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Abstract Background The cartilage quality of the lateral compartment needs to be clarified prior to medial unicompartmental knee arthroplasty (UKA). Valgus stress radiograph has been recommended as the preferred tool. Some studies also show that magnetic resonance imaging (MRI) has a higher diagnostic value. So, we conducted this study to compare whether valgus stress radiographic lateral joint space width (LJSW) and MRI grading can accurately reflect cartilage quality and its screening value for UKA-suitable patients. Methods One hundred and thirty eight knees proposed for UKA were enrolled prospectively. Valgus stress radiograph was taken to measure LJSW. LJSW > 4 mm was considered normal and suitable for UKA. For weight-bearing area cartilage of lateral femoral condyle, Recht grade was assessed by MRI preoperatively. Recht grades ≤ 2 were treated as non-high-grade injuries while Recht grades > 2 were treated as high-grade injuries. Outerbridge grade was the gold standard and was assessed intraoperatively. Patients with Outerbridge grades 0–2 (non-high-grade injuries) underwent UKA, and patients with Outerbridge grades 3–4 (high-grade injuries) underwent total knee arthroplasty (TKA). The diagnostic parameters of valgus stress radiograph and MRI for the selection of UKA candidates were calculated, and receiver operating characteristic curves were drawn. P

Objective Finding reliable tools to predict alignment change after medial mobile‐bearing unicompartmental knee arthroplasty (UKA) can help surgeons avoid under‐ or over‐correction. This prospective study aimed to investigate whether the parameters related to medial collateral ligament tension on valgus stress radiograph can predict the alignment change of medial mobile‐bearing UKA and establish a prediction model. Methods This study prospectively included the patients undergoing medial mobile‐bearing UKA for knee osteoarthritis from November 2018 and April 2021. Patients took valgus stress radiograph and MRI preoperatively and took full‐length weight‐bearing anterior–posterior radiograph of the lower extremity preoperatively and postoperatively. The medial joint space width (MJSW) on valgus stress radiograph, area of femoral and tibial osteophyte on MRI, medial extrusion distance (MED) of the meniscus on MRI, and the change in hip‐knee‐ankle angle (∆HKAA) were measured. Factors influencing ∆HKAA were analyzed by correlation analysis. Univariable and multivariable linear regression analysis was performed to establish a prediction model of ∆HKAA. Results One hundred and seven knees were included. On average, the preoperative HKAA was 170.84° ± 3.73°, and UKA corrected the alignment to 175.16° ± 3.21° postoperatively (p

Abstract Background Leg length change after knee arthroplasty is one of the most concerned problems for patients and doctors. However, as there was only one literture focused on the leg length change after unicompartmental knee arthroplasty, we aimed to clarify the leg length change after medial mobile-bearing unicompartmental knee arthroplasty (MOUKA) using a novel double calibration method. Methods We enrolled patients who underwent MOUKA and had taken full-length radiographs in a standing position prior to and at 3 months after the operation. We eliminated the magnification by a calibrator and corrected the longitudinal splicing error by measuring the femur and tibia lengths before and after operation. Perceived leg length change was collected 3 months after operation. Bearing thickness, preoperative joint line convergence angle, preoperative and postoperative varus angles, flexion contracture and Oxford knee score (OKS) were also collected. Results From June 2021 to February 2022, 87 patients were enrolled.76 (87.4%) of them showed an increase with an average of 0.32 cm (range from -0.30 cm to 1.05 cm) in leg length change. The lengthening was strongly correlated with the degree of varus deformity and its correction value (r = 0.81&0.92, P

Abstract The lithium niobate on insulator (LNOI) platform has revolutionized lithium niobate materials, and a series of quantum photonic chips have exhibited unprecedented performances. Quantum frequency conversion (QFC) that enables quantum state preservation during frequency conversion is crucial in quantum technology. This work demonstrates a low-noise QFC process on the LNOI nanophotonic platform, connecting telecom and near-visible bands. An internal conversion efficiency of 73% and an on-chip noise count of 900 counts per second (cps) are achieved. Furthermore, the preservation of quantum statistical properties is verified, indicating the QFC chip’s promise for extensive applications of LNOI integrated circuits in quantum information. Based on this chip, we constructed an upconversion single-photon detector with a detection efficiency of 8.7% and a noise of 300 cps, paving the way to integrated on-chip single-photon detection. The realization of a low-noise QFC device also provide a pathway for practical chip-scale QFC-based quantum systems in heterogeneous configurations.

