ABSTRACT
BACKGROUND: The X-ray 9-point grading system is established based on cervical disc degeneration and its suitability for evaluation of lumbar disc degeneration has not been validated. OBJECTIVE: To investigate the feasibility of the evaluation of lumbar intervertebral disc degeneration using the 9-point grading system with X-ray, and to explore its clinical application value. METHODS: The correlation between 9-point grading system and Pfirrmann system was statistically analyzed. Magnetic resonance imaging (MRI) and X-ray images of 172 cases with lumbar disc degeneration or simple lumbago, who were treated in the Shanghai Changzheng Hospital from June 2013 to June 2016, were retrospectively analyzed. The MRI scores of lumbar disc degeneration were evaluated according to Pfirrmann standard, and the X-ray scores were evaluated according to 9-point grading system. The two groups of scores were respectively analyzed by the correlation and regression tests via Spearman rank sum test with SPSS software. RESULTS AND CONCLUSION: (1) MRI scores (the independent variable X): 2 cases scored 1; 8 cases scored 2; 55 cases scored 3; 84 cases scored 4; 23 cases scored 5. X-ray scores (the dependent variable Y): 2 cases scored 0; 6 cases scored 1; 21 cases scored 2; 43 cases scored 3; 40 cases scored 4; 26 cases scored 5; 16 cases scored 6; 8 cases scored 7; 7 cases scored 8; 3 cases scored 9. (2) The Spearman correlation test showed that significant positive correlation was found between Pfirrmann system and 9-point grading system (P <0.01). Significance test of correlation coefficient proved that there was significant linear correlation between Pfirrmann system and 9-point grading system. Further regression analysis showed the linear regression between Pfirrmann system and 9-point grading system. (3) These findings suggested that Pfirrmann system and X-ray 9-point grading system had a good consistency in evaluating lumbar disc degeneration. As a scientific, fast and effective evaluation method, the X-ray 9-point grading system has a certain reference value in the diagnoses of lumbar degenerative diseases.