Virtual Reality Single-Port Sleeve Gastrectomy Training Decreases Physical and Mental Workload in Novice Surgeons: An Exploratory Study.

BACKGROUND: Novice surgeons experience high levels of physical and mental workload during the early stages of their curriculum and clinical practice. Laparoscopic sleeve gastrectomy is the first bariatric procedure worldwide. Feasibility and safety of single-port sleeve gastrectomy (SPSG) has been demonstrated. An immersive virtual reality (VR) simulation was developed to provide a repetitive exercise to learn this novel technique. The primary objective of this study was to evaluate the impact of the VR training tool on mental and physical workload in novice surgeons. The secondary objective included an evaluation of the VR simulator. METHODS: A monocentric-controlled trial was conducted. Ten participants were divided into two groups, the VR group and the control group (without VR training). Surgery residents participated in a first real case of SPSG and a second case 1 month later. The VR group underwent a VR training between the two surgeries. Mental and physical loads were assessed with self-assessment questionnaires: NASA-TLX, Borg scale, and manikin discomfort test. The VR simulator was evaluated through presence, cybersickness, and usability questionnaires. RESULTS: This study showed a decrease of the mental demand and effort dimensions of NASA-TLX between the first and the second surgery in the VR group (P < .05). During the second surgery, a marginally significant difference was shown concerning the mental demand between the two groups. Postural discomfort of the VR group decreased with practice (P < .01), mainly between the first and the second surgery (P < .05). Furthermore, participants characterized the VR simulator as realistic, usable, and very useful to learned surgery. CONCLUSION: This exploratory study showed an improvement in mental and physical workload when novice surgeons trained with VR (repetitive practice, gesture improvement, reduction of stress, etc.). Virtual reality appears to be a promising perspective for surgical training.

Fat content of hip muscles: an anteroposterior gradient.

BACKGROUND: Despite the importance of the hip muscles in protecting against hip fracture and in the outcome of hip arthroplasty, the variability in their fat content has not been previously studied. Our objectives were to evaluate the variability in the fat content of the hip muscles in a population without myopathy or a need for hip surgery with the use of computed tomography (CT), to study the relationship between hip muscle fat content and physical performance, and to identify medical conditions and lifestyle habits associated with an increase in hip muscle fat content. METHODS: Ten normal subjects without a relevant medical history and ninety-nine consecutive nonsurgical patients without myopathy (age, twenty-one to ninety-four years) underwent a nonenhanced CT scan of the pelvis. Patients were asked to perform physical tests (six-meter walk, repeated chair stands, and Trendelenburg test), and their level of physical activity and medical history were recorded. Evaluation of the fat content of the hip muscles was based on the analysis of four reproducible and representative CT slices with use of custom software. RESULTS: The fat content varied among the muscles, with an anteroposterior gradient from the hip flexors (mean, 2%) to the hip extensors (mean, 10%). This gradient increased after fifty years of age. Fat content also varied considerably among patients. Higher fat content was associated with poorer performance on physical tests, even after adjustment for the cross-sectional area of the muscle (p < 0.05). Higher fat content was also associated with greater age, higher body-mass index, and lower physical activity (p < 0.001). CONCLUSIONS: The observed variability in the fat content of individuals without myopathy or a need for hip surgery should be useful for comparison with future studies of specific populations of patients, such as those with muscle weakness secondary to hip fracture or hip surgery. Simple lifestyle changes such as dietary restriction, increased physical activity, and vitamin D supplementation may decrease muscle fat content and improve physical performance in the elderly.

Three-dimensional stereoradiographic modeling of rib cage before and after spinal growing rod procedures in early-onset scoliosis.

BACKGROUND: Early-onset scoliosis frequently leads to major thoracic deformity and pulmonary restrictive disease. Growing rods surgical techniques were developed to achieve a satisfactory correction of the spinal curves during growth. The effect on the rib cage deformity has not yet been documented. The purpose of this study was to analyze the changes of the thoracic geometry after implantation of a growing rod, and to evaluate a stereoradiographic reconstruction method among young scoliotic patients. METHODS: Four patients were enrolled in the study, and four additional patients in the reproducibility study. Three-dimensional spine and rib cage models were generated after low-dose stereoradiographic imaging (EOS). Three-dimensional parameters were computed before and after surgery. Intra and inter-observer reproducibility was calculated, and the accuracy was assessed in comparison to volumetric CT-scan. FINDINGS: The average Cobb angle was reduced from 50.8 degrees to 26 degrees . The surgery resulted in a complex 3D effect on the rib cage, combining frontal, lateral, and axial rotation. This effect was dependent of the side (concave or convex), and the position relative to the apical vertebra. Mean errors in comparison to CT-scan were 3.5mm. INTERPRETATION: The results on the spinal deformity are comparable to other series. The effect on the rib cage is of a smaller magnitude than in the case of a spinal arthrodesis. A longer follow-up is necessary to confirm the positive effect on the rib cage deformity. Further research should be performed to improve the reproducibility of 3D parameters.

Erector spinae muscle changes on magnetic resonance imaging following lumbar surgery through a posterior approach.

STUDY DESIGN: Prospective randomized study of patients undergoing lumbar arthrodesis. OBJECTIVES: To quantify MRI changes of the erector spinae following lumbar surgery through a posterior approach and the possible protection of these muscles during surgery by the use of cholinergic blockade. SUMMARY OF BACKGROUND DATA: It has been shown that lumbar spine surgery through a posterior approach can induce iatrogenic lesions in the erector spinae. We have shown in a previous study that histologic changes on muscular biopsy performed in the multifidus at the end of the surgical procedure were not modified by the use of cholinergic blockade during surgery. METHODS: Twenty patients scheduled to undergo pedicle-screw enhanced L4-L5 arthrodesis were enrolled in this study. Ten patients received curare during anesthesia and 10 patients did not. MRI was obtained the day before the operation and at 6 months of follow-up on the same MR scanner. T1-weighted images were obtained in the axial plane. The 2 slices immediately proximal and distal to the pedicle screw construct on the postoperative MRI were selected. The corresponding slices were selected on the preoperative MRI. Each erector spinae on the 4 slices was surrounded using a mouse-guided tool. The contractile component of the cross-sectional area (CCSA) was calculated from the number of pixels surrounded and the signal intensity of each pixel. RESULTS: There was only slight changes in the erector spinae CCSA proximal to a posterior lumbar arthrodesis. Erector spinae CCSA decreased by 27% distal to the arthrodesis. Curare showed no efficacy in preventing muscle damage. CONCLUSIONS: Erector spinae muscle alterations mainly occur distal to posterior lumbar surgical procedures.