Ultrasonography in osteoarthritis: recent advances and prospects for the future

Intra-articular onabotulinumtoxinA in osteoarthritis knee pain: effect on human mechanistic pain biomarkers and clinical pain

OBJECTIVES

OnabotulinumtoxinA (onabotA) attenuates peripheral nociceptive transduction and consequently neuronal firing. The aim of this mechanistic study was to evaluate the effect of intra-articular (IA) onabotA in patients with painful knee osteoarthritis (OA).

METHOD

We conducted a double-blind, randomized, placebo-controlled, 12-week trial using a single ultrasound-guided IA injection of onabotA (200 U). Patients (N = 121) were randomized to receive onabotA (n = 61) or placebo (n = 60). Mechanistic pain biomarkers and clinical outcomes were used for profiling the effect. The biomarkers were pressure pain thresholds (PPTs) from the knee joint (localized sensitization) and extra-articular sites (widespread sensitization), and wind-up pain (central sensitization). Clinical assessments included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), average daily pain (ADP), patient global impression of change (GIC), and rescue medication. The painDETECT questionnaire (PD-Q) was used for subgrouping patients (nociceptive, neuropathic, and mixed/uncertain).

RESULTS

The nociceptive and non-nociceptive groups were identical with respect to all baseline data. No significant differences in clinical efficacy parameters were found between onabotA and placebo in the entire population. The nociceptive group showed significant improvement after IA onabotA at week 8 for all WOMAC outcomes, ADP at weeks 9 and 10, and patient GIC at week 12, and significant reduction in rescue medication counts within each 14-day period at weeks 9 and 10. After 4, 8, and 12 weeks, significant correlations were obtained in the onabotA group between ADP (both the entire group and the nociceptive group) and various sensitization parameters. The nociceptive group showed pronounced effects on widespread sensitization.

CONCLUSIONS

Intra-articular onabotA given to patients with nociceptive knee OA reduced pain sensitization together with improvement in pain and function.

Validity of musculoskeletal ultrasound for identification of humeroradial joint chondral lesions: a preliminary investigation

CONTEXT

Epicondylalgia is a common condition involving pain-generating structures such as tendon, neural, and chondral tissue. The current noninvasive reference standard for identifying chondral lesions is magnetic resonance imaging. Musculoskeletal ultrasound (MUS) may be an inexpensive and effective alternative.

OBJECTIVE

To determine the intrarater reliability and validity of MUS for identifying humeroradial joint (HRJ) chondral lesions.

DESIGN

Cross-sectional study.

SETTING

Clinical anatomy research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Twenty-eight embalmed cadavers (14 women, 14 men; mean age = 79.5 ± 8.5 years).

MAIN OUTCOME MEASURE(S)

An athletic trainer performed MUS evaluation of each anterior and distal-posterior capitellum and radial head to identify chondral lesions. The reference standard was identification of chondral lesions by gross macroscopic examination. Intrarater reliability for reproducing an image was calculated using the intraclass correlation coefficient (3,k) for measurements of the articular surface using 2 images. Intrarater reliability to evaluate a single image was calculated using the Cohen κ for agreement as to the presence of chondral lesions. Validity was calculated using the agreement of MUS images and gross macroscopic examination.

RESULTS

Intrarater reliability was 0.88 (95% confidence interval = 0.77, 0.94) for reproducing an image and 0.93 (95% confidence interval = 0.80, 1.06) for evaluating a single image. Identifying chondral lesions on all HRJ surfaces with MUS demonstrated sensitivity = 0.93, specificity = 0.28, positive predictive value = 0.58, negative predictive value = 0.77, positive likelihood ratio = 1.28, and negative likelihood ratio = 0.27.

CONCLUSIONS

Musculoskeletal ultrasound is a reliable and sensitive tool for a clinician with relatively little experience and training to rule out HRJ chondral lesions. These results may assist with clinical assessment and decision making in patients with lateral epicondylalgia to rule out HRJ chondral lesions.

Emerging role of ultrasonography in rheumatoid arthritis: optimizing diagnosis, measuring disease activity and identifying prognostic factors

Ultrasonography is a sensitive imaging modality that provides valuable information regarding early inflammatory changes that are not detected by clinical examination or X-rays, such as subclinical synovitis and erosions. This information may improve the management of rheumatoid arthritis by providing a more timely and accurate diagnosis, identifying poor prognostic factors, more accurately monitoring response to therapeutic intervention, improving treatment decisions and more accurately assessing remission. Ultrasonography could play a critical role in minimizing disease activity through strict monitoring and aggressive therapeutic adjustment, which has emerged as an approach to improve long-term outcomes for patients with rheumatoid arthritis.

