The present study describes the case of a male adult with an osteosarcoma in the proximal tibia, treated with limb salvage with endoprosthesis and chemotherapy. The patient developed an unusual metastatic pattern compromising the liver, bone, and inguinal lymph nodes, without local recurrence in the tibia or pulmonary metastases. Osteosarcoma (OS) is the second most frequent primary bone tumor after multiple myeloma in adults. Frequent sites of metastases in case of disease progression are the lungs and bone. Extrapulmonary metastases are rare. The development of new schemes of chemotherapy have improved life expectancy in osteosarcoma patients but have also altered the usual patterns of metastases, resulting in unusual metastatic locations.

UNASSIGNED: Lower extremity bone stress injuries (BSI) are common injuries among athletes and military members. Typical management involves a period of restricted weightbearing which can have rapid detrimental effects upon both muscle and bone physiology. Few studies have investigated the effect of blood flow restriction (BFR) training on bone in the rehabilitative setting.
UNASSIGNED: The purpose of this study was to investigate the effects of lower extremity exercise with the addition of BFR upon bone mineral density, bone mineral content, and lean body mass in military members with tibial BSIs.
UNASSIGNED: Case series.
UNASSIGNED: Twenty military members with MRI-confirmed tibial BSI were recruited to complete lower extremity exercise with the addition of BFR twice per week for four weeks. The BFR cuff was applied proximally to the participant\'s involved limb while they performed gluteal, thigh, and leg resistance exercises. Outcomes were assessed at baseline and four weeks. The primary outcomes were whole leg bone mineral density (BMD), bone mineral content (BMC), and lean body mass (LM) as measured by dual-energy x-ray absorptiometry. Secondary outcomes included thigh and leg circumference measures and patient-reported outcomes, including the Lower Extremity Functional Scale (LEFS), Patient-Reported Outcomes Measurement Information System 57 (PROMIS-57), and Global Rating of Change (GROC).
UNASSIGNED: No significant differences were found in BMD (p=0.720) or BMC (p=0.749) between limbs or within limbs over time. LM was generally less in the involved limb (p=0.019), however there were no significant differences between or within limbs over time (p=0.404). For thigh circumference, significant main effects were found for time (p=0.012) and limb (p=0.015), however there was no significant interaction effect (p=0.510). No significant differences were found for leg circumference (p=0.738). Participants showed significant mean changes in LEFS (15.15 points), PROMIS physical function (8.98 points), PROMIS social participation (7.60 points), PROMIS anxiety (3.26 points), and PROMIS pain interference (8.39 points) at four weeks.
UNASSIGNED: The utilization of BFR in the early rehabilitative management of tibial BSI may help mitigate decrements in both bone and muscle tissue during periods of decreased physical loading.
UNASSIGNED: 4.

The use of a filling block can improve the initial stability of the fixation plate in the open wedge high tibial osteotomy (OWHTO), and promote bone healing. However, the biomechanical effects of filling block structures and materials on OWHTO remain unclear. OWHTO anatomical filling block model was designed and built. The finite element analysis method was adopted to study the influence of six filling block structure designs and four different materials on the stress of the fixed plate, tibia, screw, and filling block, and the micro-displacement at the wedge gap of the OWHTO fixation system. After the filling block was introduced in the OWHTO, the maximum von Mises stress of the fixation plate was reduced by more than 30%, the maximum von Mises stress of the tibia decreased by more than 15%, and the lateral hinge decreased by 81%. When the filling block was designed to be filled in the posterior position of the wedge gap, the maximum von Mises stress of the fixation system was 97.8 MPa, which was smaller than other filling methods. The minimum micro-displacement of osteotomy space was -2.9 μm, which was larger than that of other filling methods. Compared with titanium alloy and tantalum metal materials, porous hydroxyapatite material could obtain larger micro-displacement in the osteotomy cavity, which is conducive to stimulating bone healing. The results demonstrate that OWHTO with a filling block can better balance the stress distribution of the fixation system, and a better fixation effect can be obtained by using a filling block filled in the posterior position. Porous HA used as the material of the filling block can obtain a better bone healing effect.
使用填充块可以改善开放式胫骨高位截骨术（OWHTO）初始稳定性，促进骨愈合。然而，填充块结构及材料对OWHTO的生物力学影响依然不清楚。本文通过对OWHTO解剖型填充块进行设计建模，采用有限元方法，研究了填充块结构及材料对OWHTO固定系统固定板、胫骨、螺钉、填充块的应力和楔形间隙处的微位移影响。在OWHTO引入填充块后固定板最大应力降低了30%以上，胫骨最大应力下降了15%以上，外侧铰链区域最大应力下降了81%。填充块采用楔形间隙后侧位置填充设计时，固定系统最大应力为97.8 MPa，明显小于其他填充方式，且截骨间隙微位移最小为–2.9 μm，大于其他填充方式。与钛合金和钽金属相比，填充块采用多孔羟基磷灰石（HA）时可获得较大的截骨开口间隙微位移以刺激骨愈合。本研究结果表明OWHTO固定系统引入填充块更好地平衡了整体的应力分布，填充块结构采用楔形间隙后侧位置填充设计可以获得更优的固定效果，填充块材料采用多孔HA时骨愈合效果会更好。.

