Neck ergonomics in rhinology surgeons: the impact of refractive surgical loupes

Introduction

Musculoskeletal strain is prevalent among surgeons and is a substantial contributor to discomfort, fatigue, and long-term injuries. Work-related musculoskeletal disorders (WMSDs) are common in the healthcare industry, with neck and back pain being the most cited disorders affecting workers from all disciplines. Within the surgical field, more than 90% of surgeons are affected by WMSDs (1-4). Rhinological surgeons are particularly affected by a forward-flexed head position that is often adopted during procedures. While cohort-specific data is lacking, surveys of Otolaryngologists’ report neck pain rates of over 80% at some point in their career, with other comparable surgical cohorts reporting rates of up to 90% (1). Given its high incidence and association with injury, time off work, and impact on the quality of life, it is imperative to consider musculoskeletal strain and how its impact can be reduced.

Optimisation of surgical ergonomics can minimise cervical neck flexion-related pain in surgeons. Surgical ergonomics refers to the interplay between the surgeon, equipment, workplace, and tasks (5). Changes in these factors must balance the risk of injury and improve efficiency. Examples include bed height, surgeon positioning (sitting vs standing), equipment positioning, and use of specialised equipment (microscopes and surgical loupes) (6).

Intraoperative positioning with pronounced cervical flexion for prolonged periods is common for Rhinological surgeons, who operate in small areas below eye level while standing. This forward head position can be objectively quantified by measuring the craniovertebral angle (CVA). Studies have shown that CVA measurements are a useful surrogate marker and predictive factor for neck pain (7-9), justifying the importance of ergonomic measurements.

Although some studies have used the CVA to intraoperatively evaluate ergonomic risk, objective observational data on interventions that aim to improve the CVA are sparse. Refractive surgical loupes are a strategy employed by rhinology surgeons to improve posture and reduce ergonomic strain. Unlike conventional loupes, which provide magnification only, refractive loupes alleviate the need for downward head inclination by incorporating angled prisms and redirecting the line of sight to the surgical field while permitting a more upright posture (thus increasing the CVA).

This study aimed to quantify the impact of refractive loupes on the CVA of operating surgeons. We hypothesised that the use of refractive loupes would increase the CVA. Quantifying this association is important for developing evidence-based ergonomic strategies, influencing surgical equipment design and choice, mitigating occupational risk, and improving surgeons’ well-being.

Methods

Study design

This prospective repeated measures observational study was conducted over 4 weeks in Queensland, Australia. Ten Rhinological Surgeons who met the inclusion criteria were recruited voluntarily and consented to participate. The sample size was chosen by the number of eligible surgeons available during the study period, and a convenience sample of ten surgeons was recruited. No formal power analysis was performed. The sample size was considered sufficient for comparison and identification of specific patterns that may warrant further investigation in larger studies. Surgeons who were Fellows of the Royal Australasian College of Surgeons (FRACS), able to provide informed consent, and operated on the anatomical structures of the nose were included in this study. Individuals with cervical spine pathology or recent musculoskeletal injuries were excluded (see Table 1 for the inclusion and exclusion criteria). The primary outcome was the association of refractive surgical loupes with the CVA of the operating surgeon. The study was completed and is reported according to the STROBE reporting guidelines (available at https://www.theajo.com/article/view/10.21037/ajo-2025-1-99/rc).

Data collection

The primary outcome measurement was the CVA, which was defined as the distance between the axial plane of the C7 spinous process and the intersecting line from the tragus (Figure 1). Adhesive reference markers were placed on these anatomical landmarks to facilitate the CVA measurements. Surgeons were fitted with refractive loupes and adjustments were made to ensure proper fit before use. No adjustments were made for any other surgical variables. The bed height, lighting, and positioning were set at the discretion of each surgeon. A physical reference device was placed directly behind the surgeon to facilitate the data analysis in the sagittal plane.

Figure 1 Superficial landmarks for craniovertebral angle measurement. This image is published with the participants’ consent.

