Importance of intervertebral disc size in low back pain.

AIM To compare two anthropometrical methods for measuring the intervertebral disc size with computer tomography measurements and to develop a new anthropometric method for calculating intervertebral disc area. METHODS Intervertebral disc size was measured using computer tomography and two anthropometric methods (Colombini and modified Colombini) in a sample of 40 subjects. The new calculation for intervertebral disc size was developed and used in a sample of male bus drivers with (n=65) and without (n=30) anamnestic low back pain to asses clinical usefulness. RESULTS The modified anthropometric method for intervertebral disc size assessment correctly predicted intervertebral disc size in 89% of the cases and the determination error was diminished to an average of 4.1% for level L4-L5 and 4.4% for level L5-S1. The average size of the intervertebral discs in 65 subjects with anamnestic lower back problems was significantly smaller than in the control group of 30 subjects having no such problems (p<0.001). CONCLUSION The use of the presented formulas for the calculation of the intervertebral disc in L4-5 and L5-S1 areas from the data obtained by simple anthropometrical measurements is sufficiently reliable and accurate. The method is economical and harmless.