Validation of an Augmented Reality Based Functional Method to Determine and Render the Hip Rotation Centre During Total Hip Arthroplasty.

Background: We present a method to determine and visualise the functional centre of rotation (FCOR) of the hip during total hip arthroplasty using an augmented reality head mounted display (AR-HMD).

Methods: We developed software allowing a HoloLens to provide inside-out infrared tracking of markers affixed to cadaver femurs and 3D printed acetabuli. Two observers rotated 20 cadaver femurs twice in a matching cup, producing 80 measurements.

Augmented reality guidance improves accuracy of orthopedic drilling procedures.

In several orthopedic procedures, the accurate use of surgical power tools is critical to avoid damage to surrounding tissues. As such, various guidance techniques and safety measures were developed. Augmented reality (AR) guidance shows promise but requires validation.

Investigating patellar motion using weight-bearing dynamic CT: normative values and morphological considerations for healthy volunteers.

Background: Patellar instability is a well-known pathology in which kinematics can be investigated using metrics such as tibial tuberosity tracheal groove (TTTG), the bisect offset (BO), and the lateral patellar tilt (LPT). We used dynamic computed tomography (CT) to investigate the patellar motion of healthy subjects in weight-bearing conditions to provide normative values for TTTG, BO, and LPT, as well as to define whether BO and LPT are affected by the morphology of the trochlear groove.

Methods: Dynamic scanning was used to acquire images during weight-bearing in 21 adult healthy volunteers.

Linking Intra-Articular Inflammatory Biomarkers with Peripheral and Central Sensitization in Late-Stage Knee Osteoarthritis Pain: A Pilot Study.

: To investigate if intra-articular biomarkers relate to peripheral and central sensitization in patients with late-stage knee osteoarthritis (KOA). : A total of 17 (6M, 11F) patients (aged 69 ± 10 years) were assessed for peripheral (pressure pain thresholds (PPT)) and central (temporal summation (TS) and conditioned pain modulation (CPM)) sensitization the day before total knee arthroplasty. Synovial fluid was collected during surgery and assayed for IL-6, IL-8, IL-10, TNF-α, CXCL-10, BDNF, NGF, CCL2, CCL5, VEGF, IL-1RI, MMP-1, MMP-7, IL-1β, and CXCL-9.

Discussing sexual health with patients eligible for spine surgery: An online survey in spine surgeon and pain physicians.

Introduction: Spinal pain syndromes have a severe impact on the patient's sex life, contributing to a decrease in sexual function and sexual satisfaction. Despite the importance of sexual health on mental and physical wellbeing, sexual health is rarely discussed during consultations.

Research Question: The aim of this study is to explore to what extent influencing factors can alter the discussion about sexual health during consultations.

Automated analysis of trapeziometacarpal joint kinematics using four-dimensional computed tomography.

The aim of this study was to develop an automated approach model to define in vivo kinematics of the trapeziometacarpal (TMC) joint using four-dimensional computed tomography. A total of 15 healthy volunteers were included and their TMC joint kinematics were studied during a retropulsion-opposition-retropulsion movement. We used cardan angles estimated from transformation matrices using a ZYX-decomposition and analysed the motion of the thumb metacarpal relative to the trapezium, the thumb metacarpal relative to the index metacarpal, and the trapezium relative to the index metacarpal.

Introducing a pharmacist-led transmural care program to reduce drug-related problems in orthogeriatric patients: a prospective interventional study.

Background: Orthogeriatric patients have an increased risk for complications due to underlying comorbidities, chronic drug therapy and frequent treatment changes during hospitalization. The clinical pharmacist (CP) plays a key role in transmural communication concerning polypharmacy to improve continuity of care by the general practitioner (GP) after discharge. In this study, a pharmacist-led transmural care program, tailored to orthogeriatric patients, was evaluated to reduce drug related problems (DRPs) after discharge.

Exploring technology acceptance of head-mounted device-based augmented reality surgical navigation in orthopaedic surgery.

Background: This study used the Unified Theory of Acceptance and Use of Technology (UTAUT) to investigate the acceptance of HMD-based AR surgical navigation.

Methods: An experiment was conducted in which participants drilled 12 predefined holes using freehand drilling, proprioceptive control, and AR assistance. Technology acceptance was assessed through a survey and non-participant observations.

Dynamic CT scanning of the knee: Combining weight bearing with real-time motion acquisition.

Background: Imaging the lower limb during weight-bearing conditions is essential to acquire advanced functional joint information. The horizontal bed position of CT systems however hinders this process. The purpose of this study was to validate and test a device to simulate realistic knee weight-bearing motion in a horizontal position during dynamic CT acquisition and process the acquired images.

Neuro-oncological augmented reality planning for intracranial tumor resection.

Background: Before starting surgery for the resection of an intracranial tumor, its outlines are typically marked on the skin of the patient. This allows for the planning of the optimal skin incision, craniotomy, and angle of approach. Conventionally, the surgeon determines tumor borders using neuronavigation with a tracked pointer.

Financial implications of the renewed reimbursement system of total hip arthroplasty in Belgium.

