175. Intraoperative alignment goals for severe cervical deformity to achieve optimal improvements in health-related quality of life measures

Abstract

BACKGROUND CONTEXT Patients with severe cervical deformity (CD) often have profound deficits in numerous activities of daily living. Association between health status and postoperative radiographic goals is difficult to quantify. PURPOSE Investigate the radiographic characteristics of patients who achieved optimal HRQOLs following surgery for CD. STUDY DESIGN/SETTING Retrospective review of prospective CD database. PATIENT SAMPLE Forty adult CD patients (C2-C7 Cobb>10°, CL>10°, cSVA>4cm, or CBVA>25°). OUTCOME MEASURES Health-related-quality of life (HRQL) scores, radiographic alignment. METHODS Surgical patients with severe CD were isolated based upon a previously presented combination of preop cSVA, T1 slope, maximum focal kyphosis in extension, C2 slope in extension, and number of kyphotic levels in extension. Those with available preop and 1-year postop HRQL data were included. Based on previous study, patients were grouped into 3 distinct patterns of CD: focal deformity (FD), flatneck (FN=large TS-CL and lack of compensation), or cervicothoracic (CT). Postoperative outcomes were defined as “good” if a patient had >2 of the 3 following criteria (1) NDI 2 points from baseline. Within each distinct deformity group, patients with good outcomes were compared to those with poor outcomes (ie, not meeting the criteria for good) for differences in demographics, HRQL scores, and alignment, via chi-squared or student's t-tests. RESULTS Overall, 83/153 patients met the criteria of severe CD and 40 patients had complete 1-year follow-up of clinical/radiographic data. Patient breakdown by deformity pattern was as follows: CT (N=13), FN (N=17), and FD (N=17), with 7 patients meeting criteria for both FD and FN deformities. Within the FD cohort, maximal focal kyphosis (ie, kyphosis at one level) was better corrected in patients with a “good” outcome (p = 0.03). In the FN cohort, patients who went on to have “good” outcomes presented with worse horizontal gaze (McGregor slope 21° vs 6°, p=0.061) and cSVA (72 mm vs 60 mm, p=0.030). “Good” outcome FN patients showed significantly greater postop correction of horizontal gaze (−25° vs −5°, p = 0.031). In the CT cohort, patients with “good” outcomes had superior global alignment both pre- (SVA: −17 mm vs 108 mm, p 0.050). CONCLUSIONS The results of this study highlight intraoperative goals for three distinct sagittal morphotypes of severe CD: cervicothoracic, flat neck, and focal deformity. Distinct deformity specific intraoperative goals include obtaining proper sagittal global/cervical alignment for cervicothoracic patients, correcting maximal focal kyphosis in focal deformity patients, and correcting horizontal gaze for flat neck patients. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.