The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

The worker is appealing the decision made by the Workers Compensation Board ("WCB") that they are not entitled to further benefits in relation to the June 24, 2019 accident. A videoconference hearing was held on April 27, 2021 to consider the worker's appeal.

Issue

Whether or not the worker is entitled to further benefits in relation to the June 24, 2019 accident.

Decision

The worker is entitled to further benefits in relation to the June 24, 2019 accident.

Background

The WCB received a Worker Incident Report on June 26, 2019, reporting the worker injured their neck, arms, buttock, back and possibly spine in an incident at work on June 24, 2019. The worker reported they were trying to de-escalate a volatile situation when they were assaulted by an individual. A Notice of Injury to Employer form completed on June 24, 2019 noted the worker sustained scratches on their arms and neck, torn muscles in their right hip, upper leg and buttocks. Further, it noted the worker had undergone a back surgery on November 15, 2018 and an x-ray indicated “…one of the titanium screws used in surgery had broken.”

The WCB received a Doctor’s First Report from the local emergency room for the worker’s attendance on June 24, 2019. The report indicated the worker’s report of pain to their right gluteal area, with back spasms and upon examination, the treating physician noted pain with palpitation and flexion of the worker’s right hip. The physician diagnosed back spasms, post assault and recommended modified, light duties. The worker was referred to their treating orthopedic surgeon. An x-ray of the worker’s lumbar spine taken the same date indicated “Internal fixation is again seen with pedicle screws at L3, L4 and L5. The right pedicle screw at L5 is fractured since February 26…”. On July 4, 2019, the WCB received information regarding the worker’s previous back surgery, including a discharge report from the surgery indicating the worker’s “…symptoms have greatly resolved…” and the worker was extremely happy with the results as well as two x-ray reports dated December 19, 2016 and February 26, 2019 that both noted normal results after the spinal fusion surgery.

On July 11, 2019, a WCB medical advisor reviewed the worker’s file. The advisor concluded the evidence supported a diagnosis of a soft tissue injury to the worker’s low back arising out of the workplace accident. With respect to the broken pedicle screw noted on x-ray, the WCB medical advisor commented that a review of medical literature indicated “…a fairly common occurrence of hardware failure/screw breakage within the first 6 months of surgery. This can occur in the absence of trauma. It is then unclear if the C/I (compensable injury) caused the screw to break or it occurred previously as a complication of the surgery and was only noted because the back was x-rayed.” The medical advisor recommended review of this issue after the worker saw the orthopedic surgeon.

The worker was assessed by the orthopedic surgeon on November 5, 2019. The surgeon noted the worker had undergone an L3 to L5 fusion surgery and had been experiencing “progressive mechanical pain” since the June 24, 2019 workplace accident. X-rays taken at the appointment noted fracture of the right-sided L5 pedicle screw as well as a left-sided L3 pedicle screw. Also noted was disc disease at L2-3 and L1-2. A further MRI study was recommended.

The MRI study of the worker’s lumbar spine was conducted on December 11, 2019 and the orthopedic surgeon opined the MRI confirmed “…significant stenosis above the previous surgery at L2-3. There is also mild stenosis residual at L3-4 in the level of the fixation.” The orthopedic surgeon recommended a revision surgery “…with placement of new screws as well as an extension of the fusion to the L2-3 level.”

Another WCB medical advisor reviewed a copy of the surgical report from the worker’s November 15, 2018 fusion surgery and on January 10, 2020 provided an opinion on the request for approval of the proposed surgery. The medical advisor indicated the worker’s current diagnosis was failed spinal stabilization/fusion fixation at L3-L5 with the worker’s initial diagnosis related to the workplace accident being a lumbar sprain/strain and buttock contusion. The advisor went on to opine “This soft tissue injury did not cause a fracture of the right L5 pedicle screw, nor the later fracture of the left L3 pedicle screw. These fractures were an indication of progressive failure of the surgical procedure of November 2018.” Accordingly, the WCB advised the orthopedic surgeon on January 10, 2020 that it would not accept financial responsibility for the proposed revision lumbar spine surgery and extension of fusion to L2-3. On February 14, 2020, the WCB advised the worker they were not entitled to further benefits as it had determined the current difficulties were not related to the June 24, 2019 workplace accident.

On September 4, 2020, the worker’s representative submitted further medical information, including an August 25, 2020 opinion letter from the orthopedic surgeon and a copy of the July 2, 2020 surgical report, requesting the WCB reconsider the February 14, 2020 decision. In the report, the surgeon indicated while it was difficult to prove the workplace accident resulted in broken pedicle screws, an x-ray taken in February 2019 prior to the workplace accident did not show a broken screw, whereas the x-ray taken directly after the accident did. A WCB medical advisor reviewed the new information from the worker’s representative and on September 14, 2020, confirmed the earlier opinion the worker’s current difficulties were a result of the failure of the previous surgery. On September 15, 2020, the WCB advised the worker’s representative there would be no change to the February 14, 2020 decision.

The worker’s representative requested reconsideration of the WCB’s decisions to Review Office on September 22, 2020. The representative presented the argument the worker’s ongoing difficulties and need for further surgery were at least partially related to the workplace accident and as such, the worker should be entitled to further benefits. On November 9, 2020, the employer provided a response in support of the WCB’s decision, a copy of which was provided to the worker’s representative.

