scholarly journals The accelerometer-based navigation system demonstrated superior radiological outcomes in restoring mechanical alignment and component sagittal positioning in total knee arthroplasty

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Jiaxiang Gao ◽  
Yunfei Hou ◽  
Rujun Li ◽  
Yan Ke ◽  
Zhichang Li ◽  
...  

Abstract Background This study aimed to determine whether the accelerometer-based navigation (ABN) could improve the accuracy of restoring mechanical axis (MA), component positioning, and clinical outcomes compared to conventional (CON) total knee arthroplasty (TKA). Methods A total of 301 consecutive patients (ABN: 27, CON: 274) were included. A 1:4 propensity score matching (PSM) was performed between the two groups according to preoperative demographic and clinical parameters. The postoperative MA, femoral coronal angle (FCA), femoral sagittal angle (FSA), tibial coronal angle (TCA) and tibial sagittal angle (TSA) were compared. Absolute deviations of aforementioned angles were calculated as the absolute value of difference between the exact and ideal value and defined as norms if within 3°, otherwise regarded as outliers. Additional clinical parameters, including the Knee Society knee and function scores (KSKS and KSFS) and range of motion (ROM), were assessed at final follow-up (FU) (mean FU was 21.88 and 21.56 months respectively for ABN and CON group). A secondary subgroup analysis and comparison on clinical outcomes were conducted between norms and outliers in different radiological parameters. Results A total of 98 patients/102 knees were analyzed after the PSM (ABN: 21 patients/24 knees, CON: 77 patients/78 knees). In the ABN group, the mean MA, FCA and TSA were significantly improved (p = 0.019, 0.006, < 0.001, respectively). Proportions of TKAs within a ± 3°deviation were significantly improved in all the postoperative radiological variables except for TCA (p = 0.003, 0.021, 0.042, 0.013, respectively for MA, FCA, FSA, and TSA). The absolute deviations of FSA and TSA were also significantly lower in the ABN group (p = 0.020, 0.048, respectively). No significant differences were found in either mean value, absolute deviation or outlier ratio of TCA between two groups. On clinical outcomes, there were no significant differences between two groups, although KSKS, KSFS and ROM (p < 0.01, respectively) dramatically improved compared to baseline. The subgroup analysis also demonstrated no statistical difference on clinical outcomes between the outliers and norms in varied radiological parameters. Conclusions The ABN could improve the accuracy and precision of mechanical alignment and component positioning without significant improvement of clinical outcomes. Further high quality studies with long term FU are warranted to comprehensively evaluate the value of the ABN.

2020 ◽  
Author(s):  
Jiaxiang Gao ◽  
Yunfei Hou ◽  
Zhichang Li ◽  
Runjun Li ◽  
Yan Ke ◽  
...  

Abstract Background: This study aimed to determine whether the iAssist navigation system (NAV) could improve the accuracy of restoring mechanical axis (MA), component positioning, and clinical outcomes compared to conventional (CON) total knee arthroplasty (TKA). Methods: A total of 301 consecutive patients (NAV: 27, CON: 274) were included. A 1:4 propensity score matching (PSM) was performed between the two groups according to preoperative demographic and clinical parameters. The postoperative MA, femoral coronal angle (FCA), femoral sagittal angle (FSA), tibial coronal angle (TCA) and tibial sagittal angle (TSA) were compared. Absolute deviations of aforementioned angles were calculated as the absolute value of difference between the exact and ideal value and defined as appropriate if within 3°, otherwise regarded as outliers. Additional clinical parameters, including the Knee Society knee and function scores (KSKS and KSFS) and range of motion (ROM), were assessed at the final follow-up (mean follow-up time was 21.88 and 21.56 months respectively for NAV and CON group). Results: A total of 98 patients/102 knees were analyzed after the PSM (NAV: 21 patients/24 knees, CON: 77 patients/78 knees). In the NAV group, the mean MA, FCA and TSA were significantly improved (p = 0.019, 0.006, <0.001, respectively). Proportions of TKAs within a ±3°deviation were significantly improved in all the postoperative radiological variables except for TCA (p = 0.003, 0.021, 0,017, 0.013, respectively for MA, FCA, FSA, and TSA). The absolute deviations of FSA and TSA were also significantly lower in the NAV group (p = 0.016, 0.048, respectively). In particular, no significant differences were found in either mean value, absolute deviation or outlier ratio of TCA between two groups. For the clinical outcomes, there were no significant differences between two groups, although KSKS, KSFS and ROM (p<0.01, respectively) dramatically improved compared to baseline. Conclusions: We suggested that the iAssist system could improve the accuracy and precision of mechanical alignment and component positioning without significant improvement of clinical outcomes. Further long-term high-quality studies are necessary to validate the results.


