Intraoperative Ergonomic Assessment of Exoscopes versus Conventional DIEP Flap.

BACKGROUND: This study compared the ergonomics of surgeons during deep inferior epigastric perforator (DIEP) flap surgery using either baseline equipment (loupes, headlights, and an operating microscope) or an exoscope. Plastic surgeons may be at high risk of musculoskeletal problems. Recent studies indicate that adopting an exoscope may significantly improve surgeon postures and ergonomics. METHODS: Postural exposures, using inertial measurement units at the neck, torso, and shoulders, were calculated in addition to the surgeons' subjective physical and cognitive workload. An ergonomic risk score on a scale of 1 (lowest) to 4 (highest) was calculated for each of the postures observed. Data from 23 bilateral DIEP flap surgeries (10 baseline and 13 exoscope) were collected. RESULTS: The neck and torso risk scores decreased significantly during abdominal flap harvest and chest dissection, while right shoulder risk scores increased during the abdominal flap harvest for exoscope DIEP flap procedures compared with. Exoscope anastomoses demonstrated higher neck, right shoulder, and left shoulder risk scores. The results from the survey for the "surgeon at abdomen" showed that the usage of exoscopes was associated with decreased performance and increased mental demand, temporal demand, and effort. However, the results from the "surgeon at chest" showed that the usage of exoscopes was associated with lower physical demand and fatigue, potentially due to differences in surgeon preference. CONCLUSION: Our study revealed some objective evidence for the ergonomic benefits of exoscope; however, this is dependent on the tasks the surgeon is performing. Additionally, personal preferences may be an important factor to be considered in the ergonomic evaluation of the exoscope.

Physical pain and musculoskeletal discomfort in vascular surgeons.

OBJECTIVE: Work-related pain and disability have been reported in the literature among surgeons. This national survey was designed to identify the prevalence and severity of these symptoms in vascular surgeons. METHODS: A survey was emailed to the 2910 members of the Society for Vascular Surgery. Physical pain was evaluated based on body part, and type of vascular procedure performed using the Borg 0 to 10 pain scale. Wellness questions were also queried. RESULTS: A total of 775 of Society for Vascular Surgery members responded, with a 26.6% response rate. Retirees were excluded from the study (n = 39). Among those actively working (n = 736), surgeons have been practicing surgery, on average, for 17.2 ± 11.6 years, with a mean age of 51.4 ± 10.9 years, and 83.6% are male. After a full day of open surgery, the majority of the responding vascular surgeons are in a moderately strong amount of pain (mean score, 4.4 ± 2.3). After a full day of endovascular procedures, most vascular surgeons are in a moderately strong amount of pain (mean score, 3.9 ± 2.4). Pain after open surgery is greatest in the neck, and after endovascular surgery pain is highest in the lower back. Surgeons performing endovenous procedures demonstrated the lowest pain scores (2.0 ± 2.0). In total, 36.9% (242/655, 81 missing responses) have sought medical care for work-related pain, with 8.3% (61/736) taking time away from the operating room. Of those, 26.2% (193/736) report pain severe enough that it interferes with sleep. Seventy-two (10%) required surgery or other significant medical procedures. Of the 39 retirees, 26% ended their careers owing to physical disabilities from work-related pain. Out of the entire cohort, 52.7% (334/633,103 missing responses) feel that physical discomfort will affect the longevity of their careers. Additionally, we found that high work-related physical discomfort is significantly associated with burnout (burnout vs no burnout; P < .0001). CONCLUSIONS: Our study shows that the majority of practicing vascular surgeons responding to the survey are in pain after a day of operating. Addressing work-related pain serves to improve the lives and careers of vascular surgeons and enhance surgical longevity.

Vascular surgeon wellness and burnout: A report from the Society for Vascular Surgery Wellness Task Force.

