Objective analysis of surgeons' ergonomy during laparoendoscopic single-site surgery through the use of surface electromyography and a motion capture data glove

Correlation Study and Predictive Modelling of Ergonomic Parameters in Robotic-Assisted Laparoscopic Surgery

BACKGROUND

This study aims to continue research on the objective analysis of ergonomic conditions in robotic-assisted surgery (RAS), seeking innovative solutions for the analysis and prevention of ergonomic problems in surgical practice.

METHODS

Four different robotic-assisted tasks were performed by groups of surgeons with different surgical experiences. Different wearable technologies were used to record surgeons' posture and muscle activity during surgical practice, for which the correlation between them was analyzed. A predictive model was generated for each task based on the surgeons' level of experience and type of surgery. Two preprocessing techniques (scaling and normalization) and two artificial intelligence techniques were tested.

RESULTS

Overall, a positive correlation between prolonged maintenance of an ergonomically inadequate posture during RAS and increased accumulated muscle activation was found. Novice surgeons showed improved posture when performing RAS compared to expert surgeons. The predictive model obtained high accuracy for cutting, peg transfer, and labyrinth tasks.

CONCLUSIONS

This study expands on the existing ergonomic analysis of the lead surgeon during RAS and develops predictive models for future prevention of ergonomic risk situations. Both posture and muscle loading are highly related to the surgeon's previous experience.

Evolution of minimally invasive cholecystectomy: a narrative review

BACKGROUND

Laparoscopic cholecystectomy, being a prevalent abdominal surgical procedure, has transitioned through various innovative stages aimed at reducing the procedure's invasiveness. These stages encompass Single-Incision Laparoscopic Cholecystectomy (SILC), Mini Laparoscopic Cholecystectomy (MLC), Natural Orifice Transluminal Endoscopic Surgery (NOTES), and Robotic-Assisted Laparoscopic Cholecystectomy (RALC). The purpose of this review is to trace the evolution of minimally invasive cholecystectomy techniques, assess their status, and identify emerging trends and challenges in the field.

METHOD

An extensive review was performed to explore the evolution and characteristics of SILC, MLC, NOTES, and RALC. The approach involved an in-depth examination of literature available on PubMed, coupled with a critical assessment of surgical outcomes, associated complications, and technical hurdles posed by these methods.

RESULTS

SILC, despite its potential for reduced scarring, exhibits an elevated risk of bile duct damage and incisional hernia occurrences. MLC, mirroring the standard technique closely, presents minor benefits without amplifying postoperative complications, hence, positing itself as a feasible choice for routine elective cholecystectomy. NOTES, although still facing technical challenges, the hybrid transvaginal procedure is gaining clinical interest. RALC, heralded for its augmented precision and dexterity, emerges as a potential future avenue, although necessitating further exploration to ascertain its efficacy and safety.

CONCLUSION

The progression of laparoscopic cholecystectomy methodologies embodies the surgical society's aspiration to minimize invasiveness whilst enhancing patient outcomes. This review endeavors to offer a structured discourse on SILC, MLC, NOTES, and RALC, aspiring to aid the ongoing deliberation on the judicious selection of surgical techniques in clinical practice.

Comparative Study of Ergonomics in Conventional and Robotic-Assisted Laparoscopic Surgery

BACKGROUND

This study aims to implement a set of wearable technologies to record and analyze the surgeon's physiological and ergonomic parameters during the performance of conventional and robotic-assisted laparoscopic surgery, comparing the ergonomics and stress levels of surgeons during surgical procedures.

METHODS

This study was organized in two different settings: simulator tasks and experimental model surgical procedures. The participating surgeons performed the tasks and surgical procedures in both laparoscopic and robotic-assisted surgery in a randomized fashion. Different wearable technologies were used to record the surgeons' posture, muscle activity, electrodermal activity and electrocardiography signal during the surgical practice.

RESULTS

The simulator study involved six surgeons: three experienced (>100 laparoscopic procedures performed; 36.33 ± 13.65 years old) and three novices (<100 laparoscopic procedures; 29.33 ± 8.39 years old). Three surgeons of different surgical specialties with experience in laparoscopic surgery (>100 laparoscopic procedures performed; 37.00 ± 5.29 years old), but without experience in surgical robotics, participated in the experimental model study. The participating surgeons showed an increased level of stress during the robotic-assisted surgical procedures. Overall, improved surgeon posture was obtained during robotic-assisted surgery, with a reduction in localized muscle fatigue.

CONCLUSIONS

A set of wearable technologies was implemented to measure and analyze surgeon physiological and ergonomic parameters. Robotic-assisted procedures showed better ergonomic outcomes for the surgeon compared to conventional laparoscopic surgery. Ergonomic analysis allows us to optimize surgeon performance and improve surgical training.

