Journal of Joint Surgery and Research最新文献

{"title":"Porous tantalum versus titanium-coated acetabular cups in total hip arthroplasty: Midterm radiological evidence of supralateral bone defect filling without grafting","authors":"Takuhei Kozaki ,&nbsp;Satoru Yamazaki ,&nbsp;Kimihide Murakami ,&nbsp;Shigeki Sando ,&nbsp;Koji Hashimoto ,&nbsp;Akihiro Hoshino ,&nbsp;Yuki Kuboi ,&nbsp;Daisuke Nishiyama ,&nbsp;Daisuke Fukui ,&nbsp;Mamoru Kawakami","doi":"10.1016/j.jjoisr.2025.06.002","DOIUrl":"10.1016/j.jjoisr.2025.06.002","url":null,"abstract":"<div><h3>Purpose</h3><div>Like bone formation, porous tantalum (Ta) for total hip arthroplasty (THA) improves both initial stability and secondary biological fixation compared with porous titanium (Ti). The authors have occasionally observed new bone formation filling the cavity between the acetabular cup and acetabular bone in the supralateral part over time. This study aimed to investigate whether an improvement in bone coverage of the Ta cup was observed over time compared with that of the Ti cup.</div></div><div><h3>Methods</h3><div>This study included 223 patients (223 hips) with hip osteoarthritis who underwent primary THA using either a Ta or Ti cup. Host bone coverage of the acetabular cup was examined on radiographs using the cup center-edge (CE) angle and bone coverage index (BCI). Radiologically measured cup inclination (RI) was also measured.</div></div><div><h3>Results</h3><div>At 5 years, the mean cup CE angle was 35.3 ​± ​7.5° for Ti and 37.4 ​± ​7.1° for TA (<em>p</em> ​= ​0.036), and the BCI was 90.8 ​± ​5.4% and 92.6 ​± ​6.6, respectively (<em>p</em> ​= ​0.033). The improvement rates from 2 years to 5 years and from baseline to 5 years were statistically significantly greater in the Ta group than in the Ti group. In the multiple regression analysis, BCI at baseline (<em>p</em> ​&lt; ​0.0001), Ta (<em>p</em> ​= ​0.018), and RI (<em>p</em> ​= ​0.018) were significant predictors of BCI improvement 2–5 years later.</div></div><div><h3>Conclusions</h3><div>Filling the bone deficit in the lateral part of the cup without a bone graft over time had an advantage in the Ta cup over the Ti cup, which may enhance long-term survival. Additionally, RI and BCI were identified as important factors.</div></div>","PeriodicalId":100795,"journal":{"name":"Journal of Joint Surgery and Research","volume":"3 3","pages":"Pages 138-144"},"PeriodicalIF":0.0,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144596657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tranexamic acid in total hip arthroplasty: Nationwide evidence for reducing blood transfusions and post-operative complications","authors":"Hidetatsu Tanaka ,&nbsp;Kunio Tarasawa ,&nbsp;Yu Mori ,&nbsp;Kazuyoshi Baba ,&nbsp;Ryuichi Kanabuchi ,&nbsp;Yasuaki Kuriyama ,&nbsp;Hiroaki Kurishima ,&nbsp;Hideki Fukuchi ,&nbsp;Hiroki Kawamata ,&nbsp;Kiyohide Fushimi ,&nbsp;Toshimi Aizawa ,&nbsp;Kenji Fujimori","doi":"10.1016/j.jjoisr.2025.06.004","DOIUrl":"10.1016/j.jjoisr.2025.06.004","url":null,"abstract":"<div><h3>Purpose</h3><div>Total hip arthroplasty (THA) is an effective treatment for hip degenerative diseases; however, peri-operative blood loss often necessitates blood transfusion. Tranexamic acid (TXA) is widely used to reduce bleeding, although limited real-world evidence exists from Japanese populations. This study assessed the association between peri-operative TXA use and transfusion requirements and complications using nationwide data.</div></div><div><h3>Methods</h3><div>THA cases in the Japanese Diagnosis Procedure Combination (DPC) database from December 2011 to March 2023 were retrospectively analyzed. Patients undergoing primary THA for osteoarthritis, osteonecrosis, or rheumatoid arthritis were included. One-to-one propensity score (PS) matching was performed between patients who received TXA and those who did not. Logistic regression was used to evaluate outcomes including allogenic and autologous transfusion rate, infection, deep vein thrombosis (DVT), pulmonary embolism (PE), and death. A subgroup analysis of TXA dosage (≥2000 ​mg <em>vs.