Decision #14/21 - Type: Workers Compensation


The worker is appealing the decision made by the Workers Compensation Board ("WCB") that their permanent partial impairment rating of 2.89% has been correctly calculated. A file review was held on January 14, 2021 to consider the worker's appeal.


Whether or not the worker’s permanent partial impairment rating of 2.89% has been correctly calculated.


The worker’s permanent partial impairment rating of 2.89% has been correctly calculated.


The WCB accepted the worker’s claim for a right shoulder injury that occurred at work on October 24, 2017. The injury was initially diagnosed as a soft tissue injury, but an MRI study of December 1, 2017 revealed “Multifocal areas of articular surface and interstitial tearing…without evidence of a definite full-thickness tear. Partial substance tearing of the subscapularis and longitudinal tearing of the long head of biceps. There is glenohumeral and AC (acromioclavicular) joint osteoarthritic change. There is associated degenerative labral tearing.” On December 1, 2018, the worker underwent an arthroscopy, debridement of the humeral head, debridement of the labral tear, subacromial decompression and repair of an inferior Bankart lesion. Post-surgery, the worker continued to receive physiotherapy and attended follow-up appointments with his orthopedic surgeon.

A WCB medical advisor reviewed the worker’s file on June 20, 2019, noting the worker’s recovery had not been satisfactory but that it was unlikely any further therapeutic interventions would improve the worker’s status. Following consultation with the WCB physiotherapy consultant, the WCB medical advisor provided the employer with the worker’s permanent restrictions on June 26, 2019. The employer was unable to accommodate the worker’s permanent restrictions and the WCB then commenced providing vocational rehabilitation services to the worker.

On November 4, 2019, a WCB medical advisor noted “Limited range of motion of the shoulder has been described on the file in spite of extensive physiotherapy” and that the worker had reached maximum medical improvement. The medical advisor recommended the worker be evaluated for a permanent partial impairment rating and award, noting the worker had major pre-existing conditions and that his mobility deficits are a result of both the compensable injury and the pre-existing conditions.

The worker was assessed for a permanent partial impairment rating on January 30, 2020. Based upon the findings from that assessment, a WCB medical advisor provided a memorandum to file on March 3, 2020 noting no muscle wasting or weakness was noted at the examination and providing a 5.8% permanent partial impairment rating, which was reduced by 50% due to the worker’s pre-existing condition, to 2.9%. On March 24, 2020, the WCB advised the worker the permanent partial impairment (PPI) rating was 2.9% and the worker was provided with a monetary award.

The worker requested reconsideration of the WCB’s PPI rating and award to Review Office on April 23, 2020. The worker noted their mobility was not the same as it was prior to the workplace injury and felt their strength was at approximately 20%. Further, the worker noted that they were unaware of a pre-existing condition until the MRI was conducted. On May 22, 2020, Review Office requested the WCB medical advisor review the PPI examination regarding a possible cosmetic rating. The WCB medical advisor responded that the worker’s “ was undertaken arthroscopically and arthroscopic scans do not usually result in a ratable cosmetic PPI.”

On May 25, 2020, Review Office determined the worker’s PPI rating of 2.9% was incorrect and the correct rating was 2.89%. Review Office noted the criteria for the PPI rating was assessed accurately but noted the calculation for the loss of range of motion in the worker’s right shoulder was incorrectly calculated due to a rounding error and should rather be 2.89%. Review Office provided that while the calculation was incorrect, there would be no change to the monetary award provided to the worker as the award is payable for each full 1% rating and the worker received payment for a 2% rating. Accordingly, Review Office found that the award was not correct, but the monetary award paid to the worker was appropriate.

The worker filed an appeal with the Appeal Commission on July 28, 2020 and a file review was arranged for January 14, 2021.


Applicable Legislation and Policy

Under s 4(1) of the Act, where a worker suffers personal injury by accident arising out of and in the course of employment, compensation shall be paid to the worker by the WCB. That compensation includes awards for permanent partial impairment, as well as medical aid and wage loss benefits, as outlined in s 37 of the Act. Section 4(9) provides that the WCB may award compensation for an impairment that does not result in a loss of earning capacity, and s 38 of allows the WCB to determine the permanent partial impairment rating as a percentage of total body impairment and to make an award based upon each full percentage of whole body impairment.

