Patellofemoral angle

The patellofemoral angle is a measure of patellar tilt and is useful in the diagnosis of patellofemoral instability and excessive lateral pressure syndrome. 

Measurement

The patellofemoral angle is formed between a line drawn along the bony lateral patellar facet and another line drawn along the anterior femoral condyles on axial images at the patellar mid-point ^1-3. 

Interpretation

• >0°: normal (opens laterally) ^2,3

• ≤0°: lateral patellar tilt (opens medially) ^1.3

A modified patellofemoral angle has been used by Koskinen et al measuring along the lateral patellar facet cartilage surface rather than the bony surface with an angle ≥8° or medial opening considered abnormal ^4,5.

See also

• patella tilt angle