</em> &lt;2000 ​mg) was performed.</div></div><div><h3>Results</h3><div>After PS matching, 134,653 patients were included in each group. TXA use significantly reduced allogeneic transfusion on post-operative Day 0 [odds ratio (OR) 0478], Day 1 (OR 0.377), and Day 2 (OR 0.339). Similarly, TXA use significantly reduced autologous transfusion rates on Day 0 (OR 0.555), Day 1 (OR 0.486), and Day 2 (OR 0.533). Higher TXA doses (≥2000 ​mg) further reduced Day 0 allogeneic and autologous transfusions, but increased autologous transfusion risk on Day 1. While no statistically significant differences were found in infection, PE, or death, TXA was associated with a slightly higher DVT risk.</div></div><div><h3>Conclusions</h3><div>Peri-operative TXA use in THA reduced transfusion needs without increasing PE or mortality risks, although careful monitoring for DVT is warranted. Future studies should clarify optimal dosing strategies tailored to Japanese populations.</div></div>","PeriodicalId":100795,"journal":{"name":"Journal of Joint Surgery and Research","volume":"3 3","pages":"Pages 132-137"},"PeriodicalIF":0.0,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is selective hospitalist–orthopedic surgeon co-management based on the Charlson comorbidity index useful in peri-operative care of total hip arthroplasty?","authors":"Kazuhiko Sonoda ,&nbsp;Yusuke Kubo ,&nbsp;Sanshiro Inoue ,&nbsp;Toshihiko Hara","doi":"10.1016/j.jjoisr.2025.06.003","DOIUrl":"10.1016/j.jjoisr.2025.06.003","url":null,"abstract":"<div><h3>Purpose</h3><div>Total hip arthroplasty (THA) is an effective treatment for hip diseases, but peri-operative management of patients with multiple comorbidities is challenging due to an increased risk of medical complications. Hospitalist–orthopedic surgeon co-management (HOC) has been reported to improve peri-operative care, but its effectiveness and impact on healthcare resources remain uncertain. This prospective, single-center study evaluated the utility of selective HOC based on the Charlson comorbidity index (CCI) in THA peri-operative management.</div></div><div><h3>Methods</h3><div>This study included 90 consecutive cases with primary THA by a single orthopedic surgeon. Based on CCI, patients were divided into an HOC group (CCI score ≥2) and non-HOC group (CCI score &lt;2). The HOC group received peri-operative care from a hospitalist and orthopedic surgeon, while non-HOC group was managed by an orthopedic surgeon alone. Medical and surgery-related complications, hospital length of stay, 30-day mortality, and costs were evaluated.</div></div><div><h3>Results</h3><div>There were 17 cases (19%) in the HOC group and 73 (81%) in non-HOC group. The mean CCI score was 3.1 ​± ​1.3 in the HOC group and 0.4 ​± ​0.5 in the non-HOC group. Medical complications were more frequent in the HOC group (35% <em>vs.</em> 4%), while surgery-related complications were comparable. No statistically significant difference was observed in length of stay, 30-day mortality, and costs.</div></div><div><h3>Conclusions</h3><div>Selective indication for HOC based on CCI effectively identified high-risk patients, enabling timely intervention for medical complications without prolonging hospital stay. This strategy may mitigate peri-operative medical risks while optimizing resource use.</div></div>","PeriodicalId":100795,"journal":{"name":"Journal of Joint Surgery and Research","volume":"3 3","pages":"Pages 128-131"},"PeriodicalIF":0.0,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proximal tibia bone mineral density correlates more closely with hip density in men with knee osteoarthritis","authors":"Junya Itou ,&nbsp;Ayano Kuwasawa ,&nbsp;Kotaro Nihei ,&nbsp;Ken Okazaki","doi":"10.1016/j.jjoisr.2025.06.001","DOIUrl":"10.1016/j.jjoisr.2025.06.001","url":null,"abstract":"<div><h3>Purpose</h3><div>Achieving biological fixation of the often loosened tibia is increasingly important for total knee arthroplasty (TKA), with one key factor being the bone density of the proximal tibia. This study examined whether hip bone mineral density (BMD), the most common diagnostic tool for osteoporosis, can estimate tibial BMD in both sexes.