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Background: Recent studies have reported that lateral hinge fracture (LHF) has a negative effect on bone healing at the osteotomy site after medial closing wedge distal femoral osteotomy (MCDFO). However, limited evidence exists in the literature regarding the predictive factors for LHF in MCDFO. Hypothesis: A large medial closing gap and a lateral hinge position in the supracondylar area would increase plain radiography–based and/or computed tomography (CT)–based LHF in MCDFO. Study Design: Case control study; Level of evidence, 3. Methods: We retrospectively evaluated 67 knees of 53 patients (mean age, 37.4 ± 16.9 years) who underwent MCDFO between May 2009 and June 2021. The surgical indications for MCDFO were genu valgum deformity combined with either lateral compartment osteoarthritis or recurrent patellar dislocation. The presence of LHF was evaluated based on immediate postoperative plain radiography and CT scans. The predictive factors for LHF in MCDFO were investigated using multivariate logistic regression analysis. Results: LHFs were identified in 21 knees (31.3%) through plain radiography and in 40 knees (59.7%) through CT. Multivariate logistic regression analysis showed that the medial closing gap and lateral hinge position were predictive factors for plain radiography– and CT-based LHF after MCDFO. Controlling for other variables, we found that an increase in the medial opening gap by 1 mm increased the likelihood of plain radiography–based LHF by a factor of 1.805 (95% CI, 1.291-2.525; P = .001) and CT-based LHF by 1.333 (95% CI, 1.003-1.772; P = .048). Moreover, a lateral hinge position in the supracondylar area increased the likelihood of plain radiography–based LHF by a factor of 9.870 (95% CI, 2.179-44.720; P = .003) and CT-based LHF by 5.686 (95% CI, 1.124-28.754; P = .036). Conclusion: A large medial closing gap and lateral hinge position in the supracondylar area are associated with LHF in MCDFO. Care should be taken to prevent LHF in MCDFO with a large medial closing gap. Moreover, a lateral hinge position in the supracondylar area should be avoided to decrease the incidence of LHF in MCDFO.

The meniscus is a semilunar fibrocartilage structure that plays important roles in maintaining normal knee biomechanics and function. The roles of the meniscus, including load distribution, force transmission, shock absorption, joint stability, lubrication, and proprioception, have been well established. Injury to the meniscus can disrupt overall joint stability and cause various symptoms including pain, swelling, giving-way, and locking. Unless treated properly, it can lead to early degeneration of the knee joint. Because meniscal injuries remain a significant challenge due to its low intrinsic healing potential, most notably in avascular and aneural inner two-thirds of the area, more efficient repair methods are needed. Mesenchymal stem cells (MSCs) have been investigated for their therapeutic potential in vitro and in vivo. Thus far, the application of MSCs, including bone marrow-derived, synovium-derived, and adipose-derived MSCs, has shown promising results in preclinical studies in different animal models. These preclinical studies could be categorized into intra-articular injection and tissue-engineered construct application according to delivery method. Despite promising results in preclinical studies, there is still a lack of clinical evidence. This review describes the basic knowledge, current treatment, and recent studies regarding the application of MSCs in treating meniscal injuries. Future directions for MSC-based approaches to enhance meniscal healing are suggested.

Tibiofemoral synchronization technique matches the rotational alignment of the tibial component to the femoral component during the total knee arthroplasty (TKA). The rotational axis of the proximal tibia can be changed by this technique, which affects tibial torsion postoperatively. The purpose of this study was to investigate whether the tibiofemoral synchronization technique affect the tibial torsion, and the lower limb rotation after primary TKA. It was hypothesised that the tibial torsion would change after primary TKA. Ninety-three posterior stabilised TKAs from 89 patients were included from January 2017 to December 2018. Mechanical hip–knee–ankle axis (mHKA), in plain radiographs, femoral anteversion, tibial torsion, femoral neck-malleolar angle (FNMA), and rotational alignment of the femoral and the tibial components in pre- and postoperative CT scans were measured by two blinded observers. The primary outcome was a postoperative change in femoral anteversion, tibial torsion and FNMA. Clinical outcomes were evaluated using the American Knee Society Knee Score (AKSKS)/Function Score (AKSFS), and Oxford Knee Score (OKS) preoperatively and at 1 year after TKA. Patients’ perception of changes in the foot progression angle after TKA was investigated. Statistical significance was set at p

Background This study investigated the epidemiology and causes of bearing dislocations following mobile-bearing unicompartmental knee arthroplasty (MUKA) and determined whether the incidence of primary bearing dislocations decreases as surgeon experience increases. Methods We retrospectively reviewed the bearing dislocations following MUKAs performed by 14 surgeons with variable experience levels. Causes of bearing dislocations were determined based on the surgical records, radiographs, and operator’s suggestion. Using a chi-squared test, the incidence of bearing dislocation was compared between the first 50, the second 50, and the next 100 unicompartmental knee arthroplasties (UKAs) of each surgeon's cohort. Results There were 67 (3.6%) bearing dislocations from 1853 MUKAs. The mean time to bearing dislocations after index MUKAs was 33 months (range, 1-144 months); 55% of the bearing dislocations occurred within 2 years after the index MUKAs. Primary bearing dislocations (n = 58) were the most common, followed by secondary (n = 6) and traumatic dislocations (n = 3). There was no significant difference in the incidence of bearing dislocation between the first 50 and second 50 UKAs for each surgeon. Two surgeons showed a significant decrease in bearing dislocations in their second 100 UKAs, while the other surgeons did not show a difference between their first 100 and second 100 UKAs. Conclusion Most bearing dislocations after MUKAs were related to technical errors such as component malposition or gap imbalance. This study did not confirm that the incidence of bearing dislocations decreases as the number of cases increases. Level of Evidence IV, Case series.

