Posterior clearance increases the knee extension angle in cruciate retaining type total knee arthroplasty: Intraoperative evaluation using a navigation system

AbstractRecently, kinematically aligned total knee arthroplasty has been found to achieve better clinical outcomes than mechanically aligned TKA. Despite the good clinical outcomes that are reported at short- to mid-term follow-up, intraoperative variables that are associated with a better outcome have not been measured. Therefore, this study was conducted to compare intraoperative kinematics/soft tissue balance and the clinical outcomes of patients who underwent modified kinematically (restricted tibial cut) or mechanically aligned total knee arthroplasty. Sixty cruciate-retaining total knee arthroplasties (30 modified kinematically [3-degree varus and 7-degree posterior slope in tibial cut] and 30 mechanically aligned) were performed in patients with varus-type osteoarthritis using a navigation system. Intraoperative kinematics assessed by the navigation system and soft tissue balance assessed by an offset-type tensor were compared between the groups. One year postoperatively, the range of motion and 2011 Knee Society scores were compared between the groups. Kinematic assessment exhibited that tibial internal rotation during flexion was significantly maintained in the kinematic compared with the mechanical group (p < 0.05). Varus/valgus ligament balance at 90 and 120 degrees of flexion significantly maintained lateral laxity in the kinematic compared with the mechanical group (p < 0.05). Improvement of flexion angles, functional activity scores, and patient satisfaction were significantly better in the kinematic than in the mechanical group (p < 0.05). Modified kinematically aligned cruciate-retaining total knee arthroplasty maintained more tibial internal rotation and lateral laxity during flexion than mechanically aligned total knee arthroplasty; thus, the former may result in better clinical outcomes.

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Tibial internal rotation is affected by lateral laxity in cruciate-retaining total knee arthroplasty: an intraoperative kinematic study using a navigation system and offset-type tensor

Knee Surgery Sports Traumatology Arthroscopy ◽

10.1007/s00167-013-2627-4 ◽

2013 ◽

Vol 22 (3) ◽

pp. 615-620 ◽

Cited By ~ 36

Author(s):

Tokio Matsuzaki ◽

Tomoyuki Matsumoto ◽

Seiji Kubo ◽

Hirotsugu Muratsu ◽

Takehiko Matsushita ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Internal Rotation ◽

Knee Arthroplasty ◽

Navigation System ◽

Cruciate Retaining ◽

Tibial Internal Rotation ◽

Kinematic Study ◽

Total Knee

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Rotational Soft-Tissue Balance Is Highly Correlated with Rotational Kinematics in Total Knee Arthroplasty

The Journal of Knee Surgery ◽

10.1055/s-0041-1729619 ◽

2021 ◽

Author(s):

Tomofumi Kinoshita ◽

Kazunori Hino ◽

Tatsuhiko Kutsuna ◽

Kunihiko Watamori ◽

Hiromasa Miura

Keyword(s):

Total Knee Arthroplasty ◽

Soft Tissue ◽

Knee Arthroplasty ◽

Navigation System ◽

Knee Kinematics ◽

Soft Tissue Balance ◽

Posterior Stabilized ◽

Cruciate Retaining ◽

Rotational Kinematics ◽

Total Knee

AbstractRecovery of normal knee kinematics is critical for improving functional outcomes and patient satisfaction after total knee arthroplasty (TKA). The kinematics pattern after TKA varies from case to case, and it remains unclear how to reproduce normal knee kinematics. The present study aimed to evaluate rotational knee kinematics and soft-tissue balance using a navigation system and to assess the influence of intraoperative soft-tissue balance on the rotational knee kinematics. We evaluated 81 osteoarthritic knees treated with TKA using a posterior stabilized (50 knees) or cruciate retaining (31 knees) prosthesis. Rotational kinematics were assessed at 0, 30, 45, 60, and 90 degrees flexion angles by using a computer-assisted navigation system. Correlation between femorotibial rotational position and measured soft tissue balance was assessed by using Spearman's rank correlation coefficient. Rotational soft-tissue balance (the median angle of rotational stress) was significantly correlated with rotational kinematics (rotational axis of the femur relative to the tibia throughout the range of motion) at all measured angles after TKA. The correlation coefficients between the median angle of rotational stress and rotational kinematics were 0.97, 0.80, 0.74, 0.71, and 0.70 at 0, 30, 45, 60, and 90 degrees of flexion, respectively (p-values <0.0001 in all measured angles). The correlation coefficient increased as the knee approached full extension. Our findings suggest that soft-tissue balance is a key factor for rotational kinematics, following both cruciate-retaining and posterior-stabilized TKA.

