1. Manchikanti L. Epidemiology of low back pain. Pain Physician. 2000;3(2):167–92.
2. Keshari KR, Lotz JC, Link TM, et al. Lactic acid and proteoglycans as metabolic markers for discogenic back pain. Spine. 2008;33(3):312–7.
3. Coté P, Cassidy JD, Carroll L. The Saskatchewan Health and Back Pain Survey. The prevalence of neck pain and related disability in Saskatchewan adults. Spine. 1998;1(23):16789–98.
4. Braithwaite IJ, White A, et al. Vertebral end-plate (Modic) changes on lumbar spine MRI: correlation with pain reproduction at lumbar discography. Eur Spine J. 1998;7:363–8.
5. Kokkonen S, Kurunlahti M, Tervonen O, et al. Endplate degeneration observed on magnetic resonance imaging of the lumbar spine. Spine. 2002;27(20):2274–8.