Optimization of the fixed-flexion knee radiograph.

Osteoarthritis and Cartilage (Impact Factor: 4.66). 12/2007; 15(11):1221-4. DOI: 10.1016/j.joca.2007.05.012
Source: PubMed

ABSTRACT To develop a user-friendly method of achieving optimal radiographs for measurement of joint space width of the knee with minimal radiation exposure. In order to accomplish this the X-ray technologist must (1) be able to identify the anterior and posterior rims of the tibial plateau at a variety of X-ray head angles and (2) be able to choose the direction to adjust the head angle to get a better view based on the criteria for acceptable radiographs.
We have developed a training manual and materials to instruct investigators and radiology technologists in a method that uses a commercially available Plexiglas positioning frame (Synaflexer) and standard X-ray equipment to achieve optimal X-rays with regard to tibial plateau alignment of the knee. This should be accomplished with four or fewer radiographs.
Optimized radiographs for joint space width measurements are achieved without the need for fluoroscopy or foot maps.
This method is readily understood and instituted by radiology technologists in the field.

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