Article révisé par les pairs
Résumé : Introduction: Segmental instability of the spine caused by the decreased height of intervertebral discs is one of the major causes of chronic low back pain affecting 70-80% of the adult population. The decrease in height is due to degenerative lesions induced by vertical compression overload of the disc. Objective: A preliminary study was performed to determine if disc degeneration due to overload could be stopped. We hypothesized that disc distraction during fusion surgery from posterior approach could reduce the pressure on the discs, degeneration could be stopped, and perhaps the function could be restored. Methods: To characterize the condition of the discus, we used the determination glycosaminoglycan content, which is responsible for the disc-bound water content and thus for ensuring its elasticity. The use of gadolinium contrast agent in MRI (dGEMRIC) is an accepted method for determining the glycosaminoglycan content of the intervertebral disc, as the concentration of absorbed contrast agent is inversely proportional to the number of glycosaminoglycans in the intervertebral discs. In addition to pre- and postoperative dGEMRIC data, we examined disc height, lumbar lordosis, visual analog pain scale, and the Oswestry Disability Index. Results: All patients underwent monosegmental fusion following posterior distraction of the affected segment due to segmental instability. During the surgeries, lumbar lordosis did not decrease despite posterior distraction. The heights of the discus increased by an average of 3 mm, the pain decreased, and the Oswestry Disability Index improved. In the dGEMRIC studies, an average of 309.18 units/cm2 of gadolinium accumulated in the discs before surgery, which decreased postoperatively to 174.43 units/cm2. All changes were significant at the p = 0.05 significance level. Conclusion: The trend of our preliminary results suggests that increasing the height of the discs can reduce the hydrostatic pressure in the discs, resulting in an increase in the amount of glycosaminoglycans, which can stop the degeneration of the discs and also initiate regeneration processes.