ارزیابی ارگونومیک اسکلتی و حرکات محوری اندام فوقانی جراحان در حین عمل جراحی باز و لاپاروسکوپی

Background: Many surgeons have complained of fatigue and musculoskeletal pain after laparoscopic surgery. We evaluated differences in surgeons’ axial skeletal and upper extremity movements during laparoscopic and open operations. Methods: Five surgeons were videotaped performing 16 operations (8 laparoscopic and 8 open) to record their neck, trunk, shoulder, elbow, and wrist movements during the first hour of surgery. We also compared postprocedural complaints of pain, stiffness, or numbness between the two groups. Results: Compared with surgeons performing open surgery, surgeons performing laparoscopic surgery exhibited less lateral neck flexion; less trunk flexion; more internal rotation of the shoulders; more elbow flexion; more wrist supination and wrist ulnar and radial deviation. There was a trend of more shoulder stiffness after laparoscopic operations than after open operations. Conclusions: Laparoscopic surgery involves a more static posture of the neck and trunk, but more frequent awkward movements of the upper extremities than open surgery. Ergonomic changes in the operating room environment and instrument design could ease the physical stress imposed on surgeons during laparoscopic operation

We videotaped five surgeons performing eight laparoscopic and eight open operations. Surgeons’ neck, back, and upper extremity movements exhibited during the laparoscopic operations were compared with those during the open operations. The video provided only a single frontal view of the surgeon’s head to pelvis. Only the first hour of surgery was videotaped and analyzed due to limited time for review of the tapes. Immediately after the surgery, one of two physical therapy students (CP, RDV) from the Program of Physical Therapy at California State University, Sacramento, administered a questionnaire to each surgeon. The questionnaire asked for the presence of, the location of (neck, back, shoulder, hand/wrist on a drawing of a human body), and the severity of pain, stiffness, or numbness on a scale of mild, moderate, and severe. The physical therapy students reviewed all videotapes and recorded the numbers of neck, trunk, shoulder, elbow, and wrist movements using predefined criteria developed by the Department of Physical Therapy. A single specific movement of the neck, back, shoulder, elbow, or wrist was defined as a deviation of the body posture from the neutral upright body position and included its return to the neutral body position. For example, a single movement of wrist supination was any rotational movement from the neutral position going in the direction of supination and back to the neutral position. Neck movements were categorized as flexion, extension, lateral flexion, and rotation. Trunk movements were categorized as flexion and rotation. Shoulder movements were categorized as flexion, abduction, and internal rotation. For elbow movements, the total number of flexion movements (including both <90° and >90°) were counted. Wrist movements were recorded as pronation, supination, flexion, extension, ulnar deviation, and radial deviation. Data were given as the mean number of specific movements ± standard deviation for each body part for both laparoscopic and open operations. Comparison of the number of movements during laparoscopic and open surgery was performed using unpaired t tests or Mann-Whitney U tests for nonparametric data. The percentage of surgeons in the two groups with postoperative pain and stiffness was compared using Fisher’s exact tests. Statistical evaluations were performed using standardized software (Stat-View, SAS Institute Inc., Cary, North Carolina). A P value less than 0.05 was considered significant.

