Lumbar dural sac cross sectional area

Studies have evaluated the associations between the dural sac cross sectional area (DSCSA) on MRI and the symptoms of LCCSS ¹⁾ ²⁾.

Smaller DSCSA was directly related to lower health-related quality of life, more back and leg pain, and shorter walking distances before claudication ³⁾. DSCSA was proposed as the most specific and sensitive morphologic parameter predicting the absence or presence of leg pain ⁴⁾. Another study demonstrated that the ratio between the DSCSA of the vertebral body can be used as a diagnostic marker to predict the occurrence of LCCSS ⁵⁾. Narrow DSCSA was significantly associated with the presence of low back pain after adjustment for body mass index, age, and sex ⁶⁾.

Narrowing of the lumbar dural sac cross sectional area (DSCSA) and spinal canal cross-sectional area (SCCSA) have been considered major causes of lumbar central canal spinal stenosis (LCCSS). DSCSA and SCCSA were previously correlated with subjective walking distance before claudication occurs, aging, and disc degeneration. DSCSA and SCCSA have been ideal morphological parameters for evaluating LCCSS.

To evaluate lumbar central canal spinal stenosis (LCCSS) patients, pain specialists should more carefully investigate the dural sac cross-sectional area (DSCSA) than spinal canal cross-sectional area (SCCSA) ⁷⁾.

Schonstrom et al. showed that neurogenic claudication due to LSS was better defined by the cross-sectional area (CSA) of the dural sac, but that the CSA of the lumbar vertebral canal was unrelated to that of the dural sac ⁸⁾. From in vitro ⁹⁾ and in situ ¹⁰⁾ studies, the authors postulated that constrictions above the critical size 70 to 80 mm2 would be unlikely to cause symptoms and signs of cauda encroachment. Subsequently, conflicting results have been published concerning the relationship between symptom severity and dural CSA. Even after axial loading, no statistically significant correlations were found in some studies ¹¹⁾. However, in another study, the use of the minimal CSA of the dural sac in central stenosis was found to be correlated with neurogenic claudication assessed measuring the maximum tolerated walking distance ¹²⁾.

¹⁾

Abbas J, Hamoud K, Masharawi YM, et al. Ligamentum flavum thickness in normal and stenotic lumbar spines. Spine (Phila Pa 1976) 2010;35:1225–30.

²⁾

Okuda T, Baba I, Fujimoto Y, et al. The pathology of ligamentum flavum in degenerative lumbar disease. Spine (Phila Pa 1976) 2004;29:1689–97.

³⁾

Ogikubo O, Forsberg L, Hansson T. The relationship between the cross-sectional area of the cauda equina and the preoperative symptoms in central lumbar spinal stenosis. Spine (Phila Pa 1976) 2007;32:1423–8

⁴⁾

Pneumaticos SG, Hipp JA, Esses SI. Sensitivity and specificity of dural sac and herniated disc dimensions in patients with low back-related leg pain. J Magn Reson Imaging 2000;12:439–43.

⁵⁾

Premchandran D, Saralaya VV, Mahale A. Predicting lumbar central canal stenosis—a magnetic resonance imaging study. J Clin Diagn Res 2014;8:RC01–4.

⁶⁾

Iwahashi H, Yoshimura N, Hashizume H, et al. The association between the cross-sectional area of the dural sac and low back pain in a large population: the wakayama spine study. PLoS One 2016;11:e0160002.

⁷⁾

Lim YS, Mun JU, Seo MS, Sang BH, Bang YS, Kang KN, Koh JW, Kim YU. Dural sac area is a more sensitive parameter for evaluating lumbar spinal stenosis than spinal canal area: A retrospective study. Medicine (Baltimore). 2017 Dec;96(49):e9087. doi: 10.1097/MD.0000000000009087. PubMed PMID: 29245329; PubMed Central PMCID: PMC5728944.

⁸⁾

Schonstrom NS, Bolender NF, Spengler DM. The pathomorphology of spinal stenosis as seen on CT scans of the lumbar spine. Spine (Phila Pa 1976). 1985 Nov;10(9):806-11. PubMed PMID: 4089655.

⁹⁾

Schönström N, Bolender NF, Spengler DM, Hansson TH. Pressure changes within the cauda equina following constriction of the dural sac. An in vitro experimental study. Spine (Phila Pa 1976). 1984 Sep;9(6):604-7. PubMed PMID: 6495030.

¹⁰⁾

Schönström N, Hansson T. Pressure changes following constriction of the cauda equina. An experimental study in situ. Spine (Phila Pa 1976). 1988 Apr;13(4):385-8. PubMed PMID: 3406845.

¹¹⁾

Lohman CM, Tallroth K, Kettunen JA, Lindgren KA. Comparison of radiologic signs and clinical symptoms of spinal stenosis. Spine (Phila Pa 1976). 2006 Jul 15;31(16):1834-40. PubMed PMID: 16845360.

¹²⁾

Ogikubo O, Forsberg L, Hansson T. The relationship between the cross-sectional area of the cauda equina and the preoperative symptoms in central lumbar spinal stenosis. Spine (Phila Pa 1976). 2007 Jun 1;32(13):1423-8; discussion 1429. PubMed PMID: 17545910.