Extrusion and meniscal mobility evaluation in case of ramp lesion injury: a biomechanical feasibility study by 7T magnetic resonance imaging and digital volume correlation

Introduction: The existing body of literature on the biomechanical implications of ramp lesions is limited, leaving a significant gap in our understanding of how these lesions impact joint kinematics and loading in the medial compartment. This cadaveric biomechanical study aims to address this gap by employing an innovative Digital Volume Correlation (DVC) method, utilizing 7 Tesla Magnetic Resonance Imaging (MRI) images under various loading conditions. The primary objective is to conduct a comprehensive comparison of medial meniscal mobility between native knees and knees affected by grade 4 ramp lesions. By focusing on the intricate dynamics of meniscal mobility and extrusion, this work seeks to contribute valuable insights into the biomechanical consequences of medial meniscus ramp lesions. Materials and methods: An initial set of 7T MRI imaging sessions was conducted on two intact native knees, applying load values up to 1500N. Subsequently, a second series of images was captured on these identical knees, with the same loads applied, following the creation through arthroscopy of medial meniscus ramp lesions. The application of DVC enabled the precise determination of the three components of displacement and spatial variations in the medial menisci, both with and without ramp lesions. Results: The measured directional displacements between native knees and injured knees indicate that, following the application of axial compression load, menisci exhibit increased extrusion and posterior mobility as observed through DVC. Discussion: Injuries associated with Subtype 4 medial meniscus ramp lesions appear to elevate meniscal extrusion and posterior mobility during axial compression in the anterior cruciate ligament of intact knees. Following these preliminary results, we plan to expand our experimental approach to encompass individuals undergoing weight-bearing MRI. This expansion aims to identify meniscocapsular and/or meniscotibial insufficiency or rupture in patients, enabling us to proactively reduce the risk of osteoarthritic progression.

[Flap harvest training on a new ultrarealistic simulation model: In-training operator feedback about a pulsating reperfused and reventilated cadaver Simlife®]

INTRODUCTION

The anatomical subject is still a key element to learn complex procedures in plastic surgery. We present here the evaluation of an in-training operator on a SIMLIFE® model, hyper realistic model consisting in human bodies donated to science equipped with pulsating recirculation and reventilation device.

MATERIAL AND METHODS

From February 2019 to October 2019, 8 forearm flaps with radial proximal pedicle were harvested by the learner on a SIMLIFE® model. Conditions were as close as possible to the operating room : asepsy, sterile draping, assistant and instrumentation including electrocoagulation.

RESULTS

The procedure was decomposed in 13 distinct steps. Mean total surgery time was 90,5±11,62minutes. There was only one case of arterial pedicle lesion resulting in major blood leak. Bleeding was measured by fake blood loss from the SIMLIFE® console. Mean intraoperatoy bleeding was 171±108 milliliters. We review pros and cons of this new technology particulary suited for complex plastic and reconstructive surgery training.

CONCLUSION

Using SIMLIFE® technology we have a new mean to train for complex procedures in plastic and reconstructive surgery. This new technology could be applied to numerous other surgical procedures. Broader applications are still limited by cost and cadaver use legislation.

SimLife model: introducing a new teaching device in endocrine surgery simulation

To evaluate the validity and reliability of an innovative training model for endocrine surgical procedures. A simulator training model for endocrine procedures (SimLife) was developed at an academic center. The model consisted of a realistic operating environment with a coherent simulated patient dynamized by pulsatile vascularization with simulated blood warmed to 37 °C, and ventilation. Training sessions were designed for adrenal and thyroid surgery, as well as neck dissection. The primary outcome of interest was to evaluate learners’ performance and satisfaction. Learners’ performance was evaluated based on a scoring scale that followed the Downing method for the assessment of competency. While learners’ satisfaction was evaluated using a Likert scale of 1 to 10 on four items (ease of learning, anatomic correspondence of landmarks, realism, and overall satisfaction). Participants were engaged in 32 training sessions. These included 24 adrenalectomies (conventional and laparoscopic both transabdominal and posterior), and 4 thyroid lobectomies with concomitant functional lateral compartment neck dissection. competency scores were procedure-specific addressing specific core components of a given procedure. Learners’ performance scored above average in all procedures evaluated. Satisfaction scores for the specified four items ranged between 8.43 (SD 0.87) and 8.89 (SD 0.96). No major events were reported for the adrenalectomies, while only one jugular vein injury occurred during neck dissection. SimLife is a hyper-realistic training model that allows for satisfactory acquisition of skills and the evaluation of performance progression. It has the potential to become a cornerstone in specialized surgical training.

