title: Initial experience with custom-fit total knee replacement: intra-operative events and long-leg coronal alignment.
abstract: New technology using magnetic resonance imaging (MRI) allows the surgeon to place total knee replacement components into each patient's pre-arthritic natural alignment. This study evaluated the initial intra-operative experience using this technique. Twenty-one patients had a sagittal MRI of their arthritic knee to determine component placement for a total knee replacement. Cutting guides were machined to control all intra-operative cuts. Intra-operative events were recorded and these knees were compared to a matching cohort of the senior surgeon's previous 30 conventional total knee replacements. Post-operative scanograms were obtained from each patient and coronal alignment was compared to previous studies using conventional and computer-assisted techniques. There were no intra-operative or acute post-operative complications. There were no differences in blood loss and there was a mean decrease in operative time of 14% compared to a cohort of patients with conventional knee replacements. The average deviation from the mechanical axis was 1.2 degrees of varus, which was comparable to previously reported conventional and computer-assisted techniques. Custom-fit total knee replacement appeared to be a safe procedure for uncomplicated cases of osteoarthritis.
authors.affiliation: Department of Orthopedics, Memorial Hospital, York, PA, USA. brian.spencer@hotmail.com
authors.forename: Brian A
authors.initials: BA
authors.lastname: Spencer
authors.forename: Michael A
authors.initials: MA
authors.lastname: Mont
authors.forename: Mike S
authors.initials: MS
authors.lastname: McGrath
authors.forename: Bradley
authors.initials: B
authors.lastname: Boyd
authors.forename: Michael F
authors.initials: MF
authors.lastname: Mitrick
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation / Q000379:methods*; D001696:Biomechanical Phenomena; D016063:Blood Loss, Surgical / Q000517:prevention & control; D017760:Bone Malalignment / Q000000981:diagnostic imaging / Q000473:pathology / Q000517:prevention & control*; D016022:Case-Control Studies; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D007720:Knee Prosthesis; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation / Q000379:methods*; D020370:Osteoarthritis, Knee / Q000601:surgery; D011446:Prospective Studies; D011474:Prosthesis Design; D011859:Radiography; D013997:Time Factors; D016896:Treatment Outcome