Kinematic Alignment With Image-Based Robotic Instrumentation

2022 ◽  
pp. 50-59
Author(s):  
Tilman Calliess ◽  
Bernhard Christen
Keyword(s):  
Kinematic Alignment

scholarly journals True Kinematic Alignment Is Applicable in 44% of Patients Applying Restrictive Indication Criteria—A Retrospective Analysis of 111 TKA Using Robotic Assistance

2021 ◽  
Vol 11 (7) ◽  
pp. 662
Author(s):  
Kim Huber ◽  
Bernhard Christen ◽  
Sarah Calliess ◽  
Tilman Calliess
Keyword(s):  
Soft Tissue ◽  
Retrospective Analysis ◽  
Patient Specific ◽  
Kinematic Alignment ◽  
Postoperative Phase ◽  
Robotic Assistance ◽  
Component Position ◽  
Joint Stability ◽  
Robotic Assisted ◽  
Primary Tkas

Introduction: Image-based robotic assistance appears to be a promising tool for individualizing alignment in total knee arthroplasty (TKA). The patient-specific model of the knee enables a preoperative 3D planning of component position. Adjustments to the individual soft-tissue situation can be done intraoperatively. Based on this, we have established a standardized workflow to implement the idea of kinematic alignment (KA) for robotic-assisted TKA. In addition, we have defined limits for its use. If these limits are reached, we switch to a restricted KA (rKA). The aim of the study was to evaluate (1) in what percentage of patients a true KA or an rKA is applicable, (2) whether there were differences regarding knee phenotypes, and (3) what the differences of philosophies in terms of component position, joint stability, and early patient outcome were. Methods: The study included a retrospective analysis of 111 robotic-assisted primary TKAs. Based on preoperative long leg standing radiographs, the patients were categorized into a varus, valgus, or neutral subgroup. Initially, all patients were planned for KA TKA. When the defined safe zone had been exceeded, adjustments to an rKA were made. Intraoperatively, the alignment of the components and joint gaps were recorded by robotic software. Results and conclusion: With our indication for TKA and the defined boundaries, “only” 44% of the patients were suitable for a true KA with no adjustments or soft tissue releases. In the varus group, it was about 70%, whereas it was 0% in the valgus group and 25% in the neutral alignment group. Thus, significant differences with regard to knee morphotypes were evident. In the KA group, a more physiological knee balance reconstructing the trapezoidal flexion gap (+2 mm on average laterally) was seen as well as a closer reconstruction of the surface anatomy and joint line in all dimensions compared to rKA. This resulted in a higher improvement in the collected outcome scores in favor of KA in the very early postoperative phase.

Adjusting Insert Thickness and Tibial Slope Do Not Correct Internal Tibial Rotation Loss Caused by PCL Resection: In Vitro Study of a Medial Constraint TKA Implanted with Unrestricted Calipered Kinematic Alignment

2021 ◽  
Author(s):  
Alexander J. Nedopil ◽  
Peter J. Thadani ◽  
Thomas H. McCoy ◽  
Stephen M. Howell ◽  
Maury L. Hull
Keyword(s):  
Internal Rotation ◽  
Cruciate Ligament ◽  
Tibial Slope ◽  
Kinematic Alignment ◽  
Tibial Rotation ◽  
Medial Condyle ◽  
Maximum Extension ◽  
Posterior Tibial ◽  
Internal Tibial Rotation ◽  
Lift Off

AbstractMost medial stabilized (MS) total knee arthroplasty (TKA) implants recommend excision of the posterior cruciate ligament (PCL), which eliminates the ligament's tension effect on the tibia that drives tibial rotation and compromises passive internal tibial rotation in flexion. Whether increasing the insert thickness and reducing the posterior tibial slope corrects the loss of rotation without extension loss and undesirable anterior lift-off of the insert is unknown. In 10 fresh-frozen cadaveric knees, an MS design with a medial ball-in-socket (i.e., spherical joint) and lateral flat insert was implanted with unrestricted calipered kinematic alignment (KA) and PCL retention. Trial inserts with goniometric markings measured the internal–external orientation relative to the femoral component's medial condyle at maximum extension and 90 degrees of flexion. After PCL excision, these measurements were repeated with the same insert, a 1 mm thicker insert, and a 2- and 4-mm shim under the posterior tibial baseplate to reduce the tibial slope. Internal tibial rotation from maximum extension and 90 degrees of flexion was 15 degrees with PCL retention and 7 degrees with PCL excision (p < 0.000). With a 1 mm thicker insert, internal rotation was 8 degrees (p < 0.000), and four TKAs lost extension. With a 2 mm shim, internal rotation was 9 degrees (p = 0.001) and two TKAs lost extension. With a 4 mm shim, internal rotation was 10 degrees (p = 0.002) and five TKAs lost extension and three had anterior lift-off. The methods of inserting a 1 mm thicker insert and reducing the posterior slope did not correct the loss of internal tibial rotation after PCL excision and caused extension loss and anterior lift-off in several knees. PCL retention should be considered when using unrestricted calipered KA and implanting a medial ball-in-socket and lateral flat insert TKA design, so the progression of internal tibial rotation and coupled reduction in Q-angle throughout flexion matches the native knee, optimizing the retinacular ligaments' tension and patellofemoral tracking.