</div></div><div><h3>Methods</h3><div>This retrospective study included patients who underwent primary TKA with hip and tibial BMD measurement. Tibial BMD was measured 10 ​mm distal to the lateral tibial articular surface, separately for the medial (BMD_m) and lateral (BMD_l) sides. Additionally, the association between BMD and lower limb alignment was evaluated.</div></div><div><h3>Results</h3><div>In total, 1012 knees were included (79.3% in women). The mean patient age at surgery was 73.3 ​± ​7.5 years. The mean total hip BMD for women and men was 0.79 ​± ​0.13 ​g/cm² and 0.95 ​± ​0.16 ​g/cm², respectively. The mean BMD_m and BMD_l was, respectively, 0.75 ​± ​0.16 ​g/cm² and 0.63 ​± ​0.13 ​g/cm² in women and 0.92 ​± ​0.18 ​g/cm² and 0.89 ​± ​0.18 ​g/cm² in men. Both BMD_m and BMD_l showed a moderate correlation with hip BMD (<em>r</em> ​= ​0.67 and 0.66, respectively) in men. In women, BMD_m showed a weak correlation (<em>r</em> ​= ​0.47). Regarding lower limb alignment, BMD_m was significantly higher in varus alignment than in neutral or valgus alignment. BMD_l did not change with lower limb alignment.</div></div><div><h3>Conclusions</h3><div>BMD_m and BMD_l were moderately correlated with hip BMD in men, while BMD_m showed a low correlation in women.</div></div>","PeriodicalId":100795,"journal":{"name":"Journal of Joint Surgery and Research","volume":"3 3","pages":"Pages 121-127"},"PeriodicalIF":0.0,"publicationDate":"2025-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144335816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is anterosuperior cup overhang a risk factor for iliopsoas impingement after total hip arthroplasty? A radar chart analysis","authors":"Sakura Kuniyoshi ,&nbsp;Satoshi Nakasone ,&nbsp;Mika Takaesu ,&nbsp;Takahiro Igei ,&nbsp;Fumiyuki Washizaki ,&nbsp;Masamichi Onaga ,&nbsp;Masato Ishihara ,&nbsp;Kotaro Nishida","doi":"10.1016/j.jjoisr.2025.04.004","DOIUrl":"10.1016/j.jjoisr.2025.04.004","url":null,"abstract":"<div><h3>Purpose</h3><div>Groin pain is an occasional complication of total hip arthroplasty (THA), with iliopsoas impingement (IPI) often associated with irritation between the iliopsoas tendon and an overhanging acetabular cup. Although cup overhang is typically assessed using radiography or computed tomography (CT), a more precise evaluation of cup positioning within the acetabulum may improve IPI diagnosis. This study aimed to investigate the association between IPI and circumferential cup overhang using the radar chart method to determine the precise amount of cup overhang without being affected by the metal artifacts.</div></div><div><h3>Methods</h3><div>A total of 128 patients who underwent primary THA via the direct anterior approach between 2014 and 2023 were analyzed. Patients were divided into IPI and non-IPI groups. To eliminate the influence of metal artifacts, pre-operative CT with a computer-aided design model of the acetabulum cup was generated using image matching. Radial CT planes were created at 15° intervals, and the angles of edge of the acetabular cup (ACA) and acetabular rim (ARA) were measured in each plane. The acetabular rim was represented as a clock, and radar charts were generated for each group. Cup overhang was defined as locations where the ACA exceeded the ARA.</div></div><div><h3>Results</h3><div>The radar chart of the IPI group demonstrated significant cup overhang in the 1:30 location.</div></div><div><h3>Conclusions</h3><div>These result suggests that cup overhang in the anterosuperior region, particularly in the 1:30 location, is a risk factor for IPI following THA. The radar chart method provides a comprehensive evaluation of cup positioning and may serve as a valid evaluation tool for assisting IPI diagnosis.