patella (habitual dislocation)
Last reviewed 11/2021
This is characterised by dislocation and reduction of the patella each time that respectively, the knee bends and straightens. In time, the patella may become permanently dislocated.
The most likely mechanism is contracture of the quadriceps producing abnormal tightness of the lateral structures of the knee. Possible causes include:
- trauma - causing fibrosis
- repeated intra-muscular injection
The patella dislocates laterally. Treatment is surgical. Options include one or more of:
- release of lateral structures
- tightening of medial structures
- transferral of the tibial tubercle medially to realign the pull of the quadriceps