Potentialities of Diffusion Weighted MRI in the Assessment of the Degree of Adjacent Intervertebral Disc Degeneration: Rigid Lumbosacral Stabilization and Total Intervertebral Disc Arthroplasty

Abstract

Purpose: to evaluate the condition of adjacent intervertebral discs (IVD) after single level rigid lumbosacral stabilization and total arthroplasty by calculating IVD height index and apparent diffusion coefficient (ADC).Patients and methods. The study included 117 patients (64 women and 53 men) after rigid lumbosacral stabilization or total arthroplasty of the degenerative IVD at L5–S1 level. Values of ADC and height of the adjacent IVD were assessed prior to surgery, at discharge and in 6, 12, 24 and 36 months after surgical intervention.Results. The value of the height of the adjacent IVD in patients after rigid stabilization in the early postoperative period averaged 0.58±0.046, in 6 months – 0.58±0.044 and 0.52±0.037 in 36 months after surgery. In patients after total arthroplasty it made up 0.59±0.041, 0.60±0.038 and 0.56±0.02, respectively. Comparison of the adjacent IVD height indices showed significant difference starting from the 12th observation months (p<0.05). In group of patients after rigid stabilization the value of ADC made up 1547.7±231.4 mm2/s in the early postoperative period, 1314.5±117.9 mm2/s in 6 months and 1189.3±117.9 mm2/s in 36 months after surgery. In patients after total arthroplasty it was 1539.7±228.9 mm2/s, 1477.3±245.1 mm2/s and 1334.5±217.6 mm2/s, respectively. Statistically significant difference in ADC values between 2 groups of patients was noted in 6 months after surgery and later (p<0.05).Conclusion. Diffusion weighted MRI with ADC calculation is a modern noninvasive diagnostic method for early stages of adjacent IVD degeneration. In contrast to rigid lumbosacral stabilization, total IVD arthroplasty enables to delay slightly the degeneration of segments adjacent to the operated level.