160. Anterior cervical discectomy and fusion vs cervical disc replacement for cervical spondylotic myelopathy: An MCID comparison

Abstract

<h3>BACKGROUND CONTEXT</h3> Comparative studies of patients with cervical spondylosis treated with either cervical disc replacement (CDR) or anterior cervical discectomy and fusion (ACDF) are sparse in number. Previous studies have demonstrated good outcomes in patients undergoing CDR with moderate cervical spondylosis involving the disc, uncovertebral or facet joints. <h3>PURPOSE</h3> To compare clinical outcomes in patients with moderate cervical spondylosis undergoing CDR vs, the gold standard, ACDF. <h3>STUDY DESIGN/SETTING</h3> Retrospective review of prospectively collected data. <h3>PATIENT SAMPLE</h3> Patients who underwent one or 2-level CDR or ACDF with moderate cervical spondylosis, quantified using a validated grading scale, were identified, and prospectively collected data was retrospectively reviewed. <h3>OUTCOME MEASURES</h3> Neck Disability Index (NDI), VAS-Neck, VAS-Arm and PROMIS Physical Function (PROMIS-PF) computer adaptive test score. <h3>Methods</h3> Patients who underwent one or two-level CDR or ACDF with moderate cervical spondylosis, quantified using a validated grading scale, were identified, and prospectively collected data was retrospectively reviewed. Cervical spondylosis was graded by assessing disc height, facet arthrosis, and uncovertebral joint degeneration. Each of these characteristics was given a score of 0, 1 or 2 with increasing scores correlating with more severe disease. Demographic, operative, and cervical spondylosis grades and achievement of MCID for each PRO was analyzed and compared between the two groups. <h3>Results</h3> A total of 66 patients were included in the present study, of which 35 (53%) were treated with CDR and 31 (47%) with ACDF. Average follow up was 15.5 months. Patients treated with ACDF were significantly older (58.7 vs 43.0 years-old, P<0.01). Other demographic variables were similar between the two groups. There were no significant differences in operative time, level of surgery, intraoperative complications, inpatient complications and length of stay between the two groups. The preoperative cervical spondylotic grade was similar between the two groups (1.8 vs 2.2, P=0.27). At final follow-up, patient reported outcomes improved significantly compared to preoperative values in both treatment groups. There was no significant difference in the absolute value for each patient reported outcome at final follow-up between the two groups. In the CDR group, greater than 70% of patients achieved the MCID in all four patient reported outcomes assessed; in the ACDF group, greater than 50% of patients achieved the MCID in all four patient reported outcomes assessed. There was no significant difference in the percentage of patients achieving the MCID when comparing CDR to ACDF. <h3>Conclusions</h3> The results of the present study demonstrate that patients with moderate cervical spondylosis treated with CDR reported similar postoperative patient reported outcomes to those treated with ACDF. The use of CDR in patients with spondylosis of the uncovertebral joint, facet joint, or disc space height loss may result in similar outcomes compared to ACDF treated patients, while preserving motion and avoiding the biologic demand of obtaining a fusion across the involved cervical levels. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.