This site is targeted at medical and radiology professionals, contains user contributed content, and material that may be confusing to a lay audience. Use of this site implies acceptance of our Terms of Use.

Patella alta

A patella alta (or a high riding patella) describes a situation where the position of patella is considered high. It may be idiopathic or may result secondary to a patellar tendon rupture

Associations

Several conditions are known to be associated with patella alta, including:

  • idiopathic retro-patellar pain 5
  • recurrent dislocation of the patella 2
  • chondromalacia patellae 2
  • knee joint effusion 2

Patella alta may also occur as a result of spastic cerebral palsy 6.

Radiographic features

On sagittal images it is usually considered when the Insall-Salvati ratio is greater than 1.3 - 1.5 1-3.

On radiography, it is important that standard positioning is used, with the knee flexed at 30 degrees. An off-angle x-ray beam or nonstandard positioning may result in a spuriously abnormal ratio.

Updating… Please wait.
Loadinganimation

Alert_accept

Error Unable to process the form. Check for errors and try again.

Alert_accept Thank you for updating your details.