Morphological Variations of Foot Lumbricals and Their Clinical Significance: A Cadaveric Study

The lumbrical muscles of the foot are intrinsic musculature playing a critical role in maintaining toe alignment and facilitating smooth gait mechanics. Despite their importance, morphological variations remain understudied, which can impact clinical diagnostics and surgical outcomes.

This study aims to investigate the morphological variations of the foot lumbricals and their clinical significance using cadaveric dissection.

This study examined 150 lower limbs from 75 formalin-embalmed human cadavers (43 males and 32 females) over the period of 2019-2024. Morphological characteristics of the lumbrical muscles, including origin, insertion, number, and nerve supply, were recorded.

The study revealed a gender variation in the anatomical patterns of the foot lumbricals. In total, 5.33% of cadavers exhibited bilateral unipennate second, third, and fourth lumbricals, with a higher prevalence in females (five cases) compared to males (three cases). Similarly, 8% of cadavers had unilateral unipennate lumbricals, with a dominant occurrence in females (nine cases) versus males (three cases). The absence of the fourth lumbrical was seen in 6% of cadavers, again more frequently in females (six cases) than males (three cases). In addition, accessory lumbricals arising from the flexor hallucis brevis were noted in 2.67% of cadavers, with a higher occurrence in females (three cases) than males (one case). Overall, the findings indicate a gender-based disparity, with females showing a greater frequency of these variations.

Morphological variations in foot lumbricals variations have potential implications in conditions like claw toe deformity and altered gait mechanics and may influence foot biomechanics and surgical outcomes. Recognizing these anomalies is essential for clinicians and surgeons to enhance diagnostic accuracy and optimize therapeutic interventions.