The prevalence of absence of the palmaris longus: a study in Turkish population

It is well known that there is a wide variation in the reported prevalence of the palmaris longus (PL) absence in different ethnic groups. This prospective study was conducted to determine the prevalence of absence of PL and correlate it with gender and body side in Turkish population. In total, 1,350 randomly selected adult patients (675 men and 675 women) who admitted to our outpatient clinic were examined for the absence of PL using Schaeffer's test and Mishra's second test. The absence of PL on both sides, results of the first and second examination tests, age, gender and dexterity were recorded and analyzed statistically. The overall prevalence of absence of PL (unilateral or bilateral) was 26.6% in Turkish population. The absence of PL in women was statistically more common than men. Bilateral absence of PL was statistically frequent than unilateral absence. The prevalence of absence of PL was statistically similar between the body sides. Mishra's second test which involves resisted abduction of the thumb, may be better in demonstration of the PL where the muscle was feebly developed, particularly in women.