Abstract Background Many patients following unicompartmental knee arthroplasty (UKA) also suffer from diabetes mellitus, which may lead to an increased likelihood of postoperative deep venous thrombosis (DVT). Therefore, we evaluated whether DVT incidence would increase 3 days following UKA in diabetic patients. Methods Patients who underwent UKA from August 2018 to September 2021 in our hospital were retrospectively included. Age, gender, body mass index, hypertension, mode of anesthesia, surgery time, intraoperative blood loss, tourniquet pressure and time, and glycosylated hemoglobin concentration were recorded as confounders. We compared the incidence and type of DVT between non-diabetic and diabetic patients and evaluated the effect of glycosylated hemoglobin levels on DVT. Results Of all the 224 patients, 96 had diabetes and 128 did not. Within 3 days after surgery, DVT occurred in 25 cases in the diabetic group and 17 cases in the non-diabetic group (p

BackgroundThe incidence of periprosthetic fractures after total knee arthroplasty (TKA) increases in parallel with the number of procedures. Comminuted fractures along the primary fracture line extending to the edge of the prosthesis are challenging, and bilateral fractures are rarely reported, especially with open injuries.Case presentationA 65-year-old female had undergone bilateral TKA in our hospital 5 years before admission. She was admitted with a traumatic bilateral Rorabeck type II B distal femur periprosthetic fracture (closed right, open left, Gustilo II) and was treated with bilateral staged open reduction and internal fixation (ORIF) with double-locking plates. The patient experienced a prolonged delayed fracture union and finally healed around 21 months postoperatively. The function was satisfactory after 4 years of follow-up.ConclusionORIF with double-locking plates can be used to treat Rorabeck II B periprosthetic fracture where the primary fracture line extends beyond the edge of the prosthesis; however, there may be delayed healing or nonunion. Patients need to undergo long-term rehabilitation and endure long disability times and require good rehabilitation nursing care. Once they achieve bone healing, the treatment achieves bone preservation and substantial prosthesis survival.

Abstract Background Hybrid Oxford unicompartmental knee arthroplasty (OUKA) consists of cementless femoral prostheses and cemented tibial prostheses. Although a hybrid OUKA has been used in clinical practice, the clinical outcome has not been reported. The purpose of this study was to compare the short-term clinical outcomes and rate of residual bone cement extrusion between hybrid and cemented prostheses and analyse the possible reasons for differences between outcomes. Methods A total of 128 knees (118 patients) with end-stage osteoarthritis were included in this study, of which underwent consecutive operations using unicondylar Oxford phase 3 implants from July 2017 and September 2019 in our centre. Follow-up was performed at 6 weeks, 3 and 6 months, 1 year and every year after operation, and complications and changes in the Oxford knee score (OKS) were recorded. The OKS of the two groups was analysed by the generalized estimating equation approach. Prosthesis-based standard fluoroscopy was performed in a timely manner after each operation, and the rate of residual cement extrusion of the two groups was estimated using T-tests and a multivariate regression analysis. Results Excluding the cases that lost follow-up, a total of 120 knees (65 in hybrid group and 55 in cemented group) were included in the analysis. There was no statistically significant difference in patient characteristics between the two groups (p > 0.05). The average follow-up time was 23.4 months (and ranged from 12 to 38 months). As of the last follow-up, there were no complications, such as dislocation, fracture, prosthesis loosening and subsidence, but one patient in the cemented group experienced symptoms caused by residual loose cement. Postoperative OKS in both groups improved significantly (p < 0.001). There was no significant difference in the OKS at any point during the follow-up or in the improvement of the OKS between the two groups (p > 0.05). Residual cement was mainly extruded behind the tibial prosthesis. The rate of hybrid periprosthetic residual cement extrusion was significantly lower in the hybrid group than in the cemented group, and the difference was statistically significant (OR = 3.38; p = 0.014). Conclusions Hybrid OUKA is as effective as cemented OUKA in the short term after operation and can significantly reduce the residual cement extrusion rate around the tibial prosthesis.