INTRODUCTION: Physician burnout has been linked to medical errors, decreased patient satisfaction, and decreased career longevity. In light of the increasing prevalence of cardiovascular disease, vascular surgeon burnout presents a legitimate public health concern owing to the impact on the adequacy of the vascular surgery workforce. The aims of this study were to define the prevalence of burnout among practicing vascular surgeons and identify factors that contribute to burnout to facilitate future Society for Vascular Surgery (SVS) initiatives to mitigate this crisis. METHODS: In 2018, active SVS members were surveyed electronically and confidentially using the Maslach Burnout Inventory. The survey was tailored to explore specialty-specific issues, and to capture demographic and practice-related characteristics. Emotional exhaustion (EE) and depersonalization (DP) were analyzed as dimensions of burnout. Consistent with convention, surgeons with a high score on the DP and/or EE subscales of the Maslach Burnout Inventory were considered to have at least one manifestation of professional burnout. Risk factors associated with symptoms of burnout were identified using bivariate analyses (χ2, Kruskal-Wallis). Multivariate logistic regression models were developed to identify independent risk factors for burnout. RESULTS: Of 2905 active SVS members, 960 responded to the survey (34% participation rate). After excluding retired surgeons and incomplete submissions, responses from 872 practicing vascular surgeons were analyzed. The mean age was 49.7 ± 11.0 years; the majority of respondents (81%) were male. Primary practice settings were academic (40%), community practice (41%), veteran's hospital (3.3%), active military practice (1.5%), or other. Years in practice averaged 15.7 ± 11.7. Overall, 41% of respondents had at least one symptoms of burnout (ie, high EE and/or high DP), 37% endorsed symptoms of depression in the past month, and 8% indicated they had considered suicide in the last 12 months. In unadjusted analysis, factors significantly associated with burnout (P < .05) included clinical work hours, on-call frequency, electronic medical record and documentation requirements, work-home conflict, and work-related physical pain. On multivariate analysis, age, work-related physical pain and work-home conflict were independent predictors for burnout. CONCLUSIONS: Symptoms of burnout and depression are common among vascular surgeons. Advancing age, work-related physical pain, and work-home conflict are independent predictors for burnout among vascular surgeons. Efforts to promote vascular surgeon well-being must address specialty-specific challenges, including the high prevalence of work-home conflict and occupational factors that contribute to work-related pain.

Sitting versus standing makes a difference in musculoskeletal discomfort and postural load for surgeons performing vaginal surgery.

INTRODUCTION AND HYPOTHESIS: We compared musculoskeletal discomfort and postural load among surgeons in sitting and standing positions during vaginal surgery. MATERIALS AND METHODS: Assessment of discomfort and posture of the primary surgeons in both positions was performed at two institutions. The primary outcome was an increase in body discomfort score after surgery as determined from subjective responses using validated tools. The secondary outcome was the percentage of time spent in awkward body postures measured objectively and stratified into awkward postures for neck, trunk, and bilateral shoulder angles. Variables were compared between sitting and standing positions using Fisher's exact test for primary outcomes and Wilcoxon rank-sum test for secondary outcomes. RESULTS: Data were collected for 24 surgeries from four surgeons in sitting position and nine surgeries from nine surgeons in standing position. The standing surgeons reported a significant increase in discomfort postoperatively for bilateral wrists, thighs, and lower legs compared with the sitting surgeons. The median percentage of time spent in awkward postures was significantly lower for the trunk in the standing versus sitting position (median 0.3% vs 58.8%, p < 0.001) but was significantly higher for both shoulders in the standing versus the sitting position (right shoulder: median 17.8% vs 0.3%, p = 0.003; left shoulder: median 7.4% vs 0.2%, p = 0.003). CONCLUSION: Surgeons reported more discomfort in when performing vaginal surgery while standing. The postural load was worse for trunk but favorable for bilateral shoulders when seated. Such differences may impact a surgeon's decision to perform vaginal surgery seated rather than standing.

Work-Related Musculoskeletal Discomfort and Injury in Microsurgeons.