</div></div>","PeriodicalId":100795,"journal":{"name":"Journal of Joint Surgery and Research","volume":"3 2","pages":"Pages 113-120"},"PeriodicalIF":0.0,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Updates in the management of lateral patellar instability","authors":"Amber M. Parker ,&nbsp;Naofumi Hashiguchi ,&nbsp;Miho J. Tanaka","doi":"10.1016/j.jjoisr.2025.04.001","DOIUrl":"10.1016/j.jjoisr.2025.04.001","url":null,"abstract":"<div><h3>Purpose</h3><div>The purpose of this study was to review current concepts in the evaluation and management of lateral patellar instability, focusing on anatomical risk factors, diagnostic approaches, and treatment strategies.</div></div><div><h3>Methods</h3><div>A comprehensive review of the literature examining anatomical considerations, risk factors, diagnostic methods, and treatment options for patellar instability was conducted. The review focused on the medial patellofemoral complex (MPFC) anatomy, various imaging modalities, and conservative and surgical management approaches.</div></div><div><h3>Results</h3><div>Patellar instability involves multiple anatomical risk factors, including abnormalities in dynamic/static stabilizers, osseous restraints, and lower extremity alignment. The MPFC, consisting of the medial patellofemoral ligament (MPFL) and medial quadriceps tendon–femoral ligament, provides primary restraint against lateral instability in early knee flexion. While 94–100% of first-time dislocations involve MPFL injury and can be managed conservatively, patients with multiple risk factors show 70–90% recurrence rates. Surgical treatment through MPFC reconstruction shows low redislocation rates (1.8–4.5%) and may be combined with additional procedures such as tibial tubercle osteotomy, trochleoplasty, or alignment correction based on individual pathoanatomy.</div></div><div><h3>Conclusions</h3><div>Successful management of patellar instability requires a comprehensive evaluation of anatomical risk factors and individualized treatment approaches. While conservative management is appropriate for first-time dislocations without significant risk factors, surgical intervention through MPFC reconstruction and associated procedures shows promising outcomes in preventing recurrence and improving function in high-risk patients.</div></div>","PeriodicalId":100795,"journal":{"name":"Journal of Joint Surgery and Research","volume":"3 2","pages":"Pages 103-112"},"PeriodicalIF":0.0,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporal changes in synovitis and chronic pain after total knee arthroplasty: A two-year longitudinal study","authors":"Natsuki Sugimura,&nbsp;Koji Aso,&nbsp;Hiroyuki Wada,&nbsp;Masashi Izumi,&nbsp;Masahiko Ikeuchi","doi":"10.1016/j.jjoisr.2025.04.002","DOIUrl":"10.1016/j.jjoisr.2025.04.002","url":null,"abstract":"<div><h3>Purpose</h3><div>Chronic post-surgical pain (CPSP) following total knee arthroplasty (TKA) leads to significant patient dissatisfaction post-operatively. Previous cross-sectional research has identified post-TKA synovitis as a key factor influencing CPSP, but there is a lack of longitudinal data. This study aimed to analyze risk factors for post-TKA pain and synovitis, including pre-operative elements, to better understand their roles in CPSP.</div></div><div><h3>Methods</h3><div>A cohort of 49 knees from 42 patients undergoing TKA for osteoarthritis was assessed. Demographic data, pre-operative and post-operative radiographic findings, pre-operative magnetic resonance imaging, intra-operative blood loss, and post-operative C-reactive protein levels were documented. Chronic pain, measured using the WOMAC pain subscale, and synovitis, quantified by our original “total PD score” using power Doppler (PD) ultrasonography, were recorded pre-operatively and at six months, one year, and two years post-operatively. Multivariable analysis was used to identify factors contributing to chronic pain and synovitis at these time points.