Work Breaks During Simulated Minimally Invasive Surgery

University Hospital Tuebingen21 enrolled

Overview

Minimally invasive surgeons have a prevalence of work-related musculoskeletal complaints of up to 86% due to the exposure to static loading, awkward postures, work pressure, and patient's wellbeing. Researchers have developed postural interventions to counteract the prevalence of musculoskeletal complaints and disorders, such as robot-assisted surgeries, arm-support systems, and rotatable handle pieces. An alternative intervention is to implement work breaks during the surgeries, which has shown to give promising results including that surgery duration does not prolong. The aim of the current study is to simulate 90-min laparoscopic surgery activities in the laboratory and compare two intervention situations with the control situation. The control situation is without work breaks. The two intervention situations include 2.5-min breaks provided two times, i.e. after every 30-min work period, which are passive (rest) or active (targeted mobilization exercises). The assessment is based on changes in muscular activity on the back and upper extremities, back and upper extremity postures, feelings of discomfort, and work performance.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

NONE

Enrollment

Conditions

Work-break Schedules

Interventions

Eligibility

Sex: ALLMin age: 18 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * (Student) surgeons, who are familiar with laparoscopic procedures and / or simulated laparoscopic procedures; * Be able to perform the Peg-Transfer task (Simulab, Seattle, WA, USA) within 3 minutes; * The participant will give her/his voluntary informed consent after receiving oral and written information of the content and goal of the study. Exclusion Criteria: * (Student) surgeons who are not familiar with laparoscopic procedures and / or simulated laparoscopic procedures; * Not able to perform the Peg-Transfer task within 3 minutes; * People under the influence of intoxicants, analgesics, or muscle relaxants; * Alcohol abuse; * People with cardiovascular diseases; * People with a heart pacemaker; * People with a disability who, due to their restriction at a workplace of this kind, will not be able to participate; * People with Diabetes Mellitus; * People with severe muscle contractions of the lower extremities, back or arms; * People with acute ailments or pain, which make(s) them unable to participate; * People who are unable to complete the examination program due to language or cognitive obstacles; * Depending on the degree of severity, people with diseases of the veins and joints of the lower extremities, spine, muscle disorders, symptomatic neurological-psychiatric diseases, acute pain syndromes, maladies or other current diseases.

Outcomes

Primary Outcomes

Rating of perceived discomfort

Discomfort will be assessed using an 11-point numeric rating scale, ranging from 0 (no discomfort at all) to 10 (maximally imaginable discomfort). It will be assessed directly before and directly after each experimental condition.

Time frame: Change from baseline (0 min) to directly after (90 min) each experimental condition

Secondary Outcomes

Root-mean-square of electrical muscle activity recordings using electromyography

Selected target muscles in the arms (deltoid acromialis, extensor digitorum, flexor carpi radialis), shoulder (trapezius descendens) and back (erector spinae lumbalis) will be continuously recorded with electromyography. From the electromyographic signal, the root-mean-square will be calculated and averaged over the time period in each experimental condition.

Time frame: Average root-mean-square of muscle activity over the time period running from baseline (0 min) to directly after (90 min) each experimental condition

Median power frequency of electrical muscle activity recordings using electromyography

Selected target muscles in the arms (deltoid acromialis, extensor digitorum, flexor carpi radialis), shoulder (trapezius descendens) and back (erector spinae lumbalis) will be continuously recorded with electromyography. From the electromyographic signal, the median power frequency will be calculated and averaged over the time period in each experimental condition.

Time frame: Average median power frequency f muscle activity over the time period running from baseline (0 min) to directly after (90 min) each experimental condition

Posture of the spine / back

Using gravimetric position sensors, the curvature of the back will be recorded as well as the head position and movement with respect to the trunk. Recordings are continuous and average angles (kyphosis, lordosis, neck angle) will be calculated per time period.

Time frame: Average posture over time period baseline (0 min) to end (90 min) of each experimental condition

Heart rate

Continuous recording electrocardiography allows calculating the heart rate, a parameter reflecting the central stress state of the participant. The average heart rate will be calculated per time period.

Time frame: Average heart activity over time period baseline (0 min) to end (90 min) of each experimental condition

Work performance

Using the Peg-Transfer Board (Simulab, Seattle, WA, USA), subjects will perform this task for exaclty 1 minute. Time is recorded after one repetition is finished and final performance for the overall minute is recorded as well.

Time frame: Change from baseline (0 min) to directly after (90 min) each experimental condition

Workload

Using the Hart and Staveland's NASA Task Load Index (TLX) method, workload is assessed for 6 dimensions where participants put a cross on one of the 21 lines on the 21-point scales, which range from left (very satisfied; way too much; much to short; clearly increased) to right (very unsatisfied; way too few; much to long; clearly reduced).

Time frame: Assessed at 90 min, directly after each experimental condition

Participant evaluation

Self-developed questionnaire assessing aspects of applicability and acceptability of the tested interventions in the field. All questions will be multiple choice questions, resulting in categorical variables (scales ranging from 1 \[very satisfied / true\] to 4 \[very unsatisfied / not true\]).

Time frame: Assessed at 90 min, directly after the experimental conditions with intervention