PATHOLOGY
Advanced patellofemoral arthritis
TREATMENT
Patellofemoral arthroplasty
SUBMITTED BY
Tom Minas, MD, and Tim Bryant, RN, Cartilage Repair Center, Brigham and Women's Hospital, Chestnut Hill, Massachusetts, USA
CHIEF COMPLAINT AND
HISTORY OF PRESENT ILLNESS
The patient is a 41-year-old man with a long- standing history of anterior right knee pain. As a teenager he sustained a patellar dislocation with an osteoarticular fracture. An open VMO quadriceps repair and removal of loose body was performed. Since then, five further arthro- scopic debridements have been performed.
Presently he complains of chronic right anterior knee pain. He uses antiinflammatories and ice for pain management only. He has pain that awakens him at night when he rolls over in bed.
He is able to walk better on level surfaces than on inclines or up and down stairs. Additionally, he must use a handrail one step at a time to ascend or descend the stairs. He has frequent activity-related effusions. He requests a defini- tive operation that will relieve him of his pain and allow him to rapidly return to work to support his family. His job does not require physical or labor-intensive activities.
PHYSICAL EXAMINATION
Height, 6ft, lin.; weight, 2101b. Clinical exami- nation demonstrates a relatively fit 41-year-old man with clinically neutral ahgnment. He walks with an antalgic gait. He must use his hands to get out of a seated position; he is unable to crouch or squat. His range of motion is from 0
to 125 degrees of flexion. Other findings include severe patellofemoral crepitation, a large joint effusion, and a relatively normal quadriceps angle of 15 degrees. His ligament and meniscal examination is unremarkable.
RADIOGRAPHIC EVALUATION
Standing radiographs demonstrate a well-maintained tibiofemoral joint space. Radi- ographs demonstrate a narrowed patello- femoral joint space (Figure C25.1).
SURGICAL INTERVENTION
At arthrotomy, the tibiofemoral articulations were intact. The patellofemoral joint demon- strated severe erosive grade IV changes to the trochlea and the patella with a convex hypoplastic trochlea (Figure C25.2). A patellofemoral arthroplasty was performed (Figure C25.3). Postoperatively, the patient advanced readily to weight bearing and range of motion as tolerated.
FOLLOW-UP
Within 3 weeks of his patellofemoral prosthe- sis, the patient was pain free and returned to work. Two years after implantation, he remains satisfied with the result.
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FIGURE C25.1. Preoperative plain standing anteroposterior (A) and skyline (B) radiographs demonstrate normal tibiofemoral joint space with central and lateral patellofemoral compartment joint space narrowing.
FIGURE C25.2. Appearance at the time of open arthrotomy. The trochlea is convex, hypoplastic, and has severe erosive changes. Similarly, the patella has
a large area of exposed bone and has a dysplastic concave appearance.
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FIGURE
