Overall marked impairment in functionality given 40% impairment rating

May 11, 2012, Kitchener, Ontario

Posted by: Robert Deutschmann, Personal Injury Lawyer

Before: Rosemary Muzzi

Heard: April 20, 2012


Ying-Xiong Huang  was injured in a motor vehicle accident on January 8, 2007. Mr. Huang was struck while riding his bicycle. As a result of this accident, he suffered a compression fracture at L3 of his lumbar spine and also sustained psychological and behavioural impairments.

Mr. Huang applied for and received statutory accident benefits from Primmum, payable under the Schedule including income replacement benefits.

Since he has not been able to return to work, Mr. Huang continues to receive income replacement benefits. For housekeeping services, medical treatment and attendant care services, Mr. Huang has used up the maximum normally available to an insured person. In order to receive further such benefits, Mr. Huang must prove on a balance of probabilities that he has sustained a "catastrophic impairment" as defined in the Schedule.

Mr. Huang applied to Primmum for a determination of catastrophic impairment and underwent a series of assessments at Riverfront Medical Services in April and May 2009. The opinion of the assessment team was that Mr. Huang is not catastrophically impaired.

The parties were unable to resolve this dispute through mediation, and Mr. Huang applied for arbitration at the Financial Services Commission of Ontario under the Insurance Act.

The issues in this hearing are:

1. Is Mr. Huang catastrophically impaired according to section 2(1.2)(g) of the Schedule?
2. Is Mr. Huang catastrophically impaired according to section 2(1.2)(f) of the Schedule?


1. Mr. Huang is catastrophically impaired according to section 2(1.2)(g) of the Schedule.
2. Mr. Huang is not catastrophically impaired according to section 2(1.2)(f) of the Schedule.


At the request of Primmum, Mr. Huang underwent five assessments with Riverfront Medical Services in April and May 2009 to determine whether he had sustained a catastrophic impairment as a result of the accident. These assessments included orthopaedic surgery, in-home occupational therapy, psychiatry, neurology, and optometry assessments. The final opinion of these assessments was that Mr. Huang was not catastrophically impaired under either clause (f) or (g).

Dr. B prepared a rebuttal report for Mr. Huang in August 2009. He did not examine Mr. Huang. Dr. B's report was based on a file review and a critique of the findings and methods employed by the Riverfront team in arriving at its conclusion. Dr. B concluded that Mr. Huang was catastrophically impaired under both clauses (f) and (g) because, respectively, he had a whole person impairment rating of 53%, which could be rounded up to 55%, and had one marked impairment of function.

Riverfront prepared its own rebuttal report in October 2009 where it confirmed its earlier conclusion. Also a further orthopaedic surgery assessment was done in January 2011 resulting in no change to Riverfront's opinion.

Mr. Huang did not testify at the hearing nor did any other witness. There are, as a result, undisputed facts in this case, derived from the documentary evidence presented.

Mr. Huang is married and currently residing with his wife and his daughter and her family (her husband and two children aged 4 and 7). They share a large, two-storey, 4 bedroom house.

Prior to the accident, Mr. Huang appears to have had a regular work and family life. He was employed as a cement molder (lay-up general labour) on a full-time basis. The position was classified as heavy physical demand.  For leisure, Mr. Huang enjoyed swimming, soccer and going to the casino. Mr. Huang's function appeared to be generally unlimited prior to the accident as well: he was independent in his personal care, and in his home maintenance and outdoor maintenance duties. He shared several sets of duties with his wife including: meal preparation and clean-up, housekeeping, and laundry.

The accident caused Mr. Huang physical as well as psychological and behavioural impairments. His physical injuries resulting from the accident are recognized as:

  • a compression fracture of the L3 vertebra of about 40% likely to produce mechanical back pain
  • no more than a minor uncomplicated traumatic brain injury
    pain syndrome
  • tinnitus – without hearing loss

From a psychological perspective, he has been diagnosed with three separate disorders:

  • severe major depressive disorder (single episode)
  • post-traumatic stress disorder – in partial remission
  • pain disorder associated with both psychological factors and a general medical condition

There is no dispute about either the injuries suffered or Mr. Huang's mental or behavioural disorder. The dispute between the parties is particular.

  • What is the class or severity of Mr. Huang's functional impairment due to his mental or behavioural disorder?
  • What is the degree of his whole person impairment? With respect to this issue, the parties also disagree about whether his impairment due to his mental or behavioral disorder is to be counted in assessing his whole person impairment.