Learning Skill Characteristics From Manipulations

Percutaneous coronary intervention (PCI) has increasingly become the main treatment for coronary artery disease. The procedure requires high experienced skills and dexterous manipulations. However, there are few techniques to model PCI skill so far. In this study, a learning framework with local and ensemble learning is proposed to learn skill characteristics of different skill-level subjects from their PCI manipulations. Ten interventional cardiologists (four experts and six novices) were recruited to deliver a medical guidewire to two target arteries on a porcine model for in vivo studies. Simultaneously, translation and twist manipulations of thumb, forefinger, and wrist are acquired with electromagnetic (EM) and fiber-optic bend (FOB) sensors, respectively. These behavior data are then processed with wavelet packet decomposition (WPD) under 1-10 levels for feature extraction. The feature vectors are further fed into three candidate individual classifiers in the local learning layer. Furthermore, the local learning results from different manipulation behaviors are fused in the ensemble learning layer with three rule-based ensemble learning algorithms. In subject-dependent skill characteristics learning, the ensemble learning can achieve 100% accuracy, significantly outperforming the best local result (90%). Furthermore, ensemble learning can also maintain 73% accuracy in subject-independent schemes. These promising results demonstrate the great potential of the proposed method to facilitate skill learning in surgical robotics and skill assessment in clinical practice.

Baseline performance in a robotic virtual reality platform predicts rate of skill acquisition in a proficiency-based curriculum: a cohort study of surgical trainees

BACKGROUND

Residency programs must prepare to train the next generation of surgeons on the robotic platform. The purpose of this study was to determine if baseline skills of residents on a virtual reality (VR) robotic simulator before intern year predicted future performance in a proficiency-based curriculum.

METHODS

Across two academic years, 21 general surgery PGY-1s underwent the robotic surgery boot camp at the University of Texas Southwestern. During boot camp, subjects completed five previously validated VR tasks, and their performance metrics (score, time, and economy of motion [EOM]) were extracted retrospectively from their Intuitive learning accounts. The same metrics were assessed during their residency until they reached previously validated proficiency benchmarks. Outcomes were defined as the score at proficiency, attempts to reach proficiency, and time to proficiency. Spearman's rho and Mann-Whitney U tests were used; median (IQR) was reported. Significance level was set at p < 0.05.

RESULTS

Twenty-one residents completed at least three out of the five boot camp tasks and achieved proficiency in the former during residency. The median average score at boot camp was 12.3 (IQR: 5.14-18.5). The median average EOM at boot camp was 599.58 cm (IQR: 529.64-676.60). The average score at boot camp significantly correlated with lower time to achieve proficiency (p < 0.05). EOM at boot camp showed a significant correlation with attempts to proficiency and time to proficiency (p < 0.01). Residents with an average baseline EOM below the median showed a significant difference in attempts to proficiency (p < 0.05) and time to proficiency (p < 0.05) compared to those with EOMs above or equal to the median.

CONCLUSION

Residents with an innate ability to perform tasks with better EOM may acquire robotic surgery skills faster. Future investigators could explore how these innate differences impact performance throughout residency.

Technical, ergonomic and cognitive learning methodology in transumbilical single-port laparoscopic hysterectomy

OBJECTIVE

We introduced learning curves on a detailed step protocol and ergonomic aspect to determine key surgical points in transumbilical single-port laparoscopic hysterectomy (TSPLH) and to popularize both technical and cognitive methodology on laparoendoscopic single-site surgery (LESS).

MATERIALS AND METHODS

A retrospective analysis of 87 TSPLH procedures was conducted by a single surgeon in three learning stages. Technical, ergonomic, and cognitive steps were introduced, and surgical outcomes were analyzed.

RESULTS

Key production points in TSPLH include developing a clear retroperitoneal space, maintaining appropriate strength and direction with a vaginal manipulator, coagulating the uterine artery, and applying an improved vaginal stump suturing method. Technical factors included instrument domination, hand-eye coordination, and alternating hand functions. Ergonomic techniques focused on shoulder, elbow, arm, wrist, and finger movements, range of motion, muscle power, continuous forces, and flexibility. Improved cognitive factors such as confidence, decision-making, and communication were also observed.

CONCLUSIONS

The study aimed to form methodological education on TSPLH and LESS and benefit more surgeons. The detailed production and key ergonomic points will help guide self-learning and education.

Learning-Based Multimodal Information Fusion and Behavior Recognition of Vascular Interventionists' Operating Skills

The operating skills of vascular interventionists have an important impact on the effect of surgery. However, current research on behavior recognition and skills learning of interventionists' operating skills is limited. In this study, an innovative deep learning-based multimodal information fusion architecture is proposed for recognizing and analyzing eight common operating behaviors of interventionists. An experimental platform integrating four modal sensors is used to collect multimodal data from interventionists. The ANOVA and Manner-Whitney tests is used for relevance analysis of the data. The analysis results demonstrate that there is almost no significant difference ( p <0.001) between the actions related to the unimodal data, which cannot be used for accurate behavior recognition. Therefore, a study of the fusion architecture based on the existing machine learning classifier and the proposed deep learning fusion architecture is carried out. The research findings indicate that the proposed deep learning-based fusion architecture achieves an impressive overall accuracy of 98.5%, surpassing both the machine learning classifier (93.51%) and the unimodal data (90.05%). The deep learning-based multimodal information fusion architecture proves the feasibility of behavior recognition and skills learning of interventionist's operating skills. Furthermore, the application of deep learning-based multimodal fusion technology of surgeon's operating skills will help to improve the autonomy and intelligence of surgical robotic systems.

