A Computer Navigation System Analysis of the Accuracy of the Extramedullary (Tibial) Alignment Technique in Total Knee Arthroplasty (TKA)

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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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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Changes in the Functional Flexion Axis of the Knee Before and After Total Knee Arthroplasty Using a Navigation System

The Journal of Arthroplasty ◽

10.1016/j.arth.2013.11.025 ◽

2014 ◽

Vol 29 (7) ◽

pp. 1388-1393 ◽

Cited By ~ 7

Author(s):

David A.J. Wilson ◽

Janie L. Astephen Wilson ◽

Glen Richardson ◽

Michael J. Dunbar

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Navigation System ◽

Before And After ◽

Total Knee

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Distal femoral cut perpendicular to the mechanical axis may induce varus instability in flexion in medial osteoarthritic knees with varus deformity in total knee arthroplasty: a pitfall of the navigation system

Journal of Orthopaedic Science ◽

10.1007/s00776-004-0818-z ◽

2004 ◽

Vol 9 (6) ◽

pp. 555-559 ◽

Cited By ~ 20

Author(s):

Ryuji Nagamine ◽

Keiichi Kondo ◽

Satoshi Ikemura ◽

Atsushi Shiranita ◽

Satoshi Nakashima ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Navigation System ◽

Mechanical Axis ◽

Varus Deformity ◽

Total Knee ◽

Varus Instability

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Benefits of Computer Navigation in Total Knee Arthroplasty

Seminars in Arthroplasty ◽

10.1053/j.sart.2011.12.003 ◽

2012 ◽

Vol 23 (1) ◽

pp. 18-23

Author(s):

Arun Mullaji ◽

Gautam M. Shetty

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Computer Navigation ◽

Total Knee

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Can a robot help a surgeon to predict a good total knee arthroplasty?

The Bone & Joint Journal ◽

10.1302/0301-620x.103b6.bjj-2020-2305.r1 ◽

2021 ◽

Vol 103-B (6 Supple A) ◽

pp. 67-73

Author(s):

Gwo-Chin Lee ◽

Edgar Wakelin ◽

Amber Randall ◽

Christopher Plaskos

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Computer Navigation ◽

Robotic System ◽

Measurement Information ◽

Robotic Assistance ◽

Ligament Balance ◽

Patient Reported ◽

Total Knee ◽

One Year

Aims Neither a surgeon’s intraoperative impression nor the parameters of computer navigation have been shown to be predictive of the outcomes following total knee arthroplasty (TKA). The aim of this study was to determine whether a surgeon, with robotic assistance, can predict the outcome as assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) for pain (KPS), one year postoperatively, and establish what factors correlate with poor KOOS scores in a well-aligned and balanced TKA. Methods A total of 134 consecutive patients who underwent TKA using a dynamic ligament tensioning robotic system with a tibia first resection technique and a cruciate sacrificing ultracongruent TKA system were enrolled into a prospective study. Each TKA was graded based on the final mediolateral ligament balance at 10° and 90° of flexion: 1) < 1 mm difference in the thickness of the tibial insert and that which was planned (n = 75); 2) < 1 mm difference (n = 26); 3) between 1 mm to 2 mm difference (n = 26); and 4) > 2 mm difference (n = 7). The mean one-year KPS score for each grade of TKA was compared and the likelihood of achieving an KPS score of > 90 was calculated. Finally, the factors associated with lower KPS despite achieving a high-grade TKA (grade A and B) were analyzed. Results Patients with a grade of A or B TKA had significantly higher mean one-year KPS scores compared with those with C or D grades (p = 0.031). There was no difference in KPS scores in grade A or B TKAs, but 33% of these patients did not have a KPS score of > 90. While there was no correlation with age, sex, preoperative deformity, and preoperative KOOS and Patient-Reported Outcomes Measurement Information System (PROMIS) physical scores, patients with a KPS score of < 90, despite a grade A or B TKA, had lower PROMIS mental health scores compared with those with KPS scores of > 90 (54.1 vs 50.8; p = 0.043). Patients with grade A and B TKAs with KPS > 90 were significantly more likely to respond with “my expectations were too low”, and with “the knee is performing better than expected” compared with patients with these grades of TKA who had a KPS score of < 90 (40% vs 22%; p = 0.004). Conclusion A TKA balanced with robotic assistance to within 1 mm of difference between the medial and lateral sides in both flexion and extension had a higher KPS score one year postoperatively. Despite accurate ligament balance information, a robotic system could not guarantee excellent pain relief. Patient expectations and mental status also significantly affected the perceived success of TKA. Cite this article: Bone Joint J 2021;103-B(6 Supple A):67–73.

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