Complex sentence: Synovial fluid cultures are positive in over 90% of nongonoccocal arthritis; however, it is possible for the culture to be negative if the patient received antibiotics prior to the joint aspiration.
Split into simpler sentences: Synovial fluid cultures are positive in over 90% of nongonoccocal arthritis. However, it is possible for the culture to be negative if the patient received antibiotics prior to the joint aspiration.