line and exited it after running 25.5 mm. The most distal part of the musculotendinous arch of the flexor digitorum superficialis muscle was located at the average 80.9 mm from the biepicondylar line. The distalmost radial head of the flexor digitorum superficialis muscle originated from the distal point of the pronator teres insertion in 28.6%, distal to that point in 54.3%, and proximal to that point in 14.3%.