Revision of a Medial UKA to a Kinematic Aligned TKA: Comparison of Operative Complexity, Postoperative Alignment, and Outcome Scores to a Primary TKA

2019 ◽  
Author(s):  
Trevor J. Shelton ◽  
Manpreet Gill ◽  
Gurbir Athwal ◽  
Stephen M. Howell ◽  
Maury L. Hull
Keyword(s):  
Clinical Outcome ◽  
Knee Arthroplasty ◽  
Oxford Knee Score ◽  
Kinematic Alignment ◽  
Primary Group ◽  
Control Cohort ◽  
Outcome Scores ◽  
Medial Unicompartmental Knee Arthroplasty ◽  
Total Knee ◽  
Visual Analog Pain Score

AbstractRevision of a medial unicompartmental knee arthroplasty (UKA) to a mechanically aligned total knee arthroplasty (MA TKA) is inferior to a primary TKA; however, revision with kinematic alignment (KA) has not been well studied. The present study determined whether patients revised with KA had a higher use of revision components, different postoperative alignment, and different clinical outcome scores from patients with a primary KA TKA. From 2006 to 2017, all patients suitable for a revision of a failed medial UKA to a TKA and a primary TKA were treated with KA. Reasons for the revision performed in ten females and six males at a mean age 67 ± 8 years included progression of osteoarthritis in the lateral hemi-joint (n = 6), aseptic loosening (n = 4), unremitting medial pain without loosening (n = 4), and insert wear (n = 2). Patients with a revision were matched 1:3 with a control cohort treated with a primary KA TKA. Revisions were performed with primary components without augments, stem extensions, or bone grafts. Seven postoperative alignment parameters of the limb and components were comparable to the control cohort (p > 0.05). At a mean follow-up of 5 years (1–10), implant survival was 100%, and the revision/primary group clinical outcome scores were 39/43 points for the Oxford Knee Score (OKS), 2.2/1.0 cm for the Visual Analog Pain Score, and 12/7 points for the Western Ontario and McMaster Universities Osteoarthritis Index score. When compared with primary KA TKA, surgeons that revise a failed medial UKA to a TKA with use of KA can expect similar operative complexity, comparable postoperative alignments, and a mean OKS of 39 points, which is higher than the mean 27 to 30 point range reported for revision of a failed UKA to a TKA with the use of MA.

scholarly journals Kinematic Alignment in Cruciate Retaining Implants Improves the Biomechanical Function in Total Knee Arthroplasty during Gait and Deep Knee Bend

2019 ◽  
Vol 33 (03) ◽  
pp. 284-293 ◽  
Author(s):  
Kyoung-Tak Kang ◽  
Yong-Gon Koh ◽  
Ji Hoon Nam ◽  
Sae Kwang Kwon ◽  
Kwan Kyu Park
Keyword(s):  
Stance Phase ◽  
Lateral Collateral Ligament ◽  
Contact Stresses ◽  
Kinematic Alignment ◽  
Collateral Ligament ◽  
Cruciate Retaining ◽  
Lateral Contact ◽  
Lateral Collateral Ligaments ◽  
Total Knee ◽  
Maximum Contact

AbstractKinematic alignment (KA), which co-aligns the rotational axes of the components with three kinematic axes of the knee by aligning the components to the prearthritic joint lines, has been a recently introduced surgical technique. However, whether KA and cruciate retaining (CR) implants provide better biomechanical function during activities than mechanical alignment (MA) in posterior stabilized (PS) implants is unclear. We evaluated the biomechanical functions during the stance phase gait and deep knee bend, with a computer simulation and measured forces in the medial and lateral collateral ligaments and medial and lateral contact stresses in the polyethylene insert and patellar button. The forces on the medial collateral ligament in KA were lower than those in MA in both CR and PS TKA in the stance phase gait and deep knee bend conditions, whereas those on the lateral collateral ligament did not show any difference between the two surgical alignment techniques in the stance phase gait condition. The maximum contact stresses on the medial PE inserts in KA were lower than those in MA in both CR and PS TKA in the stance phase gait and deep knee bend conditions. However, the maximum contact stresses on the lateral PE inserts and the patellar button did not differ between MA and KA. The biomechanical function was superior in KA TKA than in MA TKA, and KA was more effective in CR TKA. This comparison could be used as a reference by surgeons to reduce the failure rates by using KA TKA instead of MA TKA.

scholarly journals What you need to know about kinematic alignment for total knee arthroplasty

2020 ◽  
pp. 102773
Author(s):  
Charles Rivière ◽  
Loic Villet ◽  
Dragan Jeremic ◽  
Pascal-André Vendittoli
Keyword(s):  
Total Knee Arthroplasty ◽  
Knee Arthroplasty ◽  
Kinematic Alignment ◽  
Total Knee
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