title: Mid-term results for metaphyseal sleeves in revision knee surgery.
abstract: OBJECTIVE
  Metaphyseal titanium sleeves have been used to provide cementless fixation in challenging bone defects in revision knee arthroplasty. The aim of this study was to evaluate the mid-term results of radiological and clinical outcomes, for metaphyseal sleeves in type 1B and 2 defects of tibia and femur under the hypothesis that they would provide stable and prolonged fixation.
  
  
  METHODS
  One hundred and thirty-four patients were included in a prospective study to evaluate the outcomes of knee revision with sleeves, together with stems and varus-valgus constrained mobile bearing prosthesis. Median follow-up was 71.5 months (range 36-107). Analysis included American Knee Society Score (KSS), Western Ontario and Mcmaster Universities Osteoarthritis Index (WOMAC), SF12 Health Survey and radiographic assessment.
  
  
  RESULTS
  All clinical scores improved significantly in all patients during the follow-up. The median of Knee KSS increased from 33 to 78 and functional KSS from 30 to 80. The median of WOMAC pain index changed from 12 to 4; pre-operative median of WOMAC stiffness and WOMAC function score improved from 5 to 2 and from 45 to 14, respectively. The median of physical SF12 varied from 27 to 44, while mental SF-12 from 43 to 54. Radiological evaluation showed optimal osseous integration in all patients, and neither implant migration nor progressive radiolucency around components was observed. Complications included three cases of end-of-stem pain at tibial side and two revisions due to septic loosening in the first post-operative year. No aseptic loosening was reported.
  
  
  CONCLUSIONS
  The use of metaphyseal sleeves, in combination with uncemented stems and varus-valgus constrained components with rotating platform, has shown excellent mid-term results allowing osseous ingrowth with no evidence of osteolysis or displacement. This is a promising option for better implant fixation in revision TKA.
  
  
  METHODS
  Case series with no comparison group, Level IV.
authors.affiliation: Hospital Universitario Miguel Servet, Aragon Institute for Health Research (IIS Aragon), Paseo Isabel la Católica 1-3, 50009, Zaragoza, Spain. cmartinh@salud.aragon.es.
authors.forename: Carlos
authors.identifier: http://orcid.org/0000-0002-0858-0340
authors.initials: C
authors.lastname: Martin-Hernandez
authors.affiliation: Hospital Obispo Polanco, Avda Ruiz Jarabo S/N, 44002, Teruel, Spain.
authors.forename: Luis Javier
authors.initials: LJ
authors.lastname: Floria-Arnal
authors.affiliation: Hospital Obispo Polanco, Avda Ruiz Jarabo S/N, 44002, Teruel, Spain.
authors.forename: Maria Pilar
authors.initials: MP
authors.lastname: Muniesa-Herrero
authors.affiliation: Hospital Obispo Polanco, Avda Ruiz Jarabo S/N, 44002, Teruel, Spain.
authors.forename: Teresa
authors.initials: T
authors.lastname: Espallargas-Doñate
authors.affiliation: Hospital Obispo Polanco, Avda Ruiz Jarabo S/N, 44002, Teruel, Spain.
authors.forename: Jose Adolfo
authors.initials: JA
authors.lastname: Blanco-Llorca
authors.affiliation: Hospital Obispo Polanco, Avda Ruiz Jarabo S/N, 44002, Teruel, Spain.
authors.forename: Melchor
authors.initials: M
authors.lastname: Guillen-Soriano
authors.affiliation: Hospital Obispo Polanco, Avda Ruiz Jarabo S/N, 44002, Teruel, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Ranera-Garcia
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D005260:Female; D006801:Humans; D007720:Knee Prosthesis / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011446:Prospective Studies; D011474:Prosthesis Design; D012086:Reoperation / Q000295:instrumentation* / Q000379:methods; D014025:Titanium
chemical_list: D014025:Titanium
keywords: Cementless; Metaphyseal fixation; Revision total knee arthroplasty; Sleeves; Stability