Bariatric Surgical Simulation: Evaluation in a Pilot Study of SimLife, a New Dynamic Simulated Body Model

Background

The demand for bariatric surgery is high and so is the need for training future bariatric surgeons. Bariatric surgery, as a technically demanding surgery, imposes a learning curve that may initially induce higher morbidity. In order to limit the clinical impact of this learning curve, a simulation preclinical training can be offered. The aim of the work was to assess the realism of a new cadaveric model for simulated bariatric surgery (sleeve and Roux in Y gastric bypass).

Aim

A face validation study of SimLife, a new dynamic cadaveric model of simulated body for acquiring operative skills by simulation. The objectives of this study are first of all to measure the realism of this model, the satisfaction of learners, and finally the ability of this model to facilitate a learning process.

Methods

SimLife technology is based on a fresh body (frozen/thawed) given to science associated to a patented technical module, which can provide pulsatile vascularization with simulated blood heated to 37 °C and ventilation.

Results

Twenty-four residents and chief residents from 3 French University Digestive Surgery Departments were enrolled in this study. Based on their evaluation, the overall satisfaction of the cadaveric model was rated as 8.52, realism as 8.91, anatomic correspondence as 8.64, and the model’s ability to be learning tool as 8.78.

Conclusion

The use of the SimLife model allows proposing a very realistic surgical simulation model to realistically train and objectively evaluate the performance of young surgeons.

Sleeve Gastrectomy: You Might Lose your Liver!

Sleeve gastrectomy (SG) is currently the most popular bariatric procedure. Portomesenteric venous thrombosis (PVT) is a feared and increasingly reported complication. Herein, we describe the history of a patient who developed a post-operative PVT after SG, aggravated with refractory ascites, and finally required orthotopic liver transplantation (LT). Acquired thrombophilia-anti-cardiolipin syndrome was present. As SG expands worldwide, this first case of LT for PVT following SG may warrant a systematic screening for prothrombotic condition and information on the possible consequences of PVT prior to bariatric surgery.

The EVACO Project: A new battery for assessing social cognition disorders and related psychiatric disability in schizophrenia

The relation of social cognitive disorders and schizophrenic symptoms are well-established. Yet, assessment methods have not reached a consensus. In addition, causal paths between neurocognition, social cognition, symptoms and functional expression are not clearly understood. During the past few years, some authoritative accounts proposed specialized batteries of tests and emphasized theory of mind, emotion recognition, and interpretation bias constructs:

– NIMH's “Social cognition psychometric evaluation” battery (Pinkham AE, Penn DL, Green MF, Harvey PD. Schizophrenia Bulletin, 2015);

– “Social cognition and functioning in schizophrenia” (Green MF, Lee J, Ochsner KN. Schizophrenia Bulletin, 2013).

Interestingly, these accounts stemming either from expert consensus and psychometric considerations or from neuroscience knowledge recognized some difficulties in providing a fully usable set of instruments. The project described here (EVACO protocol, funded by the Programme Hospitalier de Recherche Clinique national) follows an alternative approach and aims at providing a psychometrically validated battery. Based on a cognitive neuropsychology view on schizophrenic functional disability, several tests were gathered and are assessed in a 12-months multi-center follow-up of 160 individuals with schizophrenia. The FondaMental foundation network of Expert Centers is involved in recruiting patients from eight centers (Clermont-Ferrand, Colombes, Créteil, Grenoble, Marseille, Montpellier, Strasbourg, Versailles). To-date, the first evaluation of the population has been achieved. Experience reports and inclusions follow-up demonstrate the good acceptability of this battery both on the patients and the evaluator's side. We emphasize the usefulness of this project to meet the clinicians’ needs of validated social cognition tools, by describing different scenarios of use.

Disclosure of interest

The authors have not supplied their declaration of competing interest.