Issue 1
Is Mr. Huang catastrophically impaired according to section 2(1.2)(g) of the Schedule?

The Arbitrator found that Mr. Huang is catastrophically impaired according to section 2(1.2)(g) of the Schedule because he has marked impairment on account of his mental or behavioural disorders.

Under this clause of the Schedule, a catastrophic impairment includes an impairment that, in accordance with the American Medical Association's Guides to the Evaluation of Permanent Impairment, edition, 1993, results in a class 4 impairment (marked impairment) or class 5 impairment (extreme impairment) due to mental or behavioural disorder. To assess the class of mental or behavioural impairments under the Guides, four aspects of functional abilities are considered: (1) activities of daily living (ADLs); (2) social functioning; (3) concentration, persistence and pace (c.p.p.); and (4) deterioration or decompensation in work or work like settings (also referred to as "adaptation").

The Riverfront assessors and Dr. B agree on the degree of Mr. Huang's impairment in each of the four areas of function they assessed: (1) mild impairment in ADLs; (2) moderate impairment in social functioning; (3) moderate impairment in c.p.p.; and, (4) marked impairment in adaptation. They disagree about his overall impairment: the Riverfront assessors find him to be moderately impaired whereas Dr. B concludes that he is markedly impaired.

The Arbitrator found that that Mr. Huang has a moderate impairment in ADLs, social functioning and c.p.p. and a marked impairment in adaptation. Even if the Arbitrator had agreed with the assessors that his ADLs impairment is only mild, having undertaken an assessment of Mr. Huang's overall impairment he referred to Aviva Canada Inc v. Pastor (2011 IBSC 2164) in which the court specifically stated that a finding in accordance with the Guides requires a finding of impairment resulting from an overall assessment of all four of the areas of functioning. The Guides demonstrate a process of analysis that requires taking into account all four areas of function. The Guides are not concerned with impairment of a function but the life of a person as a whole.  The Arbitrator found that Mr. Huang has a marked impairment in function on account of his mental or behavioural disorder. The evidence indicates that the serious mental disorders from which Mr. Huang suffers have impeded his abilities to a marked degree when all four areas of function are assessed given that a marked class of impairment is defined in the Guides as a level of impairment that significantly impedes useful functioning.

The Guides remind us that it is important not to confuse the seriousness of a diagnosis with the level of impairment because a person can be diagnosed with a serious condition but have little or no impairment of function. In Mr. Huang's case, the psychiatric diagnoses are serious and his illnesses affect numerous crucial daily functions to the extent that there is significant impairment of function in all areas.

Mr. Huang's level of impairment in his activities of daily living (ADLs)

Dr. Z conducted the psychiatric assessment. He found that Mr. Huang suffered from severe major depressive disorder; post-traumatic stress disorder – only partly in remission; and a pain disorder associated with both psychological factors and a general medical condition. He also noted that Mr. Huang's depression is not being controlled by medication. An occupational therapist (OT), RG, also assessed Mr. Huang's function in April 2009.

Dr. Z's assessment of Mr. Huang's impairment in his activities of daily living (ADLs) rated the impairment due to psychological factors (such as anxiety and depression) as mild only. The Arbitrator disagreed.

The Arbitrator found that Mr. Huang's ability to engage in his usual daily activities has been significantly decreased as a result of the psychological illnesses he suffered as a result of the accident. His impairment in this regard is more correctly described as moderate – compatible with some but not all useful functioning.

In concluding that he has a moderate impairment in his ADLs, the Arbitrator considered all of Mr. Huang's function related to ADLs including the functional limitations owing to pain and depression-related fatigue or lack of motivation. In the Arbitrator’s view, the effects of both the depression and the psychological component of the diagnosed pain disorder contribute considerably to Mr. Huang's limitations in ADLs.

Both assessors noted Mr. Huang's limitations in function as follows.

Mr. Huang uses a single point cane for walking, is unable to walk for more than 15 minutes, unable to ride a bicycle or use public transit, has difficulties with sitting for longer than 10 minutes, is unable to do meal preparation, housekeeping, laundry, or home maintenance, and no longer engages in regular sporting activities. He reported independence with personal care and generally manages on his own, slowly, but needs help with lower extremity dressing and putting on heavy or large coats, and also makes use of external supports and aids. He has not worked since the accident. The occupational therapist also noted that he has moderate difficulties with respect to his awareness of home and safety, though he could use the telephone and access required phone numbers. In general his overall time for processing information was slow and at times he needed cueing.