Ergonomic Design and Assessment of an Improved Handle for a Laparoscopic Dissector Based on 3D Anthropometry

Laparoscopic surgery (LS) has been shown to provide great benefits to patients compared with open surgery. However, surgeons experience discomfort, low-efficiency, and even musculoskeletal disorders (MSDs) because of the poor ergonomic design of laparoscopic instruments. A methodology for the ergonomic design of laparoscopic dissector handles considering three-dimensional (3D) hand anthropometry and dynamic hand positions was addressed in this research. Two types of hand positions for grasping and stretching were scanned from 21 volunteers using a high-resolution 3D scanner. The 3D anthropometric data were extracted from these 3D hand pose models and used to design an improved handle (IH) that provides additional support for the thumb, a better fit to the purlicue, and a more flexible grasp for the index finger. Thirty subjects were invited to evaluate the IH in terms of muscular effort, goniometric study of motion, and efficiency and effectiveness during four trials of a laparoscopic training task. Questionnaires provided subjective parameters for ergonomic assessment. Positive results included less muscle load in the trapezius as well as significant but small angular differences in the upper limb. No significant reduction in the trial time and no increased percentage of the achievement were observed between the IH and the commercial handle (CH). Improved intuitiveness, comfort, precision, stability, and overall satisfaction were reported. IH provides significant ergonomic advantages in laparoscopic training tasks, demonstrating that the proposed methodology based on 3D anthropometry is a powerful tool for the handle design of laparoscopic dissectors and other surgical instruments.

A Multilayer and Multimodal-Fusion Architecture for Simultaneous Recognition of Endovascular Manipulations and Assessment of Technical Skills

The clinical success of the percutaneous coronary intervention (PCI) is highly dependent on endovascular manipulation skills and dexterous manipulation strategies of interventionalists. However, the analysis of endovascular manipulations and related discussion for technical skill assessment are limited. In this study, a multilayer and multimodal-fusion architecture is proposed to recognize six typical endovascular manipulations. The synchronously acquired multimodal motion signals from ten subjects are used as the inputs of the architecture independently. Six classification-based and two rule-based fusion algorithms are evaluated for performance comparisons. The recognition metrics under the determined architecture are further used to assess technical skills. The experimental results indicate that the proposed architecture can achieve the overall accuracy of 96.41%, much higher than that of a single-layer recognition architecture (92.85%). In addition, the multimodal fusion brings significant performance improvement in comparison with single-modal schemes. Furthermore, the K -means-based skill assessment can obtain an accuracy of 95% to cluster the attempts made by different skill-level groups. These hopeful results indicate the great possibility of the architecture to facilitate clinical skill assessment and skill learning.

Ergonomic assessment of a new hand tool design for laparoscopic surgery based on surgeons' muscular activity

Laparoscopic surgery techniques are customarily used in non-invasive procedures. That said traditional surgical instruments and devices used by surgeons suffer from certain ergonomic deficiencies that may lead to physical complaints in upper limbs and back and general discomfort that may, in turn, affect the surgeon's skills during surgery. A novel design of the laparoscopic gripper handle is presented and compared with one of the most used instruments in this field in an attempt to overcome this problem. The assessment of the ergonomic feature of the novel design was performed by using time-frequency analysis of the surface electromyography (sEMG) signal during dynamic activities. Singular Spectrum Analysis (SSA) was used to decompose the sEMG signal and extract the median frequency of each muscle to assess muscle fatigue. The results reveal that using the proposed ergonomic grip reduces the mean values of the muscle activity during each of the proposed tasks. The novel design also improves the ease of use in laparoscopic surgery as it minimises high-pressure contact areas, reduces large amplitude movements and promotes a neutral position of the hand, wrist and forearm. Furthermore, the SSA method for time-frequency analysis provides a powerful tool to analyse a prescribed activity in ergonomic terms. The proposed methodology to assess muscle activity during surgery activities may be useful in the selection of surgical instruments when programming extended procedures, as it provides an additional selection criterion based on the surgeon's biomechanics and the proposed activity.

