Schroeder Arthritis Institute, University Health Network Toronto, ON, Canada
Laura Passalent1, Sareh Keshavarzi1, Robert Inman1 and Nigil Haroon2, 1University Health Network, Toronto, ON, Canada, 2Schroeder Arthritis Institute, University Health Network; University of Toronto, Toronto, ON, Canada
Background/Purpose: A shift to virtual clinical encounters was required because of the COVID-19 pandemic. To date, there have been few studies exploring the utility of virtual examination of spinal mobility for patients with axial spondyloarthritis (axSpA) with varying reports of validity and reliability. The purpose of this study was to evaluate the validity of observed spinal mobility measures over live video in the assessment of patients with established axSpA.
Methods: Adult patients diagnosed with axSpA based on ASAS criteria, attending an urban academic Spondylitis Program and registered in the program's longitudinal research cohort were scheduled for a virtual video follow-up visit. Patients conducted spinal mobility maneuvers based on standardized verbal direction by the attending clinician. Spinal measures were visually estimated by the clinician observer and included tragus to wall distance, cervical spinal rotation, lumbar lateral flexion and intermalleolar distance. The modified Schober's maneuver to assess degree of lumbar flexion was converted to categorical variables based on normative values and was compared to estimated impairment of observed finger to floor distance (FFD) (i.e. normal, mild, moderate and severe impairment). Spinal measures were compared to patients' last in-person visit within a 24-month period. Concurrent validity of the virtual spinal measures was estimated based on correlation (Pearson's correlation coefficient) to previous in-person Bath Ankylosing Spondylitis Metrology Index (BASMI) scores (10-step analysis) and its individual components. Differences in lumbar flexion measures (modified Schober's and FFD) were evaluated using Chi Square test. Construct validity was assessed against the previous Bath Ankylosing Spondylitis Functional Index (BASFI), reflecting constructs of mobility and function.
Results: A total of 37 patients underwent virtual examination of spinal mobility. Approximately half were female (51.3%); mean age of 28.4 years (± 11.9); mean disease duration 13.6 years (±10.5); mean Bath Ankylosing Spondylitis Disease Activity Index was 4.1 (±2.5); 29.7% were receiving biologic treatment; 51.3% were receiving non-steroidal anti-inflammatories. Five clinical observers assessed participants (3 rheumatology fellows; 1 advance practice physiotherapist and 1 rheumatology resident). Average time between last in-person measure and virtual measure was 21.5 months (±6.5). Virtual BASMI scores were highly correlated with previous in-person BASMI score (r=0.75). Virtual component BASMI measures ranged from r=0.57 (lumbar lateral flexion) to r=0.79 (cervical rotation) compared to in-person measures. Estimation of lumbar flexion impairment of virtually observed FFD was not statistically different from in-person modified Schober's maneuver (p=0.46). Virtual BASMI scores were moderately correlated with the BASFI (r=0.61).
Conclusion: The results of this study suggest spinal mobility measures conducted over live video and conducted by an experienced clinician in rheumatology assessment are a valid substitution for in-person measurement.
Disclosures: L. Passalent, UCB, Novartis, AbbVie/Abbott; S. Keshavarzi, None; R. Inman, Novartis, Janssen, AbbVie/Abbott, Eli Lilly, Aria Pharmaceuticals, Amgen, Pfizer, Sandoz; N. Haroon, AbbVie/Abbott, Janssen, Eli Lilly, Novartis, UCB.
