Abstract and Introduction
Objective: The aim of this study was to review musculoskeletal disorder (MSD) prevalence among surgeons performing minimally invasive surgery.
Background: Advancements in laparoscopic surgery have primarily focused on enhancing patient benefits. However, compared with open surgery, laparoscopic surgery imposes greater ergonomic constraints on surgeons. Recent reports indicate a 73% to 88% prevalence of physical complaints among laparoscopic surgeons, which is greater than in the general working population, supporting the need to address the surgeons’ physical health.
Methods: To summarize the prevalence of MSDs among surgeons performing laparoscopic surgery, we performed a systematic review of studies addressing physical ergonomics as a determinant, and reporting MSD prevalence. On April 15 2016, we searched Pubmed, EMBASE, the Cochrane Library, Web of Science, CINAHL, and PsychINFO. Meta-analyses were performed using the Hartung-Knapp-Sidik-Jonkman method.
Results: We identified 35 articles, including 7112 respondents. The weighted average prevalence of complaints was 74% [95% confidence interval (95% CI) 65–83]. We found high inconsistency across study results (I2 = 98.3%) and the overall response rate was low. If all nonresponders were without complaints, the prevalence would be 22% (95% CI 16–30).
Conclusions: From the available literature, we found a 74% prevalence of physical complaints among laparoscopic surgeons. However, the low response rates and the high inconsistency across studies leave some uncertainty, suggesting an actual prevalence of between 22% and 74%. Fatigue and MSDs impact psychomotor performance; therefore, these results warrant further investigation. Continuous changes are enacted to increase patient safety and surgical care quality, and should also include efforts to improve surgeons’ well-being.
After participating in this activity, the reader should be better able to:
- Recall both the significance of ergonomics in minimally invasive surgery and the symptoms associated with musculoskeletal disorders.
- Critically appraise the ergonomics of one’s own surgical work environment.
- Anticipate or intervene in the occasion of experiencing physical fatigue or musculoskeletal disorders.
The laparoscopic approach has become standard for many surgical interventions due to its benefits compared with open surgery, which include less postoperative pain, faster recovery, shorter hospital stay, and improved cosmetic results.[1–3] Widespread implementation of laparoscopic procedures has led to increased studies of ergonomics in surgery. The field of ergonomics deals with the design and evaluation of job tasks, products, and environments to improve their compatibility with people’s needs, abilities, and limitations. In particular, physical ergonomics focuses on human anatomical, anthropometric, physiological, and biomechanical characteristics as related to physical activity.
The field of minimally invasive surgery (MIS) is continuously evolving. Newer techniques, such as natural orifice transluminal endoscopic surgery (NOTES) and single-incision laparoscopic surgery (SILS), have greater benefits for the patient,[5,6] but may increase the physical workload for the surgeon.[7–9] On the contrary, robotic approaches have been introduced. Debates surrounding robotic surgery mainly focus on the costs and patient benefits. However, another important issue is that robotic approaches may provide ergonomic benefits to the surgeon—enabling the surgeon to operate from a seated posture, and allowing more degrees of freedom for instrument movement and 3D vision.[10,11]
Several ergonomic studies reveal that during laparoscopic surgery, surgeons face multiple constraints that directly expose them to risk factors for developing musculoskeletal disorders (MSDs).[12–14] These risk factors include static body posture, repetitive upper extremity movements, and force exertion from adverse positions. Moreover, the workload is increased by the high level of task precision and time pressure. Physical demands differ between open and laparoscopic surgery and comparative studies have reported higher prevalences of physical complaints for laparoscopic surgeons.[15–17] Recent studies report MSD prevalence rates of 73% to 88% among specialists in MIS.[18–20] Relative to the general population, these numbers are excessively high. The Fourth European Survey on Working Conditions presents the prevalences of several MSDs, reporting a 24.7% prevalence of backache, 22.8% prevalence of muscular pain, and 23% prevalence of neck and shoulder pain. A US-based study of a large occupational population reported a 20.8% prevalence of lower back pain. MSDs develop gradually and can affect different parts of the musculoskeletal system, including muscles, joints, and nerves. Laparoscopic surgeons mainly report issues involving their neck, back, shoulders, wrists, and thumbs. Symptoms associated with these MSDs predominantly include fatigue, pain, stiffness, and numbness. Such symptoms can affect task accuracy,[23,24] potentially having an indirect impact on patient safety, which is the main priority in surgery.