An Objective Ergonomic Risk Assessment of Surgeons in Real Time While Performing Endoscopic Sinus Surgery

There are increased reports of high prevalence of work related musculoskeletal symptoms in surgeons performing otolaryngology procedures. However, real time ergonomic risk assessment in the OR is difficult due to issues related to sterility, cooperation and acceptance from surgeons. Although such analyses can provide valid risk estimate and guide corrective actions, they are scarce. Hence, this study was undertaken to assess the postural ergonomic risk on RULA in otolaryngologists while performing Functional Endoscopic Sinus Surgery in OR, in real time. A cross sectional, observational multi-centric study was conducted in tertiary referral hospitals. Spinal, shoulder and elbow movements of 10 surgeons performing FESS were measured intraoperatively using orientation sensor-based, motion-analysis system (Noraxon myomotion). Postural ergonomic risk on RULA was computed using the motion analysis data. RULA is a method of quantifying the physical postural risk of the trunk and upper limb based on the postures adopted by an individual during work. 10 surgeons (9 males and 1 female) with the mean (± SD) age of 38 ± 7.5 years participated in the study. The motion analysis data results indicate that the surgeons often adopt awkward spinal and upper extremity postures during the surgery. All the surgeons scored higher than the acceptable RULA score (1 or 2) with the mean RULA scores being in the range of 6-7. The physical ergonomic risk in surgeons performing FESS is high (> 6 on RULA). There is a need for urgent ergonomic attention to the working environment of FESS surgeon.

Comparative Study of the Use of Different Sizes of an Ergonomic Instrument Handle for Laparoscopic Surgery

Previous studies have shown that the handle design of laparoscopic instruments is crucial to surgical performance and surgeon’s ergonomics. In this study, four different sizes of an ergonomic laparoscopic handle design were tested in a blind and randomized fashion with twelve surgeons. They performed three laparoscopic tasks in order to analyze the influence of handle size. Execution time, wrist posture, and finger and palm pressure were evaluated during the performance of each task. The results show a significant reduction in the time required to complete the eye-manual coordination task using the appropriate handle. The incorrectly sized handle resulted in a rise in palm pressure and a reduction in the force exerted by the thumb during the transfer task. In the hand-eye coordination task, the use of the right handle size led to an increase in middle finger pressure. In general, surgeons had an ergonomically adequate wrist flexion in all tasks and an acceptable radio-ulnar deviation during the transfer task using the ergonomic instrument handle. Surgeons found it comfortable the use of the ergonomic handle. Therefore, the use of an appropriately sized instrument handle allows surgeons to improve ergonomics and surgical performance during the laparoscopic practice.

Multimodal Physiological Signals for Workload Prediction in Robot-assisted Surgery

Monitoring surgeon workload during robot-assisted surgery can guide allocation of task demands, adapt system interfaces, and assess the robotic system's usability. Current practices for measuring cognitive load primarily rely on questionnaires that are subjective and disrupt surgical workflow. To address this limitation, a computational framework is demonstrated to predict user workload during telerobotic surgery. This framework leverages wireless sensors to monitor surgeons’ cognitive load and predict their cognitive states. Continuous data across multiple physiological modalities (e.g., heart rate variability, electrodermal, and electroencephalogram activity) were simultaneously recorded for twelve surgeons performing surgical skills tasks on the validated da Vinci Skills Simulator. These surgical tasks varied in difficulty levels, e.g., requiring varying visual processing demand and degree of fine motor control. Collected multimodal physiological signals were fused using independent component analysis, and the predicted results were compared to the ground-truth workload level. Results compared performance of different classifiers, sensor fusion schemes, and physiological modality (i.e., prediction with single vs. multiple modalities). It was found that our multisensor approach outperformed individual signals and can correctly predict cognitive workload levels 83.2% of the time during basic and complex surgical skills tasks.

Qualitative and Quantitative Assessment of Technical Skills in Percutaneous Coronary Intervention: In Vivo Porcine Studies

OBJECTIVE

Technical skill assessment plays an important role in the professional development of an interventionalist in percutaneous coronary intervention (PCI). However, most of the traditional assessment methods are time consuming and subjective. This paper aims to develop objective assessment techniques.

METHODS

In this study, a natural-behavior-based assessment framework is proposed to qualitatively and quantitatively assess technical skills in PCI. In vivo porcine studies were conducted to deliver a medical guidewire to two target coronaries of left circumflex arteries by six novice and four expert interventionalists. Simultaneously, four types of natural behaviors (i.e., hand motion, proximal force, muscle activity, and finger motion) were acquired from the subjects' dominant hand and arm. The features extracted from the behaviors of different skill-level groups were compared using the Mann-Whitney U-test for effective behavior selection. The effective ones were further applied in the Gaussian-mixture-model-based qualitative assessment and Mahalanobis-distance-based quantitative assessment.

RESULTS

The qualitative assessment achieves an accuracy of 92% to distinguish the novice and expert attempts, which is significantly higher than that of using single guidewire motions. Furthermore, the quantitative assessment can assign objective and effective scores for all attempts, indicating high correlation ( R = 0.9225) to those obtained by traditional methods.

CONCLUSION

The objective, effective, and comprehensive assessment of technical skills can be provided by qualitatively and quantitatively analyzing interventionalists' natural behaviors in PCI.