BACKGROUND: Long surgical procedures with loupe magnification and microscopes may put microsurgeons at an increased risk of musculoskeletal discomfort. Identifying the prevalence and impact of work-related musculoskeletal discomfort may guide preventive strategies to prolong well-being, job satisfaction, and career duration. METHODS: An online 29-question survey was designed to evaluate work-related musculoskeletal discomfort. The survey was created and distributed electronically through a private survey research center and was sent to the members of the American Society for Reconstructive Microsurgery. RESULTS: There were 117 respondents (16.7% response rate): 80% were men; 69% were aged 31 to 50 years; and 68% were in academic practice. On a scale of 0 to 10 (0, no pain and 10, worst pain), the median for work-related musculoskeletal discomfort for surgery without loupes or microscope was 2; with loupes, 4; and with a microscope, 5. Pain was most common in the neck. Half of the surgeons reported pain within 4 hours of surgery, and 57% feared that pain would influence future surgical performance. Surgeon discomfort affected posture (72%), stamina (36%), sleep (29%), relationships (25%), concentration (22%), and surgical speed (19%). Tremor caused by the discomfort occurred in 8%. Medical treatment for discomfort was sought by 29%. Time off work for treatment occurred for 8%. CONCLUSION: Work-related musculoskeletal discomfort can affect many aspects of a microsurgeon's life and has the potential to limit a surgeon's ability to operate. Therefore, more emphasis is needed in the surgical community on the important issues of occupational health and surgical ergonomics for microsurgeons.

The influence of stress responses on surgical performance and outcomes: Literature review and the development of the surgical stress effects (SSE) framework.

BACKGROUND: Surgical adverse events persist despite several decades of system-based quality improvement efforts, suggesting the need for alternative strategies. Qualitative studies suggest stress-induced negative intraoperative interpersonal dynamics might contribute to performance errors and undesirable patient outcomes. Understanding the impact of intraoperative stressors may be critical to reducing adverse events and improving outcomes. DATA SOURCES: We searched MEDLINE, psycINFO, EMBASE, Business Source Premier, and CINAHL databases (1996-2016) to assess the relationship between negative (emotional and behavioral) responses to acute intraoperative stressors and provider performance or patient surgical outcomes. RESULTS/CONCLUSIONS: Drawing on theory and evidence from reviewed studies, we present the Surgical Stress Effects (SSE) framework. This illustrates how emotional and behavioral responses to stressors can influence individual surgical provider (e.g. surgeon, nurse) performance, team performance, and patient outcomes. It also demonstrates how uncompensated intraoperative threats and errors can lead to adverse events, highlighting evidence gaps for future research efforts.

"The Jackson Table Is a Pain in the ": A Qualitative Study of Providers' Perception Toward a Spinal Surgery Table.

OBJECTIVE: The aim of this study was to define health care providers' perceptions toward prone patient positioning for spine surgery using the Jackson Table, which has not been hitherto explored. METHODS: We analyzed open-ended questionnaire data and interviews conducted with the spine surgical team regarding the current process of spinal positioning/repositioning using the Jackson Table. Participants were asked to provide an open-ended explanation as to whether they think the current process of spinal positioning/repositioning is safe for the staff or patients. Follow-up qualitative interviews were conducted with 11 of the participants to gain an in-depth understanding of the challenges and safety issues related to prone patient positioning. RESULTS: Data analysis resulted in 6 main categories: general challenges with patient positioning, role-specific challenges, challenges with the Jackson Table and the "sandwich" mechanism, safety concerns for patients, safety concerns for the medical staff, and recommendations for best practices. CONCLUSIONS: This study is relevant to everyday practice for spinal surgical team members and advances our understanding of how surgical teams qualitatively view the current process of patient positioning for spinal surgery. Providers recommended best practices for using the Jackson Table, which can be achieved through standardized practice for transfer of patients, educational tools, and checklists for equipment before patient transfer and positioning. This research has identified several important practice opportunities for improving provider and patient safety in spine surgery.

The use of patient factors to improve the prediction of operative duration using laparoscopic cholecystectomy.

