Introduction: While there are numerous studies on cervical sagittal alignment, few studies actually report HRQOL correlations. This study investigates correlations between established cervical outcomes and regional, focal and dynamic alignments.
Methods: In a retrospective review of prospectively collected cervical deformity (CD) patients, bi-variable correlations between HRQL scores and radiographic parameters were calculated using both the entire cohort and the driver of deformity (C=cervical, CT=cervico-thoracic). Radiographic parameters included cervical global alignment parameters (C2-C7 angle, cSVA, TS-CL, C0-C2 angle), focal parameters (number of kyphotic levels>5° (nK), maximum segmental kyphosis (maxK), number of listhesis>4mm (nL), maximum lysthesis (maxL)) and dynamic parameters (C2-7 range of motion (ROM), kinematic area (kArea), C0-C2 ROM).
Results: 62 patients were included (mean 61±7yo, 60%F, 32C and 29CT). Mean sagittal parameters for the cervical alignment were C2-C7 -5±30°, cSVA 47±34mm, TS-CL 35.9±26.7°, C0-C2 40±11.6°, nK 1.9±1, maxK -13.4±8.5°, nL 0.8 ±1.2, maxL 6±8mm. Mean HRQOL scores included NDI 48±18, mJOA 13.5±2.4, EQ5D 9.9±2.2 and VAS 61±24. There was no correlation between regional parameters and HRQOL, but mJOA correlated significantly with maxK (0.324, p=0.017) and kArea (0.321, p=0.023). The stratification by deformity driver revealed significant correlations between maxK and mJOA in the C patients, and between nK and mJOA in CT patients. In addition, radiographic parameters correlated with individual mJOA, EQ5D and NDI questions (Table).
Conclusions: In cervical deformity patients, focal and dynamic parameters correlated more with mJOA than did regional cervical alignment. This suggests that focal and dynamic parameters play a larger role in the quality of life of these patients than regional cervical alignment. The NDI total score did not correlate with any cervical parameters.These findings call into question the utility of the NDI when evaluating patients with cervical deformity.
Patient Care: This research will improve patient care by providing evidence that surgeons should evaluate focal, dynamic and regional cervical alignment differently as well as reevaluate the HRQOL measures used to determine quality of life of CD patients.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) understand that focal and dynamic parameters, may be a better indictor of quality of life than regional cervical alignment, 2) understand that NDI does not correlate with any cervical parameters, and 3) recognize that the NDI may need to be reevaluated for it's use in treatment of cervical deformity.