Investigation of the Morphology of Psoas Major and Quadratus Lumborum Muscles in Sacralized Individuals

Year 2025, Volume: 8 Issue: 4, 145 - 149, 15.07.2025

Gamze Nur Koçer Kahrıman , Fatih Çankal , İlyas Uçar

https://doi.org/10.19127/bshealthscience.1662037

Abstract

This study aimed to evaluate the morphological characteristics of the Psoas Major (PMa) and Quadratus Lumborum (QL) muscles in individuals with lumbosacral transitional vertebra (LSTV) anomalies and to compare the muscle cross-sectional areas (CSA) of these individuals with a control group without LSTV. In this retrospective study, computed tomography (CT) images of 108 individuals aged between 18 and 65 years were analyzed. Participants were divided into two groups based on the presence of sacralization: 54 individuals with sacralization formed the "sacralization group," and 54 individuals without LSTV comprised the control group. Sacralization cases were subclassified according to the Castellvi classification. PMa and QL muscle CSAs were measured bilaterally at the L4 vertebral level using ImageJ software. Data were analyzed with SPSS version 22.0. The sacralization group exhibited significantly larger left PMa CSA (12.56 cm², P=0.001), left QL CSA (6.25 cm², P=0.004), and right QL CSA (6.48 cm², P=0.026) compared to the control group. Male participants had significantly larger PMa and QL CSAs than females (P<0.05). No significant relationship was found between Body Mass Index (BMI) and muscle CSA (p>0.05). However, a weak negative correlation was observed between age and PMa CSA (right PMa: P=0.013, r=-0.237; left PMa: P=0.007, r=-0.257). The observed increase in CSA of PMa and QL muscles in individuals with sacralization suggests that this anatomical variation may influence muscle morphology. These morphological changes could impact lumbar and pelvic function and should be considered during clinical evaluations.

Keywords

Sacralization , Lumbosacral transition , Muscle morphology , Psoas major , Quadratus lumborum

Ethical Statement

This study was approved by the Erciyes University Clinical Research Ethics Committee on May 10, 2023 (approval date: February 14, 2023, protocol code: 2023/330).

Supporting Institution

None

Thanks

This study was derived from the master’s thesis of Gamze Nur Koçer Kahrıman. Preliminary data were presented at the 16th International Scientific Research Congress (UMTEB).

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