Preventing work-related musculoskeletal injuries among oral and maxillofacial surgeons

Abstract

BACKGROUND:

Oral and maxillofacial surgeons (OMS) are continually required to adjust position and posture to access the limited surgical field in and around the head and neck, oral cavity, and oropharynx. Very limited data exists that quantifies the burden of musculoskeletal disorders (MSD) among OMS.

OBJECTIVE:

This exploratory study seeks to address these literature gaps by assessing the prevalence of MSD among OMS.

METHOD:

A 12-question survey was designed to investigate the prevalence of MSD for OMS, including residents in training, actively practicing surgeons, and retired surgeons. Seventy-six surveys were distributed and completed in person by surgeons attending professional conferences from September 2018-September 2019. Survey questions included the Baker-Wong Faces pain scale, years in practice, number of hours worked per week, job tenure, pain attributable to work, and age. The Nordic scale identified and delineated anatomic site of musculoskeletal complaints, duration and treatment sought.

RESULTS:

The most frequently cited sources and locations of pain attributable to occupation were shoulders, neck, and lower back. The risk of MSD symptoms was relatively two-fold [PR = 2.54, 95% CI = 0.90, 7.22] among OMS in practice for more than ten years compared to those in practice less than ten years. After adjusting for age and hours worked per week as potential confounders, the risk of MSD symptoms was higher among OMS in practice for more than ten years compared to those with less than ten years of experience, despite no statistically significant association.

CONCLUSION:

OMS are impacted by a high prevalence of MSD. The neck, shoulder, and lower back are the most frequently affected with discomfort and pain. This study found that practicing oral and maxillofacial surgery for more than 10 years is a potential risk factor for experiencing MSD. Keywords: Occupational pain, surgical ergonomics, work-related injuries, oral surgery, occupational injury prevention, return to work, workplace health promotion.

Keywords

Oral surgery repetitive strain injury occupational injury surgical ergonomics

1 Introduction

Oral and maxillofacial surgeons (OMS) routinely adopt operative positions that are both mentally and physically demanding. OMS engage in operative positions that lead to sustained awkward body postures, repetitive motions, and forceful exertions, which are often driven by personal levels of comfort as opposed to ergonomically guided principles [1 –5]. These surgeons are expected to acquire and maintain enormous amounts of surgical techniques to facilitate favorable surgical outcomes for their patients. In addition to knowledge of surgical techniques, mastery of surgical skills is critical to ensuring patient safety, and the ability to translate knowledge into skills results in performance-based pressures. Personality traits of OMS (e.g., pride, grit, stamina, tough-mindedness) in certain operating scenarios may lead surgeons to ignore their physical discomfort for the sake of performing and completing surgical maneuvers [1 , 7]. The cumulative impact of both the physical and mental tasks often comes at the expense of the surgeon’s health and wellness resulting in a variety of musculoskeletal disorders (MSD) [8, 9].

The literature suggests that among health care professionals, dentists and surgeons have the highest prevalence of occupation-related MSD [10 –12]. All surgeons that operate in the head, neck, and oral cavity regions perform many repetitive tasks, assume static positions for sustained durations without breaks, and frequently endure discomfort during surgical procedures and thus are at increased risk for MSD [34]. Other medical-surgical specialties working primarily in the head and neck region, including otolaryngologists, plastic surgeons, and head and neck surgeons experience significant rates of MSD as well [8 , 35]. Limited data exists comparing OMS to general dentists and other dental specialties, however OMS may experience a higher prevalence of MSD [30].

Relating to site of MSD injury, a study among 43 surgeons in Gujarat identified the prevalence of work-related MSD symptoms as associated with ergonomic risk factors in which the back region, neck, and shoulders were the most frequently cited area of pain in the last 12 months [15]. According to Stone et al., oral health professionals considered MSDs a known risk in dentistry with limited capacity to reduce the risk of developing symptoms [33]. The tenacity required to perform complex surgical procedures within the oral cavity can result in acute or chronic pain such as tendonitis, synovitis, tenosynovitis, and bursitis [8 , 16–21]. This is because OMS routinely holds stressful body positions where over half of the body’s muscles remain contracted with minimal movement of the vertebral joints [21]. Another challenge that OMS may experience is the preference to stand while performing surgical procedures [22]. The combination of cumulative hours while standing and operating in the oral cavity often manifests into various symptoms of back, neck, hand, wrists, and shoulder ailments. These symptoms of pain and injuries can be further exacerbated by the use of aids to improve visibility, such as headlights, magnifying loupes, and microscopes [12 , 23]. These unfavorable results and experiences of pain align with the literature across a variety of surgical specialties. Research shows that activities that require a high cognitive load while holding static postures for long durations result in clinical practice modifications or restrictions, leave of absence, job burnout, and early retirement [9 , 24].