To date, few studies have investigated the feasibility of the loop-mediated isothermal amplification (LAMP) assay for identifying pathogens in tissue samples. This study aimed to investigate the feasibility of LAMP for the rapid detection of methicillin-susceptible or methicillin-resistantTwenty tissue samples infected with either MSSA (n = 10) or MRSA (n = 10) were obtained from patients who underwent orthopedic surgery for suspected musculoskeletal infection between December 2019 and September 2020. DNA was extracted from the infected tissue samples using the bead-beating method. A multiplex LAMP assay was conducted to identify MSSA and MRSA infections. To recognize theThe LAMP result was positive for samples containing 10The results of this study suggest that the LAMP assay performed with tissue DNA samples can be a useful diagnostic method for the rapid detection of musculoskeletal infections caused by MSSA and MRSA.

Background: The tibial tuberosity (TT) in the axial plane is located on a curved line along the anterior cortex of the proximal tibia. Therefore, the linear measurement of TT position may not fully reflect TT malposition. Purpose: To introduce TT–rotational angle (TT-RA) as a new anatomical parameter, which means the rotation of the TT relative to the dorsal condylar line of the tibia, and to validate its predictive value for patellar dislocation. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Included were 46 patients with a history of patellar dislocation and 46 age- and sex-matched controls who underwent axial magnetic resonance imaging. Seven radiological parameters were measured and compared between the 2 groups, including TT–trochlear groove (TT-TG) distance, tibial tubercle–posterior cruciate ligament (TT-PCL) distance, TT-PCL ratio, TT lateralization (TTL), trochlear groove medialization (TGM), TT-RA, trochlear groove–posterior condylar axis angle (TG-PCA), and knee rotation. The predictive values of parameters for patellar dislocation were assessed using multiple logistic regression analysis. Results: The intra- and interobserver correlation coefficients for measuring the radiographic parameters showed good to excellent values., respectively. There were significant differences in the TT-TG distance (13.9 vs 6.8 mm; P < .001), TT-RA (16.0° vs 9.1°; P < .001), TG-PCA (93.7° vs 95.4°; P = .017), and knee rotation (0.9° vs 5.3°; P < .001) between the 2 groups. However, there was no significant difference in TT-PCL distance (20.7 vs 19.4 mm; P = .075), TT-PCL ratio (28.0% vs 26.6%; P = .136), TTL (65.7% vs 64.9%; P = .270), or TGM (54.9% vs 55.0%; P = .923). Multivariable analysis showed that 3 parameters were significantly associated with patellar dislocation: TT-RA (OR, 1.57; P < .001), TT-TG distance (OR, 1.52; P = .002), and knee rotation (OR, 0.75; P = .022). Conclusion: The TT-RA was a reliable predisposing parameter of patellar instability. It can be an alternative method of measurement when the TT-TG distance is not clearly defined.

Background: Limited evidence exists in the literature regarding the detection rates of lateral hinge fracture (LHF) on computed tomography (CT) after medial closing wedge distal femoral osteotomy (MCDFO). Moreover, the effect of LHF on bone healing after MCDFO remains unclear. Hypothesis: The detection rates of LHF after MCDFO would be higher on CT than on plain radiography. The incidence of problematic bone healing would be higher in the knees with LHF than in those without LHF. Study Design: Cohort study (diagnosis), Level of evidence, 3. Methods: Patients who underwent MCDFO between May 2009 and July 2019 were retrospectively evaluated. The presence of LHF was evaluated using immediate postoperative plain radiography and CT. The detection rates of LHF on plain radiography and CT were compared. The incidence of problematic bone healing (nonunion, delayed union, and loss of correction) was also compared between the knees with LHF and those without LHF. Results: A total of 55 knees of 43 patients (mean age, 37.7 ± 16.7 years) were included in the study. Although 33 LHFs were detected on CT, only 19 LHFs were detected on plain radiography. The detection rate of LHF was significantly higher on CT than on plain radiography (60% vs 34.5%; P = .008). At 1-year follow-up, 10 cases of problematic bone healing (1 nonunion, 4 delayed unions, and 5 losses of correction) were identified. The incidence of problematic bone healing was significantly higher in the knees with LHF than in those without LHF as shown on plain radiography (36.8% vs 8.3%; P = .001) and CT (30.3% vs 0%; P = .004). Conclusion: LHF can be detected better on CT than on plain radiography and has a negative effect on bone healing after MCDFO. For patients with LHF detected on either plain radiography or CT, careful rehabilitation with close follow-up is recommended.

Background: Although the use of adjustable-loop suspensory fixation has increased in recent years, the influence of the shortcomings of suspensory fixation, such as the bungee-cord or windshield-wiper effects, on tunnel widening remains to be clarified. Hypothesis/Purpose: The purpose of this study was to compare adjustable-loop femoral cortical suspensory fixation and interference screw fixation in terms of tunnel widening and clinical outcomes after anterior cruciate ligament reconstruction (ACLR). We hypothesized that tunnel widening in the adjustable-loop femoral cortical suspensory fixation (AL) group would be comparable to that in the interference screw fixation (IF) group. Methods: This study evaluated patients who underwent primary ACLR at our institution between March 2015 and June 2019. The femoral and tibial tunnel diameters were measured using plain radiographs in the immediate postoperative period and 2 years after ACLR. Tunnel widening and clinical outcomes (Lysholm score, 2000 International Knee Documentation Committee subjective score, and Tegner activity level) were compared between the two groups. Results: There were 48 patients (mean age, 29.8 ± 12.0 years) in the AL group and 44 patients (mean age, 26.0 ± 9.5 years) in the IF group. Tunnel widening was significantly greater in the AL group than that in the IF group at the tibia anteroposterior (AP) middle (2.03 mm vs. 1.32 mm, p = 0.017), tibia AP distal (1.52 mm vs. 0.84 mm, p = 0.012), tibia lateral proximal (1.85 mm vs. 1.00 mm, p = 0.001), tibia lateral middle (2.36 mm vs. 1.03 mm, p < 0.001), and tibia lateral distal (2.34 mm vs. 0.85 mm, p < 0.001) levels. There were no significant differences between the two groups with respect to femoral tunnel widening and clinical outcomes. Conclusions: Tibial tunnel widening was significantly greater in the AL group than in the IF group at 2 years after primary ACLR. However, the clinical outcomes in the two groups were comparable at 2 years.