BACKGROUND: Reliable prediction of operative duration is essential for improving patient and care team satisfaction, optimizing resource utilization and reducing cost. Current operative scheduling systems are unreliable and contribute to costly over- and underestimation of operative time. We hypothesized that the inclusion of patient-specific factors would improve the accuracy in predicting operative duration. METHODS: We reviewed all elective laparoscopic cholecystectomies performed at a single institution between 01/2007 and 06/2013. Concurrent procedures were excluded. Univariate analysis evaluated the effect of age, gender, BMI, ASA, laboratory values, smoking, and comorbidities on operative duration. Multivariable linear regression models were constructed using the significant factors (p < 0.05). The patient factors model was compared to the traditional surgical scheduling system estimates, which uses historical surgeon-specific and procedure-specific operative duration. External validation was done using the ACS-NSQIP database (n = 11,842). RESULTS: A total of 1801 laparoscopic cholecystectomy patients met inclusion criteria. Female sex was associated with reduced operative duration (-7.5 min, p < 0.001 vs. male sex) while increasing BMI (+5.1 min BMI 25-29.9, +6.9 min BMI 30-34.9, +10.4 min BMI 35-39.9, +17.0 min BMI 40 + , all p < 0.05 vs. normal BMI), increasing ASA (+7.4 min ASA III, +38.3 min ASA IV, all p < 0.01 vs. ASA I), and elevated liver function tests (+7.9 min, p < 0.01 vs. normal) were predictive of increased operative duration on univariate analysis. A model was then constructed using these predictive factors. The traditional surgical scheduling system was poorly predictive of actual operative duration (R 2 = 0.001) compared to the patient factors model (R 2 = 0.08). The model remained predictive on external validation (R 2 = 0.14).The addition of surgeon as a variable in the institutional model further improved predictive ability of the model (R 2 = 0.18). CONCLUSION: The use of routinely available pre-operative patient factors improves the prediction of operative duration during cholecystectomy.

Intraoperative workload in robotic surgery assessed by wearable motion tracking sensors and questionnaires.

BACKGROUND: The introduction of robotic technology has revolutionized radical prostatectomy surgery. However, the potential benefits of robotic techniques may have trade-offs in increased mental demand for the surgeon and the physical demand for the assisting surgeon. This study employed an innovative motion tracking tool along with validated workload questionnaire to assess the ergonomics and workload for both assisting and console surgeons intraoperatively. METHODS: Fifteen RARP cases were collected in this study. Cases were performed by 10 different participants, six primarily performed console tasks and four primarily performed assisting tasks. Participants had a median 12 (min-3, max-25) years of surgical experience. Both console and assisting surgeons performed robotic prostatectomy cases while wearing inertial measurement units (IMUs) that continuously track neck, shoulder, and torso motion without interfering with the sterile environment. Postoperatively, participants completed a workload questionnaire (SURG-TLX) and a body part discomfort questionnaire. RESULTS: Twenty-six questionnaires were completed from 13 assisting and 13 console surgeons over the 15 cases. Postoperative pain was reported highest for the right shoulder and neck. Mental demands were 41 % higher for surgeons at the console than assisting (p < 0.05), while physical demands were not significantly different. Assisting surgeons worked in demanding neck postures for 58 % of the procedure compared to 24 % for the console surgeon (p < 0.01). Surgeons at the console were primarily static and showed 2-5 times fewer movements than assisting surgeons (p < 0.01). CONCLUSIONS: Postures were more ergonomic during console tasks than when assisting by the bedside; however, the console may constrain postures leading to static loads that have been associated with musculoskeletal symptoms for the neck, torso, and shoulders. The IMU sensors were effective at quantifying ergonomics in robotic prostatectomies, and these methods and findings have broad applications to other robotic procedures.

Effect of chair types on work-related musculoskeletal discomfort during vaginal surgery.

