Variable Patterns and Size of the Palmaris Longus Muscles in Thais

A study on size and variation of the palmaris longus muscle was performed upon 56 Thai cadavers, 37 males and 19 females. Size of this muscle, both fleshy and tendinous portions, was measured in the length, the with and thickness. No significant difference was found in all parameters between the male and the female. There was also no significant difference between the right and left sides in the male and the female as well. The absence of the palmaris longus was observed in only one case, on the eight side. Exclusive of agenesis, other types of variation were found also. They were duplication of the muscle, absence of the fleshy portion, presence of accessory slips and the digastric type.