Validation and incorporation of digital entheses into a preliminary GLobal OMERACT Ultrasound DActylitis Score (GLOUDAS) in psoriatic arthritis.

OBJECTIVES: The main objective was to generate a GLobal OMERACT Ultrasound DActylitis Score (GLOUDAS) in psoriatic arthritis and to test its reliability. To this end, we assessed the validity, feasibility and applicability of ultrasound assessment of finger entheses to incorporate them into the scoring system. METHODS: The study consisted of a stepwise process. First, in cadaveric specimens, we identified enthesis sites of the fingers by ultrasound and gross anatomy, and then verified presence of entheseal tissue in histological samples. We then selected the entheses to be incorporated into a dactylitis scoring system through a Delphi consensus process among international experts. Next, we established and defined the ultrasound components of dactylitis and their scoring systems using Delphi methodology. Finally, we tested the interobserver and intraobserver reliability of the consensus- based scoring systemin patients with psoriatic dactylitis. RESULTS: 32 entheses were identified in cadaveric fingers. The presence of entheseal tissues was confirmed in all cadaveric samples. Of these, following the consensus process, 12 entheses were selected for inclusion in GLOUDAS. Ultrasound components of GLOUDAS agreed on through the Delphi process were synovitis, tenosynovitis, enthesitis, subcutaneous tissue inflammation and periextensor tendon inflammation. The scoring system for each component was also agreed on. Interobserver reliability was fair to good (κ 0.39-0.71) and intraobserver reliability good to excellent (κ 0.80-0.88) for dactylitis components. Interobserver and intraobserver agreement for the total B-mode and Doppler mode scores (sum of the scores of the individual abnormalities) were excellent (interobserver intraclass correlation coefficient (ICC) 0.98 for B-mode and 0.99 for Doppler mode; intraobserver ICC 0.98 for both modes). CONCLUSIONS: We have produced a consensus-driven ultrasound dactylitis scoring system that has shown acceptable interobserver reliability and excellent intraobserver reliability. Through anatomical knowledge, small entheses of the fingers were identified and histologically validated.

Systemic Vasculitis and Its Association with the Eye.

Vasculitis is a group of diseases characterized by the inflammation of the blood vessel walls. They are classified according to the size of the main vessel involved: large vessel, medium vessel, and small vessel vasculitis. Ophthalmic manifestations are quite common in most of these diseases. Episcleritis and scleritis are the most prevalent manifestation of vasculitis. However, there are certain ocular features characteristic of specific vasculitis entities. Given the severity and potential life-threat of these diseases, knowledge of the ocular manifestations is mandatory for the ophthalmologists.

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?

BACKGROUND: Digital subcutaneous tissue (SCT) changes are involved in dactylitis, a hallmark feature of psoriatic arthritis (PsA). There are no studies on the ultrasound (US) characteristics of the digital SCT in the general population. OBJECTIVES: To investigate the variability in US-measured thickness (TH) and color Doppler (CD)-detected blood flow of the SCT of the volar aspects of the fingers in a non-psoriatic population and to investigate the impact of the scanning method and demographics and clinical features on these measurements. METHODS: SCT TH and semiquantitative (SQD) and quantitative (QD) Doppler signals were measured in the bilateral second finger at the proximal and middle phalanges in 81 non-psoriatic volunteers [49 female, 32 men; 18-78 years]. Two scanning methods with and without (thick gel layer interposition) probe-skin contact were used. Demographics and clinical features were collected. RESULTS: There was high variability of SCT TH and Doppler measurements between individuals. All US measurements obtained without probe-skin contact were significantly greater than their corresponding measurements obtained with the probe contacting the skin (p < 0.001). SCT TH was positively related to dominant hand, age, masculine gender, weight, height, body mass index, and alcohol consumption while Doppler measurements were positively related to age and non-dominant hand. CONCLUSIONS: US-measured SCT thickness and Doppler-detected SCT blood flow of the volar aspect of the fingers seem to be highly variable in the non-psoriatic population as well as highly dependent on the US scanning method. This variability is of utmost importance for assessing dactylitis in PsA.

How much different is the semi-quantification of synovitis according to the ultrasound system and the blood flow detection technology?

AIM: To compare synovial blood flow scoring between different technologies and ultrasound (US) systems in active and inactive rheumatoid arthritis (RA). MATERIAL AND METHODS: Fifty-nine RA patients underwent B-mode, power Doppler (PD), colour Doppler (CD), B-Flow and High-Resolution (High-Res) PDI assessments of 6 joints with two US systems at two European centres. Each joint was semi-quantitatively scored for all ultrasound parameters. PD, CD and High-Res PDI synovial signal was also quantitatively scored. RESULTS: Correlations between the total score of SH with system 1 and 2 were very high (≥ 0.90, p<0.0001). Baseline correlations between systems for PD and CD total scores were moderate to very high (0.44-0.96, p<0.05). At baseline, there were no significant differences between ultrasound systems for PD or CD semiquantitative-based total scores in active or inactive patients (p>0,05). B-Flow and High-Res total scores were significantly lower than PD or CD total scores (p<0.05). CONCLUSION: A high-end and an entry-level US system were interchangeable for scoring SH and showed similar sensitivity and responsiveness in scoring synovial blood flow by PD and CD but not interchangeability. B-Flow and High-Res PDI were responsive, but they showed different sensitivity to detect synovial blood flow compared to conventional Doppler.