In our present systematic review, the primary objectives were to determine the overall prevalence of MSDs among surgeons performing minimally invasive abdominal surgery, and to determine whether MSD prevalence varies according to body region and minimally invasive surgical method. The secondary objectives were to identify how MSD prevalence among surgeons impacts surgical performance, and to identify additional risk factors beyond the general ergonomic risk factors. Our present findings will provide insight into the contemporary magnitude and characteristics of MSDs among surgeons, which will help to design interventions, increase awareness, and to develop recommendations for clinicians and medical technicians.
To summarize the overall MSD prevalence among surgeons performing MIS, we conducted a systematic review following the PRISMA guidelines. The search strategy was developed by CA, AdM, and TN in consultation with a research librarian at the Radboud University Library. On April 15 2016, we performed a search in PubMed, EMBASE, the Cochrane Library, Web of Science, CINAHL, and PsychINFO. The following search terms were used (as Medical Subject Headings and Title/Abstract words): “Human Engineering” OR “ergonomics” OR “human factors” OR “occupational health” OR “workload” AND “surgical procedures, minimally invasive” OR “minimally invasive surgery” OR “minimal access surgery” OR “laparoscopy” OR “endoscopy” OR “Surgery, Computer-Assisted” OR “Robotics.” Appendix 1, http://links.lww.com/SLA/B203 includes the full search strategies per database. We set no limits regarding year of publication, language, or publication status and we applied no other additional filters after running the search in the consulted databases.
Our present review focused on MIS performed in the abdominal cavity—including general, gynecological, and urological surgery. This limitation was applied because these specializations entail similar task-physical and environmental characteristics and, therefore, carry similar risk factors for developing physical complaints. For inclusion, studies had to address physical ergonomics as a determinant, report the prevalence of MSDs (or physical complaints) as a study outcome, and be published as full-text articles in a peer-reviewed journal.
All studies identified in the initial database search were independently reviewed by 2 researchers (CA and AdM). First, the titles and abstracts were screened to identify all articles related to physical ergonomics in MIS. Next, the full-text articles were obtained to determine eligibility for final inclusion in the synthesis. Disagreements were discussed with a third researcher (TN), and resolved by consensus. Finally, the references of the included articles were checked for additional articles of interest.
We recorded the following data from the included studies: year of publication, population/sample size/response rate, type of surgery, applied questionnaire, and primary and other relevant outcome measures. The primary summary measure was the reported prevalence of physical complaints. Secondary summary measures included predictors for symptom development and impact on surgical performance.
To evaluate the conduct of the included studies, we used the 22-item Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist.[26,27] Each reviewed article was assessed for all 22 items with 1 point given for each successfully addressed item, and a total score calculated as the sum of all items. Finally, we calculated the average score for all reviewed articles.
Finally, we performed random effects meta-analyses for both overall prevalence of physical complaints and body part specific prevalence. We calculated exact binomial confidence intervals (CIs) for the individual studies, and performed an arcsine transformation of the proportions for the meta-analyses. We expected to find high heterogeneity due to differences in the utilized questionnaires (validated or not validated), in the MSD definitions, and in the study time frames. Therefore, we pooled the individual prevalence rates using the Hartung-Knapp-Sidik-Jonkman (HKSJ) method for random effects. Heterogeneity was measured based on I2 and prediction intervals. Analyses were conducted in R (version 3.0.1; R Core Team 2012), using the meta package.
The database search identified 7844 articles, of which 345 were primary research articles addressing physical ergonomics in MIS. Cross-reference checking identified 4 additional articles. Evaluation of full-text manuscripts led to the final inclusion of 35 studies. Figure 1 shows the PRISMA flow chart with detailed information regarding the selection process.
PRISMA flow diagram.
Study appraisal yielded an average STROBE score of 17.5 (range 11 to 20) out of 22. Efforts to address potential sources of bias were poorly explained in the method sections, with only 2 articles successfully fulfilling this item. In addition, 7 articles failed to report the sample size, and 13 articles did not address the study limitations.
All included articles described survey studies, mainly using self-composed questionnaires. Four surveys reported integration of the Standardized Nordic Questionnaire for Musculoskeletal Symptoms (NMQ) or a modified version.[31–34] Five surveys[25,35–38] integrated the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) ergonomic questionnaire, as developed by the SAGES Ergonomic Task Force. To some extent, all studies subdivided the involved body regions, or enabled the respondents to describe the affected body parts. The articles widely differed in the terminology used for MSDs (eg, musculoskeletal symptoms, discomfort, injuries, or problems) and in the descriptors used to characterize the nature of the MSDs (eg, pain, numbness, stiffness, and fatigue). Moreover, the time period for occurrence of complaints ranged from a point prevalence (during or immediately after surgery), to a 12-month prevalence, to having ever experienced symptoms. The marked duration or emergence of musculoskeletal symptoms also varied from intraoperatively; shortly after surgery; up to recurrent, persistent, or chronic.
