title: Subchondral Bone Marrow Edema Had Greater Effect on Postoperative Pain After Medial Unicompartmental Knee Arthroplasty Than Total Knee Arthroplasty.
abstract: BACKGROUND
  Although the relationship between pain and bone marrow edema (BME) in the osteoarthritic knee has been established, little is known about the effect of preoperative BME on postoperative outcomes after knee arthroplasty or if the influence of BME on postoperative outcomes differs between medial unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA). The purpose of this study was to compare pain, patient satisfaction, and revision rates between medial UKA and TKA patients with and without magnetic resonance imaging evidence of BME in the proximal tibia.
  
  
  METHODS
  We identified 71 patients (72 knees) from our prospective outcomes database with magnetic resonance images taken before undergoing either medial UKA or TKA and recorded the absence or presence of tibial BME. We then compared preoperative and postoperative Knee Society pain scores, patient satisfaction, and revisions between groups of UKA and TKA patients with or without preoperative tibial BME.
  
  
  RESULTS
  Pain scores for UKA patients with BME were worse both before and after surgery, whereas TKA patients with BME demonstrated greater postoperative improvements in pain scores when compared to TKA patients without BME. Similarly, significantly fewer UKA patients with BME were satisfied with their procedure than those without BME (8/11, 73% vs 17/17, 100%; P = .05), but BME did not affect patient satisfaction after TKA.
  
  
  CONCLUSIONS
  Preoperative BME did not influence TKA outcomes; however, pain scores for UKA patients with BME were worse both before and after surgery and fewer UKA patients with preoperative tibial BME were satisfied with their surgery.
authors.affiliation: Lexington Clinic, Lexington, Kentucky.
authors.forename: Cale A
authors.initials: CA
authors.lastname: Jacobs
authors.affiliation: Lexington Clinic, Lexington, Kentucky.
authors.forename: Christian P
authors.initials: CP
authors.lastname: Christensen
authors.affiliation: Lexington Clinic, Lexington, Kentucky.
authors.forename: Tharun
authors.initials: T
authors.lastname: Karthikeyan
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects* / Q000379:methods; D001853:Bone Marrow; D001855:Bone Marrow Diseases / Q000209:etiology*; D016208:Databases, Factual; D004487:Edema / Q000209:etiology*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010149:Postoperative Pain / Q000209:etiology*; D017060:Patient Satisfaction; D011184:Postoperative Period; D011446:Prospective Studies; D012042:Registries; D012086:Reoperation; D013977:Tibia / Q000601:surgery
keywords: arthroplasty; bone marrow lesion; knee; pain; patient satisfaction