Surgeons participating in the study were then observed operating under two conditions: standard loupes and refractive loupes. Video data was collected in the sagittal plane at a standardised distance of 1,400 mm. Height adjustments were made to ensure that the frame and reference points were equivalent to minimise parallax error. The surgeons were recorded for 5 minutes under each test condition. Data was analysed using open-source sports analysis software (Kinovea) to obtain the CVA every 0.1 seconds. These data points were analysed and those that contained any additional rotational or lateral head positioning were excluded from analysis because of inconsistencies in measuring the CVA.

Measurements were obtained during routine rhinology procedures, including open septorhinoplasty and closed septoplasty. These procedures require similar intraoperative positioning, and both conditions were assessed within the same case for each surgeon, ensuring a standardised operative context.

Surgical loupes

The two types of surgical loupes used in this study were the surgeons’ own standard loupes and refractive (Pentax Prismvue) Loupes. The standard surgical loupes used were the personal devices routinely used by the participating surgeons in their usual operative practice. As such, the standard surgical loupes were not standardised between surgeons and varied according to personal preference and manufacturer specifications (magnification from ×2.5 to ×3.0). The refractive loupes used had a magnification of ×3.0 and a field of view of 141 mm (10).

Variables

The primary outcome variable for this study was the association of refractive surgical loupes with CVA during standard rhinology procedures. The independent variable was the type of surgical loupe used. Each surgeon served as their own control to minimise confounding factors. The data collection for each participant was completed within the same operative case to further minimise confounding factors. Data collection and analysis were standardised between participants, and each was completed by a single researcher to ensure consistency.

Statistical analysis

For each surgeon, the CVA measurements were analysed and the mean and standard deviation calculated across all available measurements for both standard and refractive surgical loupe conditions. Differences between conditions were assessed using a paired t-test. Assumptions of normality were assessed prior to analysis. Statistical analysis was performed using R software (R version 4.4.0). Statistical significance was set at P<0.05.

Ethical statement

The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by the West Moreton Hospital and Health Service (WMHHS) Human Research Ethics Committee (No. EC00184). Informed consent was taken from all individual participants.

Results

Ten surgeons performed routine operations with and without refractive surgical loupes. For each surgeon, their CVA measurements were averaged for each condition and compared using a paired t-test. The mean difference between groups was 21.4 degrees [95% confidence interval (CI): 14.1–28.7] and was statistically significant (t=6.61, P<0.001). The data are summarised in Table 2.

Discussion

This observational study demonstrated a substantial improvement in the CVA when refractive loupes were used. An analysis of available data across both conditions for 10 surgeons demonstrated a statistically significant mean increase in the craniovertebral neck angle by 21 degrees, conferring a meaningful reduction in the operating surgeons’ neck flexion. Given the correlation demonstrated between CVA during procedural tasks and neck pain (7), these results suggest that this intervention is a feasible ergonomic intervention for Rhinological surgeons affected by WMSDs.

The association of WMSDs with the quality of life, disability, productivity, and longevity of surgeons in the workplace has been well discussed in the literature. Despite the overwhelming evidence, ergonomic interventions are often undervalued and ignored. To date, studies have focused on the subjective evaluation of ergonomic risk and pain scores, with few investigating specific interventions applicable to operating surgeons. By making a direct comparison between standard and refractive loupes (see Figure 2), this study provides quantitative evidence supporting their use for postural modification during surgery.

Figure 2 Comparison of craniovertebral angle between standard (B) and refractive loupes (A). This image is published with the participant’s consent.

Despite the significance of these results, this study has some limitations that should be considered. The small sample size and specific inclusion criteria limit generalisability. Observational bias may have impacted the results, given the participants’ awareness of the observations, leading to subconscious changes in posture. The potential for measurement errors due to inaccurate data collection and other confounding surgical factors is a limitation that should be addressed in future studies. Finally, the study investigated only short-term postural changes without assessing longer-term musculoskeletal outcomes. Whether improvements in CVA translate into meaningful reductions in fatigue, occupational injury, or pain remains a subject for future research.

To ensure reliable measurement of the CVA within the sagittal plane, frames demonstrating axial rotation or lateral flexion were excluded from the final analysis. While this approach standardised CVA measurement by minimising distortion inherent in two-dimensional video analysis, it does not account for the influence of three-dimensional postural variables. Although assessment across multiple planes was beyond the scope of this study, future research incorporating three-dimensional analysis would provide a more comprehensive evaluation of surgeon posture.