Examining the Forearm Intersection through Palpation and Ultrasonography.

BACKGROUND: Forearm intersection syndrome causes pain, swelling, and a rub at the dorsal distal forearm where the first extensor compartment muscles intersect with the second compartment tendons. Although primary care settings tend to treat mild cases, high-performance athletes may suffer from severe symptoms that require surgery. This proof-of-concept study aims to help detect the anatomical substrate of forearm intersection syndrome using palpation and ultrasonography when available. METHODS: Five individuals were studied using independent palpation and ultrasonography to identify the first dorsal compartment muscles and the second dorsal compartment tendons. The distances between the dorsal (Lister's) tubercle of the radius and the ulnar and radial edges of the first dorsal compartment muscles were measured to determine the location and extent of the muscle-tendon intersection. The palpatory and ultrasonographic measurements were compared using descriptive statistics and the paired t-test. RESULTS: The mean distances from the dorsal tubercle of the radius to the ulnar and radial borders of the first dorsal compartment muscles were 4.0 cm (SE 0.42) and 7.7 cm (SE 0.56), respectively, based on palpation. By ultrasonography, the corresponding distances were 3.5 cm (SD 1.05, SE 0.47) and 7.0 cm (SD 1.41, SE 0.63). Both methods showed a similar overlap length. However, ultrasonography revealed a shorter distance between the dorsal tubercle of the radius and the ulnar border of the first compartment than palpation (p = 0.0249). CONCLUSIONS: Our findings indicate that a basic knowledge of anatomy should help health professionals diagnose forearm intersection syndrome through palpation and, if available, ultrasonography.

What happens under the flexor tendons of the fingers in dactylitis?

AIM: Tenosynovitis is one of the most frequently described inflammatory lesions in psoriatic dactylitis. The aim of the study was to assess by ultrasound the distribution of content within the synovial sheath of the finger flexor tendons in a cadaveric experimental model of tenosynovitis and to describe anatomically the elements of the space between the flexor tendons and the palmar aspect of the proximal phalanx of the fingers. MATERIAL AND METHOD: Silicone was injected under ultrasound guidance into the digital flexor sheath of the index finger of a hand specimen. Ultrasound images of the distribution of the filling of the flexor synovial space with the injected material were obtained. These images were compared with images from patients with psoriatic dactylitis. The palmar regions of the hand and fingers were dissected to check the distribution of the injected silicone in the synovial cavity. Additionally, we dissected the 2nd to 5th fingers of five cadaveric hands, including the one used for the experiment. RESULTS: During the injection of the substance, we observed an increasing homogeneous hypoechoic band around the flexor tendons that differed from the images of patients. Dissection of the specimen showed the injected silicone distributed throughout the digital flexor sheath to the distal interphalangeal joint. In addition, we provided an illustrated anatomical description of the elements located between the flexor tendons and the palmar aspect of the proximal phalanx, the inflammation of which could simulate flexor tenosynovitis. CONCLUSION: The observations of this study may contribute to a better understanding of the anatomical structures involved in PsA dactylitis.

Palpation and Ultrasonography Reveal an Ignored Function of the Inferior Belly of Omohyoid: A Case Series and a Proof-of-Concept Study.

BACKGROUND: Palpation, a traditional haptic ability, is used daily by practitioners of all medical and surgical specialties to assess patients. In the current study, one of the authors, in a routine clinical setting, was able to deduce the dynamic features of the putative inferior belly of omohyoid. This led to a proof-of-concept study that yielded results consistent with the clinical findings. METHODS: The first part of the study involved a survey of 300 rheumatic disease patients in whom the greater supraclavicular fossa was explored by palpation. While the patient kept the head straight, the clinician placed his middle three fingers 2.5-3 cm dorsal to the clavicle in the window between the sternocleidomastoid and trapezius clavicular insertions, explored the supraclavicular fossa, and palpated the paired contractile inferior belly of the assumed omohyoid during flexion in the three orthogonal planes. In the second part of the study, five normal subjects were examined in a similar manner by the same clinician and had independent ultrasonography performed on the dominant side. Descriptive statistics were used, and Yates' corrected chi-squared test was applied to certain nominal variables. Additionally, a comparative anterolateral bilateral neck dissection was performed in a cadaveric specimen. RESULTS: Both studies showed that the contractile structure was the inferior belly of omohyoid and that its contraction occurred during anterior neck flexion and was opposite to the side of neck rotation, resembling the sternocleidomastoid. CONCLUSIONS: Palpation uncovered a previously unknown function of the inferior belly of omohyoid, suggesting that physical examination of the musculoskeletal system based on palpation may lead to hypotheses worthy of exploration.