SIGNIFICANCE

This paper suggests a novel approach for the technical skill assessment and the promising results demonstrate the great importance and effectiveness of the proposed method for promoting the development of objective assessment techniques.

European association for endoscopic surgery (EAES) consensus statement on single-incision endoscopic surgery

BACKGROUND

Laparoscopic surgery changed the management of numerous surgical conditions. It was associated with many advantages over open surgery, such as decreased postoperative pain, faster recovery, shorter hospital stay and excellent cosmesis. Since two decades single-incision endoscopic surgery (SIES) was introduced to the surgical community. SIES could possibly result in even better postoperative outcomes than multi-port laparoscopic surgery, especially concerning cosmetic outcomes and pain. However, the single-incision surgical procedure is associated with quite some challenges.

METHODS

An expert panel of surgeons has been selected and invited to participate in the preparation of the material for a consensus meeting on the topic SIES, which was held during the EAES congress in Frankfurt, June 16, 2017. The material presented during the consensus meeting was based on evidence identified through a systematic search of literature according to a pre-specified protocol. Three main topics with respect to SIES have been identified by the panel: (1) General, (2) Organ specific, (3) New development. Within each of these topics, subcategories have been defined. Evidence was graded according to the Oxford 2011 Levels of Evidence. Recommendations were made according to the GRADE criteria.

RESULTS

In general, there is a lack of high level evidence and a lack of long-term follow-up in the field of single-incision endoscopic surgery. In selected patients, the single-incision approach seems to be safe and effective in terms of perioperative morbidity. Satisfaction with cosmesis has been established to be the main advantage of the single-incision approach. Less pain after single-incision approach compared to conventional laparoscopy seems to be considered an advantage, although it has not been consistently demonstrated across studies.

CONCLUSIONS

Considering the increased direct costs (devices, instruments and operating time) of the SIES procedure and the prolonged learning curve, wider acceptance of the procedure should be supported only after demonstration of clear benefits.

Analysis of Interventionalists' Natural Behaviors for Recognizing Motion Patterns of Endovascular Tools During Percutaneous Coronary Interventions

Many robotic platforms can indeed reduce radiation exposure to clinicians during percutaneous coronary intervention (PCI), however, interventionalists' natural manipulations are rarely involved in robot-assisted PCI. This requires more attention to analyze interventionalists' natural behaviors during conventional PCI. In this study, four types of natural behavior (i.e., muscle activity, hand motion, proximal force, and finger motion) were synchronously acquired from ten subjects while performing six typical types of guidewire manipulation. These behaviors are evaluated by a hidden Markov model (HMM) based analysis framework for relevant behavior selection. Relevant behaviors are further used as the input of two HMM-based classification frameworks to recognize guidewire motion patterns. Experimental results show that under the basic classification framework (BCF), 91.01% and 93.32% recognition accuracies can be achieved by using all behaviors and relevant behaviors, respectively. Furthermore, the hierarchical classification framework can significantly enhance the recognition ability of relevant behaviors with an accuracy of 96.39%. These promising results demonstrate great potential of proposed methods for promoting the future design of human-robot interfaces in robot-assisted PCI.

A method for quantifying key components of the opening process for opening pouch-style packages containing medical devices

Healthcare-associated infections are a serious worldwide health concern. Although contaminated medical devices are an avenue for infection, little research has evaluated the techniques used to open sterile packages. The goal of this study was to develop a method to quantify aspects of the package opening process in accordance with opening guidelines and then to demonstrate this methodology through a small sample of clinicians opening two sizes of pouch-style packages. Using motion capture techniques, a method was designed to quantify 11 parameters associated with the opening process. The method was then tested with nine healthcare professionals. Results indicated that all participants crossed the sterile field when opening packages. When opening large packages, participants spent significantly more time over the simulated sterile field and there was a trend towards more manipulations as compared to opening smaller packages. This methodology can be used to quantify the opening process, compare opening practices, and for assessment during the learning process.

Application of a Perception Neuron® System in Simulation-Based Surgical Training

While multiple studies show that simulation methods help in educating surgical trainees, few studies have focused on developing systems that help trainees to adopt the most effective body motions. This is the first study to use a Perception Neuron^® system to evaluate the relationship between body motions and simulation scores. Ten medical students participated in this study. All completed two standard tasks with da Vinci Skills Simulator (dVSS) and five standard tasks with thyroidectomy training model. This was repeated. Thyroidectomy training was conducted while participants wore a perception neuron. Motion capture (MC) score that indicated how long the tasks took to complete and each participant’s economy-of-motion that was used was calculated. Correlations between the three scores were assessed by Pearson’s correlation analyses. The 20 trials were categorized as low, moderate, and high overall-proficiency by summing the training model, dVSS, and MC scores. The difference between the low and high overall-proficiency trials in terms of economy-of-motion of the left or right hand was assessed by two-tailed t-test. Relative to cycle 1, the training model, dVSS, and MC scores all increased significantly in cycle 2. Three scores correlated significantly with each other. Six, eight, and six trials were classified as low, moderate, and high overall-proficiency, respectively. Low- and high-scoring trials differed significantly in terms of right (dominant) hand economy-of-motion (675.2 mm and 369.4 mm, respectively) (p = 0.043). Perception Neuron^® system can be applied to simulation-based training of surgical trainees. The motion analysis score is related to the traditional scoring system.

