Biphasic Scaffold Loaded With Autologous Cartilage Yields Better Clinical Outcome and Magnetic Resonance Imaging Filling Compared With Marrow Stimulation for Focal Osteochondral Lesions in the Knee.

PURPOSE: To evaluate the effectiveness of marrow stimulation (MS) versus biphasic scaffold loaded with autologous cartilage (scaffold) in treating focal osteochondral lesions of the knee. METHODS: In total, 54 patients with symptomatic focal chondral or osteochondral lesion in the knee were randomized to either the scaffold group or the MS group. International Knee Documentation Committee subjective score, the Knee Injury Osteoarthritis Outcome Score, and magnetic resonance imaging (MRI) were assessed preoperatively and at 1 and 2 years after operation to compare treatment outcomes. Biopsy and second-look arthroscopy were performed at 1 year postoperatively for consenting patients. RESULTS: There were 27 patients (mean age 31.33 ± 10.95 years) in the scaffold group, and 27 patients (31.74 ± 11.44) in the MS group. The scaffold group and the MS group both included 23 patients with lesions ≤12.5 × 12.5 mm2 mm in size. In addition, each group had 4 patients with lesions between than 12.5 × 12.5 mm2 and ≤12.5 × 25 mm2. Both interventions achieved significant improvement in clinical outcome scores at 2 years. The scaffold group had greater International Knee Documentation Committee score than the MS group at 2 years (93.85 ± 9.55 vs 92.11 ± 9.84) and in the Symptoms/Stiffness and Sport/Recreation subscales of Knee Injury Osteoarthritis Outcome Score at 2 years (96.57 ± 5.97 vs 93.57 ± 6.52, P < .05) and (90.2 ± 17.76 vs 82.8 ± 16.08, P < .05). CONCLUSIONS: The use of biphasic scaffold loaded with autologous cartilage in treating focal osteochondral lesions demonstrates superior clinical outcomes and better cartilage refill on magnetic resonance imaging at the 2-year follow-up compared to marrow stimulation. LEVEL OF EVIDENCE: Level I, Randomized controlled trial.

Postoperative Rehabilitation after Anterior Cruciate Ligament Reconstruction through Telerehabilitation with Artificial Intelligence Brace during COVID-19 Pandemic.

BACKGROUND: Due to the rapid spread of the coronavirus disease-19 (COVID-19), most of the patients expressed a reluctance to undergo postoperative rehabilitation at a rehabilitation clinic. Therefore, in this scenario it was necessary to reshape the crucial role of postoperative rehabilitation of these patients. We conducted a telerehabilitation program based on an artificial intelligence brace (AI brace) which can monitor the progress of rehabilitation through an app and an internet server. Our hypothesis was that home-based telerehabilitation might provide clinical outcomes comparable to face-to-face, hospital-based rehabilitation programs in terms of effectiveness. METHODS: A retrospective cohort study enrolled patients who received anterior cruciate ligament reconstruction (ACLR) between January and September 2020. Patients were divided into two groups: the tele-AI group received telerehabilitation with an AI brace while the FTF group had face-to-face, hospital-based rehabilitation. Clinical knee functional scores and Tegner Activity Scale (TAS) were assessed and analyzed until 12 months after the operation. RESULTS: The tele-AI group had higher IKDC scores at 3 months (p = 0.0443) and 6 months (p = 0.0052) after surgery and higher KOOS scores at 1 month (p = 0.0365) and 6 months (p = 0.0375) after surgery. However, no significant difference between the two groups was detected at the end of the follow-up. The tele-AI group had higher TAS than FTF group after 1 year. CONCLUSIONS: Telerehabilitation after ACLR seems to provide a superior short-term outcome compared to hospital-based rehabilitation during the COVID-19 pandemic.

Introduction to the feature issue on augmented/virtual reality: optics & photonics.

In recent years, augmented/virtual reality (AR/VR) has been attracting attention and investment in both the tech and academic communities, kickstarting a new wave of innovations. In the wake of this momentum, this feature issue was launched to cover the latest advances in this burgeoning field that pertains to optics and photonics. Alongside the 31 research articles being published, this introduction is appended to share with readers the behind-the-issue stories, submission statistics, reading guides, author biographies, and editors' perspectives.

Implantable metaverse with retinal prostheses and bionic vision processing.

