diagnostic procedure by site synovial fluid analysis 2025-06-08T07:08:36Z PMID:30725799 The investigation of synovial fluid, the collection of fluid confined within a joint space. Synovial fluid is physiologic, and acts as a joint space lubricant of articular cartilage, and nutrient source through diffusion for surrounding structures including cartilage, meniscus, labrum, etc. Arthrocentesis is the process by which synovial fluid collection occurs by penetrating the joint space through aspiration.