BACKGROUND: Evidence supports that surgeons are at high risk for work-related musculoskeletal disorders. OBJECTIVE: The objective of the study was to compare the effect of different chairs on work-related musculoskeletal discomfort for surgeons during vaginal operations. STUDY DESIGN: This crossover study randomly assigned 4 surgeons to 4 chair types using a 4 × 4 Latin square model: a conventional round stool, a round stool with a backrest, a saddle chair with a backrest, and a Capisco chair. Subjective assessments of surgeon discomfort were performed with a validated body discomfort survey, and workload was assessed with the surgical task load index. The objective postural load was quantified with inertial measurement units of the modified rapid upper limb assessment limits. Subjective and objective assessments of chair comfort were performed with an 11 point scale and seat interface pressure-mapped distributions, respectively. The primary outcome was the difference in body discomfort scores between pre- and postsurgery measurements. Secondary outcomes were the differences in chair comfort scores, postural load, and seating interface pressure-mapped distribution. For each outcome, comparisons among the chair types were based on fitting a linear mixed model that handled the surgeon as a random effect and the chair type as a fixed effect. RESULTS: Data were collected for 48 vaginal procedures performed for pelvic organ prolapse. Mean (SD) duration of surgery was 122.3 (25.1) minutes. Surgeons reported body discomfort during 31 procedures (67.4%). Subjective increase in discomfort from the preoperative state was noted most commonly in the lower back (n = 14, 30.4%), followed by right shoulder (n = 12, 26.1%), upper back (n = 8, 17.4%), hips and buttocks (n = 7, 15.2%), left shoulder (n = 6, 13.0%), right or left thigh (n = 6, 13.0%), and neck (n = 6, 13.0%). Pre- and postsurgery body discomfort scores did not differ with respect to chair type. Chair discomfort scores for the round stool and the saddle chair were significantly higher than the round stool with backrest and the Capisco chair (P < .001). Although the average modified rapid upper limb assessment postural scores showed moderate to high musculoskeletal risk of neck and shoulder discomfort across the 4 surgeons; chair type did not affect postural scores. The saddle chair had significantly reduced dispersion of seated pressure vs the round stool with backrest (P ≤ .001), depicted by the number of cells with pressure values >5 mm Hg. An increased dispersion of pressure across the chair surface was associated with increased comfort (Spearman correlation, 0.40, P = .006). CONCLUSION: Musculoskeletal strain and associated discomfort for surgeons are very high during vaginal operations. Chair type can affect comfort, and chairs with more uniform distribution and fewer pressure points are more comfortable. However, the chair type used in surgery did not influence the musculoskeletal postural load findings.

Impact of patient factors on operative duration during laparoscopic cholecystectomy: evaluation from the National Surgical Quality Improvement Program database.

BACKGROUND: Patient factors impact laparoscopic cholecystectomy (LC) difficulty, specifically operative duration. This study quantifies the impact of patient factors on LC duration. METHODS: The national surgery database (American College of Surgeons National Surgical Quality Improvement Program) was reviewed for all elective LC for biliary colic from 2005 to 2013. Multivariate general linear model and logistic regression were used to evaluate patient factors as predictors of operative duration greater than 60 minutes, adjusted for resident involvement and cholangiography. RESULTS: A total of 24,099 LC met inclusion criteria. Regression analysis found procedure duration greater than 60 minutes was less likely for patients age greater than 40 and less than 30 (P < .001) and more likely for men (P < .05), body mass index (BMI) greater than 30 compared with BMI 18.5 to 24.9 (P < .05), abnormal liver function test (LFT) (P < .05), and higher ASA class (P < .05). Smoking, cardiovascular disease, chronic obstructive pulmonary disease, diabetes, and abnormal white blood cell count were not significant predictors. CONCLUSIONS: Higher BMI, younger age, male gender, higher ASA, and abnormal LFTs are possible predictors of prolonged LC duration and can aid in operating room scheduling and utilization.

Quantifying Intraoperative Workloads Across the Surgical Team Roles: Room for Better Balance?

