What is your treatment approach for a young female who has an idiopathic small right elbow effusion with synovial thickening that has resulted in limitation in her range of motion?

I might aspirate the joint, send for gram staining, cell count, culture, and crystals, check serology to rule out autoimmune like RA or lupus, tick-born disease, and X-ray the joint. If all is negative, consider a short course of steroids, even synovectomy.