The knowledge of the prevalence and potential risk factors of MSD among OMS is limited. This study aims to address the literature gap by assessing the prevalence and potential risk factors of MSD among OMS. Findings from this study are paramount to identifying the magnitude of MSD and promoting ergonomic policies and education to improve current clinical practices. The literature indicates a severe deficiency in occupational health education and ergonomic training not only for OMS but also for surgeons in general and particularly for those practicing in the dental environment (e.g., dental specialists, general dentists, dental assistants, dental hygienists, dental therapists). It is hypothesized that the implementation of a standardized ergonomic and fitness curriculum can potentially reduce the incidence of occupational musculoskeletal-related injuries for OMS, other surgeons, and those practicing or working in dentistry. While it is indisputable that poor mental health is contributory to job burnout and disability, this study focuses on the physical consequences of the physical demands of the profession.

2 Materials and methods

2.1 Study design and sample

The authors designed and implemented a cross-sectional study. A convenience sampling of OMS in training, actively working, and retired were recruited at three different annual professional conferences between September 2018 to February 2020. Eligible participants were recruited onsite at each conference inviting them to complete a printed-paper survey. Inclusion into the study was based on current job position or experience as an OMS. All respondents were included in the study.

2.2 Data collection methods

The paper survey consisted of a 12-item questionnaire that ascertained characteristics of the study population (age, sex, years in practice, type of practice), self-reported current and past MSD symptoms, location of pain (neck, shoulders, upper back, elbows, wrist/hands, lower back, hips/thighs, knees, ankles/feet), and exposure history at work (hours worked per week and hours of direct patient care). The Nordic scale was adapted from the Nordic Musculoskeletal Questionnaire (NMQ) which was developed to collect epidemiological data and included in the survey [25]. Data were collected during three time periods from OMS and residents. The survey consisted of multiple-choice and fill-in-the-blank question prompts (Appendix).

2.3 Variables

The primary exposure of interest was job tenure. Job tenure was determined using a question prompt “How long have you been in practice?” quantified by a continuous interval (e.g., 0-5 years, 6-10 years, 11-15 years, 16-20 years,>20 years, retired). Age in years was categorized into nine different categories (e.g.,<30, 31-35, 36-40, 41-45, 46-50, 51-55, 56-60, 61-65,>65) and hours worked in a week was categorized into four groups (e.g.,<25, 26-35, 36-45,>45). The primary outcome of interest was career pain. Career pain was determined using a yes-or-no answer to the question prompt, “Have you had any physical pain/injury during your entire career that you attribute to your work?”.

2.4 Data analysis

All analyses were performed using Stata Software Version 15.1. Data collected from paper surveys were imported into Stata. Data analysis started with descriptive statistics using frequencies and percentages to summarize the characteristics of the study population and self-reported pain in areas of the body. For analysis, the following variables were dichotomized: age, hours of work per week, and job tenure. It was decided among the authors that dichotomizing the following variables was to emphasize a prevention approach among those entering this occupation. Discussions with OMS currently practicing in the field identified two distinct categories for analysis - early career surgeons versus seasoned surgeons. This approach was applied to the analysis to provide a future framework for preventing MSD commonly experienced among seasoned surgeons. Dichotomous variables (yes/no) were created by age, work experience (early career≤35 years old, seasoned≥36 years old), hours worked in a week (≤35 hours per week,≥36 hours per week), and job tenure (practicing for≤10 years, or early career surgeons and practicing≥10 years or seasoned surgeons). Log binomial regression was used to estimate the prevalence risk of MSD symptoms among oral surgeons and their job tenure. Prevalence ratios were used to interpret study findings.

2.5 Ethical approval

The current study was submitted to be reviewed by [Institution is masked for review] and determined as exempt from human subject research and informed consent by Institutional Review Board (IRB) due to de-identified data.