Background Few studies have reported the clinical outcomes of the medial reefing procedure and lateral release with arthroscopic control of medial retinacular tension in patients with recurrent patellar dislocation. The purpose of this study was to investigate the clinical, radiologic outcomes and complications of arthroscopy-controlled medial reefing and lateral release. Methods Patients who underwent arthroscopy-controlled medial reefing and lateral release for recurrent patellar dislocation between November 2007 and June 2017 were retrospectively evaluated. The clinical outcome (Kujala score), radiologic outcome (congruence and patellar tilt angles), and complications were evaluated at final follow-up. The results were also compared with literature-reported outcomes of other surgical procedures for patellar dislocation. Results Twenty-five patients (mean age, 18.3 ± 4.8 years) were included in the study. The mean clinical follow-up period was 7.0 ± 2.5 (range, 3.8–12.2) years. The mean Kujala score was significantly improved from 54.7 ± 14.0 (range, 37–86) preoperatively to 91.0 ± 7.6 (range, 63–99) at a mean follow-up period of 7 years (P P P Conclusions Arthroscopy-controlled medial reefing and lateral release significantly improved the clinical and radiologic outcomes of the patients with recurrent patellar dislocation at a mean follow-up period of 7 years. The results of this study are comparable with the literature-reported outcomes of other surgical procedures for patellar dislocation. Level of evidence Level IV, retrospective therapeutic case series.

Purpose This double-blind, randomized, Phase III clinical trial was conducted to assess the efficacy and safety of the novel divinyl sulfone cross-linked hyaluronate (YYD302) compared with the 1,4-butanediol diglycidyl ether cross-linked hyaluronate (Synovian) in patients with knee osteoarthritis. Methods A total of 184 patients with osteoarthritis (Kellgren-Lawrence grade I–III) were randomized to 1 of 2 study groups (YYD302 group, n = 95; Synovian group, n = 89). A single injection of YYD302 or Synovian was given to both groups, and 182 participants completed the study (YYD302 group, n = 95; Synovian group, n = 87). The primary end point was the change in weight-bearing pain (WBP) at 12 weeks after the primary single injection. Secondary end points included the Knee Injury and Osteoarthritis Outcome Score; the Western Ontario and McMaster Universities Osteoarthritis Index score; the Patient Global Assessment and Investigator Global Assessment; the range of motion, swelling, and tenderness of the target knee; OMERACT-OARSI responder rate; WBP responder rate (the proportion of patients achieving at least 20 mm or 40% decrease in WBP); and rate of rescue medicine use and its total consumption at weeks 2, 4, and 12. Based on the efficacy results at week 12, the responders were administered an additional single injection of the same study drug at week 24, and safety and efficacy were additionally assessed at week 36. Findings Mean changes of WBP at 12 weeks after the primary injection were –31.76 mm with YYD302 and –29.74 mm with Synovian, proving noninferiority of the YYD302 group to the Synovian group as the lower bound of the 95% CI (–4.3 to 8.3) was well above the predefined margin (–10 mm). At week 2, the Knee Injury and Osteoarthritis Outcome Score (total, pain, activities of daily living, and sports/recreation) and Western Ontario and McMaster Universities Osteoarthritis Index scores (total, stiffness) were significantly better in the YYD302 group than in the Synovian group. There were no significant differences between the groups in all other end points. Local overall adverse events (pain, heat, erythema, or swelling) at the injection site were observed in 48.4% of the YYD302 group and in 47.7% of the Synovian group. No serious reactions were reported. There was no statistically significant difference between the 2 groups regarding re-injected patients (YYD302 group, n = 54; Synovian group, n = 46) in any of the efficacy outcomes at week 36. Implications The results of this study support that YYD302 is comparable to Synovian in terms of the efficacy and safety of the intra-articular injection treatment for osteoarthritis of the knee joint. Furthermore, YYD302 provided faster improvements in some efficacy assessments compared with Synovian. ClinicalTrials.gov identifier: NCT03561779.

This Letter proposes a stage-wise training method that uses block-wise retraining to transfer the useful knowledge of a pre-trained deep residual network (ResNet) in a teacher-student framework (TSF). To achieve this, flow-based hidden information transfer and hierarchically supervised retraining of the information are alternatively implemented from bottom to top between teacher and student ResNets in the TSF. To evaluate the effectiveness of the proposed method, the authors used well-known image data sets Canadian Institute For Advanced Research (CIFAR)-10, CIFAR-100, and street view house number. The results showed that the flow-based bottom-up knowledge transfer combined with incremental block-wise retraining can provide the improved small student ResNet with higher accuracy than the deep teacher ResNet. This approach will help extend the use of deep neural network models to limited computing environments.

The authors propose a new knowledge transfer method coupled with a generative adversarial network (GAN) when multiple-flow-based knowledge is considered in a teacher-student framework using a residual network (ResNet). In this method, several independent discriminators adapting multilayer-perceptron-based structures were designed for flow-based knowledge transfer. The proposed GAN-based optimisation alternatively updates the multiple discriminators and a student ResNet such that the flow-based features of the student ResNet are generated as closely as possible to the real features of a teacher ResNet. The experiments demonstrate that the student ResNet trained using the proposed method more accurately captures the distribution of the flow-based teacher knowledge than the l 2 -distance-based training method. In addition, the proposed method provided better classification accuracy than the existing GAN-based knowledge transfer method.

