Does Intra-Articular Injection of Platelet-Rich Plasma Have an Effect on Cartilage Thickness in Patients with Primary Knee Osteoarthritis?

OBJECTIVES: To determine the effect of intra-articular injection of platelet-rich plasma (PRP) in patients with primary knee osteoarthritis (OA) by clinical evaluation and ultrasonographic (US) assessment of cartilage thickness. PATIENTS AND METHODS: A total of 100 patients with mild to severe primary knee OA using the Kellgren- Lawrence (K-L) grading scale were included and divided into two groups. Group I included 50 patients who were given two intra-articular knee injections of PRP, 1 week apart; Group II included 50 patients who received non-steroidal anti-inflammatory drugs (NSAIDs) and chondroprotective drugs. Functional assessment of all OA patients was done using the basal WOMAC score, at 2 and 6 months. US assessment of femoral condylar cartilage thickness was conducted basally and at 6 months. RESULTS: Improvement of WOMAC score was observed at 2 and 6 months in Group I following PRP injection compared to Group II (p values < 0.001), The improvement of WOMAC in Group I occurred in all severity degrees of OA (p < 0.001). Moreover, a significant increase in cartilage thickness was found at the intercondylar area (ICA) at 6 months relative to baseline assessment by US in Group I (p = 0.041). CONCLUSION: Treatment with PRP injections can reduce pain and improve knee function in patients with various degrees of articular degeneration. Further studies are needed to clarify the anabolic effect of PRP on the articular cartilage.

Tc-99m sestamibi lower extremity muscle scan, is it a useful screening tool for assessment of preclinical atherosclerosis in rheumatoid arthritis patients?

Increased cardiovascular morbidity and mortality in rheumatoid arthritis (RA) patients cannot be entirely explained by traditional risk factors, suggesting that systemic inflammation characterizing this disease may accelerate atherosclerosis. Technetium 99m-Methoxyisobutyl isonitrile (Tc-99m sestamibi) is a myocardial perfusion imaging agent that has been suggested for evaluation of peripheral vascular disease. We used Tc-99m sestamibi muscle scan to investigate the prevalence of preclinical atherosclerosis in RA patients by perfusion reserve (PR) measurement. This study included 25 RA patients and 25 controls; 13/25 RA (GII) were on glucocorticoids and 12/25 (GI) were not. Database included full history, clinical examination, relevant laboratory tests, and Tc-99m sestamibi muscle scan for lower limbs. The percentage increase in the total counts (Cts) in the exercising calf termed PR was calculated according to the formula: (PR %) = (Cts in exercising calf-Cts in resting calf) ÷ (Cts in resting calf) × 100%. A significant difference was found between the means of PR in RA and controls (30.7±22.6% vs. 48.3±27.2%, P = 0.015). The mean perfusion reserve of GII correlated significantly with the steroids cumulative dose (P = 0.01). A statistically significant negative correlation was elicited between PR and disease duration (P = 0.024), while the negative correlation between PR and Disease Activity Index (DAS28) was not statistically significant (P = 0.065). Tc-99m sestamibi lower-limb muscle scan could be a useful screening tool for detection of preclinical atherosclerosis in lower limbs of RA patients, so early prophylactic measures and therapy modifications could be considered.