Computer-assisted simulated workplace-based assessment in surgery: application of the universal framework of intraoperative performance within a mixed-reality simulation.

Objectives: Workplace-based assessment (WBA) is a key requirement of competency-based medical education in postgraduate surgical education. Although simulated workplace-based assessment (SWBA) has been proposed to complement WBA, it is insufficiently adopted in surgical education. In particular, approaches to criterion-referenced and automated assessment of intraoperative surgical competency in contextualized SWBA settings are missing.

Pain levels during distraction osteogenesis with lengthening nails in 168 cases.

Purpose: To firstly examine the pain levels during distraction osteogenesis (DO) with lengthening nails (LN) in a large sample.

Methods: A total of 168 cases underwent DO of the tibia or femur with five different models of LN. Under a standardized medical regime, daily pain levels were noted as nominal rating scale (NRS) score (0-10) during the distraction phase.

Novel approach to estimate distraction forces in distraction osteogenesis and application in the human lower leg.

Purpose: In distraction osteogenesis (DO) of long bones, new bone tissue is distracted to lengthen limbs or reconstruct bone defects. However, mechanical boundary conditions in human application such as arising forces are mainly based on limited empirical data. Our aim was the numerical determination of the callus distraction force (CDF) and the total distraction force (TDF) during DO in the tibia of adults to advance the understanding of callus tissue behavior and optimize DO procedures.

[Prophylactic fasciotomy in tibial osteotomies: functional results].

Background: Intramedullary nailing in tibial osteotomy (TO) can be combined with minimally invasive prophylactic fasciotomy (PF) of the anterior compartment of the lower leg to prevent postoperative acute compartment syndrome (CS). So far no studies are available on the effects of TO or PF on specific functions of the extensor muscles.

Objective: To investigate the medium-term outcome after PF in TO in patients without preoperative functional impairment.

Complications and Effectiveness of Intramedullary Limb Lengthening: A Matched Pair Analysis of Two Different Lengthening Nails.

Background: Intramedullary limb lengthening has become an accepted concept in reconstructive surgery, but as yet comparative clinical studies are missing. We compared the complications and effectiveness of two types of intramedullary limb lengthening devices (ISKD®; Fitbone®).

Materials And Methods: In a retrospective series of 278 consecutive patients with internal limb lengthening, we found 17 matching pairs in terms of predefined matching parameters (group I with ISKD® and group II with Fitbone®).

Novel method for determining bone dimensions relevant for longitudinal and transverse distraction osteogenesis and application in the human tibia and fibula.

Background: In distraction osteogenesis (DO) of long bones, new bone tissue is formed and distracted to lengthen limbs or reconstruct bone defects. However, certain anthropometric quantities relevant for biomechanical modelling of DO are unknown, such as areas where new bone tissue is formed. We developed a novel method to facilitate the determination of these distraction areas (DA), which we applied in the tibia and fibula of adults for longitudinal and transverse DO to advance knowledge of anatomical boundary conditions.

Three-dimensional-Printed Computed Tomography-Based Bone Models for Spine Surgery Simulation.

Introduction: We present a novel 3-dimensional (3D) printing method for low-cost and widely available reproduction of computed tomography (CT)-based synthetic bone models for spine surgery simulation, optimized to reproduce realistic haptic properties. The method allows reproduction of either normal or abnormal patient anatomy. The models are fluoroscopy compatible and contain deformities and fractures present in the underlying CT data.

Three-dimensional assessment of lower limb alignment: Reference values and sex-related differences.

Background: Three-dimensional (3D) preoperative planning and assisted surgery is increasingly popular in deformity surgery and arthroplasty. Reference ranges for 3D lower limb alignment are needed as a prerequisite for standardized analysis of alignment and preoperative planning in 3D, but are not yet established.

Methods: On 60 3D bone models of the lower limbs based on computed tomography data, fifteen parameters per leg were assessed by standardized validated 3D analysis.

Intraoperative customization of intramedullary nails - First results.

Introduction: Intramedullary nailing is a valuable treatment option for many types of fractures. Furthermore nailing is applicable for osteosynthesis following osteotomy in deformity correction. For intraoperative fine-tuning of alignment in intramedullary (IM) nailing procedures, a bending device for customization of IM nails under sterile conditions was developed.

Video-augmented fluoroscopy for distal interlocking of intramedullary nails decreased radiation exposure and surgical time in a bovine cadaveric setting.

Background: We aimed to assess the feasibility of a video-augmented fluoroscopy (VAF) technique using a camera-augmented mobile C-arm (CamC) for distal interlocking of intramedullary nails.

Methods: Three surgeons performed distal interlocking on seven pairs of cadaveric bovine carpal bones using the VAF system and conventional fluoroscopy. We compared radiation exposure, procedure time, and drilling quality between the VAF system and conventional fluoroscopic guidance.

[Team training and assessment in mixed reality-based simulated operating room : Current state of research in the field of simulation in spine surgery exemplified by the ATMEOS project].

Surgical simulators are being increasingly used as an attractive alternative to clinical training in addition to conventional animal models and human specimens. Typically, surgical simulation technology is designed for the purpose of teaching technical surgical skills (so-called task trainers). Simulator training in surgery is therefore in general limited to the individual training of the surgeon and disregards the participation of the rest of the surgical team.

