Glossary
Patella alta
Quick answer
Patella alta means the kneecap sits higher than normal on the front of the knee, usually because the patellar tendon is long. A high kneecap engages its groove later as the knee bends, making it more likely to slip out, explains Doha knee surgeon Dr. Pablo Gelber at Aman Hospital.
What it means
Alta is Latin for high. On a side-on X-ray or MRI the radiologist compares the length of the patellar tendon with the height of the kneecap, using ratios such as Insall-Salvati or Caton-Deschamps. A ratio above the normal range is reported as patella alta.
It is often something you are born with, and it can run in families. It is more common in people with general joint hypermobility.
Why it matters
In the first part of bending, the kneecap should slide into the trochlear groove at the end of the thigh bone, which holds it in place. A high kneecap stays above the groove for longer and has less bony support, so a twist or awkward landing can push it out.
Patella alta is one of the main risk factors, alongside trochlear dysplasia and a torn MPFL, for repeated kneecap dislocations. It can also contribute to front-of-knee pain.
How it is treated
If you have never dislocated, no treatment is needed. After a first dislocation, physiotherapy is usually first-line. For recurrent dislocations, MPFL reconstruction is commonly performed, and when alta is marked a tibial tubercle osteotomy can move the tendon attachment down to bring the kneecap into its groove sooner.
Frequently asked questions
Is patella alta dangerous?
No. It is a variation in anatomy, not a disease. It matters mainly if your kneecap has dislocated or you have kneecap pain.
Can exercise lower the kneecap?
No, exercise cannot change the kneecap height. Strengthening improves control and can reduce symptoms, but it does not alter the anatomy.
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