Navigated versus Conventional Technique in High Tibial Osteotomy: A Meta-Analysis Focusing on Weight Bearing Effect.
ABSTRACT: Purpose:We aimed to determine whether navigated opening wedge high tibial osteotomy (HTO) is superior to the conventional technique in terms of accuracy of the coronal and sagittal alignment correction, functional outcome, and operative time. Methods:Studies comparing navigated and conventional HTO were included in this meta-analysis. We compared the incidence of radiological outliers in coronal alignment and tibial slope maintenance, mean differences in functional outcome scales, and operative time. Subgroup analyses were performed on coronal alignment accuracy based on the intraoperative method of alignment confirmation: fluoroscopy vs. gap measurement method. Results:Twelve studies were included: there were 434 knees in the navigated HTO studies and 405 knees in the conventional HTO studies. The risk of outlier was lower in navigated HTO than in conventional HTO; however, the difference was not significant when navigated HTO was compared with conventional HTO performed using the gap measurement method. Tibial slope maintenance was comparable or better in navigated HTO. No difference was found in the American Knee Society function and Lysholm scores. Navigated HTO necessitated a longer operative time of approximately 10 minutes. Conclusions:The use of navigation in HTO can improve accuracy in both coronal and sagittal alignments, but its clinical benefit is unclear.
Project description:Background:The use of navigation for total knee arthroplasty (TKA) improves limb alignment in the coronal and sagittal planes. However, similar improvements in femoral and tibial component rotation have not yet been realized using currently available systems. Methods:We developed a modified navigated TKA technique in which femoral rotation was set using the resected tibial plane as the reference with the aim of achieving a rectangular flexion gap. Limb alignment was assessed in a cohort of 30 knees using the navigation system. Post-operative limb alignment was measured using long-leg standing radiographs. Computed tomography was used to determine post-operative component orientation. Results:Sagittal alignment data improved from a mean of 7.8° varus (pre-operative) to 0.0° (post-operative), assessed by intra-operative navigation. Post-operative hip-knee-ankle axis alignment was 0.9° valgus (mean; standard deviation [SD] 1.7°). Mean femoral component rotation was 0.5° internally rotated (SD 2.6°), relative to the surgical transepicondylar axis. Mean tibial component rotation was 0.9° externally rotated (SD 5.5°). No soft tissue releases were performed. Conclusions:These results confirm that the desired femoral rotation, set using a tibia-first approach with the resected tibial plane as the reference, can be achieved without compromising overall limb alignment. Femoral component rotation was within a narrow range, with a moderate improvement in achieving more consistent tibial component rotation compared with other techniques. This technique may prove to be useful for surgeons wishing to employ a tibia-first philosophy for TKA while maximizing the benefits associated with computer-assisted navigation.
Project description:PURPOSE:Patient-specific instrumentation (PSI) has been proposed as a means of improving surgical accuracy and ease of implantation during technically challenging procedures such as unicompartmental knee arthroplasty (UKA). The purpose of this prospective randomised controlled trial was to compare the accuracy of implantation and functional outcome of mobile-bearing medial UKAs implanted with and without PSI by experienced UKA surgeons. METHODS:Mobile-bearing medial UKAs were implanted in 43 patients using either PSI guides or conventional instrumentation. Intra-operative measurements, meniscal bearing size implanted, and post-operative radiographic analyses were performed to assess component positioning. Functional outcome was determined using the Oxford Knee Score (OKS). RESULTS:PSI guides could not be used in three cases due to concerns regarding accuracy and registration onto native anatomy, particularly on the tibial side. In general, similar component alignment and positioning was achieved using the two systems (n.s. for coronal/sagittal alignment and tibial coverage). The PSI group had greater tibial slope (p = 0.029). The control group had a higher number of optimum size meniscal bearing inserted (95 vs 52%; p = 0.001). There were no differences in OKS improvements (n.s). CONCLUSION:Component positioning for the two groups was similar for the femur but less accurate on the tibial side using PSI, often with some unnecessarily deep resections of the tibial plateau. Although PSI was comparable to conventional instrumentation based on OKS improvements at 12 months, we continue to use conventional instrumentation for UKA at our institution until further improvements to the PSI guides can be demonstrated. LEVEL OF EVIDENCE:Therapeutic, Level I.