Many studies have reported the risk factors associated with primary anterior cruciate ligament (ACL) injury. However, few studies have focused on the bony morphology of secondary ipsilateral injury after ACL reconstruction. This study aimed to investigate the morphological risk factors of the proximal tibia contributing to secondary ipsilateral injury after ACL reconstruction. Twenty patients who were selected from secondary ipsilateral injury after ACL reconstruction between January 2015 and May 2020 were included in the secondary injury group. They were matched in a 1:2 ratio to the control group, which underwent primary ACL reconstruction during the same period and did not experience reinjury at the minimum 2-year follow-up, based on age, gender, and body mass index. All parameters, including medial tibial posterior slope, lateral tibial posterior slope (LTPS), medial tibial plateau depth, and lateral tibial plateau height, were recorded by using magnetic resonance imaging. Binary logistic regression analysis and receiver operator characteristic curves were conducted to explore the risk factors for reinjury and determine the cutoff value for the significant parameter. The LTPS was significantly larger in the secondary injury group than in the control group (9.6 ± 1.5° to 7.0 ± 1.4°, P < .001), and there was no significant difference in the medial tibial posterior slope, medial tibial posterior slope, and lateral tibial plateau height between the 2 groups (P > .05). The LTPS was found to be an independent risk factor for secondary ipsilateral injury after ACL reconstruction (odds ratio = 3.220, 95% confidence interval = 1.904-5.446, P < .001). The cutoff value of the LTPS was 8.8°, with a sensitivity of 91.7% and a specificity of 81.2%. The LTPS could be a unique predictor of secondary ipsilateral injury after ACL reconstruction. Orthopedists should implement effective measurements during primary reconstruction when the LTPS is >8.8°.

This prospective bi-center study aimed to analyze the outcomes of primary total knee arthroplasty using the Stemmable Tibia Attune system. A total of 100 patients who underwent primary total knee arthroplasty with Stemmable Tibia from January 2019 to December 2021 were enrolled in the study. Radiological outcomes (hip-knee-ankle axis and medial proximal tibial angle) were assessed preoperatively and postoperatively. Clinical outcomes (visual analog scale score, Hospital for Special Surgery score, Knee Society function score, Knee Society knee score, flexion contracture, further flexion, and range of motion) were analyzed preoperatively and at 6 weeks, 3 months, 6 months, 1 year, and 2 years postoperatively. Complications (periprosthetic joint infection and aseptic loosening) were examined. The hip-knee-ankle axis decreased (preoperative: 9.5° ± 6.3°, postoperative: 1.1° ± 2.7°), whereas the medial proximal tibial angle increased (preoperative: 84.6° ± 4.1°, postoperative: 89.8° ± 1.9°). The visual analog scale score, Hospital for Special Surgery score, Knee Society knee score, and Knee Society function score increased postoperatively. The Knee Society knee score indicated above good outcomes (100.0% and 99.0% at 1 and 2 years postoperatively, respectively). The Knee Society function score also showed above good results (98.0% and 93.0% at 1 and 2 years postoperatively, respectively). The range of motion significantly improved (p < 0.001): flexion contracture decreased from 9.10° ± 7.23° to 2.15° ± 2.87°, whereas further flexion increased from 136.05° ± 14.78° to 139.80° ± 10.02°. One patient developed periprosthetic joint infection; no early loosening was observed. In conclusion, Attune primary total knee arthroplasty with Stemmable Tibia not only is safe and effective but also leads to radiological and clinical improvements.

