---

- Discussion:
    - if patient is able to flex beyond 120 deg and if scar forms on quad tendon, this scar may be carried into notch of femoral component;
    - when the patient extends the knee (especially against resistance such as rising from a chair) the fibrotic nodule catches on the anterior
         edge of the femoral component;
         - scar eventually releases w/ a painful clunk, allowing leg to extend;
    - risk factors:
         - common in posterior stabilized TKR;
         - patella infera is a risk factor;

- Clinical Presentation:
    - pt may report loosening, dislocation, or giving out because the patella catches during extension and tracks roughly;

- Treatment:
    - arthroscopic resection of the offending scar tissue

---

Arthroscopic managment of the patellar clunk syndrome following posterior stabilized total knee arthroplasty.

The patellar clunk syndrome: A complication of posterior stabilized total knee arthroplasty. 

Synovial Entrapment: A Complication of Posterior Stabilized Total Knee Arthroplasty.

The patellar "clunk" syndrome after posterior stabilized total knee arthroplasty.

Intra-articular fibrous bands. Patellar complications after total knee replacement.