3 Results

Seventy-six participants responded to the paper survey (Table 1). Out of all the study’s participants, thirty-five identified as male (46%), and eight identified as female (11%). A total of thirty-three participants (43%) did not disclose their sex. Job tenure of the study group was as follows; 46% reported practicing less than 10 years and 55% reported practicing more than 10 years. 22 participants (29%) reported 35 years old or less and 54 participants (71%) reported 36 years old or older. A total of 47.4% of OMS who participated in our survey reported currently experiencing musculoskeletal pain.

Table 1
Personal characteristics of study participants (n = 76)

Characteristics of oral surgeons n %

Age

<30 11 15

31-35 11 15

36-40 7 9

41-45 10 13

46-50 6 8

51-55 9 12

56-60 2 3

61-65 9 12

>65 10 13

Missing 1 1

Sex

Male 35 46

Female 8 11

Missing 33 43

Job tenure

0-5 years 29 38

6-10 years 6 8

11-15 years 6 8

16-20 years 8 11

>20 years 22 29

Retired 5 7

Hours worked (per week)

<25 hours 2 3

26-35 hours 7 10

36-45 hours 22 30

>45 hours 42 58

Characteristics of oral surgeons	n	%
Age
<30	11	15
31-35	11	15
36-40	7	9
41-45	10	13
46-50	6	8
51-55	9	12
56-60	2	3
61-65	9	12
>65	10	13
Missing	1	1
Sex
Male	35	46
Female	8	11
Missing	33	43
Job tenure
0-5 years	29	38
6-10 years	6	8
11-15 years	6	8
16-20 years	8	11
>20 years	22	29
Retired	5	7
Hours worked (per week)
<25 hours	2	3
26-35 hours	7	10
36-45 hours	22	30
>45 hours	42	58

Study findings from Table 2 found that among early career surgeons, shoulders (42.9%), neck (31.4%), and lower back (28.6%) were the top three reported body areas affected by work tasks in the last 12 months. This trend was also seen among seasoned surgeons where the highest reported areas affected by work tasks were shoulders (38.7%), neck (37.3%), and lower back (31.5%). In addition to the highest prevalence of affected body areas, notable differences were also found between early career and seasoned surgeons. Early career surgeons reported specific body areas affected of elbows (2.9% vs 12.5%), knees (8.6% vs. 20.0%), and wrist/hands (11.4% vs. 32.5%) compared to seasoned surgeons.

Table 2

Prevalence of MSD among OMS in the last 12 months

	Early career surgeon		Seasoned surgeon		Total population
Location	Prevalence	Total N	Prevalence	Total N	Prevalence	Total N
Shoulder	42.9%	35	35.0%	40	38.7%	75
Neck	31.4%	35	42.5%	40	37.3%	75
Lower back	28.6%	35	34.2%	38	31.5%	73
Wrists/Hands	11.4%	35	32.5%	40	22.7%	75
Upper Back	20.0%	35	12.8%	39	16.2%	74
Knees	8.6%	35	20.0%	40	14.7%	75
Hips/Thighs	14.7%	34	12.5%	40	13.5%	74
Ankles/Feet	11.4%	35	10.0%	40	10.7%	75
Elbows	2.9%	35	12.5%	40	8.0%	75

Note: The prevalence = the proportion of OMS that self-reported yes to experiencing MSD in the selected locations

Table 3 presents the log-binomial model assessing the crude association between the risk prevalence of MSD symptoms among OMS’s job tenure. This study found a statistically significant association among oral maxillofacial surgeons with more than 10 years on the job and increased risk of MSD symptoms when compared to those with less than 10 years on the job (PR = 1.96, CI = 1.09-3.54). Additionally, Table 3 presents an adjusted log-binomial model assessing the increased risk of MSD symptoms and job tenure among OMS, after adjusting for age and hours worked per week. This model illustrates no statistically significant association between the risk of MSD symptoms among OMS’s tenure, after controlling for age and hours worked per week (PR = 1.96, CI = 0.897-7.22).

Table 3

Assessing the association between career pain and job tenure among OMS

	Crude				Adjusted
	n	PR	95% CI	n	PR	95% CI
Job tenure	76	1.96*	1.09	3.54	76	2.54	0.90	7.22

Note: Adjusted for age and hours worked per week; *=statistically significant 0.05≤p.

