Comparison of inset and resurfacing patellar prostheses in total knee arthroplasty.
A comparison of 135 resurfacing with 116 inset biconvex patellar components with a single total knee arthroplasty design was performed. At 2.5 +/- 0.5 years postoperatively, patellar tilt in the resurfacing group was 4 degrees +/- 6 degrees compared with 0.5 degree +/- 5 degrees in the biconvex group (p < 0.0001). Lateral patellar subluxation was 6% +/- 10% in the resurfacing group compared with 3% +/- 9% in the biconvex group (p < 0.05). Lateral release was required in 79% of the resurfacing group compared with 56% in the biconvex group (p < 0.0001). Complete patellar radiolucent lines were seen adjacent to 4 biconvex and 2 resurfacing patellar prostheses. Patellar radiolucent lines were seen more frequently in area 1 in the biconvex group compared with the resurfacing group (p < 0.01). An inset patellar implant appears to provide better radiographic alignment than a resurfacing implant, but it has a higher incidence of radiolucent lines.
Rand
J A
JA
Department of Orthopedic Surgery, Mayo Clinic Scottsdale, Scottsdale, Arizona 85259, USA.
Gustilo
B
B
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000502:physiology; D007720:Knee Prosthesis / Q000379:methods*; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010329:Patella / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D011183:Postoperative Complications / Q000209:etiology; D011474:Prosthesis Design; D011859:Radiography; D016059:Range of Motion, Articular; D012086:Reoperation