title: Lateral patellar facet impingement after primary total knee arthroplasty: it does exist.
abstract: The existence of the diagnosis "lateral patellar facet impingement" (LPFI) is controversial and the outcomes for surgical revision for symptomatic LPFI uncertain. We found that of the 3361 index knee revisions performed at our institution from 1995 to 2008, eleven were done for symptomatic LPFI. Their clinical histories and radiographic imaging were reviewed before and after revision TKA and were also compared to a group of control patients. We found no statistically significant differences between the groups in preoperative KS pain and function scores or radiographic features. However, the combined findings of pain in the subpatellar/lateral aspect of the knee post TKA and radiographic lateral facet contact were significantly associated with revision due to LPFI. Surgical revision results were variable, but~2/3 of the patients were satisfied with the operation and had a significant improvement in KS function scores.
authors.affiliation: Mayo Clinic, Rochester, Minnesota.
authors.forename: O Brant
authors.initials: OB
authors.lastname: Nikolaus
authors.affiliation: Mayo Clinic, Rochester, Minnesota.
authors.forename: Dirk R
authors.initials: DR
authors.lastname: Larson
authors.affiliation: Mayo Clinic, Rochester, Minnesota.
authors.forename: Arlen D
authors.initials: AD
authors.lastname: Hanssen
authors.affiliation: Mayo Clinic, Rochester, Minnesota.
authors.forename: Robert T
authors.initials: RT
authors.lastname: Trousdale
authors.affiliation: Mayo Clinic, Rochester, Minnesota.
authors.forename: Rafael J
authors.initials: RJ
authors.lastname: Sierra
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007592:Joint Diseases / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D057071:Patellofemoral Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D011859:Radiography; D012086:Reoperation
keywords: lateral patellar facet impingement (LPFI); patellofemoral joint; total knee arthroplasty