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Joint aspiration

Joint aspiration

Overview

Synovial fluid analysis is a series of tests performed on synovial (joint) fluid to help diagnose and treat joint-related abnormalities. To obtain a synovial fluid sample, a needle is inserted into the knee between the joint space. When the needle is in place the synovial fluid is then withdrawn. The sample is sent to the lab for analysis.

Review Date 4/24/2023

Updated by: C. Benjamin Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.