Establishing local diagnostic reference levels for common orthopaedic procedures using the mini C-arm fluoroscope

Area of Science:

• Medical Physics
• Orthopaedic Surgery
• Radiology

Background:

• Mini C-arm fluoroscopes are essential for intraoperative guidance in orthopaedics, placing radiation safety responsibility on surgeons.
• The UK Ionising Radiation (Medical Exposure) Regulations mandate radiation dose limitation and performance auditing.
• Absence of national diagnostic reference levels (DRLs) for mini C-arms necessitates local guideline establishment.

Purpose of the Study:

• To establish local diagnostic reference levels (DRLs) for mini C-arm fluoroscopy.
• To provide radiation safety guidelines for orthopaedic surgeons in the UK.
• To audit and benchmark radiation exposure from mini C-arm procedures.

Main Methods:

• A retrospective audit of end dose-area product (DAP) was conducted for 1664 trauma and orthopaedic procedures.
• Local DRLs were formulated using the third quartile DAP values, aligning with conventional fluoroscope methodology.
• Data were collected over seven years at a district general hospital.

Main Results:

• The third quartile DAP values varied by anatomical site, with forearm (5.38 cGycm²), hand (7.62 cGycm²), and foot/ankle (8.56 cGycm²) procedures showing the lowest doses.
• Wrist (10.64 cGycm²) and elbow (14.61 cGycm²) procedures exhibited the highest third quartile DAP values.
• This audit represents the largest dataset to date for establishing mini C-arm DRLs.

Conclusions:

• This study provides the largest dataset for establishing local DRLs for mini C-arm use.
• The established local DRLs serve as valuable guidelines for other centres developing their own safety protocols.
• These findings support safe and best practice in radiation management for orthopaedic surgeons.