42. The impact of surgical decompression on neck pain outcomes in patients with degenerative cervical myelopathy: results from the multicenter prospective AOSpine studies

Abstract

BACKGROUND CONTEXT Surgery is increasingly recommended for the treatment of degenerative cervical myelopathy (DCM) as it effectively halts neurological progression and improves functional impairment, disability and quality of life. Although neck pain is a common complaint in patients with DCM, high-quality, prospective studies that summarize the incidence and severity of preoperative pain and evaluate the impact of surgery on pain outcomes are scarce. PURPOSE The objectives of this study are to (1) summarize the incidence and severity of preoperative pain in patients with DCM and (2) assess pain outcomes at 2 years following surgery. STUDY DESIGN/SETTING Ambispective cohort study. PATIENT SAMPLE From 2005 to 2011, 757 patients with DCM were enrolled in either the AOSpine North America or International study at 16 global sites. All patients underwent surgical decompression of the cervical spine and were followed up for 2 years postoperatively. A total of 664 patients had complete preoperative pain scores and 497 had pain outcomes at 2 years following surgery. Patients who reported no neck pain before surgery were excluded from the outcome analysis as they had no room for improvement. OUTCOME MEASURES Pain intensity subscore of the Neck Disability Index (NDI). METHODS As part of the NDI questionnaire, patients were asked to rate their neck pain as none, very mild, moderate, fairly severe, very severe or the worst imaginable. Frequencies and percentages were used to summarize the incidence and severity of preoperative pain and to describe pain outcomes at 2 years following surgery. Paired t-tests were conducted to determine differences in mean NDI pain intensity scores between baseline and 2 years postoperatively. Finally, the percentage of patients who exhibited an improvement, no change, or regression in pain scores was computed for each preoperative intensity group. Logistic regression was used to compute odds ratios with confidence intervals to determine whether pain improvement was associated with preoperative pain severity. RESULTS At baseline, 138 (20.8%) patients indicated they had no pain, whereas 134 (20.2%) rated their pain as very mild, 185 (27.9%) as moderate, 130 (19.6%) as fairly severe, 64 (9.6%) as very severe and 13 (2.0%) as the worst imaginable. At 2-year follow-up, 263 (67.6%) patients exhibited an improvement in their neck pain intensity score by at least one point, with 156 (40.1%) reporting no pain at all. The overall pain intensity score decreased from 2.3±1.0 to 1.1±1.2 (mean change: 1.1, 95% CI: 1.0 to 1.3, p-value CONCLUSIONS To our knowledge, this is the first multicenter, international study to quantify the preoperative incidence and severity of neck pain in patients with DCM and demonstrate significant improvements in neck pain at 2 years after surgery. Further studies are needed to evaluate important predictors of improvement in neck pain. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.