Wearable Monitoring Devices for Biomechanical Risk Assessment at Work: Current Status and Future Challenges-A Systematic Review

Background: In order to reduce the risk of work-related musculoskeletal disorders (WMSDs) several methods have been developed, accepted by the international literature and used in the workplace. The purpose of this systematic review was to describe recent implementations of wearable sensors for quantitative instrumental-based biomechanical risk assessments in prevention of WMSDs. Methods: Articles written until 7 May 2018 were selected from PubMed, Scopus, Google Scholar and Web of Science using specific keywords. Results: Instrumental approaches based on inertial measurement units and sEMG sensors have been used for direct evaluations to classify lifting tasks into low and high risk categories. Wearable sensors have also been used for direct instrumental evaluations in handling of low loads at high frequency activities by using the local myoelectric manifestation of muscle fatigue estimation. In the field of the rating of standard methods, on-body wireless sensors network-based approaches for real-time ergonomic assessment in industrial manufacturing have been proposed. Conclusions: Few studies foresee the use of wearable technologies for biomechanical risk assessment although the requirement to obtain increasingly quantitative evaluations, the recent miniaturization process and the need to follow a constantly evolving manual handling scenario is prompting their use.

Assessment of Postural Ergonomics and Surgical Performance in Laparoendoscopic Single-Site Surgery Using a Handheld Robotic Device

Purpose. New laparoscopic devices are being continuously developed to overcome some of the technical and ergonomic limitations of laparoendoscopic single-site (LESS) surgery. This study aims to assess the surgeon’s surgical performance and ergonomics during the use of a handheld, robotic-driven, articulating laparoscopic instrument during LESS surgery. Methods. Seven right-handed experienced surgeons took part in this study. A set of basic suturing tasks and digestive and urological procedures in a porcine model were performed. Surgeons used both a conventional laparoscopic needle holder and a robotic device. The learning curve, execution time, and precision using the surgical needle were assessed. The surgeon’s posture was analyzed using a motion tracking system and a data glove. Results. After the training period, execution time on the intracorporeal suturing was significantly shorter using the conventional needle holder. The precision was higher using the conventional instrument in the horizontal plane, but the number of attempts to position the needle was lower using the robotic device (1.625 ± 0.250 vs 1.188 ± 0.375 attempts). The extension of the elbow (134.681 ± 14.35° vs 120.631 ± 13.134°) and the flexion of the shoulder (26.122 ± 7.411° vs 18.475 ± 14.166°) were significantly lower using the robotic instrument. The wrist posture using the robotic device was ergonomically acceptable during both surgical procedures. Conclusions. Results show a positive learning curve in ergonomics and surgical performance using the robotic instrument during LESS surgery. This instrument improves the surgeon’s body posture and the needle positioning errors. The use of the robotic instrument is feasible and safe during LESS partial nephrectomy and sigmoidectomy procedures.

Evaluating Swine Injection Technologies as a Workplace Musculoskeletal Injury Intervention: A Study Protocol

Intensification of modern swine production has led to many new technologies, including needleless injectors. Although needleless injectors may increase productivity (by reducing injection time) and reduce needlestick injuries, the effect on risk for musculoskeletal disorders is not clear. This project will compare conventional needles with needleless injectors in terms of cost, productivity, injury rates, biomechanical exposures, and worker preference. Muscle activity (EMG) and hand/wrist posture will be measured on swine workers performing injection tasks with both injection methods. Video recordings during the exposure assessments will compare the duration and productivity for each injection method using time-and-motion methods. Injury claim data from up to 60 pig barns will be analyzed for needlestick and musculoskeletal injuries before/after needleless injector adoption. Workers and managers will be asked about what they like and dislike about each method and what helps and hinders successful implementation. The information above will be input into a cost-benefit model to determine the incremental effects of needleless injectors in terms of occupational health, worker preference, and the financial “bottom line” of the farm. Findings will be relevant to the swine industry and are intended to be transferable to other new technologies in animal production.

