AMA Guides and Impairment Determinations: A Rater's Point of View

Thursday, March 4, 2010 | 2

By Luis Pérez-Cordero

Despite recent conflicting messages within the industry, the importance of using the AMA Guides in determining impairment in California Workers’ Compensation cases is fundamental for objective evaluation and rating.  
 
We continue to see incorrect impairment determinations in more than 75% of all medical reports reviewed, frequently within the reports of agreed medical evaluators. Over the past couple of years, the systemic improvement has been eroded by those who don’t seem to want the system to work, especially when it comes to the objective determination of impairment.

To provide an independent, unbiased assessment of impairment and its impact on ADL is the physician’s role. This dissipates when the evaluator is more concerned with the legal impact of the report and/or relationship with the referring parties than with the objective assessment of an injured worker’s condition.
 
The two most impactful events in rating in 2009 were Almaraz-Guzman I and Almaraz-Guzman II. The first decision basically stripped away any objective foundation for both the determination of impairment and disability in California. It essentially made the objective determination of impairment superfluous with the evaluating physician as ‘deux es machina.’ The door was wide open again to rate both subjective and work functional loss without any objective foundation, literally a throwback to pre-2005 Permanent Disability Rating Schedule days where clinical evidence was of little consequence.

Physicians were told that the American Medical Association guides no longer mattered; that a single opinion was enough to bypass the guides and to rate ‘by analogy’ anything they didn’t find to be ‘fair’ (even unsupported complaints). In Almaraz-Guzman II, the Workers' Compensation Appeals Board brought us back to within the "four corners of the AMA guides" and made it binding that the correct AMA Guides rating must always be first.  "Substantial medical evidence" demands correctly calculated impairment ratings under the AMA guides.
 
Evaluators must avoid duplication when considering impairment ratings with the same pathomechanics or etiology. An example is the duplication of shoulder range of motion with shoulder strength deficit impairment, by stating that an individual has significant problems with rotator cuff weakness. Yet, both the ROM and muscle strength deficit have the same etiology (origin). Wikipedia defines the ‘rotator cuff’ as the group of muscles and tendons that act to stabilize the shoulder. However these muscles also control the shoulder’s units of motion (ROM).

“...the impairment due to loss strength could be combined with other impairments only if based on unrelated etiologic or pathomechanical causes.” - AMA guides, pg. 508
 
Looking at the AMA guides as a cohesive whole, principles of rating come to light that are applicable to all impairment determination, even under Almaraz-Guzman II. The opportunity to share this information with industry professionals is what makes the Making Workers’ Compensation Work Conference important for all of us…. I look forward to seeing you there.
 
Luis Pérez-Cordero is an AMA Guides Impairment and California disability rating specialist certified by the American College of Disability Medicine and American Board of Independent Medical Examiners. He will be presenting his ideas at the upcoming Making Workers Comp Work Conference (March 11-12, San Francisco).