Patella tooth sign

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Patella tooth sign refers to vertical ridging of the patellar insertion of the quadriceps tendon which can resemble a dentate structure, i.e. "tooth" sign.

Clinical presentation

No correlation with patient's clinical symptoms.

Radiographic features

  • frequent finding with degenerative disease
  • degenerative enthesophyte formation on superior aspect of patella (site of insertion of the quadriceps tendon) as seen on axial or skyline (sunrise) view
  • seen as saw-tooth projections: best seen on axial or skyline view of patella on its superior and anterior surface