We present an implantable metaverse featuring retinal prostheses in association with bionic vision processing. Unlike conventional retinal prostheses, whose electrodes are spaced equidistantly, our solution is to rearrange the electrodes to match the distribution of ganglion cells. To naturally imitate the human vision, a scheme of bionic vision processing is developed. On top of a three-dimensional eye model, our bionic vision processing is able to visualize the monocular image, binocular image fusion, and parallax-induced depth map.

Design of single-layer color echelle grating optical waveguide for augmented-reality display.

We proposed a single-layer color echelle grating combined optical waveguide structure for an augmented-reality display. In this structure, we used echelle gratings with super-wavelength periodic scale as in-coupling, relay, and out-coupling elements. The combined propagation of three light beams in the waveguide was realized by overlapping different high diffraction orders of the RGB three primary colors, and deflection of the beam direction between gratings was achieved by conical diffraction generated by the inclined grating. Using the vector diffraction theory, the structural parameters and tolerance ranges of the three types of gratings were optimized, rendering average diffraction efficiencies of the three primary colors of the in-coupling, relay, and out-coupling gratings greater than 74%, 21%, and 35%, respectively. As a result, we obtained dual-channel one-dimensional pupil dilation of the original image and a field-of-view angle of h18.9° × v36.87°.

Near-eye display with a triple-channel waveguide for metaverse.

We present a near-eye display featuring a triple-channel waveguide with chiral liquid crystal gratings. Our triple-channel waveguide is capable of dividing one field of view into three through both the polarization orthogonality and angular separation. To illustrate its principle, a k-space diagram, which takes into account the aspect ratio of field of view, is depicted. Our results demonstrate that its diagonal field of view reaches 90°, eye relief is 10 mm, exit pupil is 4.9 × 4.9 mm2, transmittance is 4.9%, and uniformity is 89%.

Validation and modification of the Coronal Plane Alignment of the Knee classification in the Asian population.

AIMS: The Coronal Plane Alignment of the Knee (CPAK) classification is a simple and comprehensive system for predicting pre-arthritic knee alignment. However, when the CPAK classification is applied in the Asian population, which is characterized by more varus and wider distribution in lower limb alignment, modifications in the boundaries of arithmetic hip-knee-ankle angle (aHKA) and joint line obliquity (JLO) should be considered. The purposes of this study were as follows: first, to propose a modified CPAK classification based on the actual joint line obliquity (aJLO) and wider range of aHKA in the Asian population; second, to test this classification in a cohort of Asians with healthy knees; third, to propose individualized alignment targets for different CPAK types in kinematically aligned (KA) total knee arthroplasty (TKA). METHODS: The CPAK classification was modified by changing the neutral boundaries of aHKA to 0° ± 3° and using aJLO as a new variable. Radiological analysis of 214 healthy knees in 214 Asian individuals was used to assess the distribution and mean value of alignment angles of each phenotype among different classifications based on the coronal plane. Individualized alignment targets were set according to the mean lateral distal femoral angle (LDFA) and medial proximal tibial angle (MPTA) of different knee types. RESULTS: A very high concentration, 191 from 214 individuals (89.3%), were found in knee types with apex distal JLO when the CPAK classification was applied in the Asian population. By using aJLO as a new variable, the high distribution percentage in knee types with apex distal JLO decreased to 125 from 214 individuals (58.4%). The most common types in order were Type II (n = 70; 32.7%), Type V (n = 55; 25.7%), and Type I (n = 46; 21.5%) in the modified CPAK classification. CONCLUSION: The modified CPAK classification corrected the uneven distribution when applying the CPAK classification in the Asian population. Setting individualized TKA alignment targets according to CPAK type may be a practical method to recreate optimal LDFA and MPTA in KA-TKA. Cite this article: Bone Jt Open 2022;3(3):211-217.

Multimodal Biosensing for Vestibular Network-Based Cybersickness Detection.

