Grading of joint osteoarthritis by Ahlbäck uses plain postero-anterior weight-bearing radiographs to assess the extent of degenerative disease as joint space narrowing and bone attrition.

Grading of joint osteoarthritis by Kellgren and Lawrence uses plain radiograph to assess the extent of degenerative disease. Originally, the authors assessed degenerative joint disease on a single x-ray view: AP for hips, knees, and feet, lateral view for cervical and lumbar spine, and PA view for hands. In the following studies, several mutations of this classification were used.