Background and purpose: This study was designed to find a possible correlation between the presence of the palmaris longus (PL) tendon and function of the fifth flexor digitorum superficialis (FDS) and carpal tunnel syndrome (CTS).
Methods: The CTS and normal groups consisted of 60 and 180 hands, respectively. The diagnosis of CTS was confirmed by detailed history taking, physical examination and electrodiagnostic testing. The presence of the PL tendon and function of the fifth FDS were determined by physical examination.
Results: In the CTS group, 16/60 hands (26.7%) did not have a PL tendon and 18/60 hands (30%) were lacking fifth FDS function. In the normal group, 27/180 hands (15%) lacked the PL and 25/180 (13.9%) lacked a functional fifth FDS (P = 0.041 and 0.005 for PL and FDS, respectively). Pain distribution and severity of the disease were not related to absence of either of these tendons (P > 0.05).
Conclusion: Our findings showed that the absence of the PL tendon and fifth FDS function, independently and in combination, is more frequent in patients with CTS. Also we found that the severity of CTS or pain distribution in these patients was not related to the presence or absence of these tendons.