Mid-term results for metaphyseal sleeves in revision knee surgery.

Purpose: 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.
Conclusion: 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.
Level of Evidence: Case series with no comparison group, Level IV.