4 Discussion

The data from this survey shows among OMS surveyed, there is a significant prevalence of MSD that can be attributed to the physical work on the job with 47.5% of participants reporting experiencing current pain. Rambabu and Suneetha used the Nordic scale and found that dentists (67%) have a higher prevalence of MSDs than physicians (20%) and surgeons (37%) [11]. In like manner, the most self-reported location of MSD prevalence in our study population was the shoulder (38.7%), neck (37.3%), and lower back (31.5%). In contrast, Rambabu and Suneetha’s highest prevalences were shoulder (18%), neck (30%), and lower back (24%) [11]. In this current study of OMS, the upper regions of the body (specifically the neck and shoulders) showed a higher prevalence of pain than the lower back. This study found that elbows, knees, and wrists/hands have major differences between early career and seasoned surgeons, which is similar to findings of career tenure by Alnaser et al [26]. Future research could be done in this area, particularly on interventions to prevent adverse outcomes. It is possible that the finesse nature of oral and maxillofacial surgery and spending long durations in postural malposition will influence MSD in these regions of the body. It puts forth the hypothesis that standing may be protective of lower back injury, which may be a fertile avenue for future research. The data shows that early career and more seasoned OMS have comparable risk of MSD. Detailed studies among dentists of different specialties is needed for an in depth understanding of differences between general dentistry and all of the dental specialties.

This study also supports that there is a lack of awareness and potential knowledge deficiency in proper ergonomics and fitness strategies to help prolong the OMS’s career. Other physically demanding occupations such as firefighting, auto factory workers, and military personnel have well-established protocols in place to protect and enhance the health of the workers. Protocols for professionals such as OMS, surgeons, dentists, and others working in the dental field are extremely limited. If this knowledge is not gained during professional development or additional training, it can result in painful and debilitating MSD in OMS. The data collected shows the most affected sites of MSD are the shoulder, neck, and back. An interesting study conducted by Yiu et al. found that work posture and neck muscle strength in dental students could be improved with a 10-week exercise intervention [29]. The authors are of the opinion that a combination of stretching and strengthening of the pectoralis major, serratus anterior, latissimus dorsi, posterior deltoid, rhomboids, levator scapulae, and trapezius muscles will lead to less pain in the neck, upper back, and shoulder [27, 28] and have a keen interest in developing such protocols.

4.1 Limitations

This study has several limitations. A strong bias is that this study relies on self-reported questionnaire data. There is also survivorship bias, with only data collected from those OMS who were in good enough physical shape to give their information. Data was collected at a professional gathering which introduces a different kind of selection bias, both volunteer bias for those willing to participate in the research process and a corresponding underrepresentation of professionals who were not at the conference. This research project uses cross-sectional data collection, which may lead to temporal bias and a lack of causal inferences. While there is precedent in the ergonomic literature for larger surveys to be composed of smaller instruments and additional items (particularly for cross-sectional studies), it would have been prudent to formally validate and pilot test the data collection tool prior [31]. The sex of participants was not assessed in the adjusted model due to missing responses. The sample size was also small and thus limits generalizability.

5 Conclusion

This study has identified the prevalence of MSD in the OMS. A significant knowledge gap in proper ergonomics and fitness strategies to sustain OMS in training and practice has been identified. Implementing an ergonomic and fitness program in OMS practice can potentially reduce the risk of experiencing MSD. OMS should consider monitoring precursors to MSD by identifying discomfort and pain before conditions worsen. We recommend screening OMS and interns using the Nordic scale periodically to identify areas of discomfort and provide educational sessions and exercises accordingly. Thus, it is imperative to implement a curriculum combining ergonomic training and targeted fitness regimens during residency training that would prepare surgeons for the rigors of OMS training and beyond. Periodic screening using the Nordic scale could identify precursors to MSD before conditions worsen. Employing a combination of ergonomic education, specific fitness strategies and periodic MSD screening will combat MSD commonly seen in OMS and would improve longevity and career satisfaction. This study provides baseline data and the potential to expand future research assessing prevention strategies for MSD among OMS. Future research should assess the differences between male and female OMS and interns while considering anthropometric measurements and methods of exercise. As noted earlier, the research could also examine if standing may be protective against lower back injury.

Ethical approval

The study was approved by the University of Minnesota Twin Cities Institutional Review Board (STUDY00011351).

Informed consent

The current study was submitted to be reviewed by University of Minnesota Twin Cities and determined as exempt from human subject research and informed consent by the Institutional Review Board (STUDY00011351) due to de-identified data.

Conflict of interest

The authors declare that they have no conflicts of interest.

Footnotes

Acknowledgments

The authors have no acknowledgments.

Funding

The authors report no funding.

Supplementary materials

The appendix is available from .

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