Patients with an intraarticular elbow fracture and/or dislocation. Synovial fluid from the injured elbow will be obtained during the subject's emergency department encounter by one of the Chief Residents or Attending surgeon as part of standard of care procedures for pain control-related injection and aspiration. Patients with an intraarticular elbow fracture and/or dislocation receive an intraarticular elbow injection with anesthetic (i.e. lidocaine or marcaine) to provide analgesia for elbow range of motion testing and orthopaedic reduction maneveuers as the current standard of care. The patients would be asked to consent for 2 elbow joint aspirations: 1.Aspiration of the injured elbow at time of surgical fracture fixation; 2.Aspiration of the uninjured elbow at time of surgical fracture fixation.

Synovial fluid aspiration (act of using an 18 gauge needle to obtain synovial fluid from the elbow) in the emergency room for patients with the eligible elbow fracture (as defined in inclusion/exclusion criteria) is performed in conjunction with the anesthetic injection as part of standard of care. The elbow will be prepped as per usual for the anesthetic injection. An 18 gauge needle will be inserted through a lateral approach. The subject's elbow will be aspirated. The syringe with the aspirate would be removed from the needle while the needle would remain in the subject's elbow joint. The syringe with anesthetic would then be connected to the needle, and the anesthetic would be injected into the elbow joint. Therefore, no risks from a separate aspiration would be conferred to the patient.