[3D augmented reality visualization for navigated osteosynthesis of pelvic fractures].

Background: Despite great advances in the development of hardware and software components, surgical navigation systems have only seen limited use in current clinical settings due to their reported complexity, difficulty of integration into clinical workflows and questionable advantages over traditional imaging modalities.

Objectives: Development of augmented reality (AR) visualization for surgical navigation without the need for infrared (IR) tracking markers and comparison of the navigation system to conventional imaging.

Material And Methods: Novel navigation system combining a cone beam computed tomography (CBCT) capable C‑arm with a red-green-blue depth (RGBD) camera.

Camera-augmented mobile C-arm (CamC): A feasibility study of augmented reality imaging in the operating room.

Background: In orthopaedic trauma surgery, image-guided procedures are mostly based on fluoroscopy. The reduction of radiation exposure is an important goal. The purpose of this work was to investigate the impact of a camera-augmented mobile C-arm (CamC) on radiation exposure and the surgical workflow during a first clinical trial.

Analysis of the three-dimensional anatomical variance of the distal radius using 3D shape models.

Background: Various medical fields rely on detailed anatomical knowledge of the distal radius. Current studies are limited to two-dimensional analysis and biased by varying measurement locations. The aims were to 1) generate 3D shape models of the distal radius and investigate variations in the 3D shape, 2) generate and assess morphometrics in standardized cut planes, and 3) test the model's classification accuracy.

An augmented reality C-arm for intraoperative assessment of the mechanical axis: a preclinical study.

Background: Determination of lower limb alignment is a prerequisite for successful orthopedic surgical treatment. Traditional methods include the electrocautery cord, alignment rod, or axis board which rely solely on C-arm fluoroscopy navigation and are radiation intensive.

Study Objectives: To assess a new augmented reality technology in determining lower limb alignment.

Preclinical usability study of multiple augmented reality concepts for K-wire placement.

Purpose: In many orthopedic surgeries, there is a demand for correctly placing medical instruments (e.g., K-wire or drill) to perform bone fracture repairs.

Using self-drilling screws in volar plate osteosynthesis for distal radius fractures: a feasibility study.

Background: Symptomatic extensor tendon irritation is a frequent complication in volar plate osteosynthesis of distal radius fractures. It is typically caused by dorsal screw protrusion and overdrilling of the dorsal cortex. The use of self-drilling locking screws (SDLS) could overcome both causes.

Personalized augmented reality for anatomy education.

Anatomy education is a challenging but vital element in forming future medical professionals. In this work, a personalized and interactive augmented reality system is developed to facilitate education. This system behaves as a "magic mirror" which allows personalized in-situ visualization of anatomy on the user's body.

Intra-operative disruptions, surgeon's mental workload, and technical performance in a full-scale simulated procedure.

Background And Aim: Surgical flow disruptions occur frequently and jeopardize perioperative care and surgical performance. So far, insights into subjective and cognitive implications of intra-operative disruptions for surgeons and inherent consequences for performance are inconsistent. This study aimed to investigate the effect of surgical flow disruption on surgeon's intra-operative workload and technical performance.

Intra-operative augmented reality in distal locking.

Purpose: To design an augmented reality solution that assists surgeons during the distal locking of intramedullary nailing procedures.

Method: Traditionally, the procedure is performed under X-ray guidance and requires a significant amount of time and radiation exposure. To absolve these complications, we propose video guidance that allows surgeons to achieve both the down-the-beam position of the intramedullary nail and its subsequent locking.

Multi-modal intra-operative navigation during distal locking of intramedullary nails.

The interlocking of intramedullary nails is a technically demanding procedure which involves a considerable amount of X-ray acquisitions; one study lists as many as 48 to successfully complete the procedure and fix screws into 4-6 mm distal holes of the nail. We propose to design an augmented radiolucent drill to assist surgeons in completing the distal locking procedure without any additional X-ray acquisitions. Using an augmented reality fluoroscope that coregisters optical and X-ray images, we exploit solely the optical images to detect the augmented radiolucent drill and estimate its tip position in real-time.

Necrotizing fasciitis in a young patient with acute myeloid leukemia - a diagnostic challenge.

Background: Necrotizing fasciitis is characterized by a fulminant destruction of the soft tissue with an alarmingly high mortality rate. One of the main reasons for the continued high mortality is due to the challenge to punctual recognize and diagnose this disease, as specific cutaneous signs can vary or even be missing early in its evolution - especially in case of simultaneous first manifestation of an acute leukemia.

Case Presentation: An untypical case of necrotizing fasciitis disease in a young patient with the first diagnosis of acute myeloid leukemia is presented.

Machine learning-based augmented reality for improved surgical scene understanding.

In orthopedic and trauma surgery, AR technology can support surgeons in the challenging task of understanding the spatial relationships between the anatomy, the implants and their tools. In this context, we propose a novel augmented visualization of the surgical scene that mixes intelligently the different sources of information provided by a mobile C-arm combined with a Kinect RGB-Depth sensor. Therefore, we introduce a learning-based paradigm that aims at (1) identifying the relevant objects or anatomy in both Kinect and X-ray data, and (2) creating an object-specific pixel-wise alpha map that permits relevance-based fusion of the video and the X-ray images within one single view.