Review Office determined, on November 19, 2020, the worker was not entitled to further benefits. Review Office noted the worker’s compensable injuries were consistent with a lumbar sprain/strain and a buttock contusion, with recovery within a short duration, and could not establish a more significant injury occurred as a result of the workplace accident. Review Office found the worker had a pre-existing condition in the form of the previous back surgery and degenerative disc disease, which was not caused or structurally changed by the June 24, 2019 workplace accident. Review Office could not relate the worker’s current difficulties to the workplace accident and determined the worker was not entitled to further benefits.

The worker’s representative filed an appeal with the Appeal Commission on November 19, 2020. A videoconference hearing was arranged and held on April 27, 2021.

Reasons

Applicable Legislation and Policy

The Appeal Commission and its panels are bound by the provisions of The Workers Compensation Act (the "Act"), regulations under that Act and the policies established by the WCB's Board of Directors.

A worker is entitled to benefits under s 4(1) of the Act when it is established that a worker has been injured as a result of an accident at work. Under s 4(2), a worker who is injured in an accident is entitled to wage loss benefits for the loss of earning capacity resulting from the accident, but no wage loss benefits are payable where the injury does not result in a loss of earning capacity during any period after the day on which the accident happens.

When the WCB determines that a worker has sustained a loss of earning capacity, an impairment or requires medical aid as a result of an accident, compensation is payable under s 37 of the Act. With regard to wage loss benefits, s 39(2) of the Act sets out that such benefits are payable until the worker's loss of earning capacity ends or the worker attains the age of 65 years.

Medical aid is provided for under s 27 of the Act which states that the WCB may provide a worker with such medical aid as the board considers necessary to cure and provide relief from an injury resulting from an accident.

The WCB's Board of Directors has established WCB Policy 44.10.20.10, Pre-existing Conditions (the "Policy"), which addresses eligibility for compensation in circumstances where a worker has a pre-existing condition. The purpose of the Policy is identified, in part, as follows:

The Workers Compensation Board (WCB) will not provide benefits for disablement resulting solely from the effects of a worker's pre-existing condition as a pre-existing condition is not "personal injury by accident arising out of and in the course of the employment." The WCB is only responsible for personal injury as a result of accidents that are determined to be arising out of and in the course of employment.

Worker’s Position

The worker was represented in the hearing by an advocate who made an oral submission on behalf of the worker and relied as well upon written submissions provided to the appeal panel and the employer in advance of the hearing date. The worker provided evidence in response to questions posed by the worker advisor and by members of the appeal panel.

The worker’s position, as outlined by the advocate, is that as a direct result of the compensable accident, the right-sided L5 pedicle screw was fractured, and that, subsequently, as a further consequence of the resulting spinal instability the left-sided L3 pedicle screw also fractured. The worker experienced continuing symptoms and required ongoing treatment including the July 2, 2020 surgery as a result of the accident. The spinal fusion hardware failures are the direct result of the workplace injury sustained on June 24, 2019 and therefore the worker should be entitled to benefits arising out of the surgical repair of that hardware.

The worker’s advocate noted that the worker was free of pain and fully functional prior to the June 24, 2019 workplace event. On that date, the worker was physically assaulted for approximately 12 minutes by a physically large individual trying to avoid detention, during which time the worker was repeatedly thrown against an automobile door such that the door was dented. The worker testified as to the details of the assault and noted that despite wearing some personal protective equipment, they suffered bruising and contusions, most evident in the areas of their body that did not have protection, including the lumbar spine area. Following the accident, the worker’s symptomatic presentation was markedly different than before and included intense pain in the worker’s low back region and difficulty with walking and bending. The worker indicated they returned to work on light duties after the accident but that symptoms continued and worsened over time.

The worker provided evidence to the panel of the active and physical nature of their job noting that prior to the accident, they were able to complete their duties without physical restriction. While the worker had a history of low back pain which they described as constant and progressive over the years and resulting in limitation of activities, following a period of recovery from the November 2018 surgical intervention, the worker was able to return to activities including walking and bicycling and returned to work without restriction early in 2019. The worker described that at the time of the February 2019 follow-up visit with the treating surgeon they felt fully recovered.

Following the July 2020 surgery, the worker described a slower recovery, noting they were off work for one month and then worked light duties until November 2020 at which time they returned to regular duties. The worker indicated that the recovery has not been as quick or as complete as after the first surgery.

The worker’s advocate outlined to the panel that while the WCB accepted that the compensable injury was a low back strain, there were two different medical issues identified by the diagnostic imaging and medical evidence: the progression of the worker’s pre-existing spinal stenosis, which is not related to the compensable injury; and the failure of the surgical hardware put in place in November 2018, which is related to the compensable injury. The advocate submitted that the panel should consider whether, but for the accident, the worker’s back condition would have deteriorated as it did and posited that there is no evidence to support that the surgical hardware had failed or was failing prior to the accident. Further, the advocate pointed to the WCB’s Pre-Existing Conditions Policy and suggested the evidence supports a finding that the worker’s pre-existing lower back condition