Tibial plateau coverage in UKA: a comparison of patient specific and off-the-shelf implants.
Poor tibial component fit can lead to issues including pain, loosening and subsidence. Morphometric data, from 30 patients undergoing UKA were utilized; comparing size, match and fit between patient-specific and off-the-shelf implants. CT images were prospectively obtained and implants modeled in CAD, utilizing sizing templates with off-the-shelf and CAD designs with patient-specific implants. Virtual surgery was performed, maximizing tibial plateau coverage while minimizing implant overhang. Each implant evaluated to examine tibial fit. Patient-specific implants provided significantly greater cortical rim surface area coverage versus off-the-shelf implants: 77% v. 43% medially and 60% v. 37% laterally. Significantly less cortical rim overhang and undercoverage were observed with patient-specific implants. Patient-specific implants provide superior cortical bone coverage and fit while minimizing overhang and undercoverage seen in off-the-shelf implants.
University of Arkansas for Medical Sciences, Little Rock, Arkansas.
Dylan P
DP
Carpenter
CONFORMIS, Inc., Bedford, Massachusetts.
Rebecca R
RR
Holmberg
CONFORMIS, Inc., Bedford, Massachusetts.
Marc J
MJ
Quartulli
HipKnee Arkansas Foundation, Little Rock, Arkansas.
C Lowry
CL
Barnes
D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation* / Q000379:methods*; D003198:Computer Simulation; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D007720:Knee Prosthesis; D011474:Prosthesis Design; D017755:Prosthesis Fitting; D013977:Tibia / Q000000981:diagnostic imaging / Q000601:surgery*; D014057:Tomography, X-Ray Computed
CT-based imaging; ConforMIS; overhang; patient specific implants; tibial component; unicompartmental knee arthroplasty