Total knee arthroplasty (TKA) is a well-established and successful treatment option for patients with end-stage osteoarthritis of the knee, providing high patient satisfaction. Robotic systems have been widely adopted to perform TKA in orthopaedic centres. The exact spatial positions of the femur and tibia are usually determined through pinned trackers, providing the surgeon with an exact illustration of the axis of the lower limb. The drilling of holes required for mounting the trackers creates weak spots, causing adverse events such as bone fracture. In the presented computational feasibility study, time differential electrical impedance tomography is used to locate the femur positions, thereby the difference in conductivity distribution between two distinct states s0 and s1 of the measured object is reconstructed. The overall approach was tested by simulating five different configurations of thigh shape and considered tissue conductivity distributions. For the cylinder models used for verification and reference, the reconstructed position deviated by about ≈1 mm from the actual bone centre. In case of models mimicking a realistic cross section of the femur position deviated between 7.9 mm 24.8 mm. For all models, the bone axis was off by about φ=1.50° from its actual position.

Background and Objectives: Hyperglycemia is known to undermine the osteointegration process of implants. In this study, the effects of mangiferin (MF) on the post-implant osteointegration process in a type-II diabetes model were investigated molecularly and morphologically. Materials and Methods: Sprague Dawley male rats were divided into three groups: control, diabetes, and diabetes + MF. All animals were implanted in their tibia bones on day 0. At the end of the 3-month experimental period, the animals\' blood and the implant area were isolated. Biochemical measurements were performed on blood samples and micro-CT, qRT-PCR, histological, and immunohistochemical measurements were performed on tibia samples. Results: MF significantly improved the increased glucose, triglyceride-VLDL levels, and liver enzymes due to diabetes. By administering MF to diabetic rats, the osteointegration percentage and bone volume increased while porosity decreased. DKK1 and BMP-2 mRNA expressions and OPN, OCN, and OSN mRNA-protein expressions increased by MF administration in diabetic rats. Additionally, while osteoblast and osteoid surface areas increased with MF, osteoclast and eroded surface areas decreased. Conclusions: The findings of our study indicate that MF will be beneficial to the bone-repairing process and osteointegration, which are impaired by type-II diabetes.

BACKGROUND: Accurate estimation of implant size before surgery is crucial in preparing for total knee arthroplasty. However, this task is time-consuming and labor-intensive. To alleviate this burden on surgeons, we developed a reliable artificial intelligence (AI) model to predict implant size.
METHODS: We enrolled 714 patients with knee osteoarthritis who underwent total knee arthroplasty from March 2010 to February 2014. All surgeries were performed by the same surgeon using implants from the same manufacturer. We collected 1412 knee anteroposterior (AP) and lateral view x-ray images and retrospectively investigated the implant size. We trained the AI model using both AP and lateral images without any clinical or demographic information and performed data augmentation to resolve issues of uneven distribution and insufficient data. Using data augmentation techniques, we generated 500 images for each size of the femur and tibia, which were then used to train the model. Using data augmentation techniques, we generated 500 images for each size of the femur and tibia, which were then used to train the model. We used ResNet-101 and optimized the model with the aim of minimizing the cross-entropy loss function using both the Stochastic Gradient Descent (SGD) and Adam optimizer.
RESULTS: The SGD optimizer achieved the best performance in internal validation. The model showed micro F1-score 0.91 for femur and 0.87 for tibia. For predicting within ± one size, micro F1-score was 0.99 for femur and 0.98 for tibia.
CONCLUSIONS: We developed a deep learning model with high predictive power for implant size using only simple x-ray images. This could help surgeons reduce the time and labor required for preoperative preparation in total knee arthroplasty. While similar studies have been conducted, our work is unique in its use of simple x-ray images without any other data, like demographic features, to achieve a model with strong predictive power.