In addition, Mr. Huang also suffers from a host of limiting, if not in some cases debilitating, symptoms on account of his mental or behavioural disorders, including

  • panic attacks two to three times per day lasting 5 to 6 minutes
  • frequent nightmares (these have decreased in intensity since after the first few months after the accident)
  • continuing sleep disturbances
  • ruminations about the accident monthly
  • crying twice a week

Moreover, and more generally, Mr. Huang is also subject to depressive symptomatology including pessimism, loss of pleasure, significant feelings of guilt and punishment, self-dislike, hopelessness and passive suicidal ideation (particularly six months after the accident). He experiences restlessness and agitation; concentration difficulties; significant fatigue and diminished energy; diminished libido; indecisiveness; significant feelings of worthlessness; and feelings of being "imprisoned."

Both Dr. Z and the OT appear to have minimized the effect of the depression, and the psychological component of the pain disorder, on Mr. Huang's level of impairment. For example, Dr. Z found that Mr. Huang's inability to ambulate and most of Mr. Huang's impairment in the area of ADLs generally was due to chronic pain rather than depressive symptomatology affecting his motivation. The OT concluded generally that he was limited in several aspects of daily life due to pain and decreased stamina affecting his motivation. They seem to focus on these limitations as being caused by pain resulting from Mr. Huang's physical injuries. Nevertheless, at the same time, they noted that Mr. Huang's lack of capacity was due in part to motivation issues and depression-related fatigue.

In the Arbitrator’s view, the assessors incorrectly disregarded the effect of the psychological component of pain and downplayed the contribution of the depression to Mr. Huang's functional abilities. The evidence of Mr. Huang's diagnoses, symptoms, and functional limitations taken together with the recognition that his lack of engagement and capacity is related to depression and pain leads me to find that his impairment in this area is very much related to mental or behavioural disorders as well as his physical injuries. Further, the evidence of his psychological symptoms and his abilities leads me to conclude that Mr. Huang's degree of impairment in this area on account of his mental disorder is moderate rather than mild.

Even if the Arbitrator is wrong in characterizing Mr. Huang's ADLs impairment as moderate, the Arbitrator would still conclude that he has a marked impairment overall because the mild impairment in respect of his ADLs according to the evidence before the Arbitrator is at least at the high end of the range for mild impairment. In addition, there is other evidence that overall Mr. Huang's impairment on account of his mental or behavioural disorder is marked as canvassed below.

Mr. Huang's level of overall level of impairment on account of a mental or behavioural disorder

As canvassed above, Mr. Huang's depression-related symptoms are considerable and he suffers from them on a regular basis. Moreover, the details noted in both the psychiatric and the occupational therapy assessments indicate that Mr. Huang is as a result very limited in all of his activities; daily, social and work-related. The overall picture of Mr. Huang's life is one of very limited function.

In respect of social function, Dr. Z noted that Mr. Huang's impairment is moderate because he has experienced a significant decrease in his capacity for enjoyment and interpersonal engagement due to anxiety and depression and chronic suicidal ideation. The occupational therapist noted that he no longer engages in sports and does not play soccer. She stated that his performance on the social adjustment part of testing indicates low performance, suggesting that he does not feel good about himself, does not feel like talking to friends or socializing and is overall socially withdrawn.

While Dr. Z found that Mr. Huang's impairment in concentration and memory would not exceed mild, Dr. D in his summary concluded that Mr. Huang had a moderate impairment in this regard and the evidence supports this finding. It appears from the evidence that Mr. Huang spends an inordinate amount of time in bed and/or watching TV and movies and listening to/watching the news. While he reads the newspaper and has helped his daughter babysit his grandchildren on occasion, there is very little evidence that he can focus on other tasks.

In the area of adaptation, Dr. Z found that Mr. Huang had a marked level of impairment and his detailed commentary in this regard paints a clearer picture of significant limitation. Mr. Huang can no longer work due to chronic pain and his self-esteem and self-image was tied to his work. He has not adapted to his impairment as regards his personal care and household responsibilities. While Dr. D's neurological assessment [See note 9 below] uncovered only a mild brain injury, Dr. D concluded that Mr. Huang has cognitive inefficiencies that were explained by pain, sleep disruption, psychological duress and medication effect, all of which appear to have resulted from the accident or its effects.

