1. Manchikanti L, Boswell MV, Singh V, et al. Comprehensive evidence-based guidelines for interventional techniques in the management of chronic spinal pain. Pain Physician. 2009;12:699–802.
2. Huntoon MA. Ultrasound in pain medicine: advanced weaponry or just a fad? Reg Anesth Pain Med. 2009;34:387–8.
3. el-Khoury GY, Ehara S, Weinstein JN, Montgomery WJ, Kathol MH. Epidural steroid injection: a procedure ideally performed with fluoroscopic control. Radiology. 1988;168:554–7.
4. American College of Occupational and Environmental Medicine. Low back disorders. Occupational Medicine Practice Guidelines. 2nd ed. Elk Grove Village, IL: American College of Occupational and Environmental Medicine. 2008 [chapter 12].
5. Manchikanti L, Singh V, Derby R, et al. Review of occupational medicine practice guidelines for interventional pain management and potential implications. Pain Physician. 2008;11:271–89.