UNASSIGNED: To compare the effectiveness of I.D.E.A.L technique and transtibial (TT) technique in anterior cruciate ligament (ACL) reconstruction.
UNASSIGNED: A clinical data of 60 patients with ACL injury, who were admitted and met the selection criteria between January 2020 and September 2022, was retrospectively analyzed. All patients underwent arthroscopic ACL reconstruction with autologous tendon. During operation, the femoral tunnel was prepared by using I.D.E.A.L technique in 30 cases (I.D.E.A.L group) and using TT technique in 30 cases (TT group). There was no significant difference in baseline data such as age, gender, body mass index, cause of injury, injured side, interval from injury to operation, constituent ratio of combined cartilage and meniscus injury, and preoperative Lysholm score, International Knee Documentation Committee (IKDC) score, visual analogue scale (VAS) score, anterior tibial translation difference, and Blumensaat angle between the two groups ( P>0.05). The length of hospital stay and the occurrence of early and late complications were recorded. During follow-up, the Lysholm score, IKDC score, and VAS score were used to evaluate knee joint function and pain degree, and the anterior tibial translation difference was measured. MRI reexamination was performed to observe the healing of the graft, and the signal to noise quotient (SNQ) values of the femoral end, middle section, and tibial end of the graft, as well as the Blumensaat angle of the knee joint were measured. The differences in tibial anterior translation difference and Blumensaat angle before and after operation (change values) were calculated and compared between the two groups.
UNASSIGNED: The incisions in both groups healed by first intention after operation, and there was no significant difference in the length of hospital stay between the two groups ( P>0.05). All patients were followed up 12-18 months, with an average of 14.9 months. The Lysholm score and IKDC score of the knee joint in both groups after operation increased when compared with those before operation, and the VAS score decreased. Compared to preoperative scores, except for the VAS score of the TT group at 1 week after operation ( P>0.05), there were significant differences in all scores at different time points postoperatively in the two groups ( P<0.05). The above scores in both groups showed a further improvement trend with the prolongation of time after operation. There were significant differences in Lysholm score and VAS score among 1 week, 1 month, 3 months, 6 months, and 12 months after operation in the two groups ( P<0.05). The IKDC score of both groups at 1 month after operation was significantly different from that at 1 week after operation ( P<0.05). At 1 week after operation, the Lysholm score and IKDC score in the I.D.E.A.L group were significantly higher than those in the TT group ( P<0.05), and the VAS score was significantly lower ( P<0.05); there was no significant difference between the two groups at 1, 3, 6, and 12 months after operation ( P>0.05). At 12 months after operation, the anterior tibial translation differences in both groups were significantly lower than those before operation ( P<0.05); and the change value in the I.D.E.A.L group was significantly higher than that in the TT group ( P<0.05). The incidences of early and late complications in the I.D.E.A.L group were significantly lower than those in the TT group ( P<0.05). At 12 months after operation, MRI examination showed that the grafts of the knee joint in both groups survived well, and the Blumensaat angles of both groups were significantly smaller than those before operation ( P<0.05). The change value of the Blumensaat angle in the I.D.E.A.L group was significantly higher than that in the TT group ( P<0.05). The SNQ values of the femoral end, middle section, and tibial end of the graft in the I.D.E.A.L group were significantly higher than those in the TT group ( P<0.05).
UNASSIGNED: The early effectiveness of ACL reconstruction by using the I.D.E.A.L technique is better, the knee joint is more stable, and the incidence of postoperative complication is lower. However, the maturity of the graft after reconstruction using the TT technique is higher.
UNASSIGNED: 比较I.D.E.A.L技术与经胫骨隧道（transtibial，TT）技术重建前交叉韧带（anterior cruciate ligament，ACL）的疗效。.
UNASSIGNED: 回顾分析2020年1月—2022年9月收治且符合选择标准的60例ACL损伤患者临床资料。患者均接受关节镜下自体肌腱重建ACL，术中股骨隧道定位采用I.D.E.A.L技术30例（I.D.E.A.L组）、TT技术30例（TT组）。两组患者年龄、性别、身体质量指数、致伤原因、损伤侧别、受伤至手术时间、合并软骨及半月板损伤构成比以及术前Lysholm评分、国际膝关节文献委员会（IKDC）评分、疼痛视觉模拟评分（VAS）、胫骨前移差值、Blumensaat角等基线资料比较，差异均无统计学意义（ P>0.05）。记录住院时间、术后早/远期并发症发生情况，采用Lysholm评分、IKDC评分及VAS评分评价膝关节功能及疼痛程度，测量胫骨前移差值；MRI复查观察移植物愈合情况，并测量移植物股骨端、中段、胫骨端信噪比（signal to noise quotien，SNQ）值，以及膝关节Blumensaat角。计算胫骨前移差值以及Blumensaat角的手术前后差值（变化值）进行组间比较。.
UNASSIGNED: 术后两组切口均Ⅰ期愈合，住院时间组间差异无统计学意义（ P>0.05）。患者均获随访，随访时间12～18个月，平均14.9个月。术后两组膝关节Lysholm评分、IKDC评分均较术前增加，VAS评分降低，其中TT组术后1周VAS评分与术前差异无统计学意义（ P>0.05），其余评分两组组内与术前差异均有统计学意义（ P<0.05）。术后随时间延长，两组上述评分均呈进一步改善趋势；Lysholm评分、VAS评分术后1周及1、3、6、12个月间差异均有统计学意义（ P<0.05），IKDC评分仅术后1个月与术后1周差异有统计学意义（ P<0.05）。术后1周I.D.E.A.L组膝关节Lysholm评分、IKDC评分高于TT组、VAS评分更低，差异均有统计学意义（ P<0.05）；1、3、6、12个月两组间差异均无统计学意义（ P>0.05）。术后12个月，两组胫骨前移差值均较术前降低（ P<0.05）；且I.D.E.A.L组变化值高于TT组，差异有统计学意义（ P<0.05）。 I.D.E.A.L组术后早、远期并发症发生率均低于TT组（ P<0.05）。术后12个月MRI检查示两组膝关节移植物均生存良好，Blumensaat角均较术前降低（ P<0.05），且I.D.E.A.L组Blumensaat角变化值以及移植物股骨端、中段、胫骨端SNQ值均高于TT组（ P<0.05）。.
UNASSIGNED: 采用I.D.E.A.L技术重建ACL术后早期疗效更好，膝关节稳定性更高，术后并发症率更低；但采用TT技术重建术后移植物成熟度更高。.

