A systematic review of the passive straight leg raising test as a diagnostic aid for low back pain (1989 to 2000).
METHODS
A systematic review.


OBJECTIVE
This systematic review sought papers (January 1989-January 2000) on the passive straight leg raising test (PSLR) as a diagnostic component for low back pain (LBP) to identify, summarize, and assess developments in the test procedure, the factors influencing PSLR outcome, and the clinical significance of that outcome.


BACKGROUND
Previous studies suggested that the PSLR tractioned the sciatic nerve and that diminished leg elevation with reproduced pain indicated low lumbar intervertebral disc pathology.


METHODS
Searches on six computerized bibliographic databases identified publications written about the PSLR. Papers were excluded if they were published before January 1989, were non-English language papers, or employed either an active SLR or a PSLR for purposes other than LBP diagnosis. The references of qualifying papers (and the references of references) were searched. Contact with primary authors, and others known to be active in this field, was attempted.


RESULTS
The PSLR procedure remains unchanged. The influence of hip rotation during the PSLR was discussed without consensus. Biomechanical devices improved intra- and interobserver reliability and so increased test reproducibility. Hamstrings were found to have a defensive role in protecting nerve roots by limiting PSLR range in cases of nerve root inflammation. A small diurnal variation in the PSLR may imply a poorer prognosis. A positive PSLR at 4 months after lumbar intervertebral disc surgery predicted poor reoperative outcome, and a negative 4-month PSLR predicted excellent outcome. The influence of psychosocial factors was not discussed, neither was the diagnostic significance of a negative PSLR outcome.


CONCLUSIONS
There remains no standard PSLR procedure, no consensus on interpretation of results, and little recognition that a negative PSLR test outcome may be of greater diagnostic value than a positive one. The causal link between LBP pathology and hamstring action remains unclear. There is a need for research into the clinical use of the PSLR; its intra- and interobserver reliability; the influences of age, gender, diurnal variation, and psychosocial factors; and its predictive value in lumbar intervertebral disc surgery.
Rebain
Richard
R
University of Ulster, Rehabilitation Sciences Research Group, Newtownabbey, County Antrim, Northern Ireland.
Baxter
G David
GD
McDonough
Suzanne
S
D000367:Age Factors; D003943:Diagnostic Techniques, Neurological / Q000592:standards / Q000706:statistics & numerical data; D006801:Humans; D007866:Leg / Q000503:physiopathology*; D017116:Low Back Pain / Q000175:diagnosis* / Q000503:physiopathology*; D015588:Observer Variation; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012737:Sex Factors