Cramp finding: can it be used as a new diagnostic and prognostic factor in lumbar disc surgery?

In this prospective study, the validity and the importance of a new finding (cramp finding) in the diagnosis and outcome after lumbar disc surgery were tested. The test is performed with the person in prone position. Against a forceful knee flexion, the examiner holds the leg with one hand and applies a force to overcome the knee flexion. The finding is positive if the examined person feels a disturbing cramp in the leg or thigh. The study was performed between October 1997 and December 1999. Besides the cramp finding, the classical disc herniation examination, including mechanical and neurological findings, magnetic resonance (MR) imaging tests, and laboratory findings were checked pre- and postoperatively. The positive cramp finding in the operated group was 72% (n=133) preoperatively and straight leg raising (SLR) test was positive in all of them. Cramp finding was positive in 70%, 52%, 34%, and 8% of patients postoperatively in the first, 3rd, 12th and 24th months, respectively. The presented finding appears to be as valuable as the SLR, and especially contralateral SLR, tests in lumbar disc surgery. Cramp finding is also important in outcome evaluation.