Evaluation Of Permanent Impairment Research Articles

Artificial Intelligence in Evaluation of Permanent Impairment: New Operational Frontiers.

Artificial intelligence (AI) and machine learning (ML) span multiple disciplines, including the medico-legal sciences, also with reference to the concept of disease and disability. In this context, the International Classification of Diseases, Injuries, and Causes of Death (ICD) is a standard for the classification of diseases and related problems developed by the World Health Organization (WHO), and it represents a valid tool for statistical and epidemiological studies. Indeed, the International Classification of Functioning, Disability, and Health (ICF) is outlined as a classification that aims to describe the state of health of people in relation to their existential spheres (social, family, work). This paper lays the foundations for proposing an operating model for the use of AI in the assessment of impairments with the aim of making the information system as homogeneous as possible, starting from the main coding systems of the reference pathologies and functional damages. Providing a scientific basis for the understanding and study of health, as well as establishing a common language for the assessment of disability in its various meanings through AI systems, will allow for the improvement and standardization of communication between the various expert users.

Observed Errors in Lower Extremity Impairment Rating: Recognition and Prevention

Abstract Impairment evaluations not performed following processes defined in the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides) usually result in erroneous ratings. Common lower extremity impairment rating (IR) errors include using the diagnosis-based approach for more than one diagnosis within a region, and incorrectly assessing gait abnormalities, motion loss, nerve injuries, and complex regional pain syndrome. Rigorous adherence to the AMA Guides methodology and recognition of common IR errors can prevent the promulgation of erroneous impairment ratings.

Observed Errors in Upper Extremity Impairment Rating: Recognition and Prevention

Abstract Impairment evaluations not performed following processes defined in the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides) will result in erroneous ratings. Common errors in impairment rating (IR) for upper extremity are frequently seen in physician IR reports and independent medical examination reports. Recognizing these errors can result in the prevention and management of these ratings. Common errors include rating impairment using the diagnosis-based approach for more than one diagnosis within a region and making incorrect assessments of motion loss, nerve injuries, entrapment disorders, and complex regional pain syndrome.

Cognitive Screening Tools

Abstract Physicians performing impairment evaluations on patients with cognitive complaints and possible central nervous system disorders should perform a clinical mental status assessment. Assessing cognitive complaints efficiently, in a systematic and supportable way, can be challenging. The AMA Guides to the Evaluation of Permanent Impairment specifies that objective criteria are important to consider when assessing impairment. Physicians may choose to use standardized cognitive screening tests (cognitive screeners) as a relatively quick, practical tool to initially assess patients and aid in decision making. Several cognitive screeners will be discussed in detail below. A patient's performance on such tests may indicate that more comprehensive testing is needed. Cognitive screeners have limitations and are not designed to assess symptom validity or the extent to which psychological factors may contribute to cognitive complaints. Comprehensive neuropsychological assessment may be indicated in these situations and when the screeners demonstrate findings of potential concern help define MMI.

COVID-19: Achieving Maximum Medical Improvement and Assessing Permanent Impairment

Abstract Patients with coronavirus disease 2019 (COVID-19) may have persistent symptoms beyond the normally expected illness resolution. This disease was not diagnosed before late 2019, and therefore, we have more limited experience in understanding all of its outcomes. Thus, clinical, functional, and permanent impairment assessment is challenging. Symptoms including fatigue, dyspnea, and cognitive difficulties have been referred to as “post-acute COVID,” “long COVID,” or “long haulers.” Patients who present for assessment of causation, maximum medical improvement (MMI), and permanent impairment can be challenging. For some examinees, after 6 to 12 months without outgoing improvement and with appropriate investigation, treatment, and rehabilitation, the examinee can be considered at MMI. However, because this disorder is new and appropriate treatment may be unclear, the time to achieve MMI is less certain. Physicians may use approaches in the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), to help define MMI. As science evolves, so will our understanding of how to evaluate chronic problems associated with COVID-19.

Rating Repeat Partial Meniscectomies, Unoperated Meniscal Tears, and Meniscal Repairs

Abstract Rating repeat partial meniscectomies, unoperated meniscal tears, and meniscal repairs requires thoughtful clinical assessment and application of directives provided in the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides). Although the AMA Guides provide a specific impairment value for a partial meniscectomy, repeat meniscectomies may result in further impairment not to exceed the maximum value assigned for a total meniscectomy.

AMA Guides, Sixth Edition: Conceptual Foundations and Philosophy

Abstract This article provides an overview of the conceptual foundations of the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Sixth Edition. Impairment assessment in the sixth edition underwent a “paradigm shift” compared to the AMA Guides, Fifth Edition, in which its impairment rating methodology is based on the World Health Organization's (WHO's) International Classification of Functioning, Disability and Health (ICF) framework. Impairment rating is but one of several determinants of disability, and the one most amenable to physician assessment.

