Background/Purpose: Systemic sclerosis is a multisystem disease characterized by the development of microangiopathy and subsequent fibrosis of skin and internal organs. The joint involvement is common, but its prevalence and characteristics differ in the literature. Traditionally, it has been assessed by clinical examination, which may underestimate the presence of synovitis and erosions. Objective: To evaluate the characteristics of joint involvement in a cohort of patients with systemic sclerosis assessed by clinimetric and ultrasonographic (US) measures.

Methods:  Observational cross-sectional study. Consecutive patients with systemic sclerosis according to ACR-EULAR 2010 criteria were included. Acute phase reactants (erythrocyte sedimentation rate and C-reactive protein), immunology laboratory, rheumatoid factor and antiCCP were measured the day of clinical examination. Disease activity was measured by DAS28, hands’ functionality was assessed by Duruöz Index and modified Kapandji Test, extension of cutaneous involvement by modified Rodnan Score and disability by HAQ-A. All US examinations were performed by an experienced rheumatologist, blinded to clinical and laboratory data. The US evaluation included examination in grayscale and power Doppler with a linear transducer (10-18MhZ) in the longitudinal and transverse sections of: radiocarpal and intracarpian joint, second to fifth metacarpophalangeal joint, tibiotalar joint, 1st to 6th wrist tendon extensor compartment, 1st to 5th digital flexor tendon, Achilles tendon, peroneal tendons, posterior tibialis tendon and tibialis anterior tendon, all bilaterally. For descriptive statistics, continuous variables were described as median (IQR) and categorical variables as percentages. To analyze the differences between the groups with and without ultrasound findings, Mann Whitney test was used for continuous variables, and Fisher exact test for categorical variables. It was considered as significant a p value < 0.05.

Results: 40 consecutive patients with systemic sclerosis were included. Median age was: 53 (IQR 45-59), 87.5% were women. The median time since the first not Raynaud manifestation was 4 years (IQR 2-6). The 72.5% of patients had limited scleroderma, Barnet subtype 1, 77.5% had Raynaud, 50% of patients reported suffering from arthralgia and only 4 patients arthritis, 35% (n = 14) had pitting and 17.5% (n = 7) active digital ulcers. Only 1 patient had a history of amputation and 2 had calcinosis. The median Duruöz index was 12.7 (SD 14.3), Kapandji Test 80 (SD 23), HAQ 0.79 (SD 0.83) and DAS28: 2.77 (IQR: 2.18- 3.34). The US findings were: 47.5% (n = 19) of patients presented at least one finding by ultrasound, 32.5% (n = 13) proliferative synovitis grade II in the radiocarpal joint and 2.5% (n = 1) Grade III. Only 2 patients had PD positive grade II. At the tibiotalar joint, only 2 patients had moderate synovitis. 15% (n = 6) had extensor compartment tenosynovitis and 30% (n = 12) digital flexor tenosynovitis. The 42, 5% of patients (n = 17) had tenosynovitis and/or tendinopathy in tibialis anterior tendon, posterior tibialis tendon, peroneal tendons and Achilles tendon. 12.5% (n = 5) had erosions in styloid process (n = 4) and 2nd metacarpophalangeal (n = 1). No statistically significant differences were found between the groups with and without ultrasound findings regarding the following variables: Median HAQ, DAS28, Score Rodnan, Duruöz Index and Kapandji Test, anti centromere and Scl-70 antibodies, RF, acute phase reactants, VAS, disease duration, age or treatments (p> 0.05).

Conclusion: The joint involvement in systemic sclerosis is frequent, evaluated both clinically and by ultrasound. This manifestation should be considered in daily care in patients with systemic sclerosis.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/clinical-and-ultrasonographic-evaluation-of-joint-involvement-in-patients-with-systemic-sclerosis/