BACKGROUND: Surgical performance, provider health, and patient safety can be compromised when workload demands exceed individual capability on the surgical team. The purpose of this study is to quantify and compare intraoperative workload among surgical team members. METHODS: Observations were conducted for an entire surgical day for 33 participating surgeons and their surgical team at one medical institution. Workload (mental, physical, case complexity, distractions, and case difficulty) was measured for each surgical team member using questions from validated questionnaires. Statistical analyses were performed with a mixed effects model. RESULTS: A total of 192 surgical team members participated in 78 operative cases, and 344 questionnaires were collected. Procedures with high surgeon mental and physical workload included endovascular and gastric surgeries, respectively. Ratings did not differ significantly among surgeons and residents, but scrub nurses physical demand ratings were 14-22 (out of 100) points lower than the surgeons, residents, and surgical assistants. Residents reported the highest mental workload, averaging 19-24 points higher than surgical assistants, scrub nurses, and circulating nurses. Mental and physical demands exceeded 50 points 28-45 % of the time for surgeons and residents. Workload did not differ between minimally invasive and open techniques. CONCLUSION: The workload questionnaires are an effective tool for quantifying intraoperative workload across the surgical team to ensure mental and physical demands do not exceed thresholds where performance may decrease and injury risk increase. This tool has the potential to measure the safety of current procedures and drive design of workload interventions.

Impact of novel shift handle laparoscopic tool on wrist ergonomics and task performance.

BACKGROUND: Laparoscopic tool handles causing wrist flexion and extension more than 15° from neutral are considered "at risk" for musculoskeletal strain. Therefore, this study measured the impact of laparoscopic tool handle angles on wrist postures and task performance. METHODS: Eight surgeons performed standard and modified Fundamentals of Laparoscopic Surgery (FLS) tasks with laparoscopic tools. Tool A had three adjustable handle angle configurations, i.e., in-line 0° (A0), 30° (A30), and pistol-grip 70° (A70). Tool B was a fixed pistol-grip grasper. Participants performed FLS peg transfer, inverted peg transfer, and inverted circle cut with each tool and handle angle. Inverted tasks were adapted from standard FLS tasks to simulate advanced tasks observed during abdominal wall surgeries, e.g., ventral hernia. Motion tracking, video analysis, and modified NASA-TLX workload questionnaires were used to measure postures, performance (e.g., completion time and errors), and workload. RESULTS: Task performance did not differ between tools. For FLS peg transfer, self-reported physical workload was lower for B than for A70, and mean wrist postures showed significantly higher flexion for in-line than for pistol-grip tools (B and A70). For inverted peg transfer, workload was higher for all configurations. However, less time was spent in at-risk wrist postures for in-line (47 %) than for pistol-grip (93-94 %), and most participants preferred Tool A. For inverted circle cut, workload did not vary across configurations, mean wrist posture was 10° closer to neutral for A0 than B, and median time in at-risk wrist postures was significantly less for A0 (43 %) than for B (87 %). CONCLUSION: The best ergonomic wrist positions for FLS (floor) tasks are provided by pistol-grip tools and for tasks on the abdominal wall (ventral surface) by in-line handles. Adjustable handle angle laparoscopic tools can reduce ergonomic risks of musculoskeletal strain and allow versatility for tasks alternating between the floor and ceiling positions in a surgical trainer without impacting performance.

Surgical never events and contributing human factors.

INTRODUCTION: We report the first prospective analysis of human factors elements contributing to invasive procedural never events by using a validated Human Factors Analysis and Classification System (HFACS). METHODS: From August 2009 to August 2014, operative and invasive procedural "Never Events" (retained foreign object, wrong site/side procedure, wrong implant, wrong procedure) underwent systematic causation analysis promptly after the event. Contributing human factors were categorized using the 4 levels of error causation described by Reason and 161 HFACS subcategories (nano-codes). RESULTS: During the study, approximately 1.5 million procedures were performed, during which 69 never events were identified. A total of 628 contributing human factors nano-codes were identified. Action-based errors (n = 260) and preconditions to actions (n = 296) accounted for the majority of the nano-codes across all 4 types of events, with individual cognitive factors contributing one half of the nano-codes. The most common action nano-codes were confirmation bias (n = 36) and failed to understand (n = 36). The most common precondition nano-codes were channeled attention on a single issue (n = 33) and inadequate communication (n = 30). CONCLUSION: Targeting quality and interventions in system improvement addressing cognitive factors and team resource management as well as perceptual biases may decrease errors and further improve patient safety. These results delineate targets to further decrease never events from our health care system.