</div></div><div><h3>Results</h3><div>Multivariable analysis showed that the total PD score was significantly associated with chronic pain at one and two years post-TKA. Pre-operative WOMAC pain subscale scores were also significantly associated with chronic pain at one year. For synovitis, the pre-operative total PD score was associated at the two year mark, and body mass index (BMI) was found to be a contributing factor at six months, one year, and two years.</div></div><div><h3>Conclusions</h3><div>Greater overall synovitis on PD ultrasonography was significantly associated with chronic pain post-TKA. Greater pre-operative synovitis and lower BMI were identified as contributing factors to post-TKA synovitis on PD ultrasonography. Further research is warranted to explore additional unassessed factors influencing post-TKA synovitis and to enhance imaging assessments.</div></div>","PeriodicalId":100795,"journal":{"name":"Journal of Joint Surgery and Research","volume":"3 2","pages":"Pages 96-102"},"PeriodicalIF":0.0,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143924502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Robotic-assisted total knee arthroplasty: Systematic review of surgical assist robotic systems available in Japan","authors":"Keizo Wada ,&nbsp;Daisuke Hamada ,&nbsp;Yasuaki Tamaki ,&nbsp;Shota Shigekiyo ,&nbsp;Koichi Sairyo","doi":"10.1016/j.jjoisr.2025.04.003","DOIUrl":"10.1016/j.jjoisr.2025.04.003","url":null,"abstract":"<div><h3>Purpose</h3><div>Surgical assistant robots are now available for total knee arthroplasty (TKA). This review aimed to clarify the characteristics, accuracy, learning curve, and clinical results of robotic-assisted (RA) TKA performed using systems that are currently available in Japan (MAKO, ROSA, NAVIO/CORI, and VELYS).</div></div><div><h3>Methods</h3><div>The PubMed database was searched to identify studies on RA-TKA.</div></div><div><h3>Results</h3><div>MAKO is a semi-active robot using an oscillating saw. It is a computed tomography-based platform capable of determining the size and location of an implant pre-operatively. ROSA offers both imageless and image-based options using two-dimensional radiographs that are transformed into a three-dimensional model of the knee. NAVIO and CORI are handheld robotic platforms that support image-free anatomic data collection and streamlined intra-operative surgical planning with dynamic gap balancing. VELYS is an image-free, operating room bedrail-mounted, RA system that positions an oscillating saw for the surgeon to perform bone resection with real-time cut-plane tracking to compensate for any leg movement. Although there are some characteristic differences among the surgical assistant robots, the present review reveals that robot-controlled osteotomy may be more accurate than conventional techniques using a conventional guide and bone saw, with favorable short-term outcomes after RA-TKA.</div></div><div><h3>Conclusions</h3><div>This review found that the robotic systems recently made available in Japan demonstrate a high level of accuracy and show favorable short-term outcomes.</div></div>","PeriodicalId":100795,"journal":{"name":"Journal of Joint Surgery and Research","volume":"3 2","pages":"Pages 90-95"},"PeriodicalIF":0.0,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143924500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a wearable system to estimate knee adduction moment of patients with knee osteoarthritis during gait using a single inertial measurement unit","authors":"Ayako Akiba ,&nbsp;Kengo Harato ,&nbsp;Hiroshi Yoshihara ,&nbsp;Yu Iwama ,&nbsp;Kohei Nishizawa ,&nbsp;Takeo Nagura ,&nbsp;Masaya Nakamura","doi":"10.1016/j.jjoisr.2025.02.005","DOIUrl":"10.1016/j.jjoisr.2025.02.005","url":null,"abstract":"<div><h3>Purpose</h3><div>The external knee adduction moment (KAM) during gait is an important mechanical factor for knee osteoarthritis (KOA). Three-dimensional motion capture (MoCap) has been used to measure KAM, but it has limitations including cost, measuring time, and space. The purpose of this study was to develop a simple and wearable system to estimate KAM.