Purpose: To compare the clinical outcomes of the arthroscopic treatments for popliteal cysts with and without cystectomy. Methods: PubMed/MEDLINE, EMBASE, KoreaMed, and Cochrane Library were searched from the earliest available date of indexing through August 2016. The methodological quality of all articles was assessed according to the Coleman methodology score (CMS). Studies were grouped according to the surgical method, and a meta-analysis was conducted to identify the unsuccessful clinical outcome and complication rates. Results: Nine studies were included; the mean CMS was 67.33 (standard deviation, 8.75 points). Cystectomy was reported in five studies; cystectomy was not performed in four studies. The odds ratio of unsuccessful clinical outcomes evaluated by Rauschning and Lindgren score was 122.05 (p

This study aimed to evaluate the effect of the red (R)-to-blue (B) ratio of light on the growth and phenolic compounds of Crepidiastrum denticulatum under a phytochrome photostationary state (PSS) for growth in a plant factory with artificial light (PFAL) using light-emitting diodes (LEDs). Three-week-old C. denticulatum seedlings were transplanted into a PFAL where the air temperature, relative humidity, CO2 concentration, and light period were set at 20 °C, 60%, 1000 μmol·mol−1, and 16 h, respectively. Three controls were used with different ratios of R to B light without supplemental FR light: 8:2, 7:3, and 6:4 (based on chip number; 130 µmol·m−2·s−1 photosynthetic photon flux density). For the treatments, the same R to B light ratios as in the controls were used but supplemented with FR light, plus a treatment with only R light supplemented with FR, set to a PSS of 0.71. Growth characteristics and total phenolic and individual phenolic contents were measured after a 6-week treatment. When the R light ratio increased, shoot dry weight, leaf length, leaf width, and leaf area increased regardless of supplemental FR light, and the R8B2 with FR light treatment was the most effective, with significantly higher values (1.6–2 times) than the control. FR irradiation did not have any negative effect on total phenolic content, chlorogenic acid, caffeic acid, and chicoric acid per unit dry weight (g); thus, the R8B2 with FR treatment had significantly higher total phenolic and individual phenolic contents per shoot (43% and 52–62%, respectively). Thus, supplemental lighting with FR LEDs was found to be effective to enhance the growth and bioactive compounds of C. denticulatum in a PFAL installed with a R and B lighting system, and the effectiveness could be changed by the RB ratio, with 8:2 considered the proper ratio.

PURPOSE: We developed predictive models using different programming languages and different computing platforms for machine learning (ML) and deep learning (DL) that classify clinical diagnoses in patients with epiphora. We evaluated the diagnostic performance of these models. METHODS: Between January 2016 and September 2017, 250 patients with epiphora who underwent dacryocystography (DCG) and lacrimal scintigraphy (LS) were included in the study. We developed five different predictive models using ML tools, Python-based TensorFlow, R, and Microsoft Azure Machine Learning Studio (MAMLS). A total of 27 clinical characteristics and parameters including variables related to epiphora (VE) and variables related to dacryocystography (VDCG) were used as input data. Apart from this, we developed two predictive convolutional neural network (CNN) models for diagnosing LS images. We conducted this study using supervised learning. RESULTS: Among 500 eyes of 250 patients, 59 eyes had anatomical obstruction, 338 eyes had functional obstruction, and the remaining 103 eyes were normal. For the data set that excluded VE and VDCG, the test accuracies in Python-based TensorFlow, R, multiclass logistic regression in MAMLS, multiclass neural network in MAMLS, and nuclear medicine physician were 81.70%, 80.60%, 81.70%, 73.10%, and 80.60%, respectively. The test accuracies of CNN models in three-class classification diagnosis and binary classification diagnosis were 72.00% and 77.42%, respectively. CONCLUSIONS: ML-based predictive models using different programming languages and different computing platforms were useful for classifying clinical diagnoses in patients with epiphora and were similar to a clinician’s diagnostic ability. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13139-019-00574-1) contains supplementary material, which is available to authorized users.

We devise a layer‐wise hint training method to improve the existing hint‐based knowledge distillation (KD) training approach, which is employed for knowledge transfer in a teacher‐student framework using a residual network (ResNet). To achieve this objective, the proposed method first iteratively trains the student ResNet and incrementally employs hint‐based information extracted from the pretrained teacher ResNet containing several hint and guided layers. Next, typical softening factor‐based KD training is performed using the previously estimated hint‐based information. We compare the recognition accuracy of the proposed approach with that of KD training without hints, hint‐based KD training, and ResNet‐based layer‐wise pretraining using reliable datasets, including CIFAR‐10, CIFAR‐100, and MNIST. When using the selected multiple hint‐based information items and their layer‐wise transfer in the proposed method, the trained student ResNet more accurately reflects the pretrained teacher ResNet's rich information than the baseline training methods, for all the benchmark datasets we consider in this study.