BACKGROUND: Unicompartmental knee arthroplasty (UKA) has been proved to be a successful treatment for osteoarthritis patients. However, the stress shielding caused by mismatch in mechanical properties between human bones and artificial implants remains as a challenging issue. This study aimed to properly design a bionic porous tibial implant and evaluate its biomechanical effect in reconstructing stress transfer pathway after UKA surgery.
METHODS: Voronoi structures with different strut sizes and porosities were designed and manufactured with Ti6Al4V through additive manufacturing and subjected to quasi-static compression tests. The Gibson-Ashby model was used to relate mechanical properties with design parameters. Subsequently, finite element models were developed for porous UKA, conventional UKA, and native knee to evaluate the biomechanical effect of tibial implant with designed structures during the stance phase.
RESULTS: The internal stress distribution on the tibia plateau in the medial compartment of the porous UKA knee was found to closely resemble that of the native knee. Furthermore, the mean stress values in the medial regions of the tibial plateau of the porous UKA knee were at least 44.7% higher than that of the conventional UKA knee for all subjects during the most loading conditions. The strain shielding reduction effect of the porous UKA knee model was significant under the implant and near the load contact sites. For subject 1 to 3, the average percentages of nodes in bone preserving and building region (strain values range from 400 to 3000 μm/m) of the porous UKA knee model, ranging from 68.7 to 80.5%, were higher than that of the conventional UKA knee model, ranging from 61.6 to 68.6%.
CONCLUSIONS: The comparison results indicated that the tibial implant with designed Voronoi structure offered better biomechanical functionality on the tibial plateau after UKA. Additionally, the model and associated analysis provide a well-defined design process and dependable selection criteria for design parameters of UKA implants with Voronoi structures.