Rib Hyperostosis as a Risk Factor for Poor Prognosis in Cervical Spine Injury Patients With Diffuse Idiopathic Skeletal Hyperostosis

Abstract

Study Design. Retrospective multi-center study. Objective. To identify the morphological features of costovertebral joints and ribs in surgically managed cervical injury patients with diffuse idiopathic skeletal hyperostosis (DISH) and to examine its impact on their vital prognosis. Summary of Background Data. Several reports have indicated that DISH is an independent risk factor for mortality after spinal fracture. The reason for the high mortality in cervical injury patients with DISH is unclear, although some reports have suggested a possible association between pulmonary complications and mortality. Methods. From 1999 to 2017, a total of 50 DISH patients (44 males) with cervical spine injuries who underwent spinal surgery were enrolled (average age 74 yrs). Prognosis and clinical risk factor data were collected; the morphological features of the patients’ costovertebral joints and ribs were evaluated with computed tomography. The influence of each proposed risk factor and thoracic morphological feature on mortality was tested with univariate and multivariate analyses. Results. The survival rate at 5 years after surgery was 52.3%. Nineteen (38%) patients died, and the most common cause of death was pneumonia (68%). Costovertebral bone excrescences and rib hyperostosis were found to be thoracic pathognomonic signs; their frequencies were 94% and 82%, respectively, and these conditions occurred in an average of 7.0 joints and 4.7 bones, respectively. The results of the log-rank test showed a significant difference in age, injury severity score (ISS), costovertebral bone excrescences, and rib hyperostosis. The results of age-adjusted multivariate analysis indicated that age (hazard ratio [HR] = 8.65, 95% confidence interval [CI] = 1.10–68.28, P = 0.041) and rib hyperostosis (HR = 3.82, 95% CI = 1.38–10.57, P = 0.010) were associated with mortality. Conclusion. Reduced chest wall mobility associated with rib hyperostosis in cervical spine injury patients with DISH leads to a poor prognosis. Level of Evidence: 3

Rib hyperostosis: a benign entity with suspicious imaging features

“…Our 2 cases differ in that the first patient was symptomatic and the second patient had metastatic prostate cancer. We also point out that although rib hyperostosis is a benign and frequently clinically insignificant finding, chest wall hypomobility in patients with diffuse idiopathic skeletal hyperostosis-associated rib hyperostosis has been shown to be a risk factor for poor prognosis after cervical spine injury [6] .…”

Prognostic Factors for Respiratory Dysfunction for Cervical Spinal Cord Injury and/or Cervical Fractures in Elderly Patients: A Multicenter Survey

“…DISH is an independent vital prognostic factor in patients with cervical SCI, and the main cause of death in patients with DISH is pneumonia. 23 Although the presence of thoracic spine DISH was not evaluated in this study, it is possible that thoracic spine DISH was included in the OPLL cases, which may have resulted in respiratory dysfunction. In SCI, the respiratory muscles are paralyzed, resulting in decreased ventilatory capacity and decreased ability to clear the upper airway.…”

Diffuse Idiopathic Skeletal Hyperostosis and Ankylosing Spondylitis: A Challenging Case and Review of the Literature

“…Sawakami et al described the morphological features of the costovertebral joints on computed tomography in a subpopulation of 50 DISH patients who required surgery for a cervical injury. Costovertebral joint osseous outgrowth and rib hyperostosis were recorded in 94% and 82% of the patients respectively, especially at the mid-thoracic level and with a predilection for the right side [33]. This predominant right-side involvement goes in line with that of vertebral ossifications and is also thought to result from the inhibitory effect of the pulsation of thoracic aorta on bone formation.…”