Virtual reality (VR) has the potential to induce cybersickness (CS), which impedes CS-susceptible VR users from the benefit of emerging VR applications. To better detect CS, the current study investigated whether/how the newly proposed human vestibular network (HVN) is involved in flagship consumer VR-induced CS by simultaneously recording autonomic physiological signals as well as neural signals generated in sensorimotor and cognitive domains. The VR stimuli were made up of one or two moderate CS-inducing entertaining task(s) as well as a mild CS-inducing cognitive task implemented before and after the moderate CS task(s). Results not only showed that CS impaired cognitive control ability, represented by the degree of attentional engagement, but also revealed that combined indicators from all three HVN domains could together establish the best regression relationship with CS ratings. More importantly, we found that every HVN domain had its unique advantage with the dynamic changes in CS severity and time. These results provide evidence for involvement of the HVN in CS and indicate the necessity of HVN-based CS detection.

Biomechanical comparisons of different diagonal screw designs in a novel embedded calcaneal slide plate.

BACKGROUND: Medial displacement calcaneal osteotomy (MDCO) is frequently used for the surgical correction of flatfoot. This study aims to investigate the biomechanical effect of the different diagonal screw design on a novel-designed embedded calcaneal plate for MDCO using finite element analysis (FEA), mechanical test and digital image correlation (DIC) measurement. METHODS: Four groups according to the varied implanted plate were set as control group (Group 1), non-diagonal screw (Group 2), one-diagonal screw (Group 3), and two-diagonal screws groups (Group 4). For FEA, A 450 N load was applied to on the anterior process of the calcaneus from top to bottom. Observational indices included the stress on the cortical and cancellous bone of the calcaneus surrounding the implant, the plate itself as well as screws, and the displacement of the overall structure. In addition, this study also used in vitro biomechanics test to investigate the stiffness of the structure after implantation, and used DIC to observe the displacement of the calcaneus structure after external force. RESULTS: Under a simulated load in FEA, there are significant overall instability and high stress concentration on the calcaneal surrounding host bone and the plate/screws system, respectively, in group 2 compared with other groups. Regard to the mechanical testing with DIC system, significant increased rotation stability, maximum force and stiffness with the addition of diagonal screws. In comparison to Group 2, the increase of 112% and 157% in maximum force as well as 104% and 176% in stiffness were found in Group 3 and 4, respectively. CONCLUSION: For reducing stress concentration and enhancing overall stability, more than one-diagonal screw design is recommended and two-diagonal screws design will be superior. This study provided biomechanical references for further calcaneal implants design to prevent clinical failure after MDCO.

Improved Sensitivity of Surface-Enhanced Raman Scattering with Gold Nanoparticles-Insulator-Metal Sandwich Layers on Flat Sapphire Substrate.

Surface-enhanced Raman scattering (SERS) as a high sensitivity analytical method for molecule detection has attracted much attention in recent research. In this work, we demonstrated an improved SERS substrate, which has the gold nanoparticles randomly distributed on a SiO2 interception layer over a gold thin film layer on the flat sapphire substrate (AuNP/SiO2/Au/Sapphire), over the dispersed gold nanoparticles on a silicon substrate (AuNP/Si), for detection of R6G (1 × 10-6 M) in a Raman microscope. The fabrication of sandwich layers on top of the sapphire substrate involves evaporation of a gold mirror as thick as 100 nm, plasma enhanced chemical vapor deposition of the silica insulator layer 10 nm thick, and evaporation of a thin gold layer 10 nm thick for forming gold nanoparticles. For comparison, a gold thin film with a thickness of 5 nm and 10 nm was evaporated on a silicon substrate, respectively (AuNP/Si), as the reference SERS substrates in the experiment. The AuNP/SiO2/Au/Sapphire substrate demonstrated improved sensitivity in detection of molecules in Raman microscopy, which can enable the molecules to be recognizable at a low laser power as 8.5 × 10-3 mW, 0.017 mW, 0.085 mW, and 0.17 mW for ultrashort exposure time. The simulation of AuNP/SiO2/Au/Sapphire substrate and AuNP/Si substrate, based on the finite-difference time-domain (FDTD) method, explained the improved sensitivity for detection of R6G molecules from the view of classical electromagnetics, and it suggested the optimized size for the gold nanoparticles and the optimized laser wavelength for Raman microscopy for further research.

Effect of introducing biologics to patients with rheumatoid arthritis on the risk of venous thromboembolism: a nationwide cohort study.

