Patella alta is when the patella sits higher than normal. This often lead to arthritis and is a risk factor for patellar instability. In this study (done at the Rothman Orthopaedic Institute), they compared the amount of cartilage damage in patients undergoing patellar realignment surgery.
They found less damage in patients with patella alta than in those with patellas sitting at a normal height. While this is interesting, it doesn’t help us make decisions. That is, I wouldn’t suggest to a patient to treat their patellar instability non-operatively just because they have patella alta. Nor would I recommend that patients with normal alignment be treated for a first time dislocation more aggressively.
The best approach is to assess all risk factors for recurrence and recommend surgery early enough to avoid cartilage damage.
Read the complete study on Healio: Patients with patella alta may experience less severe cartilage damage after instability.