Technical Report AMI-MU-001:

Powered Examination Tables

Authors: Laura Johnson, M.S., Jack Winters, Ph.D., Melissa Lemke, M.S., Erin Promersberger, B.S.

Coordinating Editor: Jack Winters, Ph.D.

Location: Medical Device Accessibility & Usability Laboratory, Marquette University

Current Version & Key Contributor: 1.0 (August 2005, Promersberger)

Past Versions & Key Contributors: 0.5 (June 2005, Lemke), 0.4 (September 2004, Lemke), 0.3 (July 2003, Johnson), 0.2 (January 2003, Winters), 0.1 (January 2003, Johnson)

Table of Contents

Executive Summary

Making healthcare technologies accessible to persons with disabilities is an important area in medical research. Physical barriers often limit the medical care that can be provided to those with special needs. The first step in receiving medical care is a proper examination, which may be more difficult than it initially sounds. Many healthcare facilities are not equipped with examination tables suited for patients with disabilities, oftentimes because more accessible equipment is more expensive to purchase or medical purchasers are unaware of the needs of their patients and staff.

Patients with physical disabilities often have difficulty getting onto and off of the examination table, as well as with safe and comfortable positioning for an examination. Safety of both the patient and practitioner are dependant on the design of the table. In order to both preserve the patient’s independence and dignity and prevent back injury to medical staff, the table height must be low enough for patients to access it with little or no assistance and high enough to accommodate tall practitioners who are standing. Also, for women patients especially, a support system or stirrups with flexible degrees of freedom are necessary for proper positioning and support of the legs for a complete pelvic examination.

Most of the products reviewed for this report seem to have considered patients with disabilities in their designs. They demonstrate a wide variety of height and tilt adjustments so practitioners can easily adjust the table to positions appropriate for the necessary examination and for the comfort and safety of the patient. Several of the examination tables also include other safety and accessibility features, such as: restraints, handrails, and knee crutches. Some contain stirrups that lock into preset positions, while others provide a more flexible range that can be adjusted as needed for each patient. Some major limitations in designing products to be accessible to patients with disabilities are cost and limited enforcement of the Americans with Disabilities Act (ADA), which both affect the overall demand for these types of products. This technical report provides an overview of accessibility features currently available as well as suggestions for improvement.

Background

Examination table design has changed over the years according to the needs of society. With over fifty-one million Americans with a disability [1], as well as an aging society, the need for accessible examination tables has grown. Many healthcare facilities are not equipped with examination equipment that is easily accessible to patients and providers with disabilities. More complex tables may cost thousands of dollars more than the standard, but without these accessible tables people with disabilities may be unsafe, uncomfortable, or even unable to receive necessary medical attention.

Patient and staff safety is a primary concern when designing and purchasing examination tables. If a table is not low enough it may cause injury to the patient should (s)he try to move independently, or to the staff members if they assist with transfers. Once the patient is safely on the examination table, other safety features should be present to help the patient feel secure and comfortable, and each patient should be treated according to his or her desires for comfort and safety. Some patients may request the use of hand rails or support aides (e.g., pillows, wedges) for increased safety, while others may prefer the assistance of a nurse.

Purchasing an accessible examination table has also been presented as problematic for some healthcare providers. There is a tendency for purchases to be based solely on cost due to lack of reimbursement for the use of medical examination tables and limited enforcement of the ADA. Also, some of the accessible tables may not be suitable due to the limited space of an examination room. In general, practitioners prefer smaller examination tables, but then patients may not be as safe, storage space is limited and the tables may not include necessary accessibility features.

Product Table

For an overiew and instructions on how to navigate within the product table click here.

Product Survey

The Product Table provides a brief summary of powered examination tables currently available on the market, highlighting important accessibility design features. All tables presented have a powered height adjustment and a powered or spring-assisted backrest adjustment.

The first three columns denote the name, manufacturer, and suggested use. Each name and manufacturer contains a hyperlink to the respective website. The basic dimensions of the table are also included within the product table, emphasizing height adjustability. The maximum load limit is displayed as a key feature. Also illustrated are other available adjustments, including backrest and pelvic tilt, as well as the control method for making any adjustments.

Information within the accessories and safety features columns contain any additional options (either included or sold separately). Items found within the accessories column are general items such as stirrups, electrical outlets, and accessory rails. Safety accessories are additional products used to help increase patient safety, comfort, and security, such as restraints, hand rails and knee crutches.