The effect of a lightweight massage system in a car seat on comfort and electromyogram.

OBJECTIVE: The objective of this study was to determine the effect of a lightweight low-intensity massage system (LWMAS) in a car seat on the electromyogram (EMG) of the neck and shoulder muscles and on the comfort experience during driving. METHODS: Two experiments were performed during driving with and without the active LWMAS in the seat. Subjective measurements were taken, in which the comfort experience was recorded for 20 participants driving a prescribed path around Munich for 120 minutes. Then objective (surface EMG above the rhomboideus and trapezius muscles) measurements and subjective measurements of the comfort experience were recorded over 7 laps on a test track for 24 participants. RESULTS: The comfort was higher, and the EMG was significantly lower in the trapezius area while driving with the LWMAS. CONCLUSION: Despite the fact that the LWMAS system is lightweight, has low intensity, and might have had a smaller effect, similar effects to previous studies with heavier systems were found, indicating that this massage system increases comfort and reduces muscle activity during driving as well.

Socio-Technical Systems Analysis in Health Care: A Research Agenda.

Given the complexity of health care and the 'people' nature of healthcare work and delivery, STSA (Sociotechnical Systems Analysis) research is needed to address the numerous quality of care problems observed across the world. This paper describes open STSA research areas, including workload management, physical, cognitive and macroergonomic issues of medical devices and health information technologies, STSA in transitions of care, STSA of patient-centered care, risk management and patient safety management, resilience, and feedback loops between event detection, reporting and analysis and system redesign.

Effect of visual feedback on surgical performance using the da Vinci surgical system.

BACKGROUND: Robotic surgical systems quantify human movements in terms of position, velocity, and time span. This information can be used to objectively assess surgical skill. The aim of this study was to test the effects of three-dimensional vs. two-dimensional visualization on performance using the da Vinci Surgical System (Intuitive Surgical, Sunnyvale, CA). MATERIALS AND METHODS: The movements of novice and expert surgeons were recorded using the da Vinci Surgical System for a two-handed task in two visual environments (two-dimensional and three-dimensional). Data were analyzed to investigate the effect of visual feedback on performance. RESULTS: Velocities and task completion times were significantly different for novices and experts (P < 0.05) for all velocity parameters in both visual conditions. Additionally, there was a significant difference between two-dimensional and three-dimensional times for novices (P < 0.05). Novices were idle significantly longer in two-dimensional than in three-dimensional visual input (P = 0.037), and overall, novices were idle longer than experts for both visual conditions (P = 0.001). CONCLUSION: Three-dimensional visual input allows novice surgeons to perform tasks with higher velocities, less idle time, and greater economy of motion. However, three-dimensional visual input provides no significant enhancement of performance for expert surgeons.

A comparison of muscular activity during single and double mouse clicks.

Work-related musculoskeletal disorders (WMSDs) in the neck/shoulder region and the upper extremities are a common problem among computer workers. Occurrences of motor unit (MU) double discharges with very short inter-firing intervals (doublets) have been hypothesised as a potential additional risk for overuse of already exhausted fibres during long-term stereotyped activity. Doublets are reported to be present during double-click mouse work tasks. A few comparative studies have been carried out on overall muscle activities for short-term tasks with single types of actions, but none on occurrences of doublets during double versus single clicks. The main purpose of this study was to compare muscle activity levels of single and double mouse clicks during a long-term combined mouse/keyboard work task. Four muscles were studied: left and right upper trapezius, right extensor digitorum communis (EDC) and right flexor carpi ulnaris. Additionally, MU activity was analysed through intramuscular electromyography in the EDC muscle for a selection of subjects. The results indicate that double clicking produces neither higher median or 90th percentile levels in the trapezius and EDC muscles, nor a higher disposition for MU doublets, than does single clicking. Especially for the 90th percentile levels, the indications are rather the opposite (in the EDC significantly higher during single clicks in 8 of 11 subjects, P < 0.05). Although it cannot be concluded from the present study that double clicks are harmless, there were no signs that double clicks during computer work generally constitute a larger risk factor for WMSDs than do single clicks.