Patient-specific cutting guides for total knee arthroplasty

Background. The incidence of malalignment in total knee arthroplasty(TKA) using conventional instrument has beenreported as high as 25%. A relatively new TKA system involvesthe use of a preoperative magnetic resonance image(MRI) to obtain accurate implant placement more consistently.For broad acceptance of this new technique, it iscrucial to analyze the initial intra-operative experience. Thespecific aim of this study was to evaluate the initial intra-operativeexperience of a single surgeon using this new technique. Methods. A total of 15 knees (12 patients: 6 female and 6male) were reviewed from TKA procedures using the selectedmanufacturer’s patient specific cutting guides between January2011 and April 2013 at a single institution. Patient demographicand specific parameters and intra-operative alterationsof component positioning were recorded and evaluated.Results. The preoperative plan was able to predict correctly thesize of the implanted femoral component in 87% (n = 13) andtibial component in 80% (n = 12) of the cases. However, 60% (n= 9) of cases required additional intra-operative corrections onfemoral resection, and 73% (n = 11) required an additional 2 - 4mm correction on the tibial proximal resection. Twenty percent(n = 3) required additional tibial varus/valgus correction, butthere were no tibial slope corrections for any of the 15 cases. Conclusions. The initial intra-operative experience of a singlesurgeon using current patient specific cutting guides for a selectedmanufacturer to align femoral and tibial components duringTKA has raised some concerns. We agreed with previous studiesthat caution should be taken when using patient specific cuttingguides without supportive data. The findings of this study providedadditional evidence to contest the accuracy of patient specificcutting guides with respect to the initial experience of an orthopaedicsurgeon who is trained in total joint replacement. Theresults provided more evidence to assist orthopaedic surgeonsin the decision of whether to use these patient specific systemsversus conventional TKA methods. KS J Med 2016;9(2):22-26.

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Handheld Navigation Device and Patient-Specific Cutting Guides Result in Similar Coronal Alignment for Primary Total Knee Arthroplasty: a Retrospective Matched Cohort Study

HSS Journal ® ◽

10.1007/s11420-015-9484-2 ◽

2016 ◽

Vol 12 (3) ◽

pp. 224-234 ◽

Cited By ~ 8

Author(s):

Michael E. Steinhaus ◽

Alexander S. McLawhorn ◽

Shawn S. Richardson ◽

Patrick Maher ◽

David J. Mayman

Keyword(s):

Total Knee Arthroplasty ◽

Cohort Study ◽

Knee Arthroplasty ◽

Primary Total Knee Arthroplasty ◽

Patient Specific ◽

Matched Cohort ◽

Coronal Alignment ◽

Cutting Guides ◽

Total Knee ◽

Primary Total Knee

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Contribution of patient-specific cutting guides to lower limb alignment for total knee arthroplasty

Orthopaedics & Traumatology Surgery & Research ◽

10.1016/j.otsr.2014.03.006 ◽

2014 ◽

Vol 100 (4) ◽

pp. S239-S242 ◽

Cited By ~ 8

Author(s):

H. Moubarak ◽

J. Brilhault

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Lower Limb ◽

Patient Specific ◽

Limb Alignment ◽

Lower Limb Alignment ◽

Cutting Guides ◽

Total Knee

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Comparison of Postoperative Coronal Leg Alignment in Customized Individually Made and Conventional Total Knee Arthroplasty

Journal of Personalized Medicine ◽

10.3390/jpm11060549 ◽

2021 ◽

Vol 11 (6) ◽

pp. 549

Author(s):

Felix Wunderlich ◽

Maheen Azad ◽

Ruben Westphal ◽

Thomas Klonschinski ◽

Patrick Belikan ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Weight Bearing ◽

Postoperative Outcome ◽

Patient Specific ◽

Target Zone ◽

Leg Alignment ◽

Conventional Instrumentation ◽

Cutting Guides ◽

Total Knee

Neutral coronal leg alignment is known to be important for postoperative outcome in total knee arthroplasty (TKA). Customized individually made implants (CIM) instrumented with patient-specific cutting guides are an innovation aiming to increase the precision and reliability of implant positioning and reconstruction of leg alignment. We aimed to compare reconstruction of the hip–knee–ankle angle (HKA) of the novel CIM system iTotal™ CR G2 (ConforMIS Inc.) to a matched cohort of the off-the-shelf (OTS) knee replacement system Vanguard™ CR (Zimmer Biomet). Retrospective analysis of postoperative coronal full-leg weight-bearing radiographs of 562 TKA (283 CIM TKA, 279 OTS TKA) was conducted. Via a medical planning software, HKA and rotation of the leg were measured in postoperative radiographs. HKA was then adjusted for rotational error, and 180° ± 3° varus/valgus was defined as the target zone HKA. Corrected postoperative HKA in the CIM group was 179.0° ± 2.8° and 179.2° ± 3.1° in the OTS group (p = 0.34). The rate of outliers, outside of the ±3° target zone, was equal in both groups (32.9%). Our analysis showed that TKA using patient-specific cutting guides and implants and OTS TKA implanted with conventional instrumentation resulted in equally satisfying restoration of the coronal leg alignment with less scattering in the CIM group.

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Accuracy of bone resection in total knee arthroplasty using CT assisted-3D printed patient specific cutting guides

SICOT-J ◽

10.1051/sicotj/2018032 ◽

2018 ◽

Vol 4 ◽

pp. 29 ◽

Cited By ~ 3

Author(s):

Ikram Nizam ◽

Ashish V. Batra

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Patient Specific ◽

Surgical Patient ◽

Bone Resection ◽

Patient Specific Instrumentation ◽

Medial Pivot ◽

Cutting Guides ◽

3D Printed ◽

Total Knee

Introduction: We conducted this study to determine if the pre-surgical patient specific instrumented planning based on Computed Tomography (CT) scans can accurately predict each of the femoral and tibial resections performed through 3D printed cutting guides. The technique helps in optimization of component positioning determined by accurate bone resection and hence overall alignment thereby reducing errors. Methods: Prophecy evolution medial pivot patient specific instrumented knee replacement systems were used for end stage arthrosis in all consecutive cases over a period of 20 months by a single surgeon. All resections (4 femoral and 2 tibial) were measured using a vernier callipers intraoperatively. These respective measurements were then compared with the preoperative CT predicted bone resection surgical plan to determine margins of errors that were categorized into 7 groups (0 mm to ≥2.6 mm). Results: A total of 3618 measurements (averaged to 1206) were performed in 201 knees (105 right and 96 left) in 188 patients (112 females and 76 males) with an average age of 67.72 years (44 to 90 years) and average BMI of 32.3 (25.1 to 42.3). 94% of all collected resection readings were below the error margin of ≤1.5 mm of which 90% showed resection error of ≤1 mm. Mean error of different resections were ≤0.60 mm (P ≤ 0.0001). In 24% of measurements there were no errors or deviations from the templated resection (0.0 mm). Conclusion: The 3D printed cutting blocks with slots for jigs accurately predict bone resections in patient specific instrumentation total knee arthroplasty which would directly affect component positioning.

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