Surgeons are at risk for development of musculoskeletal fatigue during both open and laparoscopic operations [1], [2] and [7]. A correlation has been reported between musculoskeletal stress and prolonged static head-bent and back-bent positions among surgeons and scrub nurses [7]. A high rate of disability from cervicobrachial disorders also have been reported among dentists, presumably related to their working postures [8]. In general, risk factors for musculoskeletal injury include awkward body postures, frequent awkward repetitive movements of the upper extremities, and prolonged static head and back postures [1]. Both open and laparoscopic surgical operations are performed with the surgeon in a standing, upright position; however, owing to the constraint of the abdominal port positions during laparoscopic surgery, laparoscopic surgeons sometimes adopt awkward body positions and make certain awkward repetitive upper extremity movements to accomplish their operative tasks. Neck pain and stiffness are frequent complaints after laparoscopic operations. The Society of American Gastrointestinal Endoscopic Surgeons (SAGES) Task Force on Ergonomics [9] reported an 8% to 12% incidence of pain in the neck and upper extremities and a 9% to 18% incidence of stiffness in these areas among 149 surgeons responding to a questionnaire of body part discomfort after laparoscopic operations. Our study demonstrated a greater frequency of neck flexion movements during laparoscopic surgery than during open surgery. The higher frequency of neck flexions may occur because laparoscopic surgeons must look between the monitor and the surgical field. In addition, laparoscopic surgeons had significantly fewer lateral neck flexion movements, which was likely due to the fixed position of the video display. Static back postures also have been implicated to increase surgeons’ back pain [1]. Kant et al [7] demonstrated that static body postures were frequently displayed by surgeons and scrub nurses during open surgery, with up to 54% of the time spent in a forward, bent-head stance and 27% of the time spent in a back twisted and bent stance. Laparoscopic surgery seems to demand an even higher proportion of static back postures. Rademacher et al [10] concluded that 70% of intraoperative work postures during laparoscopic procedures were substantially static, and Berguer et al [2] observed that laparoscopic surgeons often held a head-straight, back-straight stance. Our study concurred with these findings and demonstrated that surgeons performing laparoscopic surgery have significantly less back flexion movements than surgeons performing open surgery. Shoulder movements during laparoscopic surgery have not been extensively evaluated. Musculoskeletal stress upon the shoulder during laparoscopic operations is related in part to the operating room table height and the design of laparoscopic instruments. During laparoscopic operations, the shoulder tends to be in a slightly raised position. In addition, the fixed position of the access ports limits the surgeons’ arm and hand movements to only 4 degrees compared with the general 6 degrees of freedom during open operations [10]. The combination of these factors requires laparoscopic surgeons to make awkward movements such as internal rotations of the shoulder to compensate for the limitations of the abdominal ports. Our study documented a higher frequency of internal rotations of the shoulder during laparoscopic operations than during open operations. Though not at the level of statistical significance, there was a trend toward a higher number of surgeons complaining of shoulder stiffness after laparoscopic than after open surgery (50% versus 0%, respectively). Wrist and hand fatigue has been reported after laparoscopic operations [3]. Factors contributing to wrist and hand fatigue include the use of the laparoscopic instruments and awkward wrist movements during laparoscopic operations. Laparoscopic instruments are longer than open instruments and their fulcrum point is at the port site of the abdominal wall. Therefore, laparoscopic instruments are characterized by an unfavorable force transmission from the handle to the tip, such that laparoscopic surgeons must use four to six times more force to complete the same task as in open surgery. As a result, laparoscopic instruments require significantly greater peak and total muscle effort of the surgeon’s forearm and thumb than open instruments, leading to additional fatigue [1] and [7]. Berguer et al [9] demonstrated that surgeons’ forearm electromyograms increased when a laparoscopic grasper was used rather than a standard hemostat. In our study, we confirmed that laparoscopic surgeons exhibited more awkward wrist movements (wrist supination, ulnar, and radial deviations) than surgeons performing open surgery. We think this is related in part to our laparoscopic suturing technique. Laparoscopic suturing was performed using the Endo Stitch (United States Surgical Corp., Norwalk, Connecticut). The Endo Stitch facilitates laparoscopic suturing, but its design requires the surgeon to perform many awkward repetitive wrist movements that are not performed routinely in conventional suturing. Our study has limitations. The set-up of the video camera was not ideal. At times, the assistant surgeon, scrub nurses, and surgical drapes blocked the view of the camera. Therefore not all body movements of the surgeons were recorded. Our video was limited to only a single plane of view of the surgeon. A further limitation was that the open and laparoscopic procedures were not matched in terms of technical difficulty, and the study involved only the first hour of each operation. Lastly, our study group was small, which increased the chance of a type II error. Despite these limitations, however, the study demonstrated significant differences in musculoskeletal movements among surgeons performing laparoscopic and open operations. Further studies are needed to evaluate changes in the operating room environment that might minimize laparoscopic surgeons’ musculoskeletal discomfort.