SENSITIVITY AND SPECIFICITY OF THE AUTOMATED SQUEEZE TEST (GAENSLEN’S MANEUVER) FOR IDENTIFYING METACARPOPHALANGEAL SYNOVITIS BY MAGNETIC RESONANCE IMAGING

AB1128 Table 1. Baseline characteristics TOTAL CSA n=22 ERA n=22 LRA n=16 Age mean (SD) 44.7 (13.7) 37.6 (10.9) 49.05 (11.9) 47.5 (16.2) Female n (%) 50 (83.3) 18 (81.8) 18 (81.8) 14 (87.5) TJC median (IQR) 4 (12) 0.5 (4) 5 (13) 10 (11) SJC median (IQR) 3 (8) 0 (3) 5 (12) 7.5 (9) DAS28-ESR median (IQR) 4.8 (1.5) 5.4 (1.4) HAQ median (IQR) 0.64 (0.75) 1.47 (0.94) CDAI median (IQR) 18.07(16.8) 23.8 (15.5) Married n (%) 41 (68.3) 12 (54.5) 15 (71.4) 14 (93.3) Smoker n (%) 19 (31.7) 2 (22.7) 10 (45.5) 4 (25) Morning stiffness n (%) 31 (51.7) 4 (18.2) 16 (72.7) 11 (68.8) RF IgM positivity n (%) 46 (76.7) 9 (40.9) 12 (70.6) 4 (25) ACPA positivity n (%) 25 (41.7) 19 (86.4) 20 (90.9) 7 (43.8) Clinically suspect arthralgia, CSA; Early Rheumatoid Arthritis, ERA; Late Rheumatoid Arthritis, LRA; Tender Joint Count, TJC; Swollen Joint Count, SJC; Disease Activity Score – Erythrocyte Sedimentation Rate, DAS28-ESR; Health Activity Questionnaire, HAQ; Clinical Disease Activity Index, CDAI; Rheumatoid Factor, RF; Anti-citrullinated peptides antibodies,

Background: The term sarcopenia defines the muscle strenght loss and muscle mass loss due to aging, and it is one out of three criteria for the diagnose of frailty in the elderly. A number of studies have related the handgrip strength with muscle thickness (MT) in the forearm measured by ultrasound (US) 1 , but a standardized scanning protocol has not been described and its interobserver reliability has not been investigated yet.
Objectives: The aims of this study were to provide detailed description of the scanning protocol to measure the MT in the forearm and to test its feasibility and interobserver reliability.
Methods: A total of 27 consecutive subjects were enrolled at Ospedale "Carlo Urbani", in Jesi (Ancona, Italy): 2 healthy volunteers recruited from among our staff, and 25 patients referred to the Rheumatology Department affected by rheumatoid arthritis (5), psoriatic arthritis (4), spondyloarthritis (3), polymyalgia rheumatica (2), systemic lupus erythematosus (1), systemic sclerosis (1), overlap SLE/SSc (1), Sjögren syndrome (1), antisynthetase syndrome (1), undifferentiated connective tissue disease (1), osteoporosis (1), small vessels vasculitides (2) and fibromyalgia (2). The female to male ratio was 19/27, the mean age was 52.1 years (SD ±13.7), and the mean Body Mass Index was 27.4 Kg/m² (SD ±4.2). Four rheumatologists (SC, EC, GS, EF) trained in musculoeskeletal US, with a different degree of experience, performed the examinations using a MyLab ClassC (Esaote SpA) equipped with a broadband linear probe (frequency range 4-13 MHz). All subjects sat in front of the sonographer with their hands supinated and the forearm resting on the examining table. First, the coronoid process was imaged according to the "longitudinal scan of the coronoid recess" as indicated by the 2017 EULAR US guidelines. Then the probe was moved distally following bony cortex until the ulnar tuberosity was identified. Immediately distally to the ulnar tuberosity the bone turns flat and hyperechoic and this was taken as the anatomical reference for the measurement. Afterwards the probe orientation was changed to obtain a transverse view. During the rotation, the proximal third of the diaphysis of the radius was imaged. Two MT were measured, the ulnar MT (UMT) and the radial MT (RMT), between the subcutaneous tissue-muscle interface and the muscle-bone interface of each bone respectively. Background: Only few studies investigated the role of ultrasound (US) in the assessment of hyaline cartilage in rheumatoid arthritis (RA).
Recently, a positive correlation was found between the US measurement of the metacarpal head cartilage thickness (MCT) and both the anatomical MCT and the radiographic joint space width 1 .
Objectives: To evaluate inter-and intra-observer reliability in the assessment of MCT in RA patients and healthy subjects; to compare the agreement of the sonographers in the assessment of the MCT using different methods (i.e. semiquantitative and quantitative); to determine the interobserver smallest detectable difference (SDD) of MCT measured by US. Methods: US assessment was performed by two rheumatologists on 160 metacarpophalangeal (MCP) joints of 10 healthy subjects and 10 patients with RA (according to 2010 ACR/EULAR classification criteria) using a MyLab Twice (Esaote Biomedica, Genoa, Italy) equipped with a linear very high frequency probe (i.e. 10-22 MHz) To assess inter-observer reliability, the hyaline cartilage of metacarpal head from II to V digits of both hands were examined independently on the same day by two rheumatologists (an experienced musculoskeletal sonographer and an investigator with limited US training).
To assess intra-observer reliability, all the subjects were re-scanned using the same scanning protocol and the same US setting by one sonographer after a week. Hands were scanned with the MCP joints in maximal flexion (approximately 90°). The hyaline cartilage of all the metacarpal heads was scanned in longitudinal and transverse views in the central portion of the metacarpal head. Particular attention was paid on maintaining the probe in a position providing an angle of 90°between the direction of the US beam and the cartilage surface 2 .
MCT was scored both semi-quantitatively (using a five-grade scoring system 3 ) and quantitatively (using the average value of the longitudinal and transverse measures). The inter-and intra-observer agreements for assessing the MCT with the semiquantitative scoring system were calculated using Cohen's kappa and interpreted according to Landis and Koch. The inter-and intra-observer agreements for assessing the MCT with the quantitative scoring system were calculated using intraclass correlation coefficients (ICC) and their 95% confident intervals (95%CI A significant association was found between the CT value and age (r=-0.528, p<0.001), disease duration (r=-0.376, p=0.005) and grade of the semiquantitative scoring system (r=-0.80, p<0.001). No association was found between CT and BMI, weight, ACPA positivity and RF positivity.
Conclusion: This study demonstrated that a significantly higher prevalence of cartilage damage was found in RA patients using both the semiquantitative score and the quantitative assessment. In particular, in RA patients the hyaline cartilage of II and III MH is thinner in comparison with H. Finally, a significant association was found between the CT values and disease duration and age.