Background: Little is known about the threshold of patient-reported outcomes (PROs) at which patients perceive to have attained a substantial clinical benefit (SCB) after anterior cruciate ligament reconstruction (ACLR). Purpose: To determine the SCB value of PROs 1 year after ACLR in the general population and to determine factors that predict SCB attainment. Study Design: Case series; Level of evidence, 4. Methods: The Lysholm, International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC-SKF), Tegner, and Anterior Cruciate Ligament–Return to Sport after Injury (ACL-RSI) scores were examined postoperatively in 88 patients who underwent ACLR. At the 12-month follow-up visit, the patients answered 2 independent anchor questions about daily discomfort and functional recovery. Receiver operating characteristic (ROC) curve analysis was used to differentiate PRO scores between patients who responded as having no difficulty versus some difficulty with daily knee discomfort (anchor question 1) and between patients with substantial recovery versus nonsubstantial recovery of knee function (anchor question 2). The area under the ROC curve (AUC) was calculated to assess reliability, and the differences between the AUC values were compared. Multivariate logistic regression analyses were performed to determine predictors affecting SCB attainment. Results: There were 76 patients enrolled in this study. The 12-month Lysholm, IKDC-SKF, Tegner, and ACL-RSI scores that corresponded to the SCB were 88.0, 85.1, 6.5, and 64.2 for anchor question 1 and 84.5, 77.7, 5.5, and 57.1 for anchor question 2, respectively. The AUC values obtained from the ROC curve analyses showed acceptable to excellent reliability (anchor question 1: Lysholm, 0.90; IKDC-SKF, 0.86; Tegner, 0.71; ACL-RSI, 0.92; anchor question 2: Lysholm, 0.80; IKDC-SKF, 0.90; Tegner, 0.82; ACL-RSI, 0.82) and were all statistically significant ( P < .001 to P = .028). For all PROs, younger age (Odds Ratio (OR), 0.88-0.94; P < .001 to P = .027) and greater muscle strength (OR, 1.03-1.07; P < .001 to P = .023) were predictive factors of SCB attainment. Conclusion: The postoperative Lysholm, IKDC-SKF, Tegner, and ACL-RSI scores showed acceptable to excellent reliability in predicting the SCB after ACLR in the general population. Age at surgery and thigh muscle strength influenced SCB attainment for all PROs.

The bistatic configuration used for inverse synthetic aperture radar (ISAR) imaging has attracted considerable attention because of its potential for overcoming certain monostatic ISAR imaging limitations. However, translational motion compensation (TMC) and rotational motion compensation (RMC) are the most fundamental requirements for both bistatic ISAR (Bi-ISAR) and monostatic ISAR imaging to obtain the high levels of image resolution desired. Moreover, range and cross-range scaling (RCRS) and bistatic distortion correction (BDC) are essential functionalities for the efficient use of Bi-ISAR images in applications. In this paper, a novel approach to sparse aperture (SA) Bi-ISAR imaging is presented for simultaneously performing TMC, RMC, RCRS, and BDC on maneuvering targets based on compressive sensing. Instead of solving conventional optimization problems constrained by the sparsity of the signals, the proposed method utilizes sensing matrix estimation technique for Bi-ISAR image reconstruction using parametric signal model reconstruction by looking for the basis functions that best represent the behavior of sensing dictionary matrix comprised of the observed SA data. The reconstruction of the sensing matrix is based on a modified orthogonal matching pursuit (MOMP)-type basis function-searching scheme. Finally, we generate a focused and scaled Bi-ISAR image from the complete Bi-ISAR signal recovered using the proposed method. Several simulation results reveals that the proposed method is very efficient in forming Bi-ISAR images of high-speed maneuvering targets in terms of the Bi-ISAR signal reconstruction accuracy.

A one-way valve lesion plays an important role in the formation of Baker’s cysts and serves as an important landmark for accessing these cysts during arthroscopic surgery. This study aimed to investigate the incidence of one-way valve lesions and their effect on clinical outcomes in patients who underwent arthroscopic cystectomy for Baker’s cysts. Patients who underwent arthroscopic cystectomy for Baker’s cysts between June 2005 and November 2017 were retrospectively reviewed. Patient demographic characteristics, radiologic/arthroscopic findings (presence of one-way valve lesions, concurrent chondral and meniscal lesions, and cyst wall thickness), and clinical outcomes (clinical recurrence rate, Lysholm score, and complications) at the 2-year follow-up were evaluated. Subgroup analysis was performed to compare clinical outcomes between patients with and without one-way valve lesions. Thirty patients (mean age, 57.4 ± 9.4 years) were included in this study. One-way valve lesions were surgically documented in 11 patients (36.7%). Ten patients (33.3%) had chondral lesions with an International Cartilage Repair Society grade ≥ 3, and 23 patients (76.7%) had concurrent chondral and meniscal lesions. At the 2-year follow-up, none of the patients had experienced clinical recurrence; the mean Lysholm score was 76.3 ± 17.5 (48–100). Three patients reported persistent pain, while two reported numbness or paresthesia. Subgroup analysis showed no significant differences in clinical recurrence rates, Lysholm scores, and complication rates between the groups. The incidence of one-way valve lesions during arthroscopic cystectomy for Baker’s cysts was lower than that previously reported. Arthroscopic cystectomy showed good clinical results in patients with and without these lesions.

Meniscal tears are common injuries that may result in pain and functional limitation. Treatment options include benign neglect, rehabilitation, meniscectomy, and repair. Nonsurgical care can be used for older patients with degenerative meniscal pathology. Meniscectomy remains a viable and successful intervention for pain relief and functional improvement for symptomatic meniscal tears in appropriately indicated patients. However, it results in an increase in contact stresses in the articular cartilage of the affected compartment, leading to osteoarthritis. Meniscus repair provides improved long-term outcomes, better clinical outcomes, and less degenerative changes compared with meniscectomy. Orthopedic surgeons should know the proper indications of meniscus repair and understand various techniques and surgical devices for the management of repairable meniscal tears. A new technology of biologic augmentation for better healing and tissue engineering for meniscal defect is currently developing, and they may help the management of complex meniscal tears in the future.