The WCB’s Policy 44.90.10, Permanent Impairment Rating (the "Policy”) describes how permanent impairment ratings are calculated as a percentage of impairment as it relates to the whole body. The Policy provides that the degree of impairment will be established by the WCB's Healthcare Services Department in accordance with the Policy, and that whenever possible and reasonable, impairment ratings will be established strictly in accordance with the PPI Schedule which is attached as Schedule A to the Policy. The Policy confirms that the existence of a pre-existing condition will not negate an injured worker's entitlement to an impairment benefit arising from a compensable injury. If a worker has a pre-existing condition, the worker is eligible for an impairment rating based on the difference between the total rating and the rating assigned to the pre-existing condition. The WCB Healthcare Advisor will assign a fair rating to the pre-existing condition based on the best information available. When it is reasonable to do so, the assigned rating for the pre-existing condition will be based on the Schedules.

Schedule A to the Policy provides that permanent impairment from a workplace injury is evaluated for the following deficits:

• loss of a part of the body; 

• loss of mobility of a joint(s); 

• loss of function of any organ(s) of the body identified in the Schedule; and 

• cosmetic disfigurement of the body.

Determination of the rating for a pre-existing condition is also addressed in Schedule A. A pre-existing condition that is determined to be minor will be assigned a 0% impairment rating and a pre-existing condition that is determined to be major will be assigned an impairment rating equivalent to 50% of the impairment rating for that structure. A pre-existing condition is considered to be major for the purpose of the PPI determination if:

i. The impairment was/is significantly affected by the pre-existing condition; or 

ii. The diagnosis accepted by the WCB was adjudicated as an enhancement of a pre-existing condition; or 

iii. The diagnosis accepted by the WCB would not have occurred in the absence of the pre-existing condition.

Worker’s Position

The worker’s position is set out in the Appeal of Claims Decision form and his attached letter, received on November 23, 2020.

The worker appeals the WCB decision on the basis that the PPI rate calculation incorrectly took into account a pre-existing condition. The worker noted their belief that “...the pre-existing condition was not major because I had absolutely no symptoms. I was able to do my full duties without any issues before the accident.” The worker referenced the MRI study report from December 2017 and stated it did not indicate the degeneration and arthritis in the shoulder to be major, rather it showed it was minor.

The worker also disputes the WCB decision on the basis that the assessment for the PPI rating was “not fair or properly done. I was in the Doctor’s office for a total of 3 minutes....I would just like to have a proper and accurate assessment done so I can be properly paid.”

The worker noted that the injury has been life-changing, impacting their ability to play with grandchildren, to exercise and play golf and resulting in depression and anxiety. The worker’s position, in sum, is that the assessment was not fairly conducted, and the result improperly reduced due to a minor rather than major pre-existing condition.

Employer’s Position

The employer did not participate in the appeal.


The issue before the panel is whether the worker's permanent partial impairment rating was correctly determined. For the worker's appeal to succeed on this question, the panel must find that the Act or the Policy was not correctly applied. The panel was not able to make such a finding for the reasons that follow.

The panel considered whether the WCB medical advisor's assessment was conducted in accordance with the process set out in the Policy. The panel reviewed the assessment request of November 12, 2019 which set out the requirement for measurement of the worker’s active range of motion of both the left and right shoulders as well as recording of the scarring resulting from the arthroscopic surgery. The PPI assessment report dated February 28, 2020 notes that the evaluation took place over a period of 45 minutes on January 30, 2020 and that the worker consented to the assessment and accompanying interview. The report sets out, with respect to the surgical scarring that “There were four visible well-healed arthroscopy scars which were typical of what would be observed with this type of surgery. There was no evidence of keloid scarring or redness.” Active range of motion was tested on both shoulders.

The WCB medical advisor reviewed the PPI examination notes from January 30, 2020 and calculated the deficit in range of motion of the worker’s right shoulder as compared to the left shoulder, recording a difference of 135 degrees. This deficit was calculated by the WCB medical advisor to be equivalent to an impairment rating of 5.8%.

