Comparison of custom to standard TKA instrumentation with computed tomography

Abstract

When evaluated with CT, custom instrumentation performs similar or better to standard instrumentation in component alignment and accurately templates component size. Tourniquet time was mildly increased for custom compared to standard.

Important Differences Exist in Posterior Condylar Offsets in an Osteological Collection of 1,058 Femurs

“…In accord with earlier studies, we would argue that the use of a unisex prosthesis to recreate posterior condylar anatomy is likely sufficient [22]. Other custom implants have attempted to account for differences in PCO by varying the size of medial and lateral posterior condyles; most authors agree that more longterm follow-up is needed to determine the potential benefits of such systems [28][29][30]. However, in light of the differences discussed above, TKA designs should consider including a more posteriorly offset medial posterior condyle to address this known osteological difference.…”

Patient specific guides for total knee arthroplasty are ready for primetime

“…Most of the outcomes are comparable, however, 2 articles published significant better outcome with extramedular rods [25,26] . Only Ng et al [22] found significant better outcome with MRI based PSG for the tibia. LevelⅠ results are very remarkable in regard to the LTC.…”

“…This perioperative guiding technique eliminates the use of intra-and extra medullar rods to make bony resections. Previous published results on PSG suggest this to be a good alternative to conventional instrumentation with comparable results, improved radiological outcome and reduced operation time and blood loss [7,[13][14][15][16][17][18][19][20][21][22][23] . This prospective study on PSG between different manufacturers and conventional technique for the implantation of TKA was designed to address the following research questions: Is there a significant difference in outliers in alignment in the frontal and lateral plane between PSG and conventional TKA, secondly between the four individual different PSG systems and thirdly between cut-and pin PSG?…”

“…Despite a good ICC for the evaluation of the frontal and lateral position of both femur and tibia implants, rotational alignment was not examined. Most of the literature use long-standing radiographs, except for 1 paper which used scout CT scan [17] and two used full-leg CT scans [22,27] . Postoperative evaluation on 3D-CT have shown to be a valuable tool to measure position and orientation of both the femur and tibia components and it is more accurate with significantly better femoral rotation alignment after use of PSG [18,22,32] .…”

“…To summarize, PSG from different manufacturer can be an added value in daily Boonen et al [16] Signature MRI Intra X-ray 90/90 LFC (49/65) 1 Chareancholvanich et al [17] PSI MRI Intra/Extra X-ray and CT 40/40 FFC (0/18) 1 Chotanaphuti et al [18] TruMatch CT Intra/Extra X-ray and CT 40/40 NA Hamilton et al [19] TruMatch Scout CT Intra/Extra X-ray 26/26 LTC (65/50) 2 Ng et al [22] [Outliers Kotela et al [26] Signature CT Intra/Extra X-ray 49/46 FTC (39/20) 1 Woolson et al [27] TruMatch CT Intra/Extra CT …”