2016 ◽  
Vol 10 (1) ◽  
pp. 357-363 ◽  
Author(s):  
Panagiota Toliopoulos ◽  
Marc-Andre LeBlanc ◽  
Jonathan Hutt ◽  
Martin Lavigne ◽  
Francois Desmeules ◽  
...  

Objectives:The purpose of this study was to compare the intra-operative benefits and the clinical outcomes from kinematic or mechanical alignment for total knee arthroplasty (TKA) in patients undergoing revision of failed unicompartmental kneel arthroplasty (UKA) to TKA.Methods:Ten revisions were performed with a kinematic alignment technique and 11 with a mechanical alignment. Measurements of the hip-knee-ankle angle (HKA), the lateral distal femoral angle (LDFA), and the medial proximal tibial angle (MPTA) were performed using long-leg radiographs. The need for augments, stems, and constrained inserts was compared between groups. Clinical outcomes were compared using the WOMAC score along with maximum distance walked as well as knee range of motion obtained prior to discharge. All data was obtained by a retrospective review of patient files.Results:The kinematic group required less augments, stems, and constrained inserts than the mechanical group and thinner polyethylene bearings. There were significant differences in the lateral distal femoral angle (LDFA) and the medial proximal tibial angle (MPTA) between the two groups (p<0.05). The mean WOMAC score obtained at discharge was better in the kinematic group as was mean knee flexion. At last follow up of 34 months for the kinematic group and 58 months for the mechanical group, no orthopedic complications or reoperations were recorded.Conclusion:Although this study has a small patient cohort, our results suggest that kinematic alignment for TKA after UKA revision is an attractive method. Further studies are warranted.


2020 ◽  
Vol 72 ◽  
pp. 63-68
Author(s):  
Andrea Giorgini ◽  
Francesco Zambianchi ◽  
Martina Lombardi ◽  
Elena Francioni ◽  
Andrea Marcovigi ◽  
...  

2020 ◽  
Vol 5 (8) ◽  
pp. 486-497
Author(s):  
Mark Anthony Roussot ◽  
Georges Frederic Vles ◽  
Sam Oussedik

Although mechanical alignment (MA) has traditionally been considered the gold standard, the optimal alignment strategy for total knee arthroplasty (TKA) is still debated. Kinematic alignment (KA) aims to restore native alignment by respecting the three axes of rotation of the knee and thereby producing knee motion more akin to the native knee. Designer surgeon case series and case control studies have demonstrated excellent subjective and objective clinical outcomes as well as survivorship for KA TKA with up to 10 years follow up, but these results have not been reproduced in high-quality randomized clinical trials. Gait analyses have demonstrated differences in parameters such as knee adduction, extension and external rotation moments, the relevance of which needs further evaluation. Objective improvements in soft tissue balance using KA have not been shown to result in improvements in patient-reported outcomes measures. Technologies that permit accurate reproduction of implant positioning and objective measurement of soft tissue balance, such as robotic-assisted TKA and compartmental pressure sensors, may play an important role in improving our understanding of the optimum alignment strategy and implant position. Cite this article: EFORT Open Rev 2020;5:486-497. DOI: 10.1302/2058-5241.5.190093


