Table 1.

MRI Based Grading of Patellofemoral Osteoarthritis

Grade	Definition
0	Normal
1	No definite osteophyte (may have other limited cartilage/bone/periarticular changes but no joint space narrowing)
2	Definite osteophyte. Focal cartilage loss without extensive involvement (i.e., no joint space narrowing)
3	Osteophyte plus significant cartilage loss involving at least one facet and/or trochlear surface (i.e., some joint space narrowing)
4	Osteophyte plus complete cartilage loss involving >50% of medial and/or lateral patellofemoral compartment (i.e., at least one surface of bone-on- bone joint space narrowing)