Patient specific cutting blocks are currently of no proven value

Abstract

Patient specific cutting guides generated by preoperative Magnetic Resonance Imaging (MRI) of the patient's extremity have been proposed as a method of improving the consistency of Total Knee Arthroplasty (TKA) alignment and adding efficiency to the operative procedure. The cost of this option was evaluated by quantifying the savings from decreased operative time and instrument processing costs compared to the additional cost of the MRI and the guide. Coronal plane alignment was measured in an unselected consecutive series of 200 TKAs, 100 with standard instrumentation and 100 with custom cutting guides. While the cutting guides had significantly lower total operative time and instrument processing time, the estimated $322 savings was overwhelmed by the $1,500 additional cost of the MRI and the cutting guide. All measures of coronal plane alignment were equivalent between the two groups. The data does not currently support the proposition that patient specific guides add value to TKA.

The Mark Coventry Award: Custom Cutting Guides Do Not Improve Total Knee Arthroplasty Clinical Outcomes at 2 Years Followup

“…Although Noble et al [24] noted a decrease in operative times with the use of CCGs by 7 minutes, Hamilton et al [17] found the use of traditional instrumentation to be shorter than CCGs by 4 minutes. In addition, the results of several Level II and Level II studies have also been mixed to this regard [6,8,11,25]. No difference in either tourniquet time or total operative time was seen in our study.…”

“…Occasionally, seating of the CCGs was difficult, and thus surgeons took an increased amount of time to confirm that the blocks were seated correctly. Furthermore, a prior cost-analysis study showed any potential savings in operating room efficiency would be greatly outweighed by the current cost of the preoperative MRI and cutting guide fabrication (approximately USD 1500) [6]. Thus, because no difference in surgical times nor radiologic outcomes was noted in our study, the potential financial benefits of improved surgical efficiency and accuracy may not be realized with the use of CCGs [33,39].…”

“…With regard to component and overall alignment, studies have failed to consistently demonstrate an improved accuracy with the use of CCGs versus standard instrumentation [6,11,18,24,40]. Furthermore, the costeffectiveness of this technology has not been proven, because the potentially decreased operative times and instrument trays required might not offset the additional costs of preoperative imaging and CCG fabrication [6,33,39]. To date, small cohorts and short followup have limited studies assessing the actual clinical outcomes of CCGs.…”

“…Numerous potential benefits of CCGs exist compared with both standard and computer-assisted surgical instrumentation, including their ease of use; a decrease in operative times and instrument trays; the ability to preoperatively plan for component size, alignment, and position; and an improvement in postoperative alignment versus the use of standard alignment methods [4,18,23]. However, to date the majority of reports have not confirmed these proposed benefits [6,11,33,37,39,41].…”

CORR Insights®: Is TKA Using Patient-specific Instruments Comparable to Conventional TKA? A Randomized Controlled Study of One System

“…The work of Parratte et al [3] suggests that a neutral mechanical axis may not be necessary for longevity in TKA. The inability to complete surgeries using patient-specific guides remains an issue, particularly given the cost for imaging and creation of the guides [1]. While we trust the judgment of an experienced surgeon in abandoning the approach, we ask whether the apparent rotational malalignment determined visually by comparison to gap balancing was an accurate reflection of a true mismatch (the appearance of a trapezoidal flexion space), or whether the guide represented the CT derived ''true'' alignment of the knee?…”