In the United States, 100,000-300,000 patients die from venous thromboembolism (VTE) each year, with more than 500,000 people related hospitalizations. While in Europe, 500,000 people die from VTE each year. Patients with rheumatoid arthritis are at increased risk of VTE. The use of biologics in patients with rheumatoid arthritis may be associated with an increased risk of VTE. We identified all patients who had been newly approved for Catastrophic Illness Card of rheumatoid arthritis extracted the claims data from the National Health Insurance research database and Registry for Catastrophic Illness Patient Database from 2003 to 2016. VTE was defined as the presence of inpatient VTE diagnostic codes (including DVT or PE) according to the discharge diagnosis protocol. An analysis of VTE variables indicated that the incidence of VTE in the biologic group (14.33/10,000 person-years) was higher than that in the conventional drug group (12.61/10,000 person-years). As assessed by the Cox proportional hazards model, the relative HR for VTE in the biologic group (HR: 1.11; 95% CI 0.79-1.55) versus that in the conventional drug group did not reach a significant difference. In conclusion, this study found no significant differences in risk were observed between the use of conventional DMARDs and biologics.

Modified Superior Capsule Reconstruction Using the Long Head of the Biceps Tendon as Reinforcement to Rotator Cuff Repair Lowers Retear Rate in Large to Massive Reparable Rotator Cuff Tears.

PURPOSE: To retrospectively assess the clinical outcomes of the patients with large to massive reparable RCTs treated by arthroscopic rotator cuff repair (ARCR) combined with modified superior capsule reconstruction (mSCR) using the long head of biceps tendon (LHBT) as reinforcement with a minimum of 2 years of follow-up. METHODS: We retrospectively evaluated 40 patients with large to massive reparable RCTs who underwent ARCR and mSCR (group I) between February 2017 and June 2018 (18 patients) or underwent ARCR and tenotomy of LHBT performed at the insertion site (group II) between January 2015 and January 2017 (22 patients). The pain visual analog score (VAS) was assessed preoperatively and 1, 3, 6, 12, 24 months postoperatively. American Shoulder and Elbow Surgeons (ASES) scores, the University of California, Los Angeles (UCLA) shoulder rating scale, and active range of motion (AROM) were assessed before surgery and 6, 12, and 24 months after surgery. The integrity of the rotator cuff and mSCR was evaluated using magnetic resonance images at 12 months postoperatively. RESULTS: After surgery, both groups had significantly improved in VAS, ASES, UCLA and AROM scores in the final follow-up. There were no significant between-group differences in the characteristics of the patients before surgery. Group I had improved pain relief at 1 month (P < .001) and at 3 months (P < .01) after surgery. For the AROM, group I (flexion, external rotation, internal rotation) demonstrated better improvement than group II 6 months after surgery (all P < .05) and better internal rotation 12 and 24 months after surgery (all P < .05). The mSCR survival rate was 94.4% (17/18). The retear rate of repaired rotator cuffs for groups I and II was 16.7% (3/18) and 40.9% (9/22), respectively, and the differences were significant (P < .046). CONCLUSIONS: ARCR combined with mSCR using LHBT as reinforcement may lead to a lower retear rate and earlier functional recovery than conventional ARCR with tenotomy of LHBT for large to massive reparable RCTs. LEVEL OF EVIDENCE: Level III, retrospective therapeutic comparative trial.

The Prevention of Periprosthetic Joint Infection in Primary Total Hip Arthroplasty Using Pre-Operative Chlorhexidine Bathing.

Periprosthetic joint infection (PJI) after total hip arthroplasty (THA) is a devastating complication. The aim of this study was to investigate whether preoperative bathing using chlorhexidine gluconate (CHG) before THA can effectively reduce the postoperative PJI rate. A total of 933 primary THA patients, with the majority being female (54.4%) were included in the study. Primary THA patients who performed preoperative chlorhexidine bathing were assigned to the CHG group (190 subjects), and those who did not have preoperative chlorhexidine bathing were in the control group (743 subjects). The effects of chlorhexidine bathing on the prevention of PJI incidence rates were investigated. Differences in age, sex, and the operated side between the two groups were not statistically significant. Postoperative PJI occurred in four subjects, indicating an infection rate of 0.43% (4/933). All four infected subjects belonged to the control group. Although the PJI cases were significantly more in the control group than in the CHG group, statistical analysis revealed no statistical significance in the risk of PJI occurrence between the two groups (p = 0.588). Preoperative skin preparation by bathing with a 2% chlorhexidine gluconate cleanser did not produce significant effects on the prevention of postoperative PJI in primary THA.