</div></div><div><h3>Methods</h3><div>Thirty-nine female and seven male subjects diagnosed with KOA were included. Simultaneous measurements of 5 ​m walk using MoCap and inertial measurement unit (IMU) attached to the knee were performed, and a deep learning algorithm based on a gait phase detection algorithm and one-dimensional convolutional neural network model was used to estimate KAM. In addition, the reliability of the artificial intelligence system was also evaluated.</div></div><div><h3>Results</h3><div>The mean absolute percent error (MAPE) and mean absolute error (MAE) of estimated KAM peak of the training data and test datasets were 13.0% and 0.0428 Nm.s/(BW∗Ht) and 17.3% and 0.0505 Nm.s/(BW∗Ht), respectively, and those of estimated KAM impulse were 20.4% and 0.0214 Nm.s/(BW∗Ht) and 21.4% and 0.0212 Nm.s/(BW∗Ht), respectively. The Pearson correlation coefficients between estimated KAM (peak, impulse) and MoCap KAM (peak, impulse) were 0.870 and 0.975 in the training dataset and 0.591 and 0.690 in the test dataset. The intraclass correlation coefficients (ICCs) of estimated KAM impulse were 0.83, 0.94, 0.70, and 0.82 for ICCs (1.1), (1,k), (2,1), and (2,k) respectively.</div></div><div><h3>Conclusions</h3><div>The wearable system showed reasonable accuracy and reliability in estimating KAM of KOA during gait. The simple equipment in the system enables the measurement of KAM during daily practice in the clinic or hospital if there is available space to walk 5 ​m.</div></div>","PeriodicalId":100795,"journal":{"name":"Journal of Joint Surgery and Research","volume":"3 2","pages":"Pages 84-89"},"PeriodicalIF":0.0,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143683644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of early implant failure in Japanese patients undergoing unrestricted kinematic alignment total knee arthroplasty","authors":"Shuji Toyono ,&nbsp;Shigenobu Fukushima ,&nbsp;Takao Yamamoto ,&nbsp;Takashi Ito ,&nbsp;Takahiro Miyaji ,&nbsp;Akemi Suzuki ,&nbsp;Michiaki Takagi","doi":"10.1016/j.jjoisr.2025.02.004","DOIUrl":"10.1016/j.jjoisr.2025.02.004","url":null,"abstract":"<div><h3>Purpose</h3><div>Total knee arthroplasty (TKA) traditionally involves mechanical alignment with a target range of ±3°. However, unrestricted kinematic alignment (urKA) has emerged as a viable alternative, potentially maintaining a favorable implant survival rate without the constraints of neutral alignment. Japanese people have more pronounced tibial varus than other populations. This study evaluated early implant failures in Japanese patients with osteoarthritis who underwent urKA-TKA.</div></div><div><h3>Methods</h3><div>In this study, 557 knees of 460 patients who underwent urKA-TKA between June 2019 and September 2021 were retrospectively analyzed. Surgeries were conducted by four surgeons using standardized urKA techniques, ensuring consistent ligament balancing and component positioning. The primary outcome was the rate of revision for aseptic loosening over at least 2 years, with secondary outcomes focusing on post-operative alignment.</div></div><div><h3>Results</h3><div>The follow-up rate was 95%, with a mean of 3.0 years. The implant survival rate was 100% considering implant revision as the endpoint, and 99% when re-operation was included. Post-operative alignment revealed that 60.3% of tibial components and 39.3% of limbs had varus alignment exceeding 3°; however, this did not compromise implant survival during the follow-up period.</div></div><div><h3>Conclusions</h3><div>The follow-up of at least 2 years for urKA-TKA in a Japanese cohort demonstrated no early implant failures with no significant effect on outcomes from deviations in varus alignment. These results support the use of urKA-TKA and underscore the need for long-term studies to further substantiate these findings in the Japanese population.</div></div>","PeriodicalId":100795,"journal":{"name":"Journal of Joint Surgery and Research","volume":"3 2","pages":"Pages 79-83"},"PeriodicalIF":0.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143683645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}