Discussion
foraminal stenosis, pain, nerve entrapment, LSS, stenosis, NRS
NERVE ENTRAPMENT, DEGENERATIVE, LUMBAR SPINAL STENOSIS, STENOSIS
The main observation in this study was the association between severe foraminal stenosis of the lumbar foramina and significantly reduced chance of reaching a 30% improvement in the ODI score after microsurgical decompression for lumbar spinal stenosis. Severe foraminal stenosis at baseline reduced the probability to reach the targeted improvement by nearly fivefold when compared to having none to moderate foraminal stenosis. Significant association was also detected between severe foraminal stenosis and NRS back pain but not with NRS leg pain.The results are in accordance with considerations by Burton in 1981. Burton et al. emphasized that narrowing of the foraminal canal is an integral part of the degenerative process that leads to lumbar spinal stenosis. The group also postulated that nerve entrapment in the foraminal canal is an symptom aggressor [Regarding the prevalence of foraminal stenosis in patients referred to surgery for LSS, the earlier published data contains inhomogeneous study cohorts [Although the aspect of foraminal stenosis as an integrated part of the lumbar spinal stenosis entity is documented [A puzzling finding in the present study is the association between severe foraminal stenosis and outcome measured with NRS back pain while no such association was detected between severe foraminal stenosis and outcome measured with NRS leg pain. Published spinal literature suggests that decompression of the spinal nerve mainly helps radiating discomfort in patients with LSS [