Project description:<h4>Purpose</h4>A multiaxial correction (MAC) fixator is a monolateral type of fixator that can correct multi-planer deformities. The purpose of this study is to compare the clinical outcome of correction for tibial deformities with the MAC fixator and the circular external fixators.<h4>Methods</h4>We retrospectively reviewed consecutive patients reconstructed with the MAC fixator (MAC group) or circular external fixators (Ring group) due to the congenital diseases or residual conditions after treatment of trauma, infection, tumor, or limb lengthening between 2003 and 2016.<h4>Results</h4>The 30 patients who had angular tibial deformity were included. In patients with tibia vara or lateral bowing, the average pre-operative mechanical medial proximal tibial angle (mMPTA) of the MAC group and the Ring group was significantly increased to 86.9 ± 3.5° in the MAC group and 88.0 ± 3.6° in the Ring group postoperatively. Medial bowing was also successfully corrected in both groups. Regarding the sagittal alignment, post-operative anatomical posterior proximal tibial angle (aPPTA) of the MAC group was deteriorated after coronal correction. The operative time was significantly shorter in the MAC group than the Ring group (p < 0.05).<h4>Conclusion</h4>The MAC fixator successfully corrected coronal deformities of the tibia with shorter operative time, but it has a risk of occurrence of the procurvatum deformity compared with circular external fixators. Paying attention to the sagittal alignment, the MAC fixator can be one of the treatment options for correction of the coronal tibial deformities.
Project description:<h4>Purpose</h4>Favorable clinical results have been reported following high tibial osteotomy (HTO) for medial meniscus posterior root tear (MMPRT) in knees with varus alignment. However, the effect on the preoperative neutral alignment of the knee is not known. This study sought to evaluate the clinical outcomes of medial open-wedge HTO for MMPRT with neutral alignment.<h4>Methods</h4>We retrospectively reviewed 119 medial open-wedge HTOs and analyzed 22 knees with MMPRT. The knees were divided according to the preoperative hip-knee-ankle angle into a moderate varus alignment group (≤4° of varus alignment) and a varus alignment group (> 4° of varus alignment). The Knee Injury and Osteoarthritis Outcome Score (KOOS) and Forgotten Joint Score-12 (FJS-12) values were evaluated preoperatively and at the latest follow-up. The healing status of MMPRT at the time of second-look arthroscopy, performed at a mean of 15.4 ± 4.2 months, was compared with that after the primary HTO.<h4>Results</h4>There were 11 knees in the moderate varus alignment group and 11 in the varus alignment group. In terms of perioperative patient-reported outcome measures, there was no significant difference in the preoperative or postoperative KOOS subscale score or FJS-12 score between the moderate varus and varus alignment groups. The healing rate was significantly higher in the moderate varus alignment group.<h4>Conclusion</h4>Favorable clinical results were obtained by medial open-wedge HTO in knees with MMPRT and moderate varus alignment in the short term. Surgeons should consider the indications for medial open-wedge HTO, even with moderate varus alignment, when planning treatment for MMPRT with persistent knee pain.<h4>Level of evidence</h4>IV.
Project description:<h4>Aim</h4>The objective of the study is to compare the accuracy of implant positioning and limb alignment achieved in robotic-arm assisted total knee arthroplasty(RATKA) and manual total knee arthroplasty(MTKA) to their respective preoperative plan.<h4>Patients and methods</h4>This was a prospective observational study conducted in a tertiary care centre between August 2018 and January 2020. 143 consecutive RATKA(105 patients) and 151 consecutive MTKA(111 patients) performed by two experienced arthroplasty surgeons were included. Two independent observers evaluated the accuracy of implant positioning by measuring the radiological parameters according to the Knee-Society-Roentgenographic-Evaluation-System and limb alignment from postoperative weight-bearing scanogram. Outcomes were defined, based on the degree of deviation of measurements from the planned position and alignment, as excellent(0-1.99°), acceptable(2.00-2.99°) and outlier(≥ 3.00°).<h4>Results</h4>There were no systematic differences in the demographic and baseline characteristics between RATKA and MTKA. Statistically significant outcomes were observed favouring robotic group for postoperative mechanical axis (<i>p</i> < .001), coronal inclination of the femoral component (<i>p</i> < 0.001), coronal inclination of tibial component (<i>p</i> < 0.001), and sagittal inclination of tibial component (<i>p</i> < 0.001). There was no significant difference in the sagittal inclination of the femoral component (<i>p</i> = 0.566). The percentage of knees in the 'excellent' group were higher in RATKA compared to MTKA. There was absolutely no outlier in terms of limb alignment in the RATKA group versus 23.8% (<i>p</i> < 0.001) in the MTKA group. All the measurements showed high interobserver and intraobserver reliability.<h4>Conclusion</h4>Robotic-arm assisted TKA executed the preoperative plan more accurately with respect to limb alignment and implant positioning compared to manual TKA, even when the surgeons were more experienced in the latter.<h4>Graphic abstract</h4><h4>Supplementary information</h4>The online version contains supplementary material available at 10.1007/s43465-020-00324-y.