Fundamentals of Maximum Medical Improvement

Abstract This is a brief introduction to maximum medical improvement (MMI), which is pertinent to permanent impairment assessment. The definition and explanation of MMI according to the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Sixth Edition, is discussed.

Catastrophic Central Nervous System Injury Rating

Abstract We present a case involving a catastrophic injury that resulted from a completely obstructed airway when an examinee choked on food. She had cardiopulmonary arrest and developed a hypoxic-ischemic encephalopathy associated with profound neurological losses. The evaluation of the consequences of severe central nervous system injury necessitates evaluation and rating of all the sequelae of that injury. The first step is clinical assessment, followed by thoughtful application of these data to the processes and criteria provided in the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides). The approaches discussed in the fifth and sixth editions of the AMA Guides are similar.

Entrapment Neuropathies: Electrodiagnostic Criteria

Abstract Like the diagnosis-based impairment (DBI) method and the range-of-motion (ROM) method for rating permanent impairment, the approach for rating compression or entrapment neuropathy in the upper extremity (eg, carpal tunnel syndrome [CTS]) is a separate and distinct methodology in the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Sixth Edition. Rating entrapment neuropathies is similar to the DBI method because the evaluator uses three grade modifiers (ie, test findings, functional history, and physical evaluation findings), but the way these modifiers are applied is different from that in the DBI method. Notably, the evaluator must have valid nerve conduction test results and cannot diagnose or rate nerve entrapment or compression without them; postoperative nerve conduction studies are not necessary for impairment rating purposes. The AMA Guides, Sixth Edition, uses criteria that match those established by the Normative Data Task Force and endorsed by the American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM); evaluators should be aware of updated definitions of normal from AANEM. It is possible that some patients may be diagnosed with carpal or cubital tunnel syndrome for treatment but will not qualify for that diagnosis for impairment rating; evaluating physicians must be familiar with electrodiagnostic test results to interpret them and determine if they confirm to the criteria for conduction delay, conduction block, or axon loss; if this is not the case, the evaluator may use the DBI method with the diagnosis of nonspecific pain.

Spinal Alteration of Motion Segment Integrity Using the Sixth Edition

Abstract Spinal impairment evaluation includes determination of the presence or absence of alteration of motion segment integrity (AOMSI). The diagnosis-related estimate (DRE) method is the principal methodology used to evaluate spinal AOMSI impairment in the fourth and fifth editions of the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides). In the AMA Guides, Sixth Edition, impairment ratings are calculated using the diagnosis-based impairment (DBI) method that uses five impairment classes determined by diagnoses and specific criteria, adjusted by consideration of non-key factors and grade modifiers. This article includes a correction of numbers in the AMA Guides, Sixth Edition, Figure 17-6. The following factors must be considered to determine if AOMSI is present: 1) flexion/extension radiographs are performed when the individual is at maximum medical improvement and are technically adequate; 2) the proper methodology is used in obtaining measurements of translation and angular motion; 3) normal translation and angular-motion thresholds consistent with the literature are used in determining AOMSI. Imaging modalities such as videofluoroscopy, digital fluoroscopy, and upright/motion magnetic resonance imaging cannot be used to establish an AOMSI permanent impairment using the AMA Guides. A number of technical factors can affect the image quality associated with measurements of AOMSI, including film centering, artifacts, poor edge resolution, endplate normal variations and spurring, and use of analog rather than digital radiography.

Range of Motion Extremity Evaluation: Sixth Edition Approaches

Abstract Examiners use range-of-motion (ROM) testing to help calculate the physical examination modifier when they use the diagnosis-based impairment (DBI) method in the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Sixth Edition. DBI is the preferred method for calculating upper and lower extremity ratings, but, in instances specified by the regional grid, the evaluator may choose to use the ROM method, typically because it yields a higher impairment rating relative to the DBI method. In rare lower-limb cases when the injury is not fully articulated by the regional grid (eg, severe crushes, burns, and scarring), ROM may be used instead of diagnosis. In cases of amputation, ROM may be used for the remaining portion of the limb and combined with amputation rating as explained in sections of Chapter 15. Note that, in the AMA Guides, the extended anatomic position is 0° rather than 180°, and evaluators can consult the detailed diagrams of the planes of the thumbs, fingers, wrists, elbows, and shoulders. Invalid results are declared if, after three consecutive efforts, the three measurements for a given plane of motion vary more than 10° from the mean (average) of these three measurements. The article also discusses adjustments for functional history when the ROM method does not adequately capture the full impairment.

