The Prevalence of Absence of the Palmaris Longus Muscle among Medical Students in Benghazi, Libya
Keywords:
Palmaris longus, Thompson’s testtAbstract
Palmaris longus muscle (PL) is one of the most superficial flexor muscles of the forearm. It
is slender and fusiform in shape which lies medial to flexor carpi radialis muscle. It exhibits
variability in its prevalence across various ethnicities and geographical areas. Six hundred sixty
medical students (275 males, 385 females) aged between 17 to 25 years were included after their
consent and examined for the prevalence of absence of the PL muscle tendon. Each student was
initially asked to do the Schaeffer‘s test if not visible then simultaneously followed by Thompson‘s
test and Pushpakumar‘s "two-finger sign" for the assessment of the PL tendon. 660 medical students
in Benghazi-Libya. The overall absence of palmaris longus was seen in 163 students (24.7%) 56 of
whom were males (20.4%) and 107 of whom were females (27.8%). Palmaris longus was found absent
unilaterally in 14.85% of the students and bilaterally in 9.85% of the students. In comparison to males
(20.4%), females had a somewhat higher prevalence of Palmaris longus absent (27.8%). Palmaris
longus was absent in 6.52% (43 students) on the right side and in 8.33% (55 students) on the left side.
The left-side agenesis was seen in 34 females (8.8%) and 21 males (7.6%). The right-side agenesis was
seen in 28 females (7.3%) and 15 males (5.5%). Out of 65 (9.8%) bilateral agenesis, 45 (11.7%) were
females and 20 (7.3%) were males. PL muscle is very useful in plastic and orthopedic surgeries.
Overall, the palmaris longus was absent in 24.7% of the entire sample. It is possible to carry out more
research to determine the relationship between the palmaris longus muscle and several factors
including hand dominance, ethnicity, etc.
References
References
Drake, R., A.W. Vogl, and A.W. Mitchell, Gray's anatomy for students E-book. 2009: Elsevier Health Sciences.
Kassim, N.M., et al., The Incidence of Agenesis of Palmaris Longus Muscle Among Multiracial Medical Students of University Malaya, Malaysia. Indian Journal of Surgery, 2020. 82: p. 486-491.
Snell, R.S., Clinical anatomy by regions. 2011: Lippincott Williams & Wilkins.
Soltani, A.M., et al., The variation in the absence of the palmaris longus in a multiethnic population of the United States: an epidemiological study. Plastic Surgery International, 2012. 2012.
Nasiri, E., M. Pourghasem, and H. Moladoust, The prevalence of absence of the palmaris longus muscle tendon in the north of Iran: a comparative study. Iranian Red Crescent Medical Journal, 2016. 18(3).
Alabbad, A., et al., The Frequency of Palmaris Longus Absence among Female Students in King Faisal University in Al-Ahsa, Saudi Arabia. The Egyptian Journal of Hospital Medicine, 2018. 70(11): p. 1959-1962.
Sebastin, S., et al., The prevalence of absence of the palmaris longus–a study in a Chinese population and a review of the literature. Journal of Hand Surgery, 2005. 30(5): p. 525-527.
Javaid, Q., A. Usmani, and A. Surti, Clinical assessment of absence of palmaris longus muscle and its association with ethnicity. JPMA, 2023. 73(1029): p. 1.
Javaid, Q., Prevalence of agenesis of palmaris longus in male and female genders on clinical examination-a review. JPMA. The Journal of the Pakistan Medical Association, 2022. 72(4): p. 733-737.
Georgiev, G.P., Palmaris longus muscle variants: well known, but what’s new. Int J Anat Var, 2019. 12(001).
Kyung, D.-S., et al., Different frequency of the absence of the palmaris longus according to assessment methods in a Korean population. Anatomy & Cell Biology, 2012. 45(1): p. 53-56.
Lahiji, F.A., K. Ashoori, and M. Dahmardehei, Prevalence of palmaris longus agenesis in a hospital in Iran. Archives of Iranian medicine, 2013. 16(3): p. 0-0.
Kigera, J.W. and S. Mukwaya, Frequency of agenesis palmaris longus through clinical examination-an East African study. PloS one, 2011. 6(12): p. e28997.
Ceyhan, O. and A. Mavt, Distribution of agenesis of palmaris longus muscle in 12 to 18 years old age groups. Indian journal of medical sciences, 1997. 51(5): p. 156-160.
Raouf, H.A., et al., Frequency of palmaris longus absence and its association with other anatomical variations in the Egyptian population. Clinical Anatomy, 2013. 26(5): p. 572-577.
