Vermont: AMA Guides Are Mandatory for Impairment Rating Purposes–Not Diagnosis of Condition Itself

The Supreme Court of Vermont, in a split decision, recently held that while the AMA Guides (5th Ed.) are determinative with respect to “any determination of the existence and degree of permanent partial impairment” associated with a work-related injury, the Guides do not provide the exclusive mechanism for determining the existence of, or diagnosis associated with, a compensable injury [see Brown v. W.T. Martin Plumbing & Heating, Inc., 2013 VT 38, 2013 Vt. LEXIS 39 (June 21, 2013)]. Applying that holding to the case before it, the court ruled that to the extent, therefore, that Chapter 16 of the AMA Guides purported to establish fixed criteria for diagnosing Complex Regional Pain Syndrome (CRPS)—as opposed to a method for rating the impairment associated with that condition—Vermont’s PPD benefits statute [Vt. Stat. Ann. tit. 21, § 648(b)] did not “imbue those criteria” with the force of law. Accordingly, the workers’ compensation laws did not preclude an impairment rating and associated award of PPD benefits to an injured worker on account of impairment associated with CRPS where the claimant was not diagnosed with CRPS under the criteria listed in Chapter 16 of the Guides, but where a qualified expert confirmed the existence of the condition pursuant to other legally admissible standards sufficient to meet a reasonable medical certainty.  

Claimant, a master plumber, tore the rotator cuff his right shoulder when he slipped and fell down a flight of stairs in 2006. In January 2007, he had surgery to repair the rotator cuff and he subsequently began physical therapy. His recovery was complicated by adhesive capsulitis – inflammation of the shoulder joint causing stiffness and chronic pain – as well as symptoms of CRPS. He sought treatment from a psychiatrist and pain management specialist who affirmed the CRPS diagnosis, relying on the diagnostic criteria from the International Association for the Study of Pain (IASP). The doctor confirmed that the condition was causally related to claimant’s work accident and treated claimant for the CRPS. The doctor then determined that claimant had reached MMI and referred claimant to another physician for an impairment rating. This second physician issued a sixteen-page report in which he accepted the earlier physician’s CRPS diagnosis and assigned a 46 percent whole person impairment rating calculated using the rating process for CRPS in the AMA Guides.

A physician retained by the employer subsequently saw claimant to assess claimant’s permanent impairment. Using the Guides, he concluded that claimant’s CRPS had resolved and assigned a three percent whole person rating to claimant’s shoulder injury on account of range-of-motion limitations and generalized pain. But because he concluded that claimant did not satisfy the diagnostic criteria for CRPS listed in Chapter 16 of the AMA Guides, the employer’s physician did not attribute any impairment for deficits or symptoms associated with CRPS.

At a contested hearing, the Commissioner explained that the AMA Guides and the IASP relied on similar objective signs to support a CRPS diagnosis, but that Chapter 16 of the AMA Guides were more “stringent,” requiring a greater number of those signs to support a CRPS diagnosis, and called for consideration only of observed signs, as opposed to reported symptoms. The Commissioner added that he was compelled to reject the second physician’s opinion as to the 46 percent impairment–not because it was unpersuasive, but because under the particular circumstances of the case, the statute required it. The Commissioner found that while the second physician had used the appropriate mechanism under the AMA Guides for rating impairment associated with CRPS, the CRPS had not been diagnosed in accordance with the criteria outlined in Chapter 16 of the AMA Guides. Accordingly, claimant was not entitled to a rating for impairment associated with CRPS. The Commissioner, therefore, assigned a three percent whole person impairment rating per the employer’s physician’s report.

Upon appeal to the Superior Court, that court also indicated that it was compelled to reject the second physician’s 46 percent rating because 21 V.S.A. § 648(b) provided, “Any determination of the existence and degree of permanent partial impairment shall be made only in accordance with the whole person determination as set out in the fifth edition of the [AMA Guides].” The court found that the AMA Guides Chapter 16 criteria “controls both the diagnosis of impairments and the corresponding computation of the impairment rating,” and that as a matter of law to qualify for a permanent impairment rating “a condition must be diagnosed in accordance with the AMA Guides 5th criteria.”

On further appeal, the supreme court noted that the sole question for review was whether 21 V.S.A. § 648(b) required a factfinder to disallow any permanent impairment rating associated with CRPS where the diagnosis did not comport with the diagnostic standards in Chapter 16 of the AMA Guides. The court answered the question in the negative. According to the court, the language of Vt. Stat. Ann. tit. 21, § 648(b) was clear: that the AMA Guides (5th Ed.) were determinative with respect to any determination of the existence and degree of permanent partial impairment associated with an injury, but the statute did not indicate that the Guides provided the exclusive mechanism for determining the existence of, or diagnosis associated with, a compensable injury. The workers’ compensation laws did not preclude an impairment rating and associated award of PPD benefits to an injured worker on account of impairment associated with CRPS where the claimant was not diagnosed with CRPS under the criteria listed in Chapter 16 of the Guides, but where a qualified expert confirmed the existence of the condition pursuant to other legally admissible standards sufficient to meet a reasonable medical certainty. The superior court’s decision was reversed and the matter remanded.