Exploring longitudinal associations of histologically assessed inflammation with symptoms and radiographic damage in knee osteoarthritis: combined results of three prospective cohort studies.

OBJECTIVE: To explore the associations between different histologically assessed, inflammatory synovial characteristics and subsequent clinical and structural aspects in knee osteoarthritis (OA). DESIGN: Knee OA patients, ranging in stage from early to advanced, were recruited from three different ongoing studies. Synovial tissue biopsies were taken and histologically assessed for six features (four inflammatory related aspects, fibrosis and fibrin deposition). Clinical aspects (WOMAC pain, functioning and stiffness and SF-36 vitality) and structural aspects (Kellgren and Lawrence (KL)-grade, joint space narrowing (JSN; 0-3) and osteophytes (0-3), and reception of total knee replacement (TKR)) were repeatedly assessed during follow-up. Associations between histology and clinical and structural aspects were analysed using linear mixed model analyses and cox proportional hazards analysis. RESULTS: Biopsies of 83 patients (median complaint duration: 5 [2-8] years) were analysed. Follow-up was a median of 1.4 [0.8-2.7] years for clinical and 1.8 [0.2-5.2] years for structural aspects. Fibrosis and fibrin deposition were inversely correlated with the inflammatory features. A higher fibrosis score was associated with a lower scores for KL-grade, JSN and osteophytes, while higher scores for perivascular oedema, synovial lining thickness and vascularisation were associated with higher scores for structural aspects during follow-up. No associations were found between each of the histological features and any of the clinical aspects or the chance for TKR during follow-up. CONCLUSIONS: Inflammatory related histological aspects are associated with subsequent increased radiological severity in knee OA, while fibrosis seems to protect against this, providing a potential therapeutic target for OA treatment.

Lack of beneficial effects of low-dose radiation therapy on hand osteoarthritis symptoms and inflammation: a randomised, blinded, sham-controlled trial.

OBJECTIVES: Low-dose radiation therapy (LDRT) is widely used as treatment for osteoarthritis (OA) in some countries, while relatively unknown in others. Systematic literature review displayed a lack of high-level evidence for beneficial effects in clinical practice. The aim was to assess the efficacy of LDRT on symptoms and inflammation in hand OA patients in a randomised, blinded, sham-controlled trial, using validated outcome measures. DESIGN: Hand OA patients, ≥50 years, with pain ≥5 (scale 0-10) and non-responding to conservative therapy were included and randomised 1:1 to receive LDRT (6 × 1 Gy in 2 weeks) or sham (6 × 0 Gy in 2 weeks). Primary outcome was the proportion of OMERACT-OARSI responders, 3 months post-intervention. Secondary outcomes were pain and functioning (Australian/Canadian Hand Osteoarthritis Index; AUSCAN), quality of life (Short Form Health Survey; SF36) and inflammatory outcomes: erythrocyte sedimentation rate and C-reactive protein serum levels, effusion, synovial thickening and power Doppler signal on ultrasound (range 0-3). RESULTS: Fifty-six patients were included. After 3 months, no significant difference in responders was observed between groups (LDRT: 8 (29%); sham: 10 (36%); difference -7% (95%CI -31-17%)). Also, differences in clinical and inflammatory outcomes between groups were small and not significant. CONCLUSIONS: We were unable to demonstrate a substantial beneficial effect of LDRT on symptoms and inflammation in patients with hand OA, compared to sham treatment. Although a small effect can not be excluded, a treatment effect exceeding 20% is very unlikely, given the confidence interval. Therefore, in the absence of other high-level evidence, we advise against the use LDRT as treatment for patients with hand OA. CLINICAL TRIAL REGISTRATION NUMBER: NTR4574 (Dutch Trial Register).

The efficacy and safety of low-dose radiotherapy on pain and functioning in patients with osteoarthritis: a systematic review.

Low-dose radiotherapy (LD-RT) has been widely used for treatment of non-malignant disorders since its introduction and animal studies show anti-inflammatory effects in osteoarthritis (OA). However, the evidence for its effect in clinical practice remains unclear. Therefore, the aim of this study is to systematically summarise the literature on effectiveness of LD-RT on pain and functioning in patients with OA and its safety. Broad search terms were used to search PubMed, EMBASE and Web of Science. Primary inclusion criteria were osteoarthritis as indication, radiotherapy as intervention, written in English, German or Dutch and published since 1980. Study quality was assessed using the EPHPP Quality Assessment Tool for Quantitative Studies (scale: strong, moderate, weak). Seven studies were suitable for inclusion, all with retrospective uncontrolled observational design. Methodological quality of all studies was judged as weak. Most studies used 2-3 RT sessions per week for 2 weeks, some with booster session after 6 weeks. Generally, non-validated single-item measurement instruments were used to evaluate the effect of LD-RT on pain and function. Across the studies, in 25-90 and 29-71 % of the patients pain and functioning improved, respectively. Side effects were described in one study, none were reported. Our results show that there is insufficient evidence for efficacy or to confirm the safety of LD-RT in treatment of OA, due to absence of high-quality studies. Therefore, a well-designed, sham-controlled and blinded randomised trial, using validated outcome measures is warranted to demonstrate the value of LD-RT for OA in clinical practice.