Author(s):  
Jung-Won Lim ◽  
Yong-Beom Park ◽  
Dong-Hoon Lee ◽  
Han-Jun Lee

AbstractThis study aimed to evaluate whether manipulation under anesthesia (MUA) affect clinical outcome including range of motion (ROM) and patient satisfaction after total knee arthroplasty (TKA). It is hypothesized that MUA improves clinical outcomes and patient satisfaction after primary TKA. This retrospective study analyzed 97 patients who underwent staged bilateral primary TKA. MUA of knee flexion more than 120 degrees was performed a week after index surgery just before operation of the opposite site. The first knees with MUA were classified as the MUA group and the second knees without MUA as the control group. ROM, Knee Society Knee Score, Knee Society Functional Score, Western Ontario and McMaster Universities (WOMAC) score, and patient satisfaction were assessed. Postoperative flexion was significantly greater in the MUA group during 6 months follow-up (6 weeks: 111.6 vs. 99.8 degrees, p < 0.001; 3 months: 115.9 vs. 110.2 degrees, p = 0.001; 6 months: 120.2 vs. 117.0 degrees, p = 0.019). Clinical outcomes also showed similar results with knee flexion during 2 years follow-up. Patient satisfaction was significantly high in the MUA group during 12 months (3 months: 80.2 vs. 71.5, p < 0.001; 6 months: 85.8 vs. 79.8, p < 0.001; 12 months: 86.1 vs. 83.9, p < 0.001; 24 months: 86.6 vs. 85.5, p = 0.013). MUA yielded improvement of clinical outcomes including ROM, and patient satisfaction, especially in the early period after TKA. MUA in the first knee could be taken into account to obtain early recovery and to improve patient satisfaction in staged bilateral TKA.


Author(s):  
Nicola Pizza ◽  
Stefano Di Paolo ◽  
Raffaele Zinno ◽  
Giulio Maria Marcheggiani Muccioli ◽  
Piero Agostinone ◽  
...  

Abstract Purpose To investigate if postoperative clinical outcomes correlate with specific kinematic patterns after total knee arthroplasty (TKA) surgery. The hypothesis was that the group of patients with higher clinical outcomes would have shown postoperative medial pivot kinematics, while the group of patients with lower clinical outcomes would have not. Methods 52 patients undergoing TKA surgery were prospectively evaluated at least a year of follow-up (13.5 ± 6.8 months) through clinical and functional Knee Society Score (KSS), and kinematically through dynamic radiostereometric analysis (RSA) during a sit-to-stand motor task. Patients received posterior-stabilized TKA design. Based on the result of the KSS, patients were divided into two groups: “KSS > 70 group”, patients with a good-to-excellent score (93.1 ± 6.8 points, n = 44); “KSS < 70 group”, patients with a fair-to-poor score (53.3 ± 18.3 points, n = 8). The anteroposterior (AP) low point (lowest femorotibial contact points) translation of medial and lateral femoral compartments was compared through Student’s t test (p < 0.05). Results Low point AP translation of the medial compartment was significantly lower (p < 0.05) than the lateral one in both the KSS > 70 (6.1 mm ± 4.4 mm vs 10.7 mm ± 4.6 mm) and the KSS < 70 groups (2.7 mm ± 3.5 mm vs 11.0 mm ± 5.6 mm). Furthermore, the AP translation of the lateral femoral compartment was not significantly different (p > 0.05) between the two groups, while the AP translation of the medial femoral compartment was significantly higher for the KSS > 70 group (p = 0.0442). Conclusion In the group of patients with a postoperative KSS < 70, the medial compartment translation was almost one-fourth of the lateral one. Surgeons should be aware that an over-constrained kinematic of the medial compartment might lead to lower clinical outcomes. Level of evidence II.


Author(s):  
Pablo Besa ◽  
Rafael Vega ◽  
Gerardo Ledermann ◽  
Claudio Calvo ◽  
Manuela Angulo ◽  
...  

