Construct validity of a clinically correlated knee osteoarthritis ultrasonographic scale: a cross-sectional observational study

Ultrasound-detected knee synovitis in patients with rheumatoid arthritis after total knee arthroplasty

OBJECTIVES

To evaluate the prevalence of ultrasound (US)-detected knee synovitis in patients with rheumatoid arthritis (RA) with a history of total knee arthroplasty (TKA) and to explore its association with RA disease activity and clinical outcomes.

METHODS

The present, retrospective, cross-sectional study retrieved the data from electronic medical records of patients with RA who were followed up for TKA and had musculoskeletal ultrasound assessment at the study centre from 1 January 2021 through 31 December 2021.

RESULTS

Forty-two patients with 67 post-TKA knee joints were enrolled in the present study. US-detected synovitis of the post-TKA knee was present in 15 knees (22.4%) and 12 patients (28.6%). There was no difference in disease activity scores or the pain domain of Knee Injury and Osteoarthritis Outcome Score between the patients with (n = 12) and without (n = 30) US-detected knee synovitis. The proportion of patients with the intensification of antirheumatic drugs after MSUS assessment was significantly higher in patients with US-detected synovitis compared to those without US-detected synovitis (41.7 versus 6.7%, P = .01).

CONCLUSIONS

US-detected synovitis of the knee was present at 22.4% of post-TKA knee joints. Patients with US-detected synovitis of post-TKA knees were likely to receive an intensification of antirheumatic drugs.

The ultrasound assessment of osteoarthritis: the current status

Traditionally, osteoarthritis (OA) is diagnosed with the clinical examination supplemented by the conventional radiography (CR). In the research literature, the role of ultrasound (US) imaging in the diagnostics of OA has risen steadily during the last two decades. US imaging is cheap and globally widely available often already in primary healthcare. Here, we reviewed the most essential US literature focusing on OA diagnostics and progression prediction using the various search engines. Starting from the year 2000, our search provided 1 445 journal articles. After reviewing the abstracts, 89 articles were finally included. Most of the reviewed articles focused on the imaging of knee and hand OA, whereas only a minority dealt with the imaging of hip, ankle, midfoot, acromioclavicular, and temporomandibular joints. Overall, during the last 20 years, the use of US imaging for OA assessment has increased in the scientific literature. In knee and hand joints, US imaging has been reported to be a promising tool to evaluate OA changes. Furthermore, the reproducibility of US as well as its association to MRI findings are excellent. Importantly, US seems to even outperform CR in certain aspects, such as detection of osteophytes, joint inflammation, meniscus protrusion, and localized cartilage damage (especially at the medial femoral condyle and sulcus area). Based on the reviewed literature, US can be truly considered as a complementary tool to CR in the clinical setup for OA diagnostics. New technical developments may even enhance the diagnostic value of the US in the future.

Clinical examination, ultrasound assessment and aspiration of knee effusion in primary knee osteoarthritis patients

BACKGROUND

To assess the diagnostic performance of clinical examination and ultrasound (US) assessment of knee effusion in primary knee osteoarthritis (KOA) patients. Furthermore, the success rate for effusion aspiration and the factors related to it were investigated.

METHODS

This cross-sectional study included patients diagnosed with primary KOA-induced knee effusion clinically or sonographically. The affected knee of each patient was subjected to clinical examination and US assessment using the ZAGAZIG effusion and synovitis ultrasonographic score. Patients with confirmed effusion and consented to aspiration were prepared for direct US-guided aspiration under complete aseptic techniques.

RESULTS

One hundred and nine knees were examined. During visual inspection, swelling was detected in 80.7% of knees and effusion was confirmed by US in 67.8% of knees. Visual inspection was the most sensitive at 90.54% while bulge sign was the most specific at 65.71%. Only 48 patients (61 knees) consented to aspiration procedure; 47.5% had grade III effusion, and 45.9% had grade III synovitis. Successful aspiration was achieved in 77% of knees. Two needle types were used; a 22 gauge / 3.5-inch spinal needle in 44 knees and an 18 gauge/ 1.5-inch needle in 17 knees, with a success rate of 90.9% and 41.2%, respectively. Aspirated amount of synovial fluid correlated positively with effusion grade (r_s=0.455, p < 0.001) and negatively with synovitis grade on US (r_s = - 0.329, p = 0.01).

CONCLUSIONS

The superiority of the US over clinical examination in detecting knee effusion suggests that US should be used routinely to confirm the presence of effusion. Long needles (spinal needle) may have a higher success rate of aspiration than shorter needles.

Role of global femoral cartilage in assessing severity of primary knee osteoarthritis

Background/objective

Osteoarthritis is a degenerative joint disease marked by structural changes in the joint. Radiological evaluation can be used to assess structural changes. Pain, inflammation, and stiffness are common clinical symptoms, leading to limitations in daily activities. Ultrasound, unlike traditional radiography, allows for a direct examination of changes in soft tissues. In addition, it is sensitive in detecting osteophytes as well as identifying early OA changes in femoral cartilage associated with clinical manifestations and function.

Results

A cross- sectional study of 40 patients with primary KOA diagnosed according to the American College of Rheumatology (ACR) criteria. After radiographic evaluation using Kellgren-Lawrence (K-L) scale and US examination assessing global femoral hyaline cartilage (GFC), osteophytes, meniscal extrusion, effusion, and Baker’s cyst of the most symptomatic knee, there was significant correlation between (K-L) grading and (GFC) ultrasonographic grading (p = < 0.001). After assessment of pain and functional disability using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale, there was significant correlation between KL and GFC grading with age (p = < 0.001 for both), disease duration (p = < 0.001 for both) as well as WOMAC total scores (p = < 0.001 for both). GFC grading was the only independent predictor relative to other ultrasonographic variables for WOMAC total score (p = < 0.001).

Conclusions

US is a valid tool to evaluate knee joint space and is well correlated with radiographic images. KOA severity assessed by KL grading and GFC ultrasonographic grading showed good correlation with age, duration of the disease, pain intensity, and functional disability.