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The Adjustment of the Rotational Alignment of the Distal End of the Extramedullary Guide to the Anteroposterior Axis of the Proximal Tibia in Total Knee Arthroplasty

The Journal of Knee Surgery ◽

10.1055/s-0040-1722660 ◽

2021 ◽

Author(s):

Hideki Mizu-uchi ◽

Hidehiko Kido ◽

Tomonao Chikama ◽

Kenta Kamo ◽

Satoshi Kido ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Navigation System ◽

Proximal Tibia ◽

Rotational Alignment ◽

Coronal Alignment ◽

Ideal Position ◽

Total Knee ◽

Alignment Guide ◽

The Ideal

AbstractThe optimal placement within 3 degrees in coronal alignment was reportedly achieved in only 60 to 80% of patients when using an extramedullary alignment guide for the tibial side in total knee arthroplasty (TKA). This probably occurs because the extramedullary alignment guide is easily affected by the position of the ankle joint which is difficult to define by tibial torsion. Rotational direction of distal end of the extramedullary guide should be aligned to the anteroposterior (AP) axis of the proximal tibia to acquire optimal coronal alignment in the computer simulation studies; however, its efficacy has not been proven in a clinical setting. The distal end of the guide can be overly displaced from the ideal position when using a conventional guide system despite the alignment of the AP axis to the proximal tibia. This study investigated the effect of displacement of the distal end of extramedullary guide relative to the tibial coronal alignment while adjusting the rotational alignment of the distal end to the AP axis of the proximal tibia in TKA. A total of 50 TKAs performed in 50 varus osteoarthritic knees using an image-free navigation system were included in this study. The rotational alignment of the proximal side of the guide was adjusted to the AP axis of the proximal tibia. The position of the distal end of the guide was aligned to the center of the ankle joint as viewed from the proximal AP axis (ideal position) and as determined by the navigation system. The tibial intraoperative coronal alignments were recorded as the distal end was moved from the ideal position at 3-mm intervals. The intraoperative alignments were 0.5, 0.9, and 1.4 degrees in valgus alignment with 3-, 6-, and 9-mm medial displacements, respectively. The intraoperative alignments were 0.7, 1.2, and 1.7 degrees in varus alignment with 3-, 6-, and 9-mm lateral displacements, respectively. In conclusion, the acceptable tibial coronal alignment (within 2 degrees from the optimal alignment) can be achieved, although some displacement of the distal end from the ideal position can occur after the rotational alignment of the distal end of the guide is adjusted to the AP axis of the proximal tibia.

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Asymmetrical tibial polyethylene geometry-cruciate retaining total knee arthroplasty does not fully restore in-vivo articular contact kinematics during strenuous activities

Knee Surgery Sports Traumatology Arthroscopy ◽

10.1007/s00167-020-06384-9 ◽

2021 ◽

Author(s):

Christian Klemt ◽

John Drago ◽

Venkatsaiakhil Tirumala ◽

Young-Min Kwon

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Cruciate Retaining ◽

Contact Kinematics ◽

Total Knee

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Accelerometer-Based Portable Navigation System Is Useful for Tibial Bone Cutting in Modified Kinematically Aligned Total Knee Arthroplasty

The Journal of Knee Surgery ◽

10.1055/s-0039-3402481 ◽

2019 ◽

Cited By ~ 1

Author(s):

Masanori Tsubosaka ◽

Tomoyuki Kamenaga ◽

Yuichi Kuroda ◽

Koji Takayama ◽

Shingo Hashimoto ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Clinical Outcomes ◽

Knee Arthroplasty ◽

Navigation System ◽

Slope Angle ◽

Posterior Slope ◽

Tibial Bone ◽

Significant Difference ◽

Portable Navigation ◽

Total Knee

AbstractSeveral studies have reported better clinical outcomes following kinematically aligned total knee arthroplasty (KA-TKA) than mechanically aligned TKA. Consistent reproduction of a KA-TKA is aided by accurate tibial bone resections using computer navigation systems. This study compares an accelerometer-based portable navigation system with a conventional navigation system on tibial bone resection and clinical outcomes in KA-TKA. This study included 60 knees of patients who underwent primary KA-TKA between May 2015 and September 2017. They were randomly assigned to the OrthoPilot and iASSIST groups. A tibial bone cut was performed with 3 degree varus and 7 degree posterior slope in relation to the mechanical axis in all cases. The tibial component angle (TCA) and posterior slope angle (PSA) were evaluated by postoperative radiography, and those that deviated more than 2 degree were set as outliers. The clinical outcomes were the knee range of motion (ROM) and 2011 Knee Society Score (KSS) evaluated at 1 year postoperation. The groups were compared in terms of the TCA, PSA, number of outliers, ROM, and 2011 KSS (p < 0.05). No significant difference was observed between the groups in terms of the mean TCA, PSA, number of outliers, ROM, and categories of the 2011 KSS (objective knee indicators, symptoms, satisfaction, expectations, and functional activities). Although tibial bone cuts were performed with 3 degree varus and 7 degree posterior slope, no significant difference was observed between the OrthoPilot and iASSIST groups in terms of the accuracy of cuts or postoperative clinical result. The iASSIST was found to be a simple and useful navigation system for KA-TKA.

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