Vertebral bone density in Hounsfield units as a predictor of interbody non-union and implant subsidence in lumbar circumferential fusion

Objective. To determine the values of Hounsfield units (HU) lumbar vertebrae predicting unsatisfactory radiological results circumferential interbody fusion at level. Material and Methods. The data patients who underwent a single-level decompression stabilization intervention L4–L5 or L5–S1 level for degenerative diseases spine were analyzed. CT images assessed before surgery with measurement HU vertebral bodies level, as well one year after to evaluate degree block formation subsidence cage. Three groups distinguished: formed bone without cage (control group), failed subsidence. Results. study presents 257 patients. incidence non-union was 32.3 % (83/257), – 43.6 (112/257). proportion reduced mineral density (BMD) 26.1 (67/257). Patients had higher ODI scores (p = 0.045 p 0.050, respectively) compared controls. presence failure is associated BMD < 0.05), score 0.05). According ROC analysis, threshold determined equal 127 HU, 136 142 L4, L5, S1 bodies, respectively. Upon reaching these values, risk combination increases significantly 0.022). Conclusions. have less satisfactory clinical outcomes. S1, respectively, are advisable use in practice predict lower levels.