In any practice that deals with injuries and accidents it is inevitable that there will be those few people who present with a permanent impairment of some nature. In order to provide an accurate assessment of one’s disability there is a standard of care by which a proper assessment and determination of impairment can be reached.

The Guides to the Evaluation of Permanent Impairment is the standard. Currently in its fourth edition the text is compiled by a list of contributors and editors of the American Medical Association. Started in the 50’s this guide provides objective measurements and computations for determining body impairments. The ratings are based upon measurable objective findings such as range of motion, strength, deformity, loss of sensation, and loss of organ function.

In thirty-eight states and two US territories the use of The Guides is mandated or recommended by law in worker’s compensation cases. In litigation cases the use of the guides is strongly recommended as an objective measurement of individual impairment.

Ratings are given stated as a percentage of loss for any affected body part or organ as well as a percentage of loss of function on the body as a whole.

The Guides defines an impairment as "an alteration of an individual’s health status ... assessed by medical means. An impairment is a deviation from normal in a body part or organ system and its functioning." The ratings apply to those impairments that are felt to be permanent. Permanency is defined as "adverse conditions that are stable and unlikely to change." The Guides address those impairments that are felt to be permanent and unlikely to change with any further surgery, time or therapy. This type of impairment will affect one’s ability to continue on with their normal activities of daily living.

In assessing an impairment there must be a thorough patient history including an explanation of the accident, an understanding of the patients home and work life. There must documentation stating how the patient can no longer perform his or her work duties and the affects on home life. While not everyone’ job may require heavy lifting, overhead work or throwing, patients who have impairments along these lines may not be able to enjoy their normal sports or family activities. This history must also include all treatment venues that have been tried and their success or failures also documented.

A comprehensive physical examination needs to be carried out even from the initial presentation of the patient. Depending on the system that is involved adequate range of motion, strength, functional capacity of organ systems and neuro/sensory losses must be documented. With therapy or surgery one must be able to documented any improvement or treatment failure. Once a physician feels that the patient has reached a maximal end point only then can a permanent impairment be adequately assessed.

Pain in and of itself is not something that can be measured objectively. In general the disability ratings for various organ systems make allowances for the pain that may accompany the disability. The exception to this is those patients with chronic pain. The Guides has a special chapter on the assessment of chronic pain. Even in these assessments it is noted that pain is subjective. The most accurate assessment will be based on one’s ability to carry out there activities of daily living in their work, home and social situations.. An individual who complains of constant pain but has no objective limitations in their activities of daily living has no impairment. If there are objective limitations of their activities it must be permanent and not likely to improve with any further intervention or surgery.

Patients need to realize that the Guidelines are quite specific and relatively strict. The complete loss of the thumb of the dominant hand is considered to be a 40% loss of function of the hand (Figure 3 ,Table 1, page 3/18) This calculates to a 36% impairment of the upper extremity ( Table 2, page 3/19.) This is then calculate to a 22% impairment of the whole body (Table 3, page 3/20.) A compression fracture of a lumbar vertebrae of greater than 50 percent of its height is rated as a 12% impairment of the whole body (Table 75, page 3/113.) A total hip or fracture prosthesis with fair results is calculated to be an impairment of 50% of the lower extremity and 20% of the whole person (Table 64, page 3/84.)