An additional limitation to consider was the use of non-standardised standard surgical loupes during the control phase of testing. As participants used their own personal loupes, magnification and specifications varied between individuals, potentially confounding results. However, given the study aimed to quantify the impact of refractive loupes on the CVA of operating surgeons, with each acting as their own control, the impact of this was not considered to be meaningful.

Despite the limitations, the results of this study demonstrate that refractive surgical loupes represent a practical ergonomic intervention for rhinology surgeons. The improved posture achieved through this intervention may mitigate WMSDs in surgeons and improve their career longevity and quality of life (though further research investigating long-term outcomes is required).

Conclusions

This study demonstrated that the use of refractive surgical loupes significantly improved the CVA of Rhinological surgeons during surgical procedures. By reducing problematic neck flexion without compromising the surgeon’s visual field, the results of this study suggest that the use of refractive loupes is a practical and effective ergonomic intervention for reducing occupational risks. Whilst these findings provide objective ergonomic data that supports the use of refractive optics, further longitudinal research is required to determine whether the changes translate into measurable reductions in WMSDs.

Acknowledgments

The authors acknowledge the contribution from Dr Andrew Jones for statistical support received through Data Science Collaborative Research Platform, The University of Queensland, Australia.

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://www.theajo.com/article/view/10.21037/ajo-2025-1-99/rc

Data Sharing Statement: Available at https://www.theajo.com/article/view/10.21037/ajo-2025-1-99/dss

Peer Review File: Available at https://www.theajo.com/article/view/10.21037/ajo-2025-1-99/prf

Funding: None.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://www.theajo.com/article/view/10.21037/ajo-2025-1-99/coif). The refractive surgical loupes used in this study were loaned by Pentax for research purposes, with no involvement in the study design, data collection, analysis or manuscript preparation. The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by the West Moreton Hospital and Health Service (WMHHS) Human Research Ethics Committee (No. EC00184). Informed consent was taken from all individual participants.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Alem A, Abdalwassie L, Alharbi AA, et al. Neck Pain Among Otolaryngologists, Head and Neck Surgeons. Saudi Journal of Otorhinolaryngology Head and Neck Surgery 2018;20:56-61.
2. Epstein S, Sparer EH, Tran BN, et al. Prevalence of Work-Related Musculoskeletal Disorders Among Surgeons and Interventionalists: A Systematic Review and Meta-analysis. JAMA Surg 2018;153:e174947. [Crossref] [PubMed]
3. Bolduc-Bégin J, Prince F, Christopoulos A, et al. Work-related musculoskeletal symptoms amongst Otolaryngologists and Head and Neck surgeons in Canada. Eur Arch Otorhinolaryngol 2018;275:261-7. [Crossref] [PubMed]
4. Szeto GP, Ho P, Ting AC, et al. Work-related musculoskeletal symptoms in surgeons. J Occup Rehabil 2009;19:175-84. [Crossref] [PubMed]
5. Kutler RB, Rameau A. Female Surgical Ergonomics in Otolaryngology. Oper Tech Otolayngol Head Neck Surg 2025;36:132-8. [Crossref] [PubMed]
6. American College of Surgeons. Surgical Ergonomics Recommendations. 2023. Available online: https://www.facs.org/media/tdeemrnw/23_ed_surgicalergonomicsrecommendations_pdf_v4.pdf
7. Binaei F, Kahlaee AH, Taghizadeh Delkhoush C, et al. The correlation between pain and flexor and extensor muscles endurance and size with craniovertebral angle changes during prolong sitting task. J Bodyw Mov Ther 2025;45:400-5. [Crossref] [PubMed]
8. Rani B, Paul A, Chauhan A, et al. Is Neck Pain Related to Sagittal Head and Neck Posture?: A Systematic Review and Meta-analysis. Indian J Orthop 2023;57:371-403. [Crossref] [PubMed]
9. Kim DH, Kim CJ, Son SM. Neck Pain in Adults with Forward Head Posture: Effects of Craniovertebral Angle and Cervical Range of Motion. Osong Public Health Res Perspect 2018;9:309-13. [Crossref] [PubMed]
10. Pentax Loupes2025. Available online: https://www.pentaxloupes.com/#features