APPEALS RESOLUTION OFFICER DECISION
DECISION NUMBER:
20260020
OBJECTING PARTY:
worker
REPRESENTED by:
worker REPRESENTATIVE
RESPONDENT PARTY:
employer
REPRESENTED by:
employER REPRESENTATIVE
HEARING:
HEARING IN WRITING
HEARD by:
Brian Smith, appeals resolution officer
January 7, 2026
ISSUE
The worker objects to the Case Manager’s March 29, 2023 decision that denied entitlement to ongoing benefits for a right hip injury.
BACKGROUND
The history and nature of the claim are well documented in the prior Appeal Resolution Officer (ARO) decisions dated November 3, 2022 and March 29, 2023. Therefore, I will not repeat it in its entirety.
Briefly, on December 27, 2020, this Associate reported to their employer that they were feeling pain in their left ankle and left knee. The worker attributed the pain to operating an order picker vehicle, specifically from having to place their left foot on the vehicle’s Deadman pedal for prolonged periods.
After initially denying the claim in March 2021, the claim was reconsidered in April 2021 and allowed for left foot tendonitis and loss of earnings benefits from April 18, 2021 to June 18, 2021.
On September 24, 2021, a Case Manager allowed entitlement to healthcare benefits for a low back
strain/sprain, which resulted from the altered gait created by the left foot injury. In the same decision, entitlement to a magnetic resonance imaging scan (MRI) for the low back to rule out a disc herniation was denied, entitlement to healthcare benefits for a right femoroacetabular impingement and a subclinical bilateral slipped capital femoral epiphysis (SCFE) were denied, and it was concluded that the worker had reached maximum medical recovery (MMR) with no permanent impairment as of September 16, 2021. The worker objected.
On November 3, 2022, an ARO reviewed the September 24, 2021 decision and concluded the following:
The worker has ongoing entitlement to benefits for their left foot beyond September 16, 2021. The worker achieved MMR with a permanent impairment on November 29, 2021 and is entitled to a non-economic loss assessment for their left foot.
The worker has entitlement for a right hip injury as a Secondary Condition resulting from the worker’s left foot injury
The worker has entitlement to health care benefits for a right hip injury, including any diagnostic scans that serve to clarify the diagnosis that were recommended by a health professional at least during the period of my review (to September 24, 2021).
The worker is entitled to Return-to-Work (RTW) Services.
The worker does not have ongoing entitlement for a back injury beyond September 16, 2021.
On March 29, 2023, a Case Manager completed their implementation of the November 3, 2022, ARO decision. The Case Manager noted that the claim had been referred for a NEL assessment. They concluded that entitlement to benefits for the diagnosed right femoral acetabular impingement and labral tear was not in order.
The Case Manager also determined the worker sustained a sprain/strain injury as a secondary condition, that resolved by September 16, 2021, therefore, there was no entitlement of further health care for the hip. The worker was also partially impaired, able to partially mitigate their wage loss and is entitled to partial loss of earnings from February 23, 2022 to March 29, 2023, based on the ability to earn $15.00 per hour for 40 hours per week.
The worker objected to the denial of entitlement to benefits for the diagnosed right femoral acetabular impingement and labral tear in the March 29, 2023 decision. The decision was reconsidered and remained unchanged. As a result, the claim has been referred to the Appeals Services Division for further review.
AUTHORITY
Operational Policy Manual
Published
15-05-01 Resulting from Work-Related Disability/Impairment 15-02-03 Pre-existing Conditions
April 9, 2021 November 3, 2014
ANALYSIS
I have carefully considered all the available information, legislation and relevant operational policies in reaching this decision. I find worker is entitled to ongoing benefits for their right hip femoroacetabular impingement as their underlying hip condition was exacerbated by the compensable injury. My reason and analysis follow.
The worker contends that entitlement to benefits for ongoing hip issues ought to be in order. They submit that prior to the workplace accident the worker was asymptomatic and free of any back or hip issues. They also contend that the available medical information supports a causal link between the workplace injury and the diagnosed labral tear. Consequently, the worker is entitled to recognition of a permanent impairment and ongoing benefits.
