Quantitative analysis of the correlation between preoperative cervical degeneration and postoperative heterotopic ossification after cervical disc replacement: minimum 10-year follow-up data

Abstract

OBJECTIVEThe authors aimed to identify factors that may be useful for quantifying the amount of degenerative change in preoperative patients to identify ideal candidates for cervical disc replacement (CDR) in patients with a minimum of 10 years of follow-up data.METHODSDuring the period from December 2003 to August 2008, 54 patients underwent CDR with a Bryan cervical disc prosthesis performed by the same group of surgeons, and all of the patients in this group with at least 10 years of follow-up data were enrolled in this retrospective analysis of cases. Postoperative bone formation was graded in radiographic images by using the McAfee classification for heterotopic ossification. Preoperative degeneration was evaluated in radiographs based on a quantitative scoring system. After univariate analysis, the authors performed multifactor logistic regression analysis to identify significant factors. To determine the cutoff points for the significant factors, a receiver operating characteristic (ROC) curve analysis was conducted.RESULTSStudy patients had a mean age of 43.6 years and an average follow-up period of 120.3 months. The patients as a group had a 68.2% overall incidence of bone formation. Based on univariate analysis results, data for patient sex, disc height, and the presence of anterior osteophytes and endplate sclerosis were included in the multivariate analysis. According to the analysis results, the identified independent risk factors for postoperative bone formation included disc height, the presence of anterior osteophytes, and endplate sclerosis, and according to a quantitative scoring system for degeneration of the cervical spine based on these variables, the ROC curve indicated that the optimal cutoff scores for these risk factors were 0.5, 1.5, and 1.5, respectively.CONCLUSIONSAmong the patients who were followed up for at least 10 years after CDR, the incidence of postoperative bone formation was relatively high. The study results indicate that the degree of degeneration in the target level before surgery has a positive correlation with the incidence of postoperative ossification. Rigorous indication criteria for postoperative ossification should be applied in patients for whom CDR may be a treatment option.

Effect of Facet Tropism on Postoperative Cervical Range of Motion After Single-Level Cervical Disc Arthroplasty

“… 19 , 44 Preoperative cervical degeneration, including osteophyte formation and facet joint degeneration, are considered as relative contraindications for disc replacement, because it may be related to poor postoperative ROM and heterotopic ossification (HO). 45 , 46 Although we excluded patients with severe facet joint degeneration not suitable for CDA, facet asymmetry may still be associated with some potential degeneration, which could also result in decreased ROM after CDA surgery. However, no significant progression of facet joint degeneration was observed during the 2-year follow-up period.…”

Diversity in Orthopaedic Surgery Medical Device Clinical Trials: An Analysis of the Food and Drug Administration Safety and Innovation Act

“…Although a significant number of class III devices were pertinent to spine surgery, only one performed a subgroup analysis that resulted in significant outcome differences between men and women (a greater proportion of women had heterotopic ossification after the implantation of the Bryan cervical disk arthroplasty). 8,28,29 It was hypothesized that this was a result of less spinal stability in women, possibly due to hormonal differences resulting in differences in skeletal growth and maturation. 8,28 In addition, both the Cormet and Conserve Plus Hip Resurfacing Systems were shown to have worse outcomes in women because of greater rates of revision surgery and implant failure, respectively.…”

The Effect of Preoperative Cervical Spondylosis on Heterotopic Ossification After Cervical Disc Replacement

“…The endplate sclerosis is distinguished among no apparent sclerosis, just detectable and definite sclerosis according to the degree of detectability. 10,17 The uncovertebral joint was assessed preoperatively using the coronal reconstruction computed tomography (CT) to identify osteophytes at the uncovertebral joint area. Facet joint degeneration was evaluated using a computed tomographic grading system reported by Park et al 11 (grade 1-4), with higher grade denoting more advanced degree of degeneration.…”

“…Wu et al 6 reported that the rate of HO formation was significantly higher in patients with spondylosis compared to that with soft-disc herniations. In recent years, several qualitative or quantitative studies confirmed the degree of degeneration in the surgical level was positively correlated with postoperative HO, [7][8][9][10] whilst some studies found preoperative degenerative changes exert no significant influence on the occurrence of HO. 11,12 However, few studies investigated the effect of all the components of cervical spondylosis on HO.…”