AbstractThis study aimed to determine the tibial cut (TC) accuracy using extensor hallucis longus (EHL) tendon as an anatomical landmark to position the total knee arthroplasty (TKA) extramedullary tibial guide (EMTG), and its impact on the TKA mechanical alignment (MA). We retrospectively studied 96 TKA, performed by a single surgeon, using a femoral tailored intramedullary guide technique. Seventeen were prior to the use of the EHL and 79 used the EHL tendon to position the EMTG. We analyzed preoperative and postoperative standing total lower extremity radiographs to determine the tibial component angle (TCA) and the correction in MA, comparing pre-EHL use and post-EHL technique incorporation. Mean TCA was 88.89 degrees and postoperative MA was neutral in 81% of patients. Pre- and postoperative MAs were not correlated. As a conclusion of this study, using the EHL provides a safe and easy way to determine the position of EMTG.


Author(s):  
Omer Ayik ◽  
Mehmet Demirel ◽  
Fevzi Birisik ◽  
Ali Ersen ◽  
Halil I. Balci ◽  
...  

AbstractThe present randomized controlled study aims to evaluate whether tourniquet application during total knee arthroplasty (TKA) has an effect on (1) thigh muscle strength (quadriceps and hamstring muscle strength) and (2) clinical outcomes (postoperative knee range of motion [ROM], postoperative pain level, and Knee Society Score [KSS]). The effects of tourniquet application during TKA were investigated in 65 patients randomly allocated to one of two groups: TKA with a tourniquet and TKA without a tourniquet. Patients in both groups were comparable in terms of the demographic and clinical data (p > 0.05 for age, number of patients, sex, radiographic gonarthrosis grade, American Society of Anesthesiologists [ASA] classification, and body mass index [BMI]). All patients in both groups were operated by the same surgeon using one type of prosthesis. Isokinetic muscle strength (peak torque and total work) of knee extensors (quadriceps) and flexors (hamstrings) was measured in Newton meters (Nm) using a CYBEX 350 isokinetic dynamometer (HUMAC/CYBEX 2009, Stoughton, MA). The combined KSS (knee score + function score), visual analog scale (VAS), and knee ROM were measured preoperatively and at 1 and 3 months postoperatively to evaluate clinical outcomes. There were no significant differences between the two groups in preoperative and postoperative values of isokinetic muscle strength (peak torque and total work) and aforementioned clinical outcomes (p < 0.05). The present study has shown that quadriceps strength and clinical outcomes were not improved in the early postoperative period (3 months) when a tourniquet was not used during TKA.


Author(s):  
Masanori Tsubosaka ◽  
Tomoyuki Kamenaga ◽  
Yuichi Kuroda ◽  
Koji Takayama ◽  
Shingo Hashimoto ◽  
...  

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.


2015 ◽  
Vol 2015 ◽  
pp. 1-3 ◽  
Author(s):  
Dongquan Shi ◽  
Xingquan Xu ◽  
Anyun Guo ◽  
Jin Dai ◽  
Zhihong Xu ◽  
...  

Introduction. Mechanical alignment deviation after total knee arthroplasty is a major reason for early loosening of the prosthesis. Achieving optimum cement penetration during fixation of the femoral and tibial component is an essential step in performing a successful total knee arthroplasty. Bone cement is used to solidify the bone and prosthesis. Thickness imbalance of bone cement leads to the deviation of mechanical alignment. To estimate the influence of bone cement, a retrospective study was conducted.Materials and Methods. A total of 36 subjects were studied. All the TKA were performed following the standard surgical protocol for navigated surgery by medial approach with general anaesthesia. Prostheses were fixed by bone cement.Results. We compared the mechanical axis, flexion/extension, and gap balance before and after cementation. All the factors were different compared with those before and after cementation. Internal rotation was reached with statistical significance (P=0.03).Conclusion. Bone cement can influence the mechanical axis, flexion/extension, and gap balance. It also can prompt us to make a change when poor knee kinematics were detected before cementation.


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