Analysis of comfort and ergonomics for clinical work environments

Work related musculoskeletal disorders (WMSD) are a serious risk to workers' health in any work environment, and especially in clinical work places. These disorders are typically the result of prolonged exposure to non-ergonomic postures and the resulting discomfort in the workplace. Thus a continuous assessment of comfort and ergonomics is necessary. There are different techniques available to make such assessments, such as self-reports on perceived discomfort and observational scoring models based on the posture's relevant joint angles. These methods are popular in medical and industrial environments alike. However, there are uncertainties with regards to objectivity of these methods and whether they provide a full picture. This paper reports on a study about these methods and how they correlate with the activity of muscles involved in the task at hand. A wearable 4-channel electromyography (EMG) and joint angle estimation device with wireless transmission was made specifically for this study to allow continuous, long-term and real-time measurements and recording of activities. N=10 participants took part in an experiment involving a buzz-wire test at 3 different levels, with their muscle activity (EMG), joint angle scores (Rapid Upper Limb Assessment - RULA), self-reports of perceived discomfort (Borg scale) and performance score on the buzz-wire being recorded and compared. Results show that the Borg scale is not responsive to smaller changes in discomfort whereas RULA and EMG can be used to detect more detailed changes in discomfort, effort and ergonomics.

Initial experience using a robotic-driven laparoscopic needle holder with ergonomic handle: assessment of surgeons' task performance and ergonomics

PURPOSE

The objective of this study is to assess the surgeons' performance and ergonomics during the use of a robotic-driven needle holder in laparoscopic suturing tasks.

METHODS

Six right-handed laparoscopic surgeons with different levels of experience took part in this study. Participants performed a set of three different intracorporeal suturing tasks organized in ten trials during a period of five weeks. Surgeons used both conventional (Conv) and robotic (Rob) laparoscopic needle holders. Precision using the surgical needle, quality of the intracorporeal suturing performance, execution time and leakage pressure for the urethrovesical anastomosis, as well as the ergonomics of the surgeon's hand posture, were analyzed during the first, fifth and last trials.

RESULTS

No statistically significant differences in precision and quality of suturing performance were obtained between both groups of instruments. Surgeons required more time using the robotic instrument than using the conventional needle holder to perform the urethrovesical anastomosis, but execution time was significantly reduced after training ([Formula: see text] 0.05). There were no differences in leakage pressure for the anastomoses carried out by both instruments. After training, novice surgeons significantly improved the ergonomics of the wrist ([Formula: see text] 0.05) and index finger (Conv: 36.381[Formula: see text], Rob: 30.389[Formula: see text]; p = 0.024) when using the robotic instrument compared to the conventional needle holder.

CONCLUSIONS

Results have shown that, although both instruments offer similar technical performance, the robotic-driven instrument results in better ergonomics for the surgeon's hand posture compared to the use of a conventional laparoscopic needle holder in intracorporeal suturing.

Muscular workload of veterinary students during simulated open and laparoscopic surgery: A pilot study

OBJECTIVE

To compare upper extremity muscle activity and workload between simulated open surgery, multiple port laparoscopic surgery (MLS), and single incision laparoscopic surgery (SLS) techniques in veterinary students.

STUDY DESIGN

Pilot study.

POPULATION

Veterinary students (n = 10) from years 1 to 4.

METHODS

Bipolar skin surface electrodes were fixed bilaterally to the forearm flexor, forearm extensor, biceps brachii, triceps brachii, and upper trapezius muscles. Electromyography data were recorded during one repetition of 2 simulated surgical exercises via open surgery, MLS, and SLS. Participants completed a validated workload survey after each simulated surgical technique. Muscle activity and perceived workload were compared between surgical techniques with 1-way ANOVAs and Fisher's LSD post hoc tests.

RESULTS

Muscle activity during peg transfer was higher with MLS and SLS compared to simulated open surgery in the right and left forearm extensors (both P < .0001), right (P < .0001) and left biceps (P = .0005), right triceps (P = .0004), and right upper trapezius muscles (P = .0211). Similar results were found for the right and left forearm extensors (both P < .0001), right (P = .0381) and left (P = .0147) forearm flexors, right biceps (P < .0001), and right triceps (P = .0004) during a simulated suture task. Participants found laparoscopic techniques more mentally demanding, physically demanding, complex, and stressful compared to a simulated open surgical technique.

CONCLUSION

In veterinary students, average muscle activity and perceived workload were highest using MLS and SLS compared to an open surgical technique when performing simulated surgical exercises in a laparoscopic box trainer.

Muscle activity and hand motion in veterinarians performing laparoscopic training tasks with a box trainer

OBJECTIVE

To evaluate muscle activity and hand motion in veterinarians performing a standard set of laparoscopic training tasks.

SAMPLE

12 veterinarians with experience performing laparoscopic procedures.

PROCEDURES

Participants were asked to perform peg transfer, coordination, precision cutting, and suturing tasks in a laparoscopic box trainer. Activity of the right biceps brachii, triceps brachii, forearm flexor, forearm extensor, and trapezius muscles was analyzed by means of surface electromyography. Right hand movements and wrist angle data were registered through the use of a data glove, and risk levels for the wrist joint were determined by use of a modified rapid upper limb assessment (RULA) method. One-way repeated-measures ANOVA with a Bonferroni post hoc test was performed to compare values between tasks.

