Prevalence of Missing Palmaris Longus Muscle in the Arm of Secondary School Children in Ibadan, Nigeria

Abstract

Palmaris longus muscle (PLM) is one of the most inconsistent muscles in the human body whose morphology, nerve supply and functions have been comprehensively discussed. This study examined the prevalence of the agenesis of PLM in relation to sex and handedness in 209 individuals. The subjects were screened for PLM tendon using four different tests; Thompson’s test, Mishra’s test I, Schaeffer’s test and Pushpakumar’s “two-finger sign” method. The data obtained were analyzed statistically by Chi square tests using SPSS software. Total agenesis of PLM was 73 (34.9%); Unilateral: 22 (30.1%) and bilateral: 51 (69.9%). Prevalence was significantly higher in females 51 (49%) than in males 22 (21.4%) (p<0.05) while female individuals have higher agenesis in the right hand. The prevalence of absence of PLM to handedness was higher among right handed individuals compared to the left handed individuals. The prevalence of PLM absence in right handed subjects was more on the left than the right hand (5.4% vs 4.3%) while in the left handed it was more on the right hand (15% vs 0%).