The Effect of Metal Instrumentation on Patient and Surgical Team Scatter Radiation Exposure Using Mini C-Arm in a Simulated Forearm Fracture Fixation Model

J Am Acad Orthop Surg Glob Res Rev. 2019 Jun 5;3(6):e089. doi: 10.5435/JAAOSGlobal-D-18-00089. eCollection 2019 Jun.


Introduction: To our knowledge, no studies have studied the effect of metal instrumentation (MI) in the field of fluoroscopy regarding changes in the intensity, direction of scatter, and degree of radiation exposure to the patient and surgical team. The goal of this study was to determine whether the presence of MI increases scatter radiation exposure to the patient and surgical team when using a mini C-arm in the horizontal and vertical positions.

Methods: Four trials were conducted using a lamb limb specimen and a mini C-arm to simulate a forearm/wrist fracture fixation scenario. Radiation scatter percentages were measured with the mini C-arm in a vertical and horizontal position with and without the presence of MI (a six-hole 3.5-mm limited-contact dynamic compression plate attached to the specimen with six cortical screws and a self-retaining retractor) using a parallel plate radiation detector.

Results: The patient, scrub technician, circulating nurse, and anesthesiologist were exposed to no detectable radiation. In the horizontal position with the presence of MI, there was a 181-fold increase in scatter radiation exposure to the first assistant's eyes (0.016% versus 2.893%, 1.4 × 10-6 Sv/min versus 3.5 × 10-5 Sv/min) and increased exposure to the surgeon's hands compared with the horizontal position with no MI. In the vertical position, the scatter radiation received by the first assistant's eyes increased (zero versus 2.9 × 10-6 Sv/min) with MI present, whereas the only radiation measured for the surgeon was in the right hand which did not change with MI present (2.2 × 10-5 Sv/min).

Discussion: MI in the field of fluoroscopy increases scatter radiation exposure to a degree that may place the first assistant's yearly eye exposure in excess of the International Commission on Radiological Protection limit. Surgeons and their assistants should wear lead aprons, thyroid shields, and leaded glasses and minimize the usage of fluoroscopy with MI in the field.