Symptomatic psoriatic dactylitis is associated with ultrasound determined extra-synovial inflammatory features and shorter disease duration

Abstract

Objectives To explore the link between ultrasonographic features of dactylitis in psoriatic arthritis (PsA) and symptoms, digital tenderness and duration of dactylitis. Methods Forty-eight cases of PsA dactylitis were investigated using high frequency ultrasound (US) both in grey scale (GS) and Power Doppler (PD), evaluating the presence and the degree of flexor tenosynovitis, peri-tendinous oedema, subcutaneous PD, extensor tendon involvement, GS synovitis and intra-articular PD signal (PDS) of the involved digits. Patients were compared according to the presence of local pain and digital tenderness, the duration of dactylitis and the concomitant treatment. ResultsThe presence of pain/tenderness was positively associated with US GS flexor tenosynovitis of grade > 2 (p < 0.001), PDflexor tenosynovitis (p < 0.001), peri-tendinous oedema (p < 0.001) and subcutaneous PDS (p < 0.001); moreover, it was negatively associated with GS synovitis (p < 0.001) and intra-articular PD (p < 0.001). The same positive and negative association with US findings were found comparing patients with duration of dactylitis shorter or longer than the median (24 weeks) (p < 0.001 for all comparisons). Conclusions Pain and digital tenderness are linked to dactylitis duration and earlier lesions are associated with extra synovial inflammatory changes. These findings suggest a hitherto unappreciated extra synovial basis for symptoms in PsA dactylitis.

Musculoskeletal Ultrasound in Monitoring Clinical Response to Treatment in Acute Symptomatic Psoriatic Dactylitis: Results from a Multicentre Prospective Observational Study

“…The link between sonographic features of dactylitis in PsA and local symptoms were evaluated for the first time in a recent study where local pain and tenderness were positively associated with GS FT (grade ≥ 2), PD FT, GS STO, and PD STO ( p < 0.001 for all comparisons) [ 18 ]. Moreover, there was a negative association with joint synovitis ( p < 0.001, both in GS and PD).…”

“…Adequate intra- and inter-rater reliability were assumed based on significant agreement reported in previous studies [ 18 , 19 , 20 , 21 , 29 ].…”

“…Compared to rheumatoid arthritis (RA), psoriasis, and healthy controls, PsA fingers demonstrate a high prevalence of US-determined periarticular soft tissue alterations, particularly at flexor tendon pulleys [ 15 , 16 , 17 ]. Recent studies reported significant extracapsular inflammation (FT and STO) in early dactylitis and a higher prevalence of joint synovitis at the proximal interphalangeal (PIP) level in chronic cases [ 18 , 19 , 20 , 21 ]. Additional cross-sectional studies linked specific US lesions (particularly FT and STO) with local, patient symptoms [ 18 , 19 , 20 , 21 ].…”

“…Recent studies reported significant extracapsular inflammation (FT and STO) in early dactylitis and a higher prevalence of joint synovitis at the proximal interphalangeal (PIP) level in chronic cases [ 18 , 19 , 20 , 21 ]. Additional cross-sectional studies linked specific US lesions (particularly FT and STO) with local, patient symptoms [ 18 , 19 , 20 , 21 ]. Moreover, a recent study showed that high values of LDI-b (indicating more disease) are associated with FT and STO on US [ 21 ].…”

How Variable Is the Volar Subcutaneous Tissue of the Digits on B-Mode and Color Doppler Ultrasound in Non-Psoriatic Individuals and Could It Be Included in a Dactylitis Score?

“…On imaging, particularly on ultrasound (US) and magnetic resonance imaging (MRI), dactylitis consists of a variable combination of inflammatory synovial and extra-synovial digital lesions such as enthesitis of tendons, ligaments, and pulleys, flexor tenosynovitis, peritendinous tissue inflammation, intra-articular synovitis along with osteitis (on MRI) and intra-or periarticular bony cortex proliferative changes at different locations in the fingers or toes [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Among these abnormalities, the presence of inflammatory changes in the subcutaneous tissue (SCT) of the volar aspect of the fingers, i. e., edema and increased thickness (TH) on B-mode (BM) with increased Doppler signal [17], has been shown not only as highly characteristic of PsA but also as distinguishing features between PsA and rheumatoid arthritis [15,20] and between symptomatic and asymptomatic PsA dactylitis [21,22].…”