RESULTS

Activity in the biceps muscle did not differ significantly among the 4 tasks. Activity in the triceps, forearm flexor, and forearm extensor muscles was significantly higher during precision cutting than during the coordination task. Activity in the trapezius muscle was highest during the suturing task and did not differ significantly among the other 3 tasks. The RULA score was unacceptable (score, 3) for the coordination, peg transfer, and precision cutting tasks but was acceptable (score, 2) for the suturing task.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that the ergonomics of laparoscopic training depended on the tasks performed and the design of the instruments used. Precision cutting and suturing tasks were associated with the highest muscle activity. Acceptable wrist position, as determined with the RULA method, was found with the suturing task, which was performed with an axial-handled instrument.

Laparoscopic ovariectomy in dogs: comparison between laparoendoscopic single-site and three-portal access

This study was conducted to evaluate the feasibility and therapeutic safety of laparoendoscopic single-site ovariectomy (LESS-OVE) and 3-portal laparoscopic ovariectomy (Lap-OVE) in dogs. Ten female mixed breed dogs were included in the study. Dogs were divided into group 1 (LESS-OVE; n = 5) and group 2 (Lap-OVE; n = 5). All procedures were performed by laparoscopic-skilled surgeons, and the anesthetic protocol was the same for all patients. In both groups, the ovarian vascular pedicle and ligaments were transected using a bipolar vessel sealer/divider device. The mean total surgical time was slightly longer in LESS-OVE (36.6 ± 3.5 min) than Lap-OVE (32.0 ± 3.0 min); however, the differences were not significant. Perioperative complications were not reported in any group. Both laparoscopic techniques were shown to be equally feasible and safe for patients. However, surgeons found LESS-OVE to require more skill than Lap-OVE. Therefore, additional studies should be conducted to evaluate this novel approach in clinical veterinary practice, and a proper laparoscopic training program for veterinary surgeons should be developed.

Study of Individual Characteristic Abdominal Wall Thickness Based on Magnetic Anchored Surgical Instruments

BACKGROUND

Magnetic anchored surgical instruments (MASI), relying on magnetic force, can break through the limitations of the single port approach in dexterity. Individual characteristic abdominal wall thickness (ICAWT) deeply influences magnetic force that determines the safety of MASI. The purpose of this study was to research the abdominal wall characteristics in MASI applied environment to find ICAWT, and then construct an artful method to predict ICAWT, resulting in better safety and feasibility for MASI.

METHODS

For MASI, ICAWT is referred to the thickness of thickest point in the applied environment. We determined ICAWT through finding the thickest point in computed tomography scans. We also investigated the traits of abdominal wall thickness to discover the factor that can be used to predict ICAWT.

RESULTS

Abdominal wall at C point in the middle third lumbar vertebra plane (L3) is the thickest during chosen points. Fat layer thickness plays a more important role in abdominal wall thickness than muscle layer thickness. "BMI-ICAWT" curve was obtained based on abdominal wall thickness of C point in L3 plane, and the expression was as follow: f(x) = P1 × x 2 + P2 × x + P3, where P1 = 0.03916 (0.01776, 0.06056), P2 = 1.098 (0.03197, 2.164), P3 = -18.52 (-31.64, -5.412), R-square: 0.99.

CONCLUSIONS

Abdominal wall thickness of C point at L3 could be regarded as ICAWT. BMI could be a reliable predictor of ICAWT. In the light of "BMI-ICAWT" curve, we may conveniently predict ICAWT by BMI, resulting a better safety and feasibility for MASI.

Development of an arm support system to improve ergonomics in laparoscopic surgery: study design and provisional results

Background

Laparoscopic surgery (LS) induces physical stress to the surgeon that is associated with an increased prevalence of musculoskeletal pain and injury in the shoulder–neck region. The aim of this research project is to develop an arm support system (ASsyst) that reduces physical stress and is applicable to various laparoscopic interventions and operation room settings.

Methods

A systematic approach to develop an ASsyst started in October 2012 consisting of five consecutive steps. In step 1, 14 laparoscopic interventions were observed using subjective and objective measures to determine key indicators for the conception of an ASsyst in LS. In step 2, an expert workshop was held to find and evaluate solutions to generate concepts for a support system based on the results of step 1 and general methods. During the third step, prototypes of ASsyst were tested in an experimental setting. Steps 4 and 5 are currently in process and include the final development of the ASsyst using the most promising concept for the evaluation during simulated LS.

Results

Increased levels of physical stress were found in LS. Asymmetric strains were common. Three prototypes of ASsyst emerged from step 1 and 2. These prototypes were a cable construction with a noose for the lower arm, a support from below the elbow and a pneumatic vest supporting the upper arm. The experimental testing of these prototypes demonstrated reduced physical stress when compared to the unsupported environment. The support from below the elbow seemed to be the most practical in terms of implementation in various operation room settings and acceptance by surgeons. Step 4 and 5 are still in process.

Conclusions

Ergonomic problems have been identified in LS that could be addressed by an ASsyst. The concept of supporting the elbow from below has been found to be the most promising approach.