In Belgium, from June 1st 2018 on, a renewed reim- bursement for hip arthroplasty implants was launched and from January 1st 2019 on, a lump sum covering doctors' fees for "low variable patients", was introduced. We investigated the impact of both reimbursement systems on the funding of a University Hospital in Belgium. All patients from the UZ Brussel with a severity of illness score of one or two whom had an elective total hip replacement implanted between January 1st and May 31st 2018, were included retrospectively.

The use of cardiac CT acquisition mode for dynamic musculoskeletal imaging.

Objectives: To quantitatively evaluate the impact of a cardiac acquisition CT mode on motion artifacts in comparison to a conventional cine mode for dynamic musculoskeletal (MSK) imaging.

Methods: A rotating PMMA phantom with air-filled holes drilled at varying distances from the disk center corresponding to linear hole speeds of 0.75 cm/s, 2.

Defining trapezial dysplasia - analysis of trapezial inclination in a normal population.

We assess the distribution of trapezial inclination in a young population in order to propose a threshold for trapezial dysplasia. One hundred peritrapezial views were reconstructed from wrist computed tomography scan datasets to measure trapezial inclination. Seventy peritrapezial views were constructed from 10 datasets to assess the influence of radiograph rotation.

The effect of augmented reality on the accuracy and learning curve of external ventricular drain placement.

Objective: The traditional freehand technique for external ventricular drain (EVD) placement is most frequently used, but remains the primary risk factor for inaccurate drain placement. As this procedure could benefit from image guidance, the authors set forth to demonstrate the impact of augmented-reality (AR) assistance on the accuracy and learning curve of EVD placement compared with the freehand technique.

Methods: Sixteen medical students performed a total of 128 EVD placements on a custom-made phantom head, both before and after receiving a standardized training session.

Hip implants can restore anatomical and medialized rotation centres in most cases : a 3D templating study comparing four implantation strategies.

Aims: Hip arthroplasty does not always restore normal anatomy. This is due to inaccurate surgery or lack of stem sizes. We evaluated the aptitude of four total hip arthroplasty systems to restore an anatomical and medialized hip rotation centre.

Analysis of the effects of a delay of surgery in patients with hip fractures: outcome and causes.

Unlabelled: This study analyzed characteristics of hip fracture patients who did not undergo surgery within 24 hours after hospitalization, as recommended by the Belgian quality standards. Reasons for delay were analyzed. Delay in surgery for hip fracture was related to the medical condition of the patients.

Evaluating lower limb kinematics and pathology with dynamic CT.

Evaluating musculoskeletal conditions of the lower limb and understanding the pathophysiology of complex bone kinematics is challenging. Static images do not take into account the dynamic component of relative bone motion and muscle activation. Fluoroscopy and dynamic MRI have important limitations.

Introduction of the orthogeriatric co-management model increases the quality of care : a pilot study.

Traditionally, geriatric patients with musculoskeletal or osteoarticular problems will be admitted to an orthopedic ward and will be treated by sur- geons. However, these patients often suffer from comorbidities requiring geriatric management. In this study, the orthogeriatric co-management (OG- CM) model is compared to traditional orthopedic care model in a retrospective pilot study.

Augmented Reality-Assisted Neurosurgical Drain Placement (ARANED): Technical Note.

Background: Many surgical procedures, such as placement of intracranial drains, are currently being performed blindly, relying on anatomical landmarks. As a result, accuracy results still have room for improvement. Neuronavigation could address this issue, but its application in an urgent setting is often impractical.

Radiological measurement of trapezial dysplasia - variation of trapezial tilt and trapezial inclination.

Trapeziometacarpal instability is a well-known condition that could lead to trapeziometacarpal osteoarthritis. With the focus in the literature being on ligament insufficiency, bony deformity has received much less attention. Although trapezial tilt is currently used to measure trapezial dysplasia, we believe trapezial inclination is a more reliable measurement.

Cemented short-stem total hip arthroplasty: Characteristics of line-to-line versus undersized cementing techniques using a validated CT-based finite element analysis.

Short stems are becoming increasingly popular in total hip arthroplasty as they preserve the bone stock and simplify the implantation process. Short stems are advised mainly for patients with good bone stock. The clinical use of short stems could be enlarged to patients with poor bone stock if a cemented alternative would be available.

Clinical and Radiographic Outcome of Gap Balancing Versus Measured Resection Techniques in Total Knee Arthroplasty.

Background: There is no consensus regarding superiority between gap balancing (GB) and measured resection (MR) techniques to implant total knee arthroplasties. In a multicenter setup, we compared both techniques using the same prosthesis.

Methods: We included 262 balanSys posterior-stabilized total knee arthroplasties from 4 centers: 3 using the MR (n = 162) and one using the GB technique (n = 100), without navigation.

Effect of anatomical variability on stress-shielding induced by short calcar-guided stems: Automated finite element analysis of 90 femora.

Short stem hip implants are becoming increasingly popular since they preserve bone stock and presumably reduce stress-shielding. However, concerns remain whether they are suitable for a wide range of patients with varying anatomy. The aim of this study was to investigate how femoral anatomy influences stress-shielding induced by a short calcar-guided stem across a set of 90 CT-based femur models.