To identify the validity of the Straight leg raise and crossed straight leg raise in the diagnosis of Lumbar disc prolapse.

Systematic review of the literature. The Medline database was used (1966-09) using the search terms Lumbar disc prolapse /disc herniation/straight leg raise /crossed straight leg raise.

80 papers were identified from the search after duplicates had been removed. Of these, 6 abstracts were read and the full papers of 5 reviewed. Four papers scored highly on the STARD criteria and were used in the final review. Two systematic reviews (Vroomen et al, 1999; Deville et al, 2000) and two diagnostic studies (Majessi et al,2000; Vroomen et al, 2002). The review by Vroomen in 1999 identified 37 papers. Trials were included that used CT myelography, MRI or surgical findings as the gold standard. Deville identified 15 studies with the gold standard being findings at surgery. The diagnostic trial by Majessi et al (2008) and Vroomen et al (2002) both used MRI as the gold standard. The Diagnostic odds ratio for SLR ranged from 2.3-8.8 and for CSLR from 4.4 to 11.2. The most valid clinical test in the diagnosis of Lumbar disc prolapse is

the crossed straight leg raise. The straight leg raise has not been shown to have high validity