Substantial Atrophy of the Psoas Muscle as Late Sequela of L2 Osteoporotic Fracture: a Case Report

Abstract

Osteoporotic vertebral fractures (OVFs) are considered benign and heal after 8-12 weeks. Nevertheless, up to one third of these patients will have persistent back pain, which may be complicated with neurologic deficit or paraplegia A unique unusual case of delayed onset of neurological complication of an osteoporotic vertebral fracture (OVF) in an elderly patient is reported. The patient presented with paraparesis due to isolated substantial atrophy of the psoas muscle 12 months after the initial fracture. The patient was investigated with imaging and nerve contacted studies. We suggest that psoas muscle atrophy can be determinant clinical sign to diagnose neurological compromise resulting from OVF, even if there is no other clinical indicators of spinal pathology.

FIGURE 1.

(A) Lateral plain lumbar spine radiograph obtained at three months after the injury demonstrates an L2 vertebral body fracture (thick arrow) with associated loss of height. (B) Lateral plain lumbar spine radiograph obtained nine months later remains unchanged, displaying no further loss of body height (thick arrow) and no development of kyphosis

FIGURE 2.

(A) Sagittal T2-weighted image displays the L2 vertebral fracture with resultant loss of body height and retropulsion (thick arrow). (B) Axial T2-weighted image in the L2-L3 vertebral disc level (as indicated by the white line seen in part A of the figure) demonstrates concomitant diffuse disc bulge, bilateral facet joint arthropathy, ligamentum flavum hypertrophy and central spinal canal stenosis. Cross-sectional area measurements of the psoas muscles (green lines bordering the perimeter of the psoas muscles) in the same level, show distinct atrophy of the left psoas muscle (white asterisk – area 2.447 cm²) when compared to the right psoas muscle (white dot – area 5.044 cm²). (C) T1-weighted coronal image also clearly demonstrates evident marked left-sided psoas muscle atrophy (black arrowheads) compared to the right psoas muscle (white arrowheads). (D) Sagittal T2-weighted image demonstrates left-sided foraminal stenosis (white arrow) in the L2-L3 level, which along with the aforementioned findings affects the ipsilateral exiting L2 nerve root, leading to left-sided psoas muscle atrophy.