Understanding Patella Baja in Total Knee Arthroplasty

Understanding Patella Baja in Total Knee Arthroplasty, Avoiding a Roadblock in Recovery

Patella baja is an abnormally low-lying patella or decreased space

between the inferior pole of the patella and the tibial tubercle

Previous knee surgeries Measurement of patellar height

Anterior cruciate ligament reconstruction Insall-Salvati ratio

Retrograde femoral nail

Infrapatellar fat pad resection

Previous total knee arthroplasty

Determining the etiology will help guide appropriate treatment for patella baja after total knee arthroplasty

Etiology Diagnosis

Treatment

It is an uncommon yet disabling condition of total knee arthroplasty

Surgery

Impingement PainDecreased range of motion

Recovery

Patella baja

Leads to

Blackburne-Peel ratio

Distinction from pseudopatella baja

Tibial tubercle

osteotomy

Distal femoral augment and

revision

Proximalization of patellar component

Modification of anterior tibial component

Z-plasty of patellar tendon

A

A=0.8-1.2

B

B

A

A=0.5-1.0

B

B

A

B

Lum et al. (2020) DOI: 10.5435/JAAOS-D-19-00422

Patella Baja in Total Knee Arthroplasty