The employer contends that the Case Manager’s decision is correct. They submit that the diagnosed conditions for which the worker is requesting entitlement developed during childhood or adolescence.
and are not related to the workplace accident and entitlement to a rip hip injury should not have been allowed at all. Consequently, the worker’s appeal should be denied.
In reaching a decision, I have relied on policy 15-05-01 Resulting from Work-Related Disability/Impairment that says workers sustaining secondary conditions that are causally linked to the work-related injury will derive benefits to compensate for the further aggravation of the work-related impairment or for new injuries.
I have also considered policy 15-02-03 Pre-existing Conditions that says entitlement for a work-related injury/disease will not be denied due to the existence of a pre-existing condition. Once initial entitlement is established, the decision-maker considers the impact, if any, of pre-existing conditions on the worker’s ongoing impairment.
In their November 3, 2022 decision, the ARO found that the accident history, including the period from December 2020 to February 2021, is compatible with the development and ongoing exacerbation of injuries in the worker’s left foot, low back, and right hip.
The ARO remitted the benefits flowing to operations and granted entitlement to diagnostic scans to clarify the diagnosis. In the implementation of the ARO decision, the worker underwent an MRI in December 2021. The MRI revealed a CAM type femoral head and labral tear.
With respect to the worker’s right hip, I note that the Case Manager concluded that the worker was being treated for a congenital condition, which therefore meant it was not caused by the altered gait due to the foot injury and because the ARO has accepted entitlement for a right hip injury without providing a specific diagnosis, the Case Manager concluded that the worker sustained a sprain/strain injury as a secondary condition that also resolved by September 16, 2021.
In my review of the available medical information, I see that Dr. Feibel, Orthopaedic Surgeon, conducted a lower extremity assessment on August 27, 2021, and noted the right femoroacetabular impingement as an occupational diagnosis, he did not diagnose a sprain/strain.
It is my understanding that femoroacetabular impingement is associated with unusually shaped joints of the femoral head or the acetabulum cup that cause bones to rub, damaging cartilage and the labrum and anyone can be born with or develop hip impingement, and that the CAM type femoral head is one type of abnormality in the hip that can cause a labral tear.
However, I find that I cannot ignore that the worker had no issues prior to the December 27, 2020 workplace accident. In that regard, policy 15-02-03 recognizes that the “thin skull” and “crumbling skull” doctrines are well-established legal principles that are components of decision-making at the WSIB.
The essence of the “thin skull” doctrine is that entitlement to benefits is not reduced due to a pre-existing condition that made the worker more vulnerable to injury, in cases where the workplace accident has made a significant contribution to the resulting injury. The “crumbling skull” doctrine, however, deals with a worker who has a much more unstable pre-existing condition which was likely symptomatic and would have eventually required some degree of intervention.
While I acknowledge the impingement was caused by the worker hip abnormality, I am not led to conclude that the worker’s underlying condition falls within the scope of the “crumbling skull” doctrine. In my view the weight of the evidence before me indicates that the worker’s pre-existing condition contributed to the worker’s overall impairment in terms of its severity. I find that the worker’s pre-existing condition fits the “thin skull” doctrine, in that they had an asymptomatic condition that predisposed them to far greater impairment from the workplace accident than would have been the case if they did not have those findings.
As a result, I have placed weight on the opinion provided at the lower extremity assessment that the impingement is occupationally related. I am also unable to accept that it is simply a coincidence that the worker’s underlying hip issue became an issue around the same time that they suffered a workplace accident that led to a limp that led to an accepted secondary injury to the worker’s low back and hip.
In my view, the worker’s hip becoming symptomatic shortly after the worker’s gait was altered by the compensable injury, supports a causal relationship between the work-related injury and the diagnosed femoroacetabular impingement. Accordingly, I find that the worker’s asymptomatic condition was exacerbated by this relationship and entitlement to an ongoing hip impairment beyond August 18, 2022 is in order.
CONCLUSION
The worker’s objection is allowed.
The worker is entitled to ongoing benefits for their right hip femoroacetabular impingement as their underlying hip condition was exacerbated by the compensable injury. The benefits flowing from this decision is remitted to the operating area for further adjudication.
DATED January 7, 2026
Brian Smith
Appeals Resolution Officer
Appeals Services Division