Efficacy of ultrasound-guided steroid injections for pain management of midfoot joint degenerative disease

OBJECTIVE

To examine the efficacy of ultrasound (US)-guided injections for midfoot joint degenerative changes.

MATERIALS AND METHODS

The US images and radiographs of 63 patients with midfoot joint degenerative changes were retrospectively reviewed. In those patients who had US-guided intra-articular steroid injection, the response to the injection was recorded by reviewing the 2-week pain diaries and clinical notes. Partial or complete pain relief was defined as a positive response and the same or increased level of pain as a negative response to the injection.

RESULTS

Fifty-nine (59/63, 93.6%) patients with midfoot joint degenerative changes received US-guided injection. The majority of patients had a positive response up to 3 months post-injection (78.4% still experiencing pain relief at 2 weeks, 57.5% at 3 months and fewer than 15% of patients further than 3 months post-injection). The number of positive therapeutic responses did not differ significantly between patients with diagnostic and non-diagnostic response (p = 0.2636).

CONCLUSIONS

US-guided intra-articular injections for midfoot degenerative changes can have a good therapeutic result in the majority of patients up to 3 months post-injection. Therapeutic response cannot be predicted by a positive diagnostic response.

First assessment of three-dimensional quantitative photoacoustic tomography for in vivo detection of osteoarthritis in the finger joints

PURPOSE

The purpose of this pilot clinical study is to assess three-dimensional (3-D) quantitative photoacoustic tomography (qPAT) for in vivo detection of osteoarthritis (OA) in the finger joints.

METHODS

All subject data were handled in compliance with the rules and regulations concerning the privacy and security of protected health information under HIPAA. Seven female subjects (two OA patients and five healthy controls) entered the study and their distal interphalangeal (DIP) joints were examined by a 3-D photoacoustic scanner. 3-D optical absorption coefficient images of all the photoacoustically examined joints were recovered using a 3-D qPAT reconstruction algorithm.

RESULTS

The recovered quantitative photoacoustic images revealed obvious difference in the optical absorption coefficient of the joint cavity (cartilage and synovial fluid) between the OA and healthy joints. Quantitative analysis of the joints also indicated an apparent difference in the recovered joint spacing between the OA and healthy subjects.

CONCLUSION

This initial clinical evaluation suggests that it is feasible to detect osteoarthritis in the finger joints with our 3-D qPAT approach, which has paved the way to further statistically evaluate the diagnostic performance of the 3-D qPAT approach in comparison with radiography or magnetic resonance imaging (MRI) on a sample of hand osteoarthritis.

Targeting the synovial tissue for treating osteoarthritis (OA): where is the evidence?

Osteoarthritis (OA) is often a progressive and disabling disease, which occurs in the setting of a variety of risk factors--such as advancing age, obesity and trauma--that collude to incite a cascade of pathophysiological events within joint tissues. An important emerging theme in OA is a broadening of focus from a disease of cartilage to one of the 'whole joint.' The synovium, bone and cartilage are each involved in pathological processes that lead to progressive joint degeneration. Additional themes that have emerged over the past decade are novel mechanisms of cartilage degradation and repair, the relationship between biomechanics and biochemical pathways, the importance of inflammation and the role of genetics. In this article, we review the molecular, clinical and imaging evidence that synovitis is not an 'incidental finding of OA', but plays a significant role in disease pathogenesis, and could therefore represent a target for future treatments.

More intrinsic parameters should be used in assessing degeneration of articular cartilage with quantitative ultrasound

During the last decade, the quantitative ultrasound technique has been widely employed as a versatile modality to investigate a thin but crucial tissue layer – the articular cartilage. Previous studies provide information about the morphology and mechanical and acoustic properties of the tissue derived from ultrasound measurements and correlate them with cartilage degeneration. In a previous issue of Arthritis Research & Therapy, Kuroki and colleagues presented a study about the relationship between International Cartilage Repair Society grading and ultrasound echo magnitude, duration, and interval in human knee cartilage. We think indirect measurements of the intrinsic physical characteristics of cartilage, as reported in this study, should be interpreted more carefully as they can be affected by many experimental and physical factors. In this editorial, we offer our opinion that more intrinsic material parameters should be selected for the assessment of degeneration states of cartilage using quantitative ultrasound.