As noted by the Review Office, the calculation of the WCB medical advisor rounded the percentage of deficit range of motion from 23.07% to 23.1%, resulting in an impairment rating of 5.8% rather than 5.77%. We concur with the Review Office that the proper result of this step in the PPI calculation is 5.77% impairment.

The WCB medical advisor then went on to apply the Policy provisions with respect to a major pre-existing condition, reducing the impairment rating by 50% as set out in Schedule A to the Policy. The worker’s position is that the evidence does not support a finding that there was a “major” pre-existing condition such that the impairment rating should be reduced by 50% as required by Schedule A. The worker suggests that the fact the pre-existing condition was asymptomatic prior to the injury supports a conclusion that it was a minor condition, rather than major.

The panel considered the available medical evidence relating to the worker’s pre-existing right shoulder condition. A November 15, 2017 right shoulder x-ray revealed “mild sclerosis at the glenoid with no further acute or degenerative articular findings” and no “rotator cuff tendon calcification.” A December 2, 2017 MRI of the worker’s right shoulder revealed “significant glenohumeral joint osteoarthritic change with degenerative labral tearing.” A WCB medical advisor reviewed the MRI study findings on December 23, 2017 and concluded “There is noted degenerative changes that may delay recovery. There are degenerative changes to the rotator cuff, labrum and the glenohumeral joint....The noted degenerative changes may have been symptomatic in the past.”

The surgical report from October 1, 2018 outlined findings of arthritic changes throughout the glenohumeral joint, as well as fraying in the anterior labrum and inferior labrum. The surgeon summarized the findings as follows:

“....there were a number of different changes in the shoulder. Of significance, I think he had some anterior inferior instability. He has got associated arthritic change of the humeral head and periphery of the glenoid. He had associated anterior and superior labral damage. He did have some rotator cuff changes, but no full thickness tear.”

A WCB orthopedic advisor reviewed the file on December 6, 2018 and stated:

“It is probable that a labral tear and gleno-humeral osteoarthritis (OA) pre-existed the workplace injury of 24-Oct-2017 and were identified on MRI of 1-Dec-2017. It would take longer than 38 days for such pathology to develop. It is probable that the workplace injury made the instability of the shoulder joint worse, to a degree that labral repair became necessary. It is uncertain whether or not the workplace injury caused structural deterioration of the gleno-humeral OA. I consider that the increase shoulder joint instability over many months following the workplace injury would be expected, more likely than not, to cause an increased degree of OA. The partial thickness rotator cuff tear and tendinosis were probably pre-existing conditions and may or may not have been asymptomatic.”

The medical advisor went on to conclude that “...the workplace injury caused structural deterioration of the right glenoid labrum and increased gleno-humeral instability and increased gleno-humeral osteoarthritis.”

On April 4, 2019, the WCB orthopedic advisor stated that there was a pre-existing condition that significantly delayed recovery from the workplace injury. On November 12, 2019, a WCB medical advisor reviewed the worker’s file and stated that there is evidence of “...major pre-existing conditions” and that the worker’s mobility deficits are “a result of the CI [compensable injury] and the pre-existing conditions.”

On May 22, 2020, the WCB medical advisor confirmed to the Review Office that the worker’s surgery was undertaken arthroscopically, and that arthroscopic scars do not usually result in any ratable cosmetic impairment for PPI rating purposes.

On the basis of the medical opinions and clinical findings, the panel is satisfied that the Schedule A requirements for determining that a pre-existing condition is major have been met in that the worker’s permanent impairment is significantly affected by the pre-existing condition. Therefore, the panel concurs with the WCB determination that the worker’s impairment rating be reduced by 50% to reflect a major pre-existing condition.

The panel is satisfied, based on our review of the file, that the worker's 2020 PPI rating was determined in accordance with the provisions of the Policy. The panel therefore finds, on a balance of probabilities, that the worker's permanent partial impairment rating is correct.

The worker’s appeal is dismissed.

Panel Members

K. Dyck, Presiding Officer
J. MacKay, Commissioner
M. Kernaghan, Commissioner

Recording Secretary, J. Lee

K. Dyck - Presiding Officer
(on behalf of the panel)

Signed at Winnipeg this 27th day of January, 2021