Medical image diagnosis should consider the information contained in multiple images, not just a single image, such as natural image classification. Mammography is the most basic X-ray screening method for diagnosing breast cancer, and mammograms have four images per patient. Convolutional neural networks should be able to diagnose using these four images. This paper proposes a convolutional neural network to simultaneously concatenate four images to solve the multi-view problem. The proposed network was trained and validated with the digital database for screening mammography (DDSM) and achieved 0.952 area under the ROC curve (AUC) for the two-class problem (positive vs. negative). This paper also proposes a new approach to localize lesions without patch labels or mask labels.

We propose a new teacher–student framework (TSF)-based knowledge transfer method, in which knowledge in the form of dense flow across layers is distilled from a pre-trained “teacher” deep neural network (DNN) and transferred to another “student” DNN. In the case of distilled knowledge, multiple overlapped flow-based items of information from the pre-trained teacher DNN are densely extracted across layers. Transference of the densely extracted teacher information is then achieved in the TSF using repetitive sequential training from bottom to top between the teacher and student DNN models. In other words, to efficiently transmit extracted useful teacher information to the student DNN, we perform bottom-up step-by-step transfer of densely distilled knowledge. The performance of the proposed method in terms of image classification accuracy and fast optimization is compared with those of existing TSF-based knowledge transfer methods for application to reliable image datasets, including CIFAR-10, CIFAR-100, MNIST, and SVHN. When the dense flow-based sequential knowledge transfer scheme is employed in the TSF, the trained student ResNet more accurately reflects the rich information of the pre-trained teacher ResNet and exhibits superior accuracy to the existing TSF-based knowledge transfer methods for all benchmark datasets considered in this study.

Background: Insufficient data are available to support the routine use of tranexamic acid (TXA) in anterior cruciate ligament (ACL) surgeries with respect to administration method and frequency, exposure duration, dose, and adverse effects. Purpose: To investigate whether intra-articular (IA) administration of TXA could reduce hemarthrosis and postoperative pain in patients after ACL reconstruction. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: A total of 47 patients were included in this study, which was performed between July 2017 and May 2019. Single-bundle reconstructions using autologous hamstring tendon grafts were performed in all patients. The patients were randomized into 2 groups: the TXA group (received the index procedure with 100-mL IA injection of TXA [30 mg/mL]) and a control group (did not receive IA injection of TXA). No patients received a drain. Blood loss was calculated on the basis of hemoglobin balance at postoperative day (PD) 2. The visual analog scale (VAS) for pain score was assessed at PD 3. The midpatellar circumference was measured at PD 2 and PD 5. Knee range of motion (ROM) was evaluated 6 weeks after surgery. Results: The mean ± SD blood loss was 467 ± 242 mL in the TXA group and 558 ± 236 mL in the control group. No significant differences were found for blood loss ( P = .20), VAS pain scores ( P = .28), ROM at postoperative week 6 ( P = .61), or patellar circumference at PD 2 ( P = .75) and PD 5 ( P = .84). Conclusion: This study showed that IA administration of 3.0 g of TXA had no effect in reducing blood loss and postoperative pain after primary anatomic single-bundle ACL reconstruction using quadruple hamstring autografts. Registration: NCT04042688 ( ClinicalTrials.gov identifier).

In this study, we propose an efficient strategy to exploit cross-range resolutions (CRRs) of inverse synthetic aperture radar (ISAR) images to improve classification performance. The proposed method preprocesses an ISAR image of an unknown target using both the CRR of an unknown ISAR image, which can be obtained using the cross-range scaling algorithm, and that of the ISAR images in a training database (DB). Specifically, the proposed method adjusts the unknown ISAR image so that the CRR of the adjusted unknown ISAR image is identical to that of the ISAR images in the training DB. The adjusted unknown ISAR image is then directly used for the subsequent classification task, thus considerably improving classification performance.

Purpose This study was conducted to investigate the outcomes of bearing exchange for the treatment of mobile bearing dislocation in medial unicompartmental knee arthroplasty (UKA). Materials and Methods We retrospectively reviewed 18 patients (15 females and 3 males, mean age of 65 years) treated with bearing exchange following mobile bearing dislocation in medial UKA. The occurrence of bearing redislocation, the Oxford Knee Score, and radiographic changes at the last follow-up were investigated. Results Bearing redislocation after bearing exchange occurred in 9 of 18 patients (50%). Of these 9 patients, 7 underwent conversion to total knee arthroplasty after bearing redislocation. The 9 patients without bearing redislocation showed good to excellent clinical outcomes at a mean follow-up of 55 months after bearing exchange. The non-redislocation group had a higher percentage of posterior dislocation of the bearing than the redislocation group (55.5% vs. 22.2%, p=0.040). Univariate logistic regression analysis showed no significant risk factors for bearing redislocation. Conclusions This study showed a high rate of bearing redislocation after isolated, mobile bearing exchange for bearing dislocation following medial UKA. Therefore, bearing exchange as a sole treatment should be carefully considered in selected patients with correctable causes of bearing dislocation.

As there were few previous studies with a small number of subjects, the purpose of this was to evaluate the prognostic significance of 18F-FDG PET/CT in patients with distal bile duct cancer undergoing curative surgery. The study included 40 patients (M/F = 24:16; age 68.0 ± 8.0 years) who underwent preoperative 18F-FDG PET/CT followed by curative surgical resection. The participant’s age, sex, Eastern Cooperative Oncology Group performance-status score, baseline serum CA 19-9 level, stage, pathologic T and N stages, tumor size, tumor grade, tumor growth pattern, R0 resection, and adjuvant therapy were included as clinicopathological variables for predicting overall survival. The PET variables were maximum standardized uptake value (SUVmax), average SUV (SUVavg), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the tumor. The Kaplan-Meyer method and Cox proportional hazards model were used for the survival analysis. A total of 15 of 40 patients (37.5%) died during the follow-up period. In univariate analysis, low SUVmax (≤ 2.7, p = 0.0005) and low SUVavg (≤ 2.6, p = 0.0034) were significant predictors of poor overall survival. In multivariate analyses, only low SUVmax (HR = 6.7016, 95% CI 1.9961–22.4993, p = 0.0047) was an independent prognostic factor associated with poor overall survival. The SUVmax of the primary tumor measured by 18F-FDG PET/CT was an independent significant prognostic factor for overall survival in patients with distal bile duct cancer. However, different results from a previous study warrant further large sample-sized study.