Response rates ranged from 6.1% to 100%, with an average of 40.2%. Overall, the reviewed studies included 7112 respondents who were mainly laparoscopic surgeons who performed procedures in general surgery, gynecology, and urology in both adult and pediatric patients. Three studies also included a subset of respondents (N = 378) that were (scrub) nurses, general physicians, anesthesiologists, or orthopedists.[13,40,41] Where possible, data from those respondents were excluded from our meta-analyses.
Table 1 provides an overview of included studies with itemized primary and other relevant outcomes. Of the included articles, 26 reported an overall MSD prevalence among surgeons performing any type of minimally invasive abdominal surgery, which ranged from 20% to 100% with an average of 74%, and a 95% CI of 65 to 83 (Figure 2).[13,14,16–20,25,32–34,37,38,41–53] We found high inconsistency across the study results, with an I2 value of 98.3%. Assuming that all nonresponders had never experienced physical complaints, the overall percentage would be 22% (95% CI 16–30). Among the laparoscopic surgeons with MSDs, the rate of chronic pain ranged from 10.8% to 51.5% with an average of 27% (95% CI 7–54).[16,18,19,32,53] The remaining 9 reviewed studies did not report an overall MSD prevalence, but rather reported MSD prevalence rates for specific body parts.[31,35,36,40,54–58] The body parts most commonly affected with discomfort or pain were the neck with 53% (95% CI 42–63),[14,16–18,20,25,31–34,36,40,41,43,47,49,51,53,54,56,57] back with 51% (95% CI 34–68),[14,17,18,25,36,43–45,47,49,53,54,56,58] shoulders with 51% (95% CI 41–60),[14,17,18,20,31,32,34,36,43,44,47,49,51,53,55–57] and hands with 33% (95% CI 14–55).[18,36,43,51,53,56] The inconsistency of the above-reported prevalence rates across studies was similar to that of the overall MSD prevalence.
Overall MSD prevalence.
Seven studies, including 1852 respondents, reported the prevalence of physical complaints related to robotic surgery.[16,17,32,33,46,48,54] These studies reported a 56% (95% CI 32–78) overall prevalence of complaints associated with robotic surgery.[16,17,32,33,48] Considering the defined time-frames in these studies, 52.8% of respondents reported ever experiencing physical discomfort,[32,33,48] and 50.4% of surgeons reported complaints or discomfort during robotic surgery.[16,17,33] Franasiak et al and Plerhoples et al, respectively, reported 11.9% and 5% rates of chronic or persistent strain due to robotic surgery. Robotic surgery was most commonly related to discomfort in the neck and in the hand/wrist region, including thumbs and fingers. On the basis of ergonomic considerations, respondents preferred the robotic operative modality compared with either open or laparoscopic surgery,[32,54] and expressed that robotic surgery can be helpful for improving ergonomics.[18,55] Accordingly, Plerhoples et al reported that among MSD sufferers, 8.3% attribute their physical complaints to robotic surgery, 36.3% to open surgery, and 55.4% to conventional laparoscopic surgery. Moreover, the difference in MSD prevalence is reportedly dependent on the body region.[16,17,34,55] Another 3 studies specifically determined the overall percentages of physical complaints during or after open surgery, reporting rates of 56.5%, 65%, and 85.4%.[16,17,55] Among the 5 reviewed studies that reported prevalence numbers for both open and laparoscopic surgery, all showed a higher prevalence of complaints in laparoscopic surgery than open surgery.[16,17,54–56]
Four studies reported that a substantial number of respondents (range 16.6% to 34.8%) believed that their physical complaints affected their surgical performance or activity.[31,41,44,55] Between 6.7% and 17% decreased their surgical practice (caseload) due to their physical complaints.[18,31,34] Park et al reported that 40% of respondents ignored their physical complaints during surgery. Szeto et al found that 35.6% of respondents always worked through pain so that the quality of their surgical work would not suffer. Bagrodia and Raman and Plerhoples et al, respectively, reported that 25% and 30% of surgeons gave some consideration to their own physical discomfort when choosing an operative approach.