In the Arbitrator’s view, the Riverfront assessors' findings demonstrate that Mr. Huang's everyday function is greatly impeded. Mr. Huang's depression has had a significant, negative impact on his entire life and contributed a great degree to his inability to function in all areas of his life.

Consequently, the Arbitrator found that Mr. Huang has a marked impairment due to a mental or behavioural disorder and is therefore catastrophically impaired according to section 2(1.2)(g) of the Schedule.

Issue 2
Is Mr. Huang catastrophically impaired according to section 2(1.2)(f) of the Schedule?


The Arbitrator found that Mr. Huang is not catastrophically impaired according to section 2(1.2)(f) of the Schedule. Under section 2(1.2)(f), a catastrophic impairment includes an impairment that, in accordance with the Guides results in 55 per cent or more impairment of the whole person.

In the past, there has been some debate about whether some measure of mental/behavioural impairment can be included as part of the assessment under section 2(1.2)(f) and, if so, the methodology for calculating a percentage whole person impairment (WPI) rating based on mental or behavioural impairment.

Recently, the Ontario Court of Appeal considered this question in the case of Kusniersz (Kusnierz v. Economical Mutual Insurance Company, 2011) and concluded that that the combination of physical and psychological impairments is appropriate under clause 2(1.1)(f) of the Schedule. The court goes on to state "that the plain language of cl. 2(1.1)(f) seems to suggest that combination of both kinds of impairment is possible. Second, the purpose of the Guides supports combination." One of the Guides' aims is to assess the "total effect of a person's impairments on his or her everyday activities. An objective, standardized system of assessment is only useful to the extent that it can reflect persons' actual levels of impairment. To disregard the mental and behavioural consequences of a person's injuries because they are too hard to measure would defeat the purpose of the Guides."

In fact, the Riverfront assessors did assess Mr. Huang's impairment under clause (f) by combining the percentage rating for his physical impairments (10%) with a rating for the impairment caused by his mental or behavioural disorder to arrive at an overall WPI. They found the WPI rating for his moderate psychological impairment to be in the range of 15-29%. When combined with the 10% physical rating according to the Combined Values chart in the Guides, they arrived at an overall WPI rating of between 24-36%, well below the threshold of 55% mandated in the Schedule.

The disputes between the parties in respect of the determination under clause (f) are two: (1) what is the correct percentage rating to be assigned to both the physical impairments and the psychological impairment; and, (2) what is the method to be used for calculating those percentage ratings?

WPI rating for physical impairment

The Arbitrator disagreed with Mr. Huang that Dr. D's approach to determining the WPI percentage rating on the physical impairment was flawed. Dr. D gave reasons in his summary for which he did not rate other apparent physical problems at more than 0%. Dr. B, on the other hand, did not directly assess a percentage rating for the other physical impairments, and instead appears to have accepted and used Dr. D's 10% WPI rating in his own calculations.

From this the Arbitrator concluded that Dr. D's approach is reasonable and there being no other evidence about the appropriate percentage to be assigned, the Arbitrator accepted Dr. D's WPI rating of 10% for Mr. Huang's physical impairments.

WPI rating for impairment on account of mental or behavioural disorder

There is no clear method for the calculation of a WPI rating for mental or behavioural impairments. The Guides do not provide a specific methodology for assigning a WPI rating for impairments on account of mental or behavioural impairments; hence the conversion from a categorical rating (i.e., mild, moderate, etc.) to a percentage rating can be somewhat arbitrary or artificial.

The Court in Kusnierz did not endorse a particular or specific method for arriving at a percentage rating for a mental or behavioural disorder impairment. In fact, the Court recognized that such calculation would be difficult:

Respectfully, I do not read the Guides, or the SABS, as articulating a policy position against combination. Although the Guides do warn against assigning percentages to non-neurological psychiatric impairments, there are, as discussed above, a number of indications that combination may be permissible under certain circumstances. (emphasis added in bold)

Further, the 55% WPI threshold for catastrophic impairment is a creation of Ontario's legislation and is a requirement only of the Schedule. The Guides do not speak of catastrophic impairments. Moreover, the Guides themselves do not assign any special status to a 55% WPI rating.

Consequently, the exercise of assigning WPI ratings to psychological impairments and combining these ratings with those for physical impairments can create some anomalous and strange results.

