Do Racial Differences Affect Surgical Outcomes in Patients with Degenerative Cervical Myelopathy?: Results from the Prospective Multicenter AOSpine International Study on 479 Patients. Issue 1 (April 2016)

• Record Type: Journal Article
• Authors: Nagoshi, Narihito; Tetreault, Lindsay; Nakashima, Hiroaki; Nouri, Aria; Fehlings, Michael
• Is Part Of: Global spine journal. Volume 6:Issue 1(2016)Supplement
• Page Start: s-0036-1582786
• Page End: s-0036-1582786
• Publication Date: 2016-04
• Subjects: Spine -- Diseases -- Periodicals; Spine -- Diseases -- Treatment -- Periodicals; Spine -- Abnormalities -- Periodicals; Spine -- Surgery -- Periodicals; 616.73
• DOI: 10.1055/s-0036-1582786
• Languages: English
• ISSNs: 2192-5682

Abstract

Introduction: Degenerative cervical myelopathy (DCM) is the most common disease of the cervical spine in the elderly worldwide, and surgical decompression is a widely accepted procedure to prevent neurological deterioration. Although racial background affects clinical outcomes in various medical conditions and diseases, few studies have evaluated the impact of racial differences on surgical outcome after DCM. The purpose of this study is to comprehensively evaluate whether racial background is an independent predictor of surgical outcomes for DCM. Material and Methods: A total of 479 patients with symptomatic DCM were prospectively enrolled in the AOSpine CSM-International study at 16 global sites. Patients' functional status were evaluated using the modified Japanese Orthopedic Assessment scale, the Nurick score, the Neck Disability Index, and the Short- Form 36 (SF-36) Health Survey. Improvements in functional status and QOL were assessed between baseline and 24-months follow-up. A mixed model analytic approach was used to evaluate differences in surgical outcome between races, while controlling for relevant baseline characteristics and surgical factors. Results: Of the 479 DCM patients, 324 (67.64%) and 106 (22.13%) were Caucasians and East Asians, respectively. Other races were excluded as there were too few patients to conduct separate analyses. There was no difference in the incidence of ossification of the posterior longitudinal ligament (OPLL) between the two races; however a greater percentage of Caucasians in India (46.15%) and Turkey (41.38%) exhibited OPLL than Caucasians at sites in other regions. The frequency of spondylosis was significantly higher in Caucasians ( p < 0.0001). Caucasians had a significantly longer duration of symptoms ( p = 0.0002), a greater number of co-morbidities ( p = 0.0288), and a lower preoperative score on the SF-36 Physical Component Score ( p = 0.0002) than East Asians. At 24-months postoperative, there were no significant differences in functional status or QOL between East Asian and Caucasian patients, after adjusting for variations in baseline characteristics, surgical preferences and disease causation. In addition, rates of perioperative complications were not significantly difference between the races ( p = 0.261). Conclusion: Although the frequency of subcategories of DCM differs between racial backgrounds, this does not affect surgical outcomes for DCM. Decompressive surgery for DCM is equally safe, and provides comparable functional gains both in Caucasians and East Asians. Although the prevalence of OPLL in East Asians has generally been thought to be higher than amongst Caucasians, our findings indicate that individuals from India and Turkey may also be at a high risk of OPLL development.