Project description:It has been reported that an accelerometer-based portable navigation device can achieve accurate bone cuts, but there have been few studies of clinical outcomes after total knee arthroplasty (TKA) using such a device. The aim of this study was to evaluate lower limb alignment and clinical outcomes after TKA using an accelerometer-based portable navigation device. Thirty-five patients (40 knees) underwent primary TKAs using an accelerometer-based portable navigation device. Postoperative radiographic assessments included the hip-knee-ankle angle, femoral component angle (FCA), and tibial component angle (TCA) in the coronal plane and the sagittal FCA and sagittal TCA in the sagittal plane. Clinical outcomes were evaluated by the Japanese Orthopedic Association score for osteoarthritic knees, Japanese Knee Osteoarthritis Measure, and the New Knee Society Score. The frequency of outliers (>3 degrees) was 10% for the hip-knee-ankle angle, 8% for FCA, 0% for TCA, 19% for sagittal FCA, and 9% for sagittal TCA. The Japanese Orthopedic Association score and Japanese Knee Osteoarthritis Measure were significantly improved postoperatively. The postoperative New Knee Society Score was 67.2% for symptoms, 50.3% for satisfaction, 58.6% for expectation, and 44.1% for function. TKA using an accelerometer-based portable navigation device achieved good results for both lower limb alignment and clinical outcomes.
Project description:BACKGROUND:The mobile Oxford unicompartmental knee arthroplasty (UKA) implant has been widely used with an intramedullary guide for femoral preparation. We modified the femoral guide technique based on the tibial cut first and spacer block technique. This study was performed to determine the radiographic accuracy and early clinical outcomes of the extramedullary method. METHODS:We retrospectively evaluated 50 consecutive patients who underwent UKA using the extramedullary technique. An equal number of patients who underwent UKA with the conventional technique were matched as the control group. Clinical outcomes were evaluated in terms of the operating time, blood loss, range of motion, and Hospital for Special Surgery score. Radiographic accuracy was evaluated by the implant position and alignment in the coronal and sagittal planes. RESULTS:The mean follow-up period was 39.76 ± 5.77?months. There were no differences in the postoperative Hospital for Special Surgery score, range of motion, or hip-knee-ankle angle between the two groups. The operating time in the extramedullary group was shorter than that in the conventional group (54.78 ± 7.95 vs. 59.14 ± 10.91?min, respectively; p = 0.025). The drop in hemoglobin after 3?days was only 12.34 ± 4.98?g/L in the extramedullary group which was less than that in the conventional group (p = 0.001). No significant differences were found in the postoperative coronal and sagittal angles between the two groups. Acceptable radiographic accuracy of the implant alignment and position was achieved in 92% of patients in the extramedullary group and 96% of patients in the conventional group. CONCLUSIONS:The radiographic and clinical results of the extramedullary technique were comparable with those of the conventional technique with the advantage of no intramedullary interruption, less blood loss, a shorter operating time, and more rapid recovery. As the technique depends on the accurate tibial cut and overall alignment, we do not recommend it to surgeons without high volume experiences. TRIAL REGISTRATION:Retrospectively registered LEVEL OF EVIDENCE: IV, retrospective study.