Reflective Bistable Chiral Splay Nematic Liquid Crystal for Low-Power Heat Sensor.

The memory effect of the bistable liquid crystal mode is able to maintain the display information for a long time. The splay state and π twist states are used as the memory states of the bistable chiral splay nematic (BCSN) mode. The transition time from the π twist state to the splay state is sensitive to the temperature. In this paper, for the heat sensor application, the reflective structure of the BCSN mode has been studied by the Jones matrix method. In experiments, the measured contrast ratio can be over 200 with a minimal reflective structure including a single polarizer and a reflector.

Posterior cruciate ligament reconstruction implemented by the Ligament Advanced Reinforcement System over a minimum follow-up of 10 years.

PURPOSE: This study evaluated the long-term clinical follow-up results of patients who underwent double-bundle posterior cruciate ligament (PCL) reconstruction using the Ligament Advanced Reinforcement System (LARS). METHODS: Patients were assessed using clinical scores that included the Tegner activity level scale, the Lysholm score, and the International Knee Documentation Committee (IKDC) score. KT-1000 was adopted to assess stability. Radiographs and magnetic resonance imaging (MRI) were used to evaluate osteoarthritis and LARS condition. RESULTS: This study examined 38 patients, of which follow-up procedures were completed for 33 patients, resulting in a follow-up rate of 86.8%. The average follow-up period was 11.9 ±â€¯1.2 years (range: 10.3-14.2 years). The median scores of the clinical scales were as follows: Tegner activity score, 6 (range: five to seven); Lysholm score, 90 (range: 67-100); and IKDC score, 89.7 (range: 46-100). The median of the side-to-side difference (SSD) was four millimeters (range: 0-10 mm). In radiographs, the moderate OA rate was 6.9%. MRI results revealed that 26 patients exhibited ingrowth and 11 patients exhibited partial rupture of the LARS. With SSD ≤ 3 mm set as the standard for successful knee stabilization, the optimal cutoff point of LARS midsubstance thickness in the receiver operating characteristic (ROC) curve analysis was 14.3 mm. CONCLUSIONS: Long-term follow-up of the studied patients demonstrated the durability of LARS. However, clinical outcomes showed no enhancement using LARS, so it is not recommended for routine use in PCL reconstruction. LEVEL OF EVIDENCE: IV.

Design of foveated contact lens display for augmented reality.

We present a design of a contact lens display, which features an array of collimated light-emitting diodes and a contact lens, for the augmented reality. By building the infrastructure directly on top of the eye, eye is allowed to move or rotate freely without the need of exit pupil expansion nor eye tracking. The resolution of light-emitting diodes is foveated to match with the density of cones on the retina. In this manner, the total number of pixels as well as the latency of image processing can be significantly reduced. Based on the simulation, the device performance is quantitatively analyzed. For the real image, modulation transfer functions is 0.669757 at 30 cycle/degree, contrast ratio is 5, and distortion is 10%. For the virtual image, the field of view is 82°, best angular resolution is 0.38', modulation transfer function is above 0.999999 at 30 cycle/degree, contrast ratio is 4988, and distortion is 6%.

Design of lensless retinal scanning display with diffractive optical element.

We propose a design of a retinal-scanning-based near-eye display for augmented reality. Our solution is highlighted by a laser scanning projector, a diffractive optical element, and a moist eye with gradient refractive indices. The working principles related to each component are comprehensively studied. Its key performance is summarized as follows. The field of view is 122°, angular resolution is 8.09', diffraction efficiency is 57.6%, transmittance is 80.6%, uniformity is 0.91, luminance is 323 cd/m2, modulation transfer functions are above 0.99999 at 3.71 cycle/degree, contrast ratio is 4878, and distortion is less than 24%.

Effect of time interval from diagnosis to treatment for cervical cancer on survival: A nationwide cohort study.

