Abstract

Introduction: The psoas muscle group, including the major and minor muscles, shows variability among individuals. The psoas major is consistently present, while the psoas minor has a higher absence rate (40-60%). Evolution has influenced its absence in humans due to upright posture and bipedal gait. Objectives: This study aims to provide insights into the incidence and morphology of the psoas minor in the South Indian population, addressing literature gaps and discussing its clinical significance. Methods: Conducted at the Department of Anatomy, Adichunchanagiri Institute of Medical Sciences, B.G. Nagara, Karnataka, the study analyzed 16 cadavers. Measurements included muscle and tendon length, muscle width, origin, and insertion points. Results: The psoas minor was found in 5 of the 16 cadavers, with unilateral and bilateral occurrences in 2 and 3 cadavers, respectively. The mean lengths of the muscle and tendon were 8.5 cm and 8.8 cm, respectively. The origin was from the body of T12 and L1 vertebrae, including adjoining vertebral discs, with variable insertion points. The mean muscle width was 1.70 cm.  Conclusion: Despite its vestigial and variable nature, the psoas minor was observed in 31.25% of the population studied. Its presence, though infrequent, may play a role in conditions like psoas minor syndrome, where muscle stiffness can occur. Detailed knowledge of the psoas minor is crucial for proper diagnosis and treatment.

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