The reviewed studies reported several risk factors for MSD development. Sutton et al specifically addressed sex as a risk factor, showing that female surgeons were significantly more likely to receive treatment for their hands and reported significantly more cases of shoulder discomfort, even with correction for glove size. Four other studies reported sex as a risk factor, showing that women were more likely to develop MSDs.[18,31,48,51] Berguer and Hreljac specifically addressed the relationship between hand size and difficulty using instruments, finding that surgeons with a small glove size reported greater difficulty using all laparoscopic instruments than surgeons with a medium or large glove size (P < 0.001). Franasiak et al found that increased pain symptoms were significantly associated with glove size; however, the majority of respondents in this study stated that their instruments fit “just right” (70.8% to 84.8%, depending on type of instrument).
Overall, 12 studies examined the constraints of laparoscopic instruments.[13,18–20,36,40,42,43,45,47,50,52] Three of these studies directly assessed the surgeons’ perspectives regarding handle design. Handle design was reported as a cause of physical complaints by 49% of respondents in the study of Sari et al, 74.4% in Park et al, and 83% in Matern and Koneczny. More specifically, Matern and Koneczny reported that 36% of surgeons complained about pressure areas, 26% about neuropraxia, and 57% about uncomfortable posture due to instruments. Cass et al found that difficulty manipulating instruments was a significant causative factor in injury of disc prolapse. Moreover, improper positioning of the surgical setup—including monitor height and position, table height, and use of foot pedals—affected the surgeons’ comfort and was indicated as a risk factor for MSD development in 8 studies.[13,14,19,20,36,40,47,52]
Eight studies assessed the workload in terms of caseload or number of hours spent performing MIS. The findings on this topic were somewhat ambiguous. Six studies reported that increased laparoscopic workload was significantly related to physical complaints.[19,42,43,46,51,53] In contrast, McDonald et al and Franasiak et al identified no relationship between caseload and physical complaints for conventional laparoscopic procedures. However, the latter study reported that the number of cases per day and case length were significant risk factors for MSD development in robotic surgery. Plerhoples et al found that surgeons with more laparoscopic cases (P < 0.0001), greater annual laparoscopic volume (P < 0.0001), or with longer career durations (P = 0.03) were more likely to attribute their pain to the laparoscopic modality.
Ten studies reported data regarding experience and age. Four studies found that less experienced surgeons were more likely to report physical complaints.[18,20,36,56] Accordingly, 4 studies reported that younger age was associated with higher rates of physical complaints.[18,20,53,56] In contrast, Stomberg et al and Cass et al reported that injury risk increases with age. Plerhoples et al identified no relationship between age or experience and physical complaints. McDonald et al reported that younger surgeons were more likely to report symptoms; however, this association disappeared with correction for sex. Park et al found that age and years of practice were not correlated with physical complaints. However, they identified a significant correlation between case volume and symptoms in the neck, right hand, upper extremities, and lower extremities (all P < 0.05). They concluded that the number of cases performed per year was a stronger predictor of physical complaints than either age or years in practice.
Our present systematic review was designed to evaluate the available literature regarding physical complaints and MSDs among surgeons performing laparoscopy. We found high inconsistency across studies, along with a low overall response rate. MSD prevalence among surgeons was found to be 74% (95% CI 65–83). However, if all nonresponders were assumed to have never experienced MSDs, this prevalence was adjusted to 22% (95% CI 16–30).
Despite early reports of the physical drawbacks of laparoscopic surgery in the late 1990s,[39,56] little has improved regarding the ergonomics and physical workload for surgeons. This may be partly because the laparoscopic approach has become the preferred approach from the patients’ perspective.[59–61] Furthermore, there has been clear development of greater surgical specialization. Consequently, subgroups of surgeons may spend a relatively high percentage of their daily activities performing laparoscopic procedures. Another issue is that a higher surgical caseload might actually be beneficial for several patient-reported outcome measures.[62–64] Altogether, these trends in the field have led to an overall rising caseload of laparoscopic procedures, with a correspondingly higher chance of surgeons developing MSDs.[16,18,32,34,43,48,51]
One might consider physical complaints to be a “part of the job.” However, when such complaints appear to negatively influence the quality of surgical care, it becomes a matter of professional ethics. Several reviewed studies described surgeons who believed that their surgical performance was negatively affected by their own injury or pain.[31,41,44,55] In 2 studies, respondents expressed that their physical complaints influenced their choice of operative approach.[16,54] This suggests that in some cases, patients may not receive the best clinical care available due to their surgeon’s physical condition. Szeto et al found that 35.6% of respondents reported almost always “working through pain so that the quality of their work would not suffer.” However, it remains unclear whether physical complaints really impact surgical outcomes. Especially in cases of laparoscopic hysterectomy or (hemi)colectomy—where important steps are taken late in the procedure—the physiological process underlying fatigue of the surgeon’s upper extremity may play a role in complaint occurrence. Sari et al found that no respondents reported any surgical complications due to their own fatigue or physical complaints; however, this could have been influenced by surgeons’ reluctance to admit to such occurrences.
