The palmaris longus muscle (PLM) occurs in various forms in the human body, with its complete absence being the most common variation. Although the PLM is frequently used in reconstructive surgeries, its functional impact, especially on fine motor skills, remains unclear and has not been directly studied.
Objective
This study aimed to investigate whether the presence or absence of the PLM affects gross grip strength, pinch grip strength, wrist joint proprioception, and fine motor skills, thereby determining if the PLM has a functional role in hand performance.
Methods
A total of 497 individuals were assessed for the presence of the PLM. Of these, 36 individuals were found to lack the PLM unilaterally or bilaterally. For comparability, 35 individuals with the PLM were included in the analysis. Gross grip strength and pinch grip strength were measured using a hand dynamometer, wrist joint proprioception was assessed with a digital inclinometer, and fine motor skills were evaluated with the Purdue Pegboard Test.
Results
No significant differences were found between individuals with the PLM and individuals without the PLM in terms of gross grip strength, pinch grip strength, wrist joint proprioception, or fine motor skills in either the dominant or nondominant hand (p > 0.05).
Conclusions
The presence or absence of the PLM does not affect fine motor skills, grip strength, or wrist proprioception, suggesting it can be safely used for surgical grafting without functional loss in the hand.
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