title: Implant Design and Effects on Patellofemoral Crepitus.
abstract: BackgroundPatellofemoral crepitus is a known complication of posterior stabilized (PS) total knee arthroplasty (TKA). This study compared the incidence of patellofemoral crepitus between two femoral components designs.Materials and MethodsBetween January 2005 and August 2010, 1,120 patients with complete 2-year follow-up had a PS TKA with two different prosthetic designs (group A, 553 patients; group B, 567 patients). Records were reviewed to identify the incidence of total, symptomatic, and operative patellofemoral crepitus.ResultsNo statistical differences were observed in the incidence of total patellofemoral crepitus (group A 14.1%, group B 14.5%;p= 0.932) or symptomatic patellofemoral crepitus (group A 5.6%, group B 4.2%;p= 0.334). The incidence of operative crepitus was greater in group A (3.3%) than in group B (1.3%;p= 0.026). Analysis of mobile versus fixed bearing designs showed a higher incidence of total patellofemoral crepitus in mobile bearing TKA (16.04 vs. 4.93%;p= 0.006) within group B only.ConclusionFemoral component design with a smoother intercondylar box transition zone resulted in a lower incidence of operative patellofemoral crepitus. No statistical differences were noted regarding the incidence of total and symptomatic patellofemoral crepitus. Mobile bearing TKA exhibited greater total crepitus within group B.Level of EvidenceLevel III.
authors.affiliation: Department of Orthopedic Surgery, Raleigh Orthopaedic Clinic, Raleigh, North Carolina.
authors.forename: David Clinton
authors.initials: DC
authors.lastname: McNabb
authors.affiliation: Department of Colorado Joint Replacement, Porter Adventist Hospital Ringgold Standard Institution, Denver, Colorado.|Department of Biomedical Engineering, University of Denver Ringgold Standard Institution, Denver, Colorado.|Department of Biomedical Engineering, University of Tennessee Ringgold Standard Institution, Knoxville, Tennessee.|Department of Orthopedics, University of Colorado Denver School of Medicine Ringgold Standard Institution, Aurora, Colorado.
authors.forename: Douglas A
authors.initials: DA
authors.lastname: Dennis
authors.affiliation: Department of Colorado Joint Replacement, Porter Adventist Hospital Ringgold Standard Institution, Denver, Colorado.
authors.forename: Jason M
authors.initials: JM
authors.lastname: Jennings
authors.affiliation: Department of Orthopedics, Sierra Vista Medical Group, Sierra Vista, Arizona.
authors.forename: Brian
authors.initials: B
authors.lastname: Daines
authors.affiliation: Department of Biomedical Engineering, University of Denver Ringgold Standard Institution, Denver, Colorado.
authors.forename: Peter
authors.initials: P
authors.lastname: Laz
authors.affiliation: Department of Colorado Joint Replacement, Porter Adventist Hospital Ringgold Standard Institution, Denver, Colorado.|Department of Mechanical and Materials Engineering, University of Denver, Denver, Colorado.|Department of Orthopedic Surgery, Joan C Edwards School of Medicine at Marshall University Ringgold Standard Institution, Huntington, West Virginia.
authors.forename: Raymond H
authors.initials: RH
authors.lastname: Kim
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects* / Q000295:instrumentation*; D005260:Female; D005269:Femur / Q000601:surgery; D006801:Humans; D015994:Incidence; D007592:Joint Diseases / Q000453:epidemiology* / Q000601:surgery; D007719:Knee Joint / Q000601:surgery; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology*; D011474:Prosthesis Design / Q000009:adverse effects*; D012189:Retrospective Studies