Quality of life improved with surgical treatment for cervical myelopathy

The researchers reported a significant improvement in all outcome parameters from baseline to 1 year.

Surgical treatment for cervical spondylotic myelopathy led to improvements in health-related quality of life measures, according to data presented at the North American Spine Society 24th Annual Meeting in San Francisco.

Michael Fehlings, MD, PhD, FRCSC, FRCS, professor in the division of neurosurgery and Krembil chair in neural repair and regeneration at the University of Toronto in Canada, and his colleagues found that surgical treatment for cervical spondylotic myelopathy (CSM) was associated with improved generic and disease-specific health-related quality of life measures at 1 year postoperatively. These improvements were sustained at 2 years postoperatively.

Fehlings and colleagues enrolled 304 patients with clinically confirmed CSM into the prospective, controlled cohort study. Patients were treated at 13 North American sites. At 1 year, the researchers achieved 82.4% follow-up, and they have obtained 2-year follow-up results from 127 patients.

Surgical team preference

Patients were treated based on surgical team preference and underwent either anterior (discectomy/corpectomy and instrumented fusion) or posterior (laminectomy and fusion or laminoplasty) techniques. According to Fehlings, surgeons tend to select certain patients for each technique.

“This counters some of the arguments that have been raised against surgical treatment, which have suggested that long-term results have indicated a decline in function.” — Michael Fehlings, MD, PhD, FRCSC, FRCS

“Anterior techniques are used in patients who are about a decade younger, who have less impairment as judged by the modified Japanese Orthopedic Assessment (JOA) Scale and the Nurick scores, and who have a more focal pathology,” Fehlings said. These differences were taken into account in the analysis.

The researchers reported a statistically and clinically significant improvement in all outcome parameters from baseline to 1 year (P < .01). Modified JOA scores improved from 13.16 at baseline to 15.77 at 1 year and 16.24 at 2 years (P < .001). Scores on the Neck Disability Index improved from 39.06 at baseline to 27.52 at 1 year and 27.51 at 2 years (P<.001).

Counters arguments

The Nurick scores also improved, from 4.07 at baseline to 2.53 at 1 year and 2.47 at 2 years (P < .001). “This counters some of the arguments that have been raised against surgical treatment, which have suggested that long-term results have indicated a decline in function,” Fehlings said.

Results also suggested a time-dependent impact on the outcomes, a finding that surprised the researchers. All patients showed improvement in myelopathy symptoms, but “patients with briefer periods of impairment — of 6 months or less — showed the optimal results,” Fehlings said.

The researchers also observed improvements on the physical and mental health component scores of the SF-36, which Fehlings said indicates an improvement in quality of life comparable to that seen with hip arthroplasty. – by Tina Dimarcantonio

Reference:

• Fehlings M, Kopjar B, Yoon ST, et al. Surgical treatment for cervical spondylotic myelopathy: One-year outcomes of the AOSpine North America multicenter prospective study of 301 patients. Presented at the North American Spine Society 24th Annual Meeting. Nov. 10-14, 2009. San Francisco.
• Michael Fehlings, MD, PhD, FRCSC, FRCS, Professor in the Division of Neurosurgery and Krembil Chair in Neural Repair and Regeneration, can be reached at Michael.fehlings@uhn.on.ca.

Fehlings et al have presented encouraging preliminary results of an important study investigating outcomes of surgical treatment for cervical spondylotic myelopathy. This multicenter prospective study, sponsored by AOSpine North America, addresses critical basic questions regarding the efficacy of surgery and the durability of successful results following surgery.

Although the need for surgical decompression of the spinal cord in patients with severe or progressive myelopathy and significant cord compression is not particularly controversial among spine surgical specialists, there remains a glaring paucity of good quality clinical evidence proving that such surgery is indeed effective. In fact, a Cochrane review published in January sought to answer the specific questions of whether surgery leads to superior results compared with nonoperative care and whether the timing of surgery had any impact on outcomes. Based on the available medical literature, this review concluded that there was insufficient evidence from two fairly small prospective randomized trials to answer either question. The authors, Nikolaidis et al, concluded that, “It is unclear whether the short-term risks of surgery are offset by long-term benefits.”

Unfortunately, although the results reported by Fehlings et al suggest that patients do experience significant improvement in multiple outcome measures following surgical treatment and that such improvement appears sustained through 2 years, a nonoperative control group is missing and prevents any conclusion being drawn regarding the relative improvement surgical patients may or may not enjoy compared with similar patients who elect nonoperative care. Therefore, for certain academics and policymakers, if not for spine surgical specialists, this study will likely prove less than satisfying.

An interesting aspect of the study is the authors’ report that patients with 6 months or shorter duration of symptoms experienced superior outcomes following surgery compared with patients suffering a longer period of symptoms. Dr. Fehlings confirmed that multivariate analysis considered both patient age and severity in this calculation. The apparent implication of this finding is that surgery, if performed, should be accomplished in a timely fashion, at least within 6 months of symptom onset. However, the practical application of such a recommendation remains quite problematic, given the subtle initial presentation of myelopathy in a majority of cases and the absence of clear-cut diagnostic criteria for mild myelopathy. There are also concerns regarding the medico-legal implications if such a recommendation is made. At this time, the spine surgical community seems comfortable with the notion that an indefinite period of observation is perfectly reasonable in patients with apparently stable mild myelopathy.

– David H. Kim, MD
Assistant Clinical Professor of Orthopedic Surgery, Tufts University School of Medicine
Director of Medical Education, New England Baptist Hospital