Frequency of the Agenesis of Palmaris Longus and Flexor Digitorum Superficialis Tendons Among Individuals

Abstract

Objective: To find out the frequency of hereditary absence of palmaris longus and flexor digitorum superficialis tendons among individuals visiting physiotherapy clinics of 2 hospitals in Pakistan. Methods: This cross-sectional study was conducted in Government hospitals in twin cities (Islamabad and Rawalpindi), Pakistan from September 2018 to March 2019. For examination, a standardized clinical Schaeffer's test and three additional tests were used for the assessment of palmaris longus (PL), and a standardized simple, and the modified test was used for flexor digitorum superficialis (FDS). Data were analyzed by using SPSS 23. Results: Out of 619 individuals, 51.7% were men and 48.3% women were examined. The mean age of males was 33.4 years ± 14.5 and of females 35.9 years ± 13.4. Palmaris longus muscle was absent in 49.3% of participants with bilateral absence being more common. Unilateral absence of the PL muscle was found to be more in the left hand. Its absence in the left hand was found more common in females than in males (11.7% females, 9.1% males). This research showed agenesis of PL is gender dependent. (p< 0.05), and no association was found among the standard FDS and PL tendon test, that is r (617) =0.046, p= 0.249. Conclusion(s): The absence of palmaris longus muscle is more frequently found in women and in the left hand. Agenesis of FDS is rare in individuals and has no association with agenesis of palmaris longus. Keywords: Association, agenesis, humans, muscle, population.