Impairment of Face-, Nose-, and Throat-related Structures Sixth Edition Approaches

Abstract Facial disfigurements, including those caused by burns (thermal, chemical, or electrical) or trauma, are rated in the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Sixth Edition, Chapter 11, which also discusses occupational overexposure to sunlight, airborne chemicals, heavy metals, and allergens that may lead to head and neck cancers and degraded ability to breathe, chew, swallow, smell, or speak. Additional relevant impairments include those of olfaction and taste, chewing and swallowing, voice and speech, and of the upper respiratory passages. For upper air passage defects and voice and speech impairments, the evaluator assigns an impairment rating by selecting the relevant table or grid in Chapter 11 and then assigning the appropriate impairment class, as determined by the key factor. The patient's history is the key factor for upper air passage deficits, and the performance measures of audibility, intelligibility, and functional efficiency collectively act as the key factor for voice and speech impairments. Once they select an impairment class, evaluators can modify the rating within the impairment class by considering remaining variables. When rating the patient's ability to smell and taste or chew and swallow, raters do not use impairment classes or modifiers. Rather, they assign impairment within an allowable range largely based on professional judgment complemented by objective findings and a well-documented rationale.

Amputation Evaluation: Sixth Edition Approaches

Abstract Upper extremity amputations are rated in the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Sixth Edition, Section 15.6, Amputation Impairment, where text, tables, and figures guide evaluators in combining proximal diagnosis-based impairments (DBIs) and proximal range-of-motion impairments. The AMA Guides provides impairment grids for lower and upper extremity amputations, which are divided into five impairment classes (0 through 4), and each impairment class is further divided (except class 0) into five grades (A through E), each with its respective impairment rating that is expressed as a percentage of the extremity. Determining impairment class, and thus the default value of impairment, is straightforward if the amputation occurred directly at one of the points in the relevant grid; if the amputation occurred at another point, the evaluator should consult the appropriate figure to assess how the specific level of amputation corresponds with impairment percentages. An individual's proximal problems may lead to an increase in the impairment value because of the application of grade modifiers. Except in rare instances of bilateral upper extremity amputation or when the patient is unable to wear a prosthesis for a lower extremity amputation, the evaluator usually uses the default rating value within the selected impairment class as the final percentage rating. Evaluators are advised to re-read the amputation section in the AMA Guides before conducting an amputation evaluation.

Effects of Aging on Impairment Ratings: Part 3: Neurological and Associated Issues

Abstract This article is the third in a series of four that explore the effects of age-related changes in impairments as defined by the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fifth and Sixth Editions. Specifically, this article focuses on evaluation of disturbances of the nervous system, divided for discussion here into four parts—the central nervous system (CNS), the peripheral nervous system, vision, and hearing—and offers guidance in using the AMA Guides, Fifth and Sixth Editions, in a variety of specific disorders within each group. For example, the CNS discussions address disorders of consciousness and awareness; sleep and arousal disorders; alterations in metal status, cognition, and highest integrative function; aphasia or dysphagia; emotional or behavioral disorders resulting from CNS causation (fifth edition only); chronic pain; and others. One of the most challenging issues in evaluating peripheral neuropathy regards carpal tunnel syndrome, and rating physicians should provide references in their reports to justify their position. Rating visual problems usually requires attention to the medical records to document preinjury visual status. The AMA Guides, Fifth and Sixth Editions, do not use age-adjusted corrections in assessing age-related diminished hearing, but local jurisdictions and circumstances may apply apportionment. In apportioning impairment due to aging, the examiner must understand both the science and the specific legal processes involved.

Effects of Aging on Impairment Ratings: Part 2: Internal Medicine Issues

Abstract This is the second of four articles that explore the effects of age-related changed in impairment evaluations according to the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fifth and Sixth Editions; specifically, this article completes the review of the internal medicine sections. With respect to the digestive system, the normal aging process affects gastrointestinal impairment ratings as found in the AMA Guides, Fifth and Sixth Editions, for gastroesophageal reflux disease, peptic ulcer disease, pancreatitis, diverticulitis, irritable bowel syndrome, fecal incontinence, and hemorrhoids. Cancers of the digestive system and infectious hepatitis were reviewed by the National Institutes of Health in The Burden of Digestive Diseases in the United States (2008), which should be reviewed when an impairment rating or apportionment is needed or for an individual with these conditions alleged to be the result of a compensable injury or illness. The normal aging process does not significantly affect the impairment ratings for renal disease (upper urinary tract disease), but, for individuals over 70, an age adjustment should be incorporated into the impairment rating. The AMA Guides, Fifth and Sixth Editions, also do not provide age-related modifications for urinary incontinence, but a rating physician may apply a discretionary apportionment. For diseases of the scrotum, testicles, epididymis, and spermatic cord, as well as for prostatic hypertrophy, neither edition of the AMA Guides makes age-related modifications; neither are modifications because of aging are made for the female reproductive tract, although raters are told to consider the physiological differences.