The purpose of this study was to investigate whether the location of the hinge affects the incidence of hinge fracture during medial closing-wedge distal femoral varus osteotomy (DFVO). Twenty knees from 10 fresh-frozen human cadavers (mean age, 75 ± 17 years) were used to perform uniplanar medial closing-wedge DFVO with a 7-mm wedge. Each specimen was randomly assigned to either group A (supracondylar hinge) or group B (lateral condylar hinge). The incidence of hinge fracture and stability was compared between both groups after uniplanar medial closing-wedge DFVO. In group A, 8 of 10 knees had a lateral cortex fracture during closure of the osteotomy gap, and all fractured knees were unstable. Two knees with an intact lateral cortical hinge showed stability under manual valgus and varus forces. After intentional breakage of the lateral cortical hinge, both knees were found to be unstable under the same force. In group B, 2 of 10 knees had a lateral cortex fracture, and 8 knees had no fractures. All specimens were found to be stable under manual valgus and varus forces. After intentional breakage of the lateral cortical hinge in group B, 2 knees were unstable, while 8 knees remained stable. This study showed a significantly higher incidence of lateral cortical hinge fracture and instability in group A than in group B during closure of the osteotomy gap.

This study aims to develop a safety analysis methodology through which the integrity of both the lower head and the in-core instrumentation (ICI) nozzles of an external vessel-cooling reactor in nuclear power plants can be verified through finite element analyses. The ICI was used to measure the neutron flux distribution and control in the core of the reactor. Two analysis models were implemented. One was a two-dimensional model for the lower head, and the other was a three-dimensional model for the ICI nozzle. Heat transfer and thermo-mechanical analyses were also performed. The heat transfer analysis was conducted to evaluate the heat flux caused by the high-temperature melt and the conditions caused by external vessel cooling. The thermo-mechanical analysis was performed by using thermal loading, internal pressure, and deadweight of debris. Consequently, an ejection caused by the failure of the weld zone between the nozzle and the lower head was verified. An additional analysis of the nozzle support parts was then performed. The analysis results revealed that both nozzle ejection and contaminant leakage could be prevented if the nozzle support parts have enough stiffness.

In this paper, we introduce a bistatic inverse synthetic aperture radar (Bi-ISAR) cross-range scaling (CRS) method to more effectively use Bi-ISAR images in their applications. For this, we propose a method to estimate the effective rotation velocity of a target in a Bi-ISAR imaging system, and restore a linear-geometry distortion that yields a sheared shape of Bi-ISAR images. In the simulations, we observed that our proposed method is capable of performing robust and precise Bi-ISAR CRS.

A new instrument system has been introduced to improve the accuracy and reproducibility of implant positioning in Oxford® unicompartmental knee arthroplasty (UKA). This study aimed to determine if the new instrumentation could improve postoperative implant positioning and limb alignment, and reduce the occurrence of outliers in Oxford® UKA.A total of 77 cases of Oxford® UKA with the new instrumentation were included. Individual matching for the conventional instrument group was performed according to age, sex, and body mass index. Postoperative radiological variables, including the hip-knee-ankle angle and the varus/valgus and flexion/extension angles of the femoral and tibial implants, were measured and compared between the new instrumentation group and the conventional group. The outliers in implant positions and postoperative complications were also compared.No significant between-group differences were observed in terms of lower limb alignment and tibial implant alignment. However, statistically significant differences were identified in the varus/valgus and flexion/extension angles of the femoral implant (P=0.01 and P0.001, respectively). More outliers were observed in the flexion/extension angles of the femoral and tibial implants in the new instrumentation group. Eight meniscal bearing dislocations and three lateral compartmental degenerative changes were found in the conventional group, while there were two meniscal bearing dislocations in the new instrumentation group during the study period.The present study did not confirm any benefit of the new instrument system in terms of postoperative limb alignment, positioning of the implant, or reducing outliers beyond the use of the conventional instruments.

In this paper, we propose a new and efficient inverse synthetic aperture radar (ISAR) autofocus technique by introducing eigenimages to boost the speed of the traditional autofocus algorithms. First, a preprocessing step is applied to mitigate the noise components in the received data. Then, we perform an eigen-decomposition of the covariance matrix of the range-aligned data, and generate the signal eigenimage obtained by deriving the Fourier transform of a small number of eigenvectors corresponding to the dominant eigenvalues. Finally, traditional autofocus methods are combined with the proposed signal eigenimage rather than the original ISAR image to eliminate image blurring due to phase errors. The proposed method can significantly lower the computational complexity of the traditional autofocus methods because the dimensionality of the signal eigenimage is considerably smaller than that of the ISAR image. Despite the low dimensionality of the signal eigenimages, the proposed scheme provides well-focused ISAR images that are comparable to those of the traditional autofocus methods in terms of image focal quality. Several simulations and experimental results using measured data of an actual flying aircraft are presented to verify the effectiveness of the proposed method.

