Background There is no published work validating the techniques for examining joint and tendon pathology with musculoskeletal ultrasound (MSUS) in systemic sclerosis (SSc).
Objectives To examine MSUS of the joints and tendons of the wrists/hands in SSc through the OMERACT filter (face, construct and content validity; reliability and feasibility).
Methods Patients were ≥18 years old with SSc as defined by ACR criteria. Those with overlapping rheumatological diseases were excluded. Clinical assessment was performed on the same day as the US examination and included a 28 swollen/tender joint count, modified Rodnan skin thickness scoring (mRSS), measurement of contractures, scleroderma Health Assessment Questionnaire (SHAQ), physician/patient global assessment and pain visual analogue scale (VAS). Demographic, clinical data, and lab results were obtained from medical charts.
MSUS assessment: One investigator (AS-E) performed US examinations of 13 joints (Wrist, MCPs 2-5, PIPs 2-5, DIPs 2-5) in the dominant hand, both in the dorsal and volar aspects, using longitudinal and transverse planes. Gray scale (GS) and power Doppler (PD) 4-grade semiquantitative scales were used to evaluate joints (1). GS tendonitis was scored on a 0-1 scale and PD synovitis was scored on a 0-3 scale. US was performed with logiq E9; General electric scanner by means of 5-16 MHz linear array transducer. B-mode frequency was 15. PD settings were: pulse repetition frequency 800 Hz, frequency 10 and low wall filter. Intra-observer reliability was assessed by performing the evaluation twice during an up to 2 weeks interval in 5 patients. Convergent and discriminant clinical construct validity were evaluated by correlating swollen/tender joint count and SHAQ scores respectively to US measures. Content validity was evaluated by including a wide range of patients. Feasibility was evaluated by measuring the length of time required for the examination. Face validity was examined through a literature search.
Results Eighty-one consecutive SSc patients and 14 healthy controls participated. Feasibility: Mean Length of examination was 36 minutes (range: 18-66 min). Face validity: Expert opinion regarding face validity of the measure was examined through a literature search, which validated this measure as logical and appropriate (2). Content validity: 61 patients were females and 15 were males; Age range: 22 to 80yrs; disease duration range: 0.4-29yrs. 19 patients had contractures (≥45 degrees in at least 1 PIP). 23 had limited disease. 75.7% had lung involvement. Convergent construct validity: A trend toward statistical significance was seen between swollen joint count correlation with PD tendonitis (Rs=0.22, p=0.07). Discriminant construct validity: SHAQ correlated with US erosions (Rs=0.5, p=0.0003); Pain VAS correlated with PD tendonitis (Rs=0.21, p=0.05). Reliability: Intra-reader ICCs was 0.96-1.00.
Conclusions Evidence of face, content, and discriminant construct validity as well as reliability and feasibility were found for US examination of joint and tendon involvement of the wrists and hands in scleroderma.
Szkudlarek M et al. Arthritis Rheum 2003.
Elhai M et al. Arthritis Care & Research 2012.
Disclosure of Interest A. Scheiman-Elazary: None declared, V. Ranganath: None declared, A. Ben-Artzi: None declared, L. Duan: None declared, S. kafaja: None declared, N. Borazan: None declared, T. Woodworth: None declared, D. Elashoff: None declared, P. Clements: None declared, D. Furst Grant/research support: AbbVie, Actelion Pharmaceuticals US, Amgen, BMS, Gilead, GSK, NIH, Novartis Pharmaceutical Corporation, Pfizer Inc, Roche/Genentech, UCB, Janssen Pharmaceutica Product,