Do Low-Speed Vehicle Collisions Cause Intervertebral Disc Degeneration or Herniation?

Abstract Complaints of spinal pain are common after motor vehicle collisions (MVCs), and evaluators may be asked whether the collision caused permanent injury to the spine, including aggravating intervertebral disc degeneration (IDD) and/or causing a disc herniation. To determine causality, evaluators can use the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides) to understand if a low-speed collision caused IDD. Injury causation analysis (ICA) is the scientific method used to analyze the mechanism and magnitude of injury for people who experience an MVC. ICA involves comparing the mechanical forces involved in the incident with the body's injury tolerance. Low back pain (LBP) is a common complaint following MVCs, but the literature regarding automobile collision testing has been compared to the body of evidence regarding real-world collision data and shows that, for low-speed impacts, any injuries are minor and self-limiting. Further, disability due to LBP was predicted by an abnormal baseline psychological test profile or a previously disputed compensation claim. The motions, forces, and accelerations generated in low-speed collisions are less than those encountered in activities of everyday living. ICA suggests that disc degeneration and disc herniations are pre-existing and are not caused by low-speed MVCs. Although the pain caused by a muscle sprain associated with a low-speed collision may prompt imaging studies that show disc pathology, these are coincidental and are not causally related.

Effects of Aging on Impairment Ratings: Part 1: Internal Medicine Issues

Abstract This article is the first of four to explore the effects of age-related changes in impairment evaluations as defined by the fifth and sixth editions of the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides). With respect to the cardiovascular system, impairment ratings for the following conditions commonly are affected by the aging process: coronary artery disease, valvular heart disease, arrhythmias/dysrhythmias, hypertension, and peripheral vascular disease. Impairment ratings in the fifth and sixth editions of the AMA Guides for the pulmonary system apply corrections for age with respect to certain measurements such as forced vital capacity. The normal aging process does not significantly affect impairment ratings for either hematological impairments or the endocrine system, nor does normal aging significantly affect the impairment ratings for mammary glands. With careful attention to the diagnosis and causative factors, evaluators may find that the normal aging process can affect impairment ratings associated with metabolic bone disease. Evaluating physician typically must determine impairment secondary to a specific cause (eg, injury or exposure) and therefore must consider if other factors are contributing to the impairment.

Predictive Validity of the Neuropsychological Assessment Battery-Screening Module for Assessing Real-World Disability in Patients with Mild Traumatic Brain Injury

The present study set out to examine the ecological validity of the Neuropsychological Assessment Battery-Screening Module (NAB-S) and to examine more specifically, whether performance on this test battery is related to real-world disability status in patients who have sustained a mild traumatic brain injury (mTBI) as a consequence of a motor vehicle collision (MVC). Seventy-nine patients were recruited from a random sample of litigating patients who incurred an mTBI and were referred for a neuropsychological examination due to subjective complaints of cognitive function. Of the total sample, 54 patients were categorized into the non-disabled group and 25 patients were categorized into the disabled group using the 4th edition of the American Medical Association (AMA) Guides to the Evaluation of Permanent Impairment (AMA; 1993). A multivariate analysis of variance revealed that performance on the NAB-S significantly differed between the two groups, and that memory and attention domains provided a more discriminative index of disability than general neuropsychological functions. In addition, discriminant function analyses revealed that the NAB-S correctly classified 73% of patients according to their group membership. The current findings provide evidence for the ecological validity of the NAB-S as a reliable index of real-world disability status as defined by the AMA Guides.

Somatization

Abstract An evaluator's failure to recognize illness behavior and to adjust for its effect on symptom presentation can lead to erroneous conclusions regarding impairment or disability; here the authors review the associated phenomena of somatization, disorders that arise from it, and factors that contribute to somatization. Somatization is an individual's unconscious use of the body or bodily symptoms for psychological purposes or psychological gain. As the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Sixth Edition, notes, somatization is a “tendency to experience and report somatic complaints (physical symptoms) in response to psychosocial stress and seek health care services for them.” The AMA Guides also advises evaluators that “exclusion or inclusion of somatization disorder, factitious disorder, and/or malingering must be done with care.” A table lists developmental factors that may dispose to somatization (eg, somatizers are present in the family of origin, or coping mechanisms other than illness behavior are absent or unacceptable); a second table compares disorders that may involve somatization. Somatization is prevalent in clinical practice and is likely to occur with equal, or higher, frequency in the evaluation setting. The presence of somatization distorts symptom presentation and can exert a confounding effect on impairment assessment methodologies that rely on the accuracy of patients’ self-presentations.