Sabouba, M., et al., Prevalence of Absence of the Palmaris Longus Muscle among Medical Students of An-Najah National University: A Cross-Sectional Study from Palestine. Palestinian Medical and Pharmaceutical Journal (Pal. Med. Pharm. J.), 2021. 7(1): p. 77-84.
Sater, M.S., A.S. Dharap, and M.F. Abu‐Hijleh, The prevalence of absence of the palmaris longus muscle in the Bahraini population. Clinical Anatomy, 2010. 23(8): p. 956-961.
Hussain, F.N. and T. Hasan, Prevalence of congenital absence of Palmaris Longus tendon in young Jizani population of Saudi Arabia: A cross sectional study. 2012.
JP, S., On the variations of the palmaris longus muscle. Anat Rec, 1909. 3: p. 275-278.
Thompson, J., J. McBatts, and C.H. Danforth, Hereditary and racial variation in the musculus palmaris longus. American Journal of Physical Anthropology, 1921. 4(2): p. 205-218.
SB, P., The'two-finger'sign: Clinical examination of palmaris longus tendon. Br J Plast Surg, 2004. 57: p. 184.
Tallia, A.F. and D.A. Cardone, Diagnostic and therapeutic injection of the wrist and hand region. American family physician, 2003. 67(4): p. 745-750.
Ravi, N., et al., Palmaris Longus Tendon Absence in Pre-Clinical Medical Students of Universiti Malaysia Sabah. Borneo Journal of Medical Sciences (BJMS), 2020. 14(1).
Venter, G., A.-N. Van Schoor, and M.C. Bosman, Degenerative trends of the palmaris longus muscle in a South African population. Clinical Anatomy, 2014. 27(2): p. 222-226.
Thompson, N., B. Mockford, and G. Cran, Absence of the palmaris longus muscle: a population study. The Ulster medical journal, 2001. 70(1): p. 22.
Kose, O., et al., The prevalence of absence of the palmaris longus: a study in Turkish population. Archives of Orthopaedic and Trauma Surgery, 2009. 129: p. 609-611.
Morais, M., et al., Prevalence of agenesis of the palmaris longus muscle in Brazil and its clinics correlation. Journal of Morphological Sciences, 2017. 29(4): p. 0-0.
Mbaka, G., et al., The incidence of agenesis of Palmaris longus among the yoruba tribe in Nigeria. Nigerian Journal of Medical Rehabilitation, 2008: p. 11-14.
Gangata, H., The clinical surface anatomy anomalies of the palmaris longus muscle in the Black African population of Zimbabwe and a proposed new testing technique. Clinical Anatomy: The Official Journal of the American Association of Clinical Anatomists and the British Association of Clinical Anatomists, 2009. 22(2): p. 230-235.
Abledu, J. and E. Offei, Prevalence of agenesis of palmaris longus and its association with gender, body side, handedness and other anomalies of the forearm in a student population in Ghana. Rawal Medical J, 2014. 39(2): p. 203-207.
Mbaka, G.O. and A.B. Ejiwunmi, Prevalence of palmaris longus absence–a study in the Yoruba population. The Ulster medical journal, 2009. 78(2): p. 90.
Berhe, T. and A. Bekele, Agenesis of palmaris longus muscle among selected Ethiopian students. Anatomy & Physiology: Current Research, 2014. 4(2): p. 1-5.
Kapoor, S.K., et al., Clinical relevance of palmaris longus agenesis: common anatomical aberration. Anatomical science international, 2008. 83: p. 45-48.
Roohi, S., et al., A study on the absence of palmaris longus in a multiracial population. Malaysian Orthopaedic Journal, 2007. 1(1): p. 26-28.
Sebastin, S.J., A.Y. Lim, and H. Wong, Clinical assessment of absence of the palmaris longus and its association with other anatomical anomalies-a Chinese population study. Annals-academy of Medicine Singapore, 2006. 35(4): p. 249.
Agarwal, P., Absence of the palmaris longus tendon in Indian population. Indian journal of orthopaedics, 2010. 44: p. 212-215.
Alves, N., D. Ramírez, and N.F. Deana, Study of frequency of the palmaris longus muscle in Chilean subjects. International Journal of Morphology, 2011. 29(2): p. 485-489.
Erić, M., et al., Prevalence of the palmaris longus through clinical evaluation. Surgical and radiologic anatomy, 2010. 32: p. 357-361.
Sankar, K.D., P.S. Bhanu, and S.P. John, Incidence of agenesis of palmaris longus in the Andhra population of India. Indian Journal of Plastic Surgery, 2011. 44(01): p. 134-138.