There remains a need for further clarification of the difference in physical complaints between the sexes. On average, female surgeons have smaller hands and glove size. Almost all laparoscopic instruments have a “one size fits all” handle, and previous studies report that such handles are less comfortable for surgeons with small glove sizes.[18,42,52] This could partially explain the higher rates of physical complaints in the upper extremity among women. This finding could also be influenced by anatomical muscular differences between the sexes. Moreover, differences in interplay between working life and private circumstances may be of influence. Furthermore, it is possible that male surgeons are less aware of their complaints or more reluctant to admit that they experience physical complaints. The fact that less-experienced surgeons report more complaints justifies an enhanced focus on ergonomics during surgical residency. Junior surgeons are less familiar with laparoscopic procedures and may intrinsically experience higher mental and physical stress levels. Consequently, their main intraoperative focus will be on the surgical procedure, with less attention paid to their own physical status, surgical setup, or other ergonomic conditions. Implementing an ergonomic module for surgical residents will likely enhance their awareness of surgical conditions as a whole.
One reported benefit of the implementation of robotic surgery is that it offers superior ergonomics. However, our present review showed that sitting in the console still has its limitations, which is supported by evidence in several prior studies.[66,67] Among robotic surgeons, MSD prevalence is the highest in the neck, with up to 35% of robotic surgeons experiencing pain, stiffness, or numbness in this area.[16,17,32,33,46,54] Studies in pathologists and cytotechnologists demonstrate that prolonged use of conventional microscopes is a risk factor for developing (chronic) musculoskeletal injuries, including shoulder, neck, back pain, and fatigue.[68,69] Robotic surgery involves a similar body posture as working with a microscope. Thus, robotic surgeons may benefit from existing knowledge regarding ergonomic guidelines for prolonged microscope use.
This review has several potential limitations. First, the studies used different questionnaires and definitions of MSDs. The common use of terms, such as physical complaints, fatigue, numbness, and pain, contributed to overall inconsistency among studies. The appropriateness of pooling results obtained from various more-or-less self-composed questionnaires is scientifically debatable. However, this was regarded as the least objectionable option available for use in our present review. Furthermore, the STROBE score is not a formal tool for measuring methodological study quality, but was used in our study as a checklist for reporting several outcomes and biases. Another limitation is the possibility of recall bias. All reviewed studies were retrospective analyses, and it is possible that not all respondents were able to clearly report their physical condition. There is also a potential for selection bias, in that the respondents who had experienced physical complaints may have been more eager to complete a questionnaire on this topic. Consequently, the percentage of surgeons reporting physical complaints may be an overrepresentation within the whole population of laparoscopic surgeons. It is known that survey studies among physicians are prone to low response rates. However, it is possible that those surgeons who did not experience physical complaints were reluctant to respond to the questionnaires. Therefore, we recalculated the overall prevalence rate in case the nonresponders had never experienced physical complaints. Moreover, not all studies reported whether the surgeons were asked for their opinion on whether their physical complaints were more or less directly related to MIS. Future prospective studies must focus on the distinction between any MSD versus clinically relevant MSDs with regard to patient safety.
In conclusion, the findings of this systematic review indicate that the MSD prevalence among surgeons performing MIS is likely higher than is commonly acknowledged, warranting future well-designed studies. This matter is clinically relevant, as kinesiology studies reveal that fatigue and MSDs can impact psychomotor performance. Alongside epidemiological research, future studies should also focus on evaluating surgical tasks, environment, and instrument design[40,42,52,71] Interventions, such as formal ergonomic training,[19,25,32] warm-up before surgery,[72,73] and microbreaks during surgery,[74,75] may improve surgeons’ physical health and warrant further scientific evaluation.
We’d like to thank Dr Ir. J. IntHout for her contributions to our meta-analyses by applying her expertise regarding the HKSJ method.
Annals of Surgery. 2017;266(6):905-920. © 2017 Lippincott Williams & Wilkins