The tables are also evaluated with respect to the following accessibility features:

Each was ranked on a scale of 1-3 in which 3 represents full accessibility to a person with the specific impairment and 1 represents inaccessibility to a person with the specific impairment. General accessibility is the average of all other accessibility scores.

Product Evaluation

While no formal product evaluation has been completed, it is clear that products presented in this survey include many desired accessibility features. It is known that for a device to be fully accessible to people who perform wheelchair transfers, the minimum height should be between 17" and 19". Brewer Company, Chattanooga Group, Hausmann, Keitzer, Midmark, Tarsus, and United Metal Fabricators all offer at least one table that reaches an accessible height. The Brewer Assist (Brewer Company) and 630 Universal Power Procedure (Midmark) tables both offer a range from 19"-40", which is ideal for independent patient transfers, as well as examinations by healthcare providers of taller stature. These examination tables are shown in Figures 1 and 2, respectively.

This picture shows the Brewer Assist Examination table at its low height of 19” with the backrest in the upright position. It is shown next to a wheelchair to illustrate ease of transfer.

Figure 1. Brewer Assist Examination Table [2]

This picture shows the Midmark 630 Power Procedures table at its low height with the backrest in the upright position and the footrest retracted. The controller is shown as well.

Figure 2. Midmark 630 Power Procedures Table [3]

Some of the tables included do not reach the 19" height that makes transferring accessible for wheelchair users, but other desirable accessibility features are noted. Other desirable accessibility features include easy adjustment (non-manual power), width that allows a patient to roll to the side or prone positions without feeling unsafe, and hand-holds to assist with transfers [4]. All of the tables presented use non-manual (or automatic) power. There is a trend toward wider tables (up to 40"), but it is also important to consider the limited space of the operating or examination rooms. The Brewer Access High-Low table offers safety grab bars to assist with patient transfer and position (see Figure 3), and many tables have safety rails or restraints.

This picture shows the Brewer Access High-Low table in two positions: as a chair, for patient transfer; and as a table, for the medical examination.

Figure 3. Brewer Access High-Low Table [2]

In general, powered tables are ideal for patients who are aging or have a disability. Most lower enough for easy transfer and come equipped with additional safety features such as restraints and side rails to increase the safety of an unstable patient. Few table designs have considered providers who are aging or have a disability, although providers with disabilities are increasingly users of medical devices due to our aging society.

Recommendations

While some examination tables have been developed to serve patients with disabilities, many hospitals do not have the budget or the motivation to purchase more accessible tables. Powered tables are significantly more expensive than manual or non-adjustable tables, and they are often thought of as an overhead cost because there is no reimbursement for their use. The first recommendation, based on this information, is to design a low-cost examination table that incorporates height adjustability and non-manual power.

Most manufacturers seem to consider accessibility features that benefit patients, but few consider providers who are aging or have a disability. One possible method to make tables more accessible to providers is to incorporate a non-constant velocity power assist system which utilizes the concepts of extended physiological proprioception (EPP) and mechanical impedence matching. EPP is the phenomenon that when a person is mechanically coupled to an object (such as a pencil or a tennis racket), his or her proprioception is extended through the object, and its location in space is known, even without a visual cue. If this control mechanism was implemented within an examination table, healthcare providers of all abilities could have greater control over the speed and position adjustment than with traditional manual- or power-adjustable examination tables. Regarding mechanical impedance matching, people typically adapt to their environment, exerting force based on what is required by the device they are operating. This adaptation is more difficult, and oftentimes impossible, for people with various disabilities. For this reason, it is necessary for the machine to adapt to the person. Related to examination table designs, sensors could be used to detect how much force the operator is capable of exerting, and then a motor could supply the remaining power required to adjust the position of the examination table. Future research and development work by the RERC-AMI is planned in this area, and more information will be added as more research is conducted.

Acknowledgment

This work is supported by the Rehabilitation Engineering Research Center on Accessible Medical Instrumentation, funded by the National Institute on Disability and Rehabilitation Research, U.S. Department of Education Grant #H133E020729. All opinions are those of the authors.

References

[1] "Americans with Disabilities: 2002." US Census Bureau. 20 July 2006 http://www.census.gov/hhes/www/disability/sipp/disab02/ds02t1.html

[2] Brewer. 3 Aug. 2006 http://www.brewercompany.com/

[3] Lemke, Melissa R. The Evaluation of Three Alternative Methods for Understanding Biomechanical Aspects of Medical Device Accessibility. Thesis. Marquette University, 2005.

[4] Midmark. 3 Aug. 2006 http://www.midmark.com/