Arthroscopy in the diagnosis of occult dislocation of the patella.

@article{Casteleyn1989ArthroscopyIT,
  title={Arthroscopy in the diagnosis of occult dislocation of the patella.},
  author={P. P. Casteleyn and Frank Handelberg},
  journal={Acta orthopaedica Belgica},
  year={1989},
  volume={55 3},
  pages={381-3}
}
The authors investigated the incidence of acute patellar dislocation by clinical and radiologic examination and by arthroscopy. Acute patellar dislocation represented 2.44% of all knee injuries in their series, and only 25% of the former were evident at the initial examination.