Anatomical and Clinical Insight of Variant Morphologies of Psoas Minor Muscle: a Case Report

Psoas minor is long, slender and functionally weak muscles that assist psoas major in flexing the trunk and spinal column. Psoas minor at its origin lies just in front of the psoas major muscle has small belly and long tendon like plantaris and palmaris longus muscle. Psoas minor receives its nerve supply from the ventral rami of L1 spinal nerves, which after piercing through the psoas major muscle enter into the muscular belly. In the present case, psoas minor muscle was found bilaterally in a 60 years old male formalin fixed cadaver. Bilaterally, the muscle depicted absence of fusion with adjacent psoas major and was found to exist independently. The distal insertion of the muscle was variable when compare to the contralateral peer. Moreover, in contrast to the muscular portion, the tendinous portion was remarkably lengthier. As the muscle is closely related to important neurovascular structures of retroperitoneum, it may compress them during its involvement in psoas minor syndrome and psoas abscess; yielding myriads of clinical signs and symptoms. The incidence and morphometric parameters of this inconsistent muscle are highly variable and had been frequently correlated with ethnic and racial characteristics. The current report reveals a case of bilateral existence of psoas minor and disparity in its morphometric attributes on either side. Against this background, analysis of deviation in structural architecture and its distribution in population has been attempted. To consolidate the scattered pieces of information about variability in different parameters of this muscle and reemphasize its significant role in radiographic and surgical procedures, a review of literature is constructed to appraise the medical persons working in related fields.