OBJECTIVES: Despite the ease of health care access and the waiver of copayments for cancer patients, treatment is delayed in a small proportion of Taiwanese patients diagnosed with cervical cancer. In this study, we explored the relationship between the time interval from diagnosis to treatment and survival in cervical cancer patients. MATERIAL AND METHODS: The study was a retrospective population-based observational study conducted between 2004 and 2010. In Taiwan, 12,020 patients were newly diagnosed with cervical cancer from 2004 to 2010, and 9,693 patients (80.6%) were enrolled in our final analysis. RESULTS: Most of the patients received treatment within 90 days of diagnosis (n = 9,341, 96.37%). After adjustment for other variables, patients who received treatment between 90 and 180 days and >180 days after diagnosis had a 1.33 (95% CI: 1.02-1.72, P < 0.05) and 1.36 (95% CI: 1.12-1.65, P < 0.05) times higher risk of death, respectively, than those who received treatment within 90 days. Kaplan-Meier analysis showed that the patients treated after 90 days from diagnosis had a lower overall survival rate than those treated within 90 days. In analysis stratifying the patients according to their initial tumor stage, namely stages I and II and stage III and IV, the time interval from diagnosis to treatment remained a significant prognosticator in those who received treatment >180 days after diagnosis. CONCLUSION: A longer interval between diagnosis and treatment is associated with poorer prognosis among cervical cancer patients.

Ouabain induces apoptotic cell death in human prostate DU 145 cancer cells through DNA damage and TRAIL pathways.

Ouabain, a cardiotonic steroid and specific Na+ /K+ -ATPase inhibitor, has a potential to induce cancer cell apoptosis but the mechanisms of apoptosis induced by ouabain are not fully understand. The aim of this study was to investigate the cytotoxic effects of ouabain on human prostate cancer DU 145 cells in vitro. Cell morphological changes were examined by phase contrast microscopy. Cell viability, cell cycle distribution, cell apoptosis, DNA damage, the production of ROS and Ca2+ , and mitochondrial membrane potential (ΔΨm ) were measured by flow cytometry assay. Results indicated that ouabain induced cell morphological changes, decreased total cell viability, induced G0/G1 phase arrest, DNA damage, and cell apoptosis, increased ROS and Ca2+ production, but decreased the levels of ΔΨm in DU 145 cells. Ouabain also increased the activities of caspase-3, -8, and -9. Western blotting was used for measuring the alterations of apoptosis-associated protein expressions in DU 145 cells and results indicated that ouabain increased the expression of DNA damage associated proteins (pATMSer1981 , p-H2A.XSer139 , and p-p53Ser15 ) and ER-stress-associated proteins (Grp78, ATF6ß, p-PERKThr981 , PERK, eIF2A, GADD153, CaMKIIß, and caspase-4) in time-dependently. Furthermore, ouabain increased apoptosis-associated proteins (DR4, DR5, Fas, Fas Ligand, and FADD), TRAIL pathway, which related to extrinsic pathway, promoted the pro-apoptotic protein Bax, increased apoptotic-associated proteins, such as cytochrome c, AIF, Endo G, caspase-3, -8, and -9, but reduced anti-apoptotic protein Bcl-2 and Bcl-x in DU 145 cells. In conclusion, we may suggest that ouabain decreased cell viability and induced apoptotic cell death may via caspase-dependent and mitochondria-dependent pathways in human prostate cancer DU 145 cells.

Activity-related outcome in anterior cruciate ligament reconstruction with synthetic ligament advanced reinforcement system.

BACKGROUND: Arthroscopic anterior cruciate ligament (ACL) reconstruction with ligament advanced reinforcement system (LARS) had revealed good results with low complication and failure rate in series of studies. The specific candidates for ACL reconstruction with LARS are still unknown anyway. The purpose of this study is to evaluate the activity-related outcome in ACL reconstruction using LARS ligament. METHODS: A total of 43 unilateral arthroscopic ACL reconstructions with LARS were collected and divided into two groups: group A (preinjury Tegner score ≥ 6, n = 20) and group B (preinjury Tegner score < 6, n = 23). We had analyzed the stability of knee and functional outcome with a minimum of 2-years follow up. RESULTS: All patients were aware of improvement over the knee stability immediately after ACL reconstruction with LARS. The functional outcome of knee was improved in both groups by analysis with the Lysholm score and modified International Knee Documentation Committee (IKDC) score. The postoperative grading of the knee examination form of modified IKDC grade showed no statistical difference in both groups. CONCLUSION: Arthroscopic ACL reconstruction with LARS was encouraged as an alternative option even in high sports demand patients.