Results of an independent, prospective study of ConforMIS' iTotal CR Knee in the restoration of coronal plane mechanical axis alignment suggest that use of a patient-specific custom knee plus patient-specific instrumentation yields more consistently-accurate results than those found with use of patient-specific cutting guides and off-the-shelf implants.
Of 63 consecutive patients receiving iTotal CR with iJig instrumentation, 84% achieved a reported perfect neutral coronal mechanical alignment of 0°, with the remaining 16% within +/-2° of neutral. Further, while 40 patients had pre-op extension deficits, none had post-op extension deficits.
According to this study, neutral mechanical limb alignment has been linked to better survivorship in total knee arthroplasty, while poor alignment has been linked to higher rates of implant failure. This study’s findings are consistent with those of a 2014 published study which concluded that iTotal was 1.8x more likely to achieve a neutral mechanical alignment vs. standard, off-the-shelf knees.
In other analyses comparing iTotal CR to standard implants, iTotal has been found more likely to have an excellent or good objective Knee Society Score; more natural knee kinematics and greater patient satisfaction at one year.
Sources: ConforMIS, Inc.; ORTHOWORLD Inc.