Abstract Background High fever, knee swelling and pain after knee arthroplasty are often considered as symptoms of acute prosthetic joint infection. However, similar symptoms can also present as primary manifestations of adult-onset Still’s disease, which creates some interference in differential diagnosis. To our knowledge, this is the first published case of misdiagnosis of adult Still’s disease after total knee arthroplasty, who was initially misdiagnosed as an prosthetic joint infection due to the above-mentioned symptoms. The symptoms of the knee infection was not relieve after several revisions and continous antibiotic treatment. Finally, after several consultations and repeated evaluation it was diagnosed as adult-onset Still’s disease. Case presentation A 77-year-old female who underwent bilateral total knee arthroplasty 6 years ago was admitted to our hospital with high fever, right knee effusion and painful knee. Based on the results of joint fluid aspiration and culture, we treated the right knee as acute hematogenous prosthetic joint infection. After three debridement and revision surgeries, the patient’s symptoms continued to persist. Subsequent manifestations of other symptoms such as typical rash and sore throat and laboratory examination suggested the possibility of adult-onset Still’s disease. So she underwent diagnostic steroid hormone therapy at the recommendation of a rheumatologist, and a final revision was performed after symptom was controlled. At the one-year follow-up, the patient’s symptoms completely resolved and the knee revision was functioning well. Conclusions When joint swelling and pain occurs after knee arthroplasty, the possibility of joint infection should not only be considered, but rheumatic autoimmune diseases should also be differentiated. Because the manifestations of joint infection and rheumatic immune disease sometimes overlap highly, when reasonable treatment over a period of time fails to relieve symptoms and signs, we should notice subtle differences in symptoms and laborotary tests and look for other diagnostic possibilities in time.

Abstract Background High tibial osteotomy (HTO) has a history of nearly 60 years and has been widely used in clinical practice. Biplanar open wedge high tibial osteotomy (BOWHTO), which evolved from HTO, is an important therapy for the knee osteoarthritis. In our previous research, we found that the decrease of hemoglobin levels after high tibial osteotomy ranges from between 17 to 41 g/L, but this is highly inconsistent with the intraoperative bleeding and postoperative drainage observed in clinical practice. The purpose of this study was to investigate the perioperative hidden blood loss (HBL) after biplanar open wedge high tibial osteotomy (BOWHTO), as well as to study the effect of the actual correction angle on blood loss. Methods A retrospective analysis was performed on 21 patients who underwent BOWHTO for osteoarthritis of the knee due to proximal tibia deformity. Gross equation was used to calculate the perioperative total blood loss (TBL) and HBL. The actual correction angle was measured by postoperative anteroposterior radiograph. The correlation between HBL and correction angle was determined through correlation analysis. Results The TBL was 823.5 ± 348.7 mL and the HBL was 601.6 ± 297.3 mL, total hemoglobin loss was 25.0 ± 10.7 g/L, and the mean HBL/patient’s blood volume (H/P) was 13.19 ± 5.56% for 21 patients. The correlation coefficient of correction angle and H/P is statistically significant (|r| = 0.678, P = 0.001). Conclusions The actual total blood loss after BOWHTO was significantly higher than the observed, and the HBL was objective existent after BOWHTO. The proportion of H/P is positively correlated with the correction angle.

Uncertainty analysis of a time-varying ensemble vector field is a challenging topic in geoscience. Due to the complex data structure, the uncertainty of a time-varying ensemble vector field is hard to quantify and analyze. Measuring the differences between pathlines is an effective way to compute the uncertainty. However, existing metrics are not accurate enough or are sensitive to outliers; thus, a comprehensive tool for the further analysis of the uncertainty of transport patterns is required. In this paper, we propose a novel framework for quantifying and analyzing the uncertainty of an ensemble vector field. Based on the classical edit distance on real sequence (EDR) method, a robust and accurate metric was proposed to measure the pathline uncertainty. Considering the spatial continuity, we computed the transport variance of the neighborhood of a location, and evaluated the uncertainty correlation between each location and its neighborhood by using the local Moran’s I. Based on the proposed uncertainty measurements, a visual analysis system called UP-Vis (uncertainty pathline visualization) was developed to interactively explore the uncertainty. It provides an overview of the uncertainty and supports detailed exploration of transport patterns at a selected location, and allows for the comparison of transport patterns between a location and its neighborhood. Through pathline clustering, the major trends of the ensemble pathline at a location were extracted. Moreover, a glyph was designed to intuitively display the transport direction and diverging degree of each cluster. For the uncertainty analysis of the neighborhood, a comparison view was designed to compare the transport patterns between a location and its neighborhood in detail. A synthetic data set and weather simulation data set were used in our experiments. The evaluation and case studies demonstrated that the proposed framework can measure the uncertainty effectively and help users to comprehensively explore uncertainty transport patterns.