Clinical assessment of agenesis of palmaris longus muscle and its association with gender, body sides in western Indian population

Abstract

Background: Palmaris longus muscle is a degenerating superficial flexor muscle of forearm. Absence of palmaris longus in different ethnic groups has been frequently encountered in clinical practice. Aim & Objectives: Present study was done to determine the incidence of unilateral and bilateral absence of palmaris longus and its association with gender and sides of the upper limb in western Indian population. Methods & Material: The sample constituted 500 healthy subjects (250 males and 250 females) which were examined clinically by standard technique. In subjects with an absence of palmaris longus tendon, three other clinical tests were performed to confirm its absence. Results: Overall absence of palmaris longus was observed in 91 subjects (18.2%) out of which 48 (9.6%) had unilateral absence and 36 (7.2%) had bilateral absence. Frequency of unilateral (Males: 8.4%, Females: 10.8%) and bilateral (Males: 5.2%, Females: 9.2%) agenesis was higher in females. In males, unilateral (8.4%) agenesis was more common than bilateral (5.2%). In subjects with unilateral agenesis right side (5.2%) was more commonly involved than left side (3.2%) in males whereas in females left side (7.2%) was more commonly involved than right (3.6%). However in present study there was no statistical association observed between absence of palmaris longus and gender or body sides in western Indian population. Conclusion: Agenesis of palmaris longus, both forms unilateral and bilateral was fairly common in western Indian population in both gender. Females had higher incidence of agenesis than males with unilateral agenesis more common than bilateral.