This paper introduces a novel respiratory detection system based on diaphragm wall motion tracking using an embedded ultrasound sensory system. We assess the utility and accuracy of this method in evaluating the function of the diaphragm and its contribution to respiratory workload. The developed system is able to monitor the diaphragm wall activity when the sensor is placed in the zone of apposition (ZOA). This system allows for direct measurements with only one ultrasound PZT5 piezo transducer. The system generates pulsed ultrasound waves at 2.2 MHz and amplifies reflected echoes. An added benefit of this system is that due to its design, the respiratory signal is less subject to motion artefacts. Promising results were obtained from six subjects performing six tests per subject with an average respiration detection sensitivity and specificity of 84% and 93%, respectively. Measurements were compared to a gold standard commercial spirometer. In this study, we also compared our measurements to other conventional methods such as inertial and photoplethysmography (PPG) sensors.

Augmented reality (AR) is a natural extension of computer-assisted surgery whereby a computer-generated image is superimposed on the surgeon's field of vision to assist in the planning and execution of the procedure. This emerging technology shows great potential in the field of arthroplasty, improving efficiency, limb alignment, and implant position. AR has shown the capacity to build on computer navigation systems while providing more elaborate information in a streamlined workflow to the user. This review investigates the current uses of AR in the field of arthroplasty and discusses outcomes, limitations, and potential future directions.

Purpose: To examine the ability of surgeons to identify the osseous landmarks associated with the femoral anterior cruciate ligament (ACL) footprint and locate optimal tunnel placement on 3‐dimensional (3D) printed models compared with intraoperative placement. Methods: Twelve sports fellowship‐trained orthopaedic surgeons were asked to identify a femoral landmark and an ACL footprint on 10 different 3D printed knees. The 3D models were made based on 20 real patients with different anatomical morphology who later received ACL reconstructive surgery using independent drilling. ImageJ software was used to quantify the measurements, which were then analyzed using descriptive statistics. Results: Overall, none of the surgeons were able to consistently identify the junction of the bony ridges. The mean error per participant ranged from 2.81 to 7.34 mm in the proximal direction ( P = 3.30e‐05) and from 2.42 to 8.05 mm in the posterior direction ( P =4.88e‐12). None of the surgeons were able to appropriately identify the center of the femoral footprint on the anatomic 3D models. The difference between the center of the footprint surgeons identified on the 3D model and the tunnel graft location in surgery was significantly different ( P = .0046). On average, the magnitude of the error when the surgeons performed the actual surgery was 3.72 ± 2.43 mm, whereas on the 3D models it was 5.82 ± 1.97 mm. Conclusions: Experienced sports fellowship‐trained orthopaedic surgeons were unable to correctly identify the junction of the intercondylar and bifurcate ridges and the native ACL footprint on 3D models. Operatively placed tunnels were more accurate implying that looking either through a scope or soft‐tissue landmarks play a significant role in surgeons ACL footprint localization. Clinical Relevance: The graft position for ACL reconstruction plays an important role on the kinematics of the knee. This paper shows that soft tissue landmarks are needed to provide reliable reference points for reconstruction.

Background: The sliding hip screw (SHS) is frequently used in the management of hip fractures; successful placement depends on accurate positioning of the lag screw in the femoral head guided by fluoroscopy. We proposed to leverage the capabilities of augmented reality (AR) to overlay virtual images of the desired guidewire trajectory directly onto the surgical field to guide the surgeon during SHS guidewire insertion. Methods: Using a commercially available AR headset and software, we performed preprocedural planning using computed tomography scans to identify the optimal trajectory for SHS guidewire insertion in the neck of a Sawbones femur model. The images of the scanned femurs containing the virtual guidewire trajectory were overlaid on the physical models such that the user could see a composite view of the computer-generated images and the physical environment. Two second-year orthopedic residents each inserted 15 guidewires under AR guidance and 15 guidewires under fluoroscopy. Results: Of the 30 guidewires inserted under AR guidance, 24 (80%) were within the femoral neck, and 16 (53%) were fully enclosed within the femoral head. Nine (56%) of the 16 perforations were due to insertions that were too far along the planned trajectory. Thirteen (81%) of the successful attempts with AR had an appropriate position, compared to 25/26 (96%) with fluoroscopy. It took significantly less time to perform the procedure using fluoroscopy than AR (p < 0.05). Fluoroscopy required on average 18.7 shots. Conclusion: Augmented reality provides an opportunity to aid in guidewire insertion in a preplanned trajectory with less radiation exposure in a sterile environment, but technical challenges remain to be solved to enable widespread adoption. Contexte: La vis de hanche à compression coulissante (VHCC) est souvent utilisée pour la prise en charge des fractures de la hanche; son bon positionnement dépend de l’installation précise de la vis tire-fond dans la tête fémorale sous fluoroscopie. Nous avons proposé d’utiliser les capacités de la réalité augmentée (RA) pour surimposer des images virtuelles de la trajectoire du fil-guide désirée directement sur le site opératoire dans le but de faciliter la tâche du chirurgien pendant l’insertion du filguide de la VHCC. Méthodes: À l’aide d’un logiciel et d’un casque de RA du commerce, nous avons préplanifié l’intervention à l’aide de clichés de tomodensitométrie (TDM) pour l’insertion optimale du fil-guide de VHCC dans le col fémoral d’un modèle de fémur Sawbones. Des clichés de TDM de fémurs montrant la trajectoire du fil guide virtuel ont été surimposés aux modèles physiques pour que l’utilisateur puisse avoir une image composite des vues générées par ordinateur et de l’environnement physique. Deux résidents de deuxième année en orthopédie ont chacun inséré 15 fils-guides à l’aide de la RA et 15 fils-guides sous fluoroscopie. Résultats: Des 30 fils-guides insérés à l’aide de la RA, 24 (80 %) se trouvaient dans le col fémoral et 16 (53 %) étaient entièrement à l’intérieur de la tête fémorale. Neuf (56 %) des 16 perforations étaient dues à des insertions trop profondes le long de la trajectoire planifiée. Treize (81 %) des tentatives réussies avec la RA étaient bien positionnées, contre 25/26 (96 %) avec la fluoroscopie. L’intervention sous fluoroscopie a nécessité significativement moins de temps que l’intervention sous RA (p < 0,05). La fluoroscopie a demandé en moyenne 18,7 clichés. Conclusion: La RA offre la possibilité de faciliter l’insertion du fil-guide quand la trajectoire est préplanifiée, tout en réduisant l’exposition aux radiations dans un environnement stérile, mais il reste des difficultés techniques à régler avant de pouvoir en généraliser l’adoption.

Case: A 32-year-old patient was diagnosed with a vertical patella fracture nonunion after a bone–patellar tendon–bone (BTB) anterior cruciate ligament reconstruction. In addition, a 1 × 2 × 1 cm patellar bone defect was noticed at the graft harvesting site. The patient was treated surgically with open reduction and internal fixation and iliac crest bone autograft which resulted in fracture union. Conclusion: Many intraoperative and postoperative risk factors for iatrogenic patella fracture when harvesting BTB autograft were identified. Surgeons should be aware of technical skills needed to prevent this complication and should treat the fracture appropriately to avoid nonunion and optimize the outcome.