case_images: PMC7203533_01
case_images: A 28-year-old woman who presented with low back pain for a month without neurological symptoms: (a) axial and (b) coronal T1-weighted images of the pelvis show congenital absence of the left piriformis muscle (yellow arrows point to the expected location).
case_images: SAJR-24-1838-g001.jpg
case_images: PMC7203533_01_SAJR-24-1838-g001.jpg
case_images: F0001
case_images: Given the history of perineal discomfort, MR neurography of the pelvis was subsequently performed to evaluate the pudendal nerve and demonstrated absence of the left piriformis muscle (Figure 1).
case_images: (a) Axial T2 fat-saturated (b) and coronal short tau inversion recovery images again reveal the same findings.
case_images: SAJR-24-1838-g002.jpg
case_images: PMC7203533_01_SAJR-24-1838-g002.jpg
case_images: F0002
case_images: The sciatic nerve and lumbosacral plexuses were normal in configuration and signal intensity with no signs of neuritis (Figure 2).