Surgical Treatment of Iatrogenic Patella Baja

Patella baja caused by a prior surgery develops when scarring and adhesions just below the kneecap pull it downward. It happens most often after ACL reconstruction with a bone-patellar tendon-bone graft, high tibial osteotomy, tibial tubercle osteotomy, or total knee replacement. Quad weakness, long periods in a brace, and inflammation after surgery all contribute. The lower kneecap position affects the system that straightens the knee, and imaging confirms the diagnosis using a specific height ratio.

Patients with patella baja typically have limited knee range of motion, front-of-knee pain, weakness with active knee straightening, and an extensor lag (where the leg can't fully straighten under power). Symptoms often appear weeks to months after the original injury or surgery. Some patients also feel that the kneecap sits too low and may have grinding sensations when bending the knee. Imaging confirms the diagnosis.

Surgical options include moving the kneecap tendon attachment higher on the shinbone, lengthening the kneecap tendon, and reconstructing the kneecap tendon. Donor or your own tissue may be used to augment the lengthening or reconstruction. The choice depends on the cause, the severity of the kneecap-height loss, the condition of the tendon system that straightens the knee, and whether prior hardware needs to be addressed. Surgery is reserved for patients with symptoms — limited motion, front-of-knee pain, or weakness on straightening — not for incidental findings on imaging alone.