Article

Ergonomics for the Glaucoma Physician

Prevent musculoskeletal disorders in day-to-day practice.

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The practice of ophthalmology for glaucoma is inherently physically demanding. In the clinic, repetitive work at the slit lamp or with the direct/indirect ophthalmoscope can generate muscle tension through the back, neck, and shoulders; in the operating room, great strain can be placed on the body as well. To ergonomic experts, these “non-neutral” positions that are repeatedly utilized can give rise to the development of musculoskeletal disorders (MSDs). Musculoskeletal disorders are a group of soft-tissue injuries resulting from long-term, repeated wear and tear on the body in the form of repetitive motion, force, vibration, and awkward positions. Muscles, tendons, ligaments, nerves, and joints all have the potential to be affected as small traumas accumulate over time.

Although MSDs are common occupational injuries across many professions, there has been increased awareness about MSDs in health professions and how to optimize the ergonomics of daily practice. The dental and laparoscopic surgery fields have numerous publications evaluating ergonomics and MSDs, and now the field of ophthalmology is starting to address the inherent risk within our work as well. A survey published in the American Journal of Ophthalmology in 2005 reported that 30% to 40% of the survey’s respondents had experienced symptoms of MSDs (mainly cervical spine and lower back problems, as well as carpal tunnel syndrome) within the preceding 30 days.1 These findings have been substantiated by additional reports on the high rate of MSD symptoms among ophthalmologists.2-5

The ramifications of MSDs can be significant. Beyond physical pain, they can have a financial impact due to temporary or permanent disability, productivity loss, or early retirement. In response to these studies, the American Academy of Ophthalmology (AAO) commissioned a task force to identify the ergonomic factors that can be modified in everyday practice to reduce the risk of MSDs and to educate members about safe practices from a musculoskeletal standpoint.

There are many aspects of both clinical and surgical practice that may predispose ophthalmologists in general and glaucoma specialists in particular to the development of MSDs. The National Institute of Occupational Safety and Health has identified categories that influence the development of MSDs.6 While not all work-related causes of MSDs can be modified, understanding how ergonomics play a role is important for the practicing ophthalmologist. Four activity-related factors encountered by a glaucoma specialist on a daily basis can increase the risk of MSDs:

  • Awkward postures: flexion/extension of the wrist, back, or neck, or positioning of the elbows away from the body;
  • Environmental factors: vibration, cold, and emotional stress, some of which a glaucoma surgeon might encounter;
  • High forces: the tight pincer grip of biomicroscopic lenses, gonioscopy lenses, or phacoemulsification handpieces can place substantial force on the carpal tunnel; and
  • Repetitive motions.

The impact of these factors in leading to musculoskeletal symptoms is most likely to be felt by physicians with high case loads. A survey of 697 ophthalmologists in the northeast United States found that age or duration of practice were not risk factors for reporting MSD symptoms. However, seeing more than 100 patients per week, performing ≥4 surgeries, and/or performing ≥6 laser surgeries per week were associated with increased risk of neck, upper extremity, or lower back pain.1 In addition, female ophthalmologists are at greater risk for developing MSDs than males, in part due to a shorter stature making it more likely that they will adopt awkward positions when treating patients.

Once a physician is aware of the ergonomic influences that can precipitate MSDs, small adjustments can be made in daily practice to help reduce the risk of developing musculoskeletal injuries. These ergonomic interventions do not necessitate a significant investment in physician time. In fact, a time-motion study of dentists found that proper patient positioning requires approximately 5 seconds.7 Taking the time to practice good technique can help to protect productivity in the long run. Below are some tips for how to make ergonomic adjustments in day-to-day practice.

Slit-Lamp Exam

Positioning of the physician and patient is essential for minimizing back, hip, and neck strain. To minimize stress on the lumbar spine and hips, the physician’s feet should be positioned flat on the floor with his or her back against the backrest of the chair (Figure 1). Raise the patient’s examination chair to allow the wheels of the doctor’s chair to slide under the footrest of the patient’s chair; this action will help to reduce the degree of forward flexion at the hips required by the physician during the slit-lamp exam. Keeping the neck in a neutral position is also critical; adjusting the oculars such that they are slightly below the neutral position of the physician can aid with this positioning. A soft elbow rest can reduce strain on the shoulder and elbow. It is also important to be mindful of wrist position: The wrist should be kept in a neutral position without extension or flexion. Always remember to move the exam chair to realign when examining the second eye. Do not torque your back to examine the left eye after the right eye exam is completed (Figure 1). Finally, reducing pincer pressure on the lens helps to lessen the forces that can contribute to MSDs.