Inverse synthetic aperture radar (ISAR) is a coherent imaging system formed by conducting signal processing on the received data consisting of radar cross section reflected from a maneuvering target. Autofocus is an essential step of ISAR imaging, whose performance has a great influence on the quality of the radar image. Minimum Shannon entropy phase adjustment (MSEPA) and minimum Renyi entropy-based algorithm (MREA) have been widely used to compensate for the phase error in ISAR autofocus. However, MSEPA and MREA have some drawbacks in terms of the noise sensitivity and computational efficiency. Tsallis entropy (nonextensive entropy) is a useful measure to describe the thermostatistical properties of physical systems. This paper concentrates on the performance of minimum Tsallis entropy phase adjustment (MTEPA) instead of the Shannon entropy. By minimizing the Tsallis entropy of an ISAR image, the MTEPA can significantly improve the computational efficiency, while retaining the image focal quality of the restored ISAR images, as compared to MSEPA and MREA. The order q of Tsallis entropy can be experimentally found by analyzing both an image quality metric and the computation time. In experimental results, the effectiveness of the MTEPA is illustrated and analyzed with simulated targets consisting of point scatterers and measured Boeing-747 data.

The Weinberg converter is a suitable choice for the battery discharge regulator of a geostationary satellite due to its high efficiency, continuous input and output current, and soft switching of switches and diodes. Nevertheless, this converter has high output current ripple during the commutation period of its output diodes. Therefore, the output RMS current and output voltage ripple are high, which may directly affect the lifetime and total capacitance of bus capacitors and hence, the lifetime and volume of the geostationary satellite. Thus, reducing the output current ripple is important to the design of the geostationary satellite. An improved Weinberg converter with an additional inductor and capacitor is proposed in this paper to reduce the output current and voltage ripple. It features soft switching of all switches, no reverse recovery problems of the diodes, and reduced magnetizing offset current in the coupled inductor. The proposed converter is verified with experimental results from a 750W, 100kHz, 36-50Vdc prototype.

Purposes The purpose of this study is to review the use of an allograft or autograft in medial patellofemoral ligament (MPFL) reconstruction. Materials and methods Various electronic databases were searched for relevant articles published from January 2000 to September 2017 that evaluated clinical outcomes of MPFL reconstruction using an autograft or allograft. Data search, extraction, analysis, and quality assessments were performed based on Cochrane Collaboration guidelines. Results The study of 21 autografts and one allograft was included in this review. Although direct comparative studies were unavailable, the Kujala score and subjective results were reported in the majority of these studies. While the use of an autograft for MPFL reconstruction yielded satisfactory clinical outcomes with few perioperative complications, no new outcome has been drawn from the use of allografts. Conclusions Although many studies have shown favorable clinical results for MPFL reconstruction using an autograft, the clinical results of MPFL reconstruction using an allograft have not yet been sufficient to achieve meaningful clinical results due to low levels of evidence. Direct comparisons were not conducted because there were very few studies on allografts; thus, further research in this area should be performed in the future. Electronic supplementary material The online version of this article (10.1186/s43019-019-0008-0) contains supplementary material, which is available to authorized users.

Recent advances in computing power made possible by developments of faster general-purpose graphics processing units (GPGPUs) have increased the complexity of convolutional neural network (CNN) models. However, because of the limited applications of the existing GPGPUs, CNN accelerators are becoming more important. The current accelerators focus on improvement in memory scheduling and architectures. Thus, the number of multiplier-accumulator (MAC) operations is not reduced. In this study, a new convolution layer operation algorithm is proposed using the coarse-to-fine method instead of hardware or architecture approaches. This algorithm is shown to reduce the MAC operations by 33%. However, the accuracy of the Top 1 is decreased only by 3% and the Top 5 only by 1%.

Background: There is limited information about the functional recovery and rate of return to preinjury levels of sports among recreational athletes after anterior cruciate ligament reconstruction (ACLR). Purpose: To investigate the recovery of quadriceps or hamstring strength, assess functional performance, and determine the rate of return to preinjury sports levels among recreational athletes at 1 year after ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 91 recreational-level athletes who underwent anatomic single-bundle ACLR were enrolled. We evaluated the limb symmetry index (LSI) of the quadriceps and hamstring peak torque strength at 60°, in addition to hop test performance (single-leg, triple, crossover, and 6-m timed), patient-reported outcomes, and pre- versus postoperative Tegner activity levels. Outcomes were compared between younger (age Results: There were 48 patients in the younger group and 43 patients in the older group. At 1-year follow-up, the overall LSIs for quadriceps strength and hamstring strength were 77% and 86%, respectively, and the LSIs of the hop tests were 79% for single-leg, 81% for triple, 84% for crossover, and 85% for 6-m timed hop. Overall, only 24% patients returned to their preinjury Tegner level, and only 8% of patients met the criteria for return to pivoting, cutting, and jumping sports. At 1-year follow-up, the younger group showed significantly more quadriceps strength than the older group (85% vs 64%; P = .0001), better single, triple, crossover, and 6-m timed hop test results (85% vs 69%, P = .003; 84% vs 75%, P = .046; 91% vs. 74%, P < .001; and 91% vs 76%, P = .003, respectively), higher Lysholm score (87 vs 74; P < 0.001) and International Knee Document Committee score (82 vs 66; P < .001), and a higher rate of return to preinjury Tegner level (35% vs 12%; P = .009). Conclusion: Only 24% of patients returned to the preinjury Tegner level at 1 year after ACLR (35% younger group vs 12% older group; P = .009). This information might be helpful in setting realistic expectations for recreational athletes after surgery.

Particle swarm optimization coupled with exhaustive search method (PSO-ESM) is proposed for inverse synthetic aperture radar cross-range scaling (CRS). Robust scatterers against angular scintillation are extracted using scale-invariant feature transform, and locations of the extracted scatterers are applied to PSO-ESM that estimate not only rotation center (RC), but also rotation velocity (RV). In simulations, it was observed that PSO-ESM can perform robust CRS owing to the joint estimation of RC and RV.