Lumbar Foraminal Stenosis Etiology

Lumbar foraminal stenosis (LFS) is one of the most frequent forms of lumbar degenerative spondylosis (LDS), a late consequence of intervertebral disc degeneration (IVD) and considered a wear-and-tear phenomenon that is at least partially age-related. The narrowing of the intervertebral space leads to secondary hypertrophy of the intervertebral joints as a reaction to overload, ligamentous overgrowth, and a reduction in intervertebral foramen diameter. This chain reaction is the main reason for nerve root impingement and distorted neurodynamics that lead to mixed pain in advanced spondylosis (axial and radicular pain) ¹⁾.

Lumbar Foraminal Stenosis can develop as a result of progressing Degenerative spine disease due to aging, causing disc height loss of an intervertebral disk, osteoarthritic changes in the facet joints, cephalad subluxation of the superior articular process of the inferior vertebra, and buckling of the ligamentum flavum or protrusion of the annulus fibrosus ²⁾ may lead to segmental instability and subsequent central/foraminal stenosis secondary to ligamentum flavum hypertrophy and osteophyte formation.

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Urits I, Burshtein A, Sharma M, Testa L, Gold PA, Orhurhu V, Viswanath O, Jones MR, Sidransky MA, Spektor B, Kaye AD. Low Back Pain, a Comprehensive Review: Pathophysiology, Diagnosis, and Treatment. Curr Pain Headache Rep. 2019 Mar 11;23(3):23. doi: 10.1007/s11916-019-0757-1. PMID: 30854609.

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Hasegawa T, An HS, Haughton VM, Nowicki BH. Lumbar foraminal stenosis: critical heights of the intervertebral discs and foramina. A cryomicrotome study in cadavera. J Bone Joint Surg Am. 1995 Jan;77(1):32-8. PMID: 7822353.