According to results in a recently published study, determining differences in the foraminal spine nerve angle between the symptomatic and asymptomatic sides of greater than 10° is a simple and complimentary method for diagnosing extraforaminal entrapment.
Researchers analyzed 70 consecutive patients who underwent unilateral L5-S1 extraspinal canal decompression for extraforaminal entrapment (e-FE) or 4/5 intraspinal canal decompression for lumbar spinal canal stenosis. All patients had unilateral L5 radiculopathy and were split into two separate groups. Group A consisted of 21 patients with unilateral L5-S1 e-FE and Group B consisted of 49 patients with intraspinal canal L4-L5. A third group of 44 patients comprised the control group, which included only patients with back pain without leg radiculopathy.
Every patient underwent oblique coronal T2-weighted imaging (OC-T2WI), and the researchers examined and compared the differences in the FSN angle of the fifth lumbar spinal nerve between the symptomatic and asymptomatic sides (ΔFSN angle) between the study groups.
The ΔFSN angle was 17° in Group A, 4.8° in Group B and 6.4° in Group C, with no statistically significant differences observed in any of the groups.
The researchers noted the cutoff value of the ΔFSN angle (10°) was indicative of diagnostic accuracies of 94% and 91% for sensitivity and specificity and of 93% and 95%, respectively. It was concluded finding the differences between the ΔFSN angle was an accurate method for diagnosing lumbar e-FE with high sensitivity and specificity. – by Robert Linnehan.
Disclosure: The researchers report no relevant financial disclosures.