Figure 1. For a slit-lamp exam, the physician’s feet should be positioned flat on the floor with his or her back against the backrest of the chair. Casters on a chair contacting the footrest underneath the patient (A) will cause the physician to lean forward. The patient chair should be elevated so that the casters can slide underneath and the physician can position properly (B). The physician should not place his or her elbow on a hard surface or bend sideways in the chair (C, D). It is better to use a soft cushion to decrease the contact stress on the elbow (E). Avoid using the hard lens case as an elbow rest (F). Additionally, it is preferable to move the chair instead of leaning the torso from side to side while using the slit lamp.

Indirect Ophthalmoscopy

Excessive neck flexion and awkward postures are commonly seen during indirect ophthalmoscopy. Properly positioning the indirect on the head, reclining the patient, and raising the chair will significantly decrease neck flexion. Supporting one’s hands on the patient’s forehead and face will reduce shoulder stress. Loosening the pincer grip on the lens will reduce carpal tunnel forces.

Exam Room Layout

Electronic medical records are becoming ubiquitous. Physicians must pay attention to how computer screens are oriented in relation to the patient chair. Setting up the exam room to reduce awkward neck postures, prevent torqueing the back, and avoid the sharp edges of desks can reduce the risk of MSD symptoms. Providing as much adjustability as possible in the room is helpful.

Operating Room

Ophthalmic and particularly glaucoma surgery has many potential intervention points in regard to ergonomics in the operating room. One of these is the block. Similar to the indirect examination, positioning the operating chair to reduce neck flexion and awkward postures is critically important. For the operating chair, using operative beds with electric controls rather than manual controls (like a foot pump and crank) will reduce the risk of injury for the physician and staff. A wrist rest can help to reduce stress on the shoulders and trapezius. However, resting the wrists on a hard metal object can increase the risk of mechanical injury. Padded wrist rests can diminish this possibility.

To position the scope, oculars should be positioned slightly below the neutral position of the surgeon. Scopes with extended oculars will allow the surgeon to utilize the backrest of a chair, thereby supporting the spine. Feet should be on the floor or on pedals at a similar height. If there is a mismatch of pedal height, add towels under the lower profile pedal to equalize height.

For cataract surgery, operating from a temporal location allows for improved positioning of the scope/surgeon. Angling the scope by 20° allows the surgeon to avoid a flexed and kyphotic neck and back (Figure 2). This position will also allow the surgeon to better utilize the back support of the chair. Holding instruments firmly is required but should be monitored, and if possible, force should be reduced. Taking frequent breaks to reduce pressure on the carpal tunnel is important.

Figure 2. Neutral spinal curvature and reduced musculoskeletal workload with the microscope tilted to accommodate a more neutral posture.

Other Causes and Conclusion

While there is significant risk of injury during ophthalmic-related activities, one must also consider the impact of texting (significant neck flexion), multitasking by cradling a cell phone with the neck, bending, lifting, and other daily activities. Aerobic and core exercises, maintaining a healthy weight, avoidance of smoking, and reduction of stress are critically important to a physician’s overall well-being. For a comprehensive review of the AAO Task Force recommendations, the authors recommend the ergonomics course available on the AAO One Network (https://www.aao.org/course/ergonomics-best-practices-course ). GP

References

  1. Dhimitri KC, McGwin G Jr, McNeal SF, et al. Symptoms of musculoskeletal disorders in ophthalmologists. Am J Ophthalmol. 2005;139(1):179-181.
  2. Kitzmann AS, Fethke NB, Baratz KH, Zimmerman MB, Hackbarth DJ, Gehrs KM. A survey study of musculoskeletal disorders among eye care physicians compared to family medicine physicians. Ophthalmology. 2012;119(2):213-220.
  3. Chatterjee A, Ryan WG, Rosen ES. Back pain in ophthalmologists. Eye (Lond). 1994;8(Pt 4):473-474.
  4. Sivak-Callcott JA, Diaz SR, Ducatman AM, Rosen CL, Nimbarte AD, Sedgeman JA. A survey study of occupational pain and injury in ophthalmic plastic surgeons. Ophthalmic Plast Reconstr Surg. 2010;27(1):28-32.
  5. Kaup S, Shivalli S, Kulkarni U, Arunachalam C. Ergonomic practices and musculoskeletal disorders among ophthalmologists in India: An online appraisal. Eur J Ophthalmol. 2018. [Epub ahead of print]
  6. US Department of Health and Human Services National Institute for Occupational Safety and Health. Proposed national strategies for the prevention of leading work-related diseases and injuries. Cincinnati, OH: Association of Schools of Public Health; 1986.
  7. Dougherty M. Ergonomic principles in the dental setting. June 2001. Thomson Healthcare/Dental Products Report. Available at: http://www.designbyfeel.com/wp-content/uploads/2010/09/papers_ergonomic_principles_part1.pdf