Heterotopic Ossification Following Decompression and Interspinous Dynamic Stabilization for Treating Lumbar Degenerative Disease Based on Minimum Follow-Up of Five Years and X-ray Imaging

摘要

Objective: Hetertopic ossiofication (HO) was considered one of the main adverse events following lumbar decompression and could negatively affect these patients' daily activity. However, there is still a lack of evidence to assess the association between the incidence of HO atsurgical segment and clinical outcomes following the implantation of a Coflex? device. The objective of this study is determine the association between the incidence of HO and clinical outcomes following implantation of a Coflex? device based on X-ray imaging.Methodology: One hundred sixty-nine consecutive patients who underwent decompression and implantation of a Coflex? device from December 2007 to January 2014 were studied. A logistic regression analysis was used to analyze complications and development of HO. Spearman'srank correlation coefficient was used to analyze the correlation between clinical results and the incidence of HO based on X-ray imaging. Results: All patients showed improvement from baseline in clinical outcomes at all time points up to 5 years post-operation (all p = 0.000).Preoperative range of motion (ROM) of operated segment had a positive relationship with the incidence of HO (r = 0.194, p = 0.012). No correlation exists between the incidence of HO and clinical outcomes. The odds ratio (OR) for development of complications in patients with Pfirrmanndisc degeneration classification grades III and IV compared to those with grades 0, I and II was 3.003 (p = 0.005, 95% confidence interval, 1.621–34.195). In addition, the OR for the incidence of HO in the large ROM of the surgical segment compared to that in the normal/smallROM segment was 21.670 (p = 0.001, 95% confidence interval, 21.137–22.280). Conclusions: Our findings provide evidence that high Pfirrmann disc degenerative classification grades and a large ROM of the surgical segment were the main risk factors for complications and developmentof HO, respectively.