In this case, for example, while the Arbitrator found that Mr. Huang has a marked impairment on account of a mental or behavioural disorder such that he meets the definition of a catastrophic impairment under (g), his impairments, when assigned a percentage and combined under (f), do not meet the 55% WPI threshold. This is the case for two reasons essentially. First, Mr. Huang's physical impairment WPI rating is low. Second, the conversion of Mr. Huang's marked psychological impairment to a WPI rating results in a range wherein, given the facts of this case, he falls in the middle. The result is that the combination of the two kinds of impairments does not amount to 55%WPI.

The Riverfront assessors used a limited approach, based on the Guides, but not a completely accurate method for converting the categorical rating to a percentage rating. In assigning a WPI percentage, Dr. D used Table 3 in the Guides. This table references the effects of objectively defined neurological impairment(s) of the central nervous system on emotional function, measuring impairment of social function. However, Dr. D uncovered "no more than a minor uncomplicated traumatic brain injury." Mr. Huang's impairment therefore is not necessarily a neurological impairment. Further, four functions, rather than simply social function, are to be addressed when assessing impairment based on a mental or behavioural disorder. Dr. B used the Global Assessment of Functioning (GAF) scale and converted Mr. Huang's GAF score of 41 to a WPI percentage by using a schedule from the State of California. He found a WPI of 48% by using this method, but this method is neither recognized in the Guides nor in the Schedule.

The Arbitrator preferred the approach taken by a Commission Arbitrator in the case of Jaggernauth and Economical Mutual Insurance Company, FSCO 2010. The arbitrator explored the dilemma and analyzed the Guides and existing jurisprudence thoroughly. He agreed with the preponderance of the jurisprudence that determination of a WPI rating for mental or behavioural impairment done in accordance with the Guides would rely heavily upon the ratings that are actually referred to within the text of the Guides. He also used every other measure of impairment in evidence before him to assist in arriving at a WPI rating for mental or behavioural disorder impairment in accordance with the Guides.

In choosing a percentage impairment rating in that case, the arbitrator kept in mind several significant measures of impairment all found within the Guides:

  1. The range of WPI ratings given in Table 3 from Chapter 4
  2. The range of WPI ratings referenced at p. 301 of the Guides (25-50%) ought also to be considered.


The Arbitrator also considered the applicant's GAF score and the categorical ratings for impairment in each of the four areas of function assessed under clause 2(1.2)(g).

Applying this fulsome approach to the determination in Mr. Huang's case, the Arbitrator found that an appropriate percentage rating for WPI for his mental or behavioural disorder is 40%. As explained earlier, the calculation of a WPI percentage rating is not an exact science. It requires an assessment of the evidence of a person's function considered in the context of the Guides and the rational use of the tools provided therein.

Using Table 3, Chapter 4, at page 142 of the Guides to convert Mr. Huang's overall categorical rating of marked, the percentage impairment rating indicated there provides a range from 30 to 49%. Table 3 specifies that this range is severe and means impeding useful action in almost all social and interpersonal daily functions. In the table for the classification of impairment due to mental and behavioural disorders, a marked impairment is defined in the Guides as one that significantly impedes useful functioning.  In the Arbitrator’s view, the range in Table 3 includes cases where the impairment is more severe than that which we see with Mr. Huang.

Also, within his overall rating of marked, Mr. Huang is impaired to a lesser degree in respect of other specific functions; that is, Mr. Huang is rated at having a moderate impairment in ADLs, concentration, pace and persistence, and social function with a marked impairment in adaptation only. In general, therefore, the Arbitrator would rate him at the medium level within the range of marked impairment. This conforms in my view also with his GAF score of 41. For these reasons, the Arbitrator found it appropriate to rate Mr. Huang's WPI for a mental or behavioural disorder at 40%.

Using the Combined Values chart in the Guides, the combination of 40% WPI for Mr. Huang's psychological disorder and 10% WPI for his physical impairment amounts to a total WPI of 48%, which is still a significant impairment but insufficient to meet the criteria in section 2(1.2)(f).

Consequently, Mr. Huang is not catastrophically impaired as defined in section 2(1.2)(f) of the Schedule.


Posted under Accident Benefit News, Automobile Accident Benefits, Bicycle Accidents, Brain Injury, Car Accidents, Catastrophic Injury, Chronic Pain, Fractures, Pain and Suffering, Treatment

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