1. Linton SJ, Halldén K. Can we screen for problematic back pain? A screening questionnaire for predicting outcome in acute and subacute back pain. Clin J Pain. 1998;14:209–15.
2. Anderson R, Meeker WC, Wirick BE, et al. A metaanalysis of clinical trials of spinal manipulation. J Manip Physiol Ther. 1992;15:181–94.
3. Manchikanti L, Abdi S, Atluri S, et al. An update of comprehensive evidence-based guidelines for interventional techniques of chronic spinal pain: part II: guidance and recommendations. Pain Physician. 2013;16:S49–S283.
4. Goebert HW Jr, Jallo SJ, Gardner WJ, et al. Painful radiculopathy treated with epidural injections of procaine and hydrocortisone acetate: results in 113 patients. Anesth Analg. 1961;40:130–4.
5. Wang A, Pilgram TK, Gilula LA. Immediate complications and pain relief associated with 296 fluoroscopically guided thoracic foraminal nerve blocks. AJR Am J Roentgenol. 2011;197:1410–6.