Project description:For opening wedge high tibial osteotomy (OWHTO), it is recommended that the osteotomy line is parallel to the medial tibial posterior slope (TPS) in the sagittal view and that the alignments are simultaneously controlled in the coronal and sagittal views. Here combined computed tomography (CT)-based and image-free navigation systems were used for intraoperative reference during OWHTO. Using the CT-based navigation, 2 entry points for insertion of Kirschner wires were preoperatively set up and an accurate osteotomy plane was intraoperatively duplicated. Preoperative planning anticipated a femorotibial angle of 170°, representing a weight-bearing ratio of 62.5%, on the whole-leg radiograph. The original TPS in the sagittal view was aimed to be preserved postoperatively. The hip-knee-ankle (HKA) correction angle was preoperatively measured on the whole-leg radiograph, and the HKA angle and flexion angle were intraoperatively monitored in real time using the image-free navigation. We have introduced an operative technique for OWHTO using CT-based and image-free navigation systems. We expect that this method, with the osteotomy plane parallel to the tibial plateau plane in the sagittal view and simultaneous control of coronal and sagittal alignments, will enable actuation of accurate alignment in the 2 planes and lead to improvements in patient activity in future.
Project description:BACKGROUND:Previously, the authors modified the surgical technique to preserve tibial bone mass for Oxford unicompartmental knee arthroplasty (UKA). The purpose of this study was to determine the clinical outcomes and values of this modified technique. METHODS:Clinical data of 34 consecutive patients who underwent the unilateral modified UKA technique (modified group, 34 knees) were retrospectively analyzed. To compare the outcome, a match-paired control group (conventional group, 34 knees) of an equal number of patients using the conventional technique system in the same period were selected and matched with respect to diagnosis, age, pre-operative range of motion (ROM), and radiological grade of knee arthrosis. Clinical outcomes including knee Hospital for Special Surgery (HSS) score, ROM, and complications were compared between the two groups. Post-operative radiographic assessments included hip-knee-ankle angle (HKA), joint line change, implant position, and alignment. RESULTS:The mean follow-up time was 38.2?±?6.3 months. There was no difference in baseline between the two groups. The amount of proximal tibial bone cut in the modified group was significantly less than that of the conventional group (4.7?±?1.1?mm vs. 6.7?±?1.3?mm, t?=?6.45, P?<?0.001). Joint line was elevated by 2.1?±?1.0?mm in the modified group compared with -0.5?±?1.7?mm in the conventional group (t?=?-7.46, P?<?0.001). No significant differences were observed between the two groups after UKA with respect to HSS score, VAS score, ROM, and HKA. Additionally, the accuracy of the post-operative implant position and alignment was similar in both groups. As for implant size, the tibial implant size in the modified group was larger than that in the conventional group (??=?4.95, P?=?0.035). CONCLUSIONS:The modified technique for tibial bone sparing was comparable with the conventional technique in terms of clinical outcomes and radiographic assessments. It can preserve tibial bone mass and achieve a larger cement surface on the tibial side.
Project description:<h4>Background</h4>The controversy regarding the outcome of total knee arthroplasties after high tibial osteotomy may relate to malalignment secondary to overcorrection after high tibial osteotomy (HTO) [1, 2] and to the type of arthroplasty itself (posterior-stabilized arthroplasty or posterior cruciate ligament-retaining prosthesis).<h4>Questions/purpose</h4>We asked two questions: (1) Would a posterior-stabilized arthroplasty provide sufficient constrain and improve pain and function in patients with severe malalignment due to a previous HTO? (2) Will malalignment of the previous HTO jeopardize the long-term results of a total knee reconstruction with a posterior-stabilized implant?<h4>Patients and methods</h4>We retrospectively reviewed 25 posterior-stabilized TKAs in 25 patients with severe valgus deformity after HTO (ranging from 10° to 20° of valgus) and compared the results with a series of matched 25 posterior-stabilized TKAs in 25 patients with normocorrection after HTO ranging from 5° of valgus to 5° of varus. Clinical, operative, and radiographic data were reviewed. Minimum follow-up was 10 years after the arthroplasty (average, 15 years; range, 10-20 years).<h4>Results</h4>All the knees had standard posterior-stabilized total knee arthroplasty implants. Patients with an overcorrected HTO were more likely to require a soft tissue release to balance the knee. However, Average Knee Society and Function Score improved, respectively, from 48 to 85 and from 50 to 90 points in the severely overcorrected group, versus, respectively, 50 to 89 and 52 to 97 in the normocorrected group, but the range of mobility was superior for patients with normal alignment. Fifteen-year survivorship after the arthroplasty comparison showed no significant difference between the two groups (one revision in each group).<h4>Conclusions</h4>Patients with an overcorrected HTO are more likely to require a soft tissue release to balance the knee. However, both groups show improvements in function and pain. With a posterior-stabilized arthroplasty, the degree of deformity has no impact on the longevity of the TKA.