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

Abstract

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.

Fig. 1

Setup of the video analysis measurements in the operating room

Fig. 2

Electrical activity of the trapezius muscle during laparoscopic surgery in gynecology and urology. The electrical activity is given as the percent of the reference contraction performed with a 90° ante-version of both straight arms holding a 2-kg dumbbell in each hand

Fig. 3

Frequency distribution of the arm abduction angle in gynecological laparoscopic surgery

Fig. 4

Examples of representative body posture during laparoscopic surgery

Fig. 5

Prototypes of three different concepts of a support system

Fig. 6

Electrical activity of the trapezius muscle performing the simulated laparoscopic surgery with and without prototypes of different supporting systems (simulated laparoscopic surgery was performed predominantly with the right arm). The electrical activity is given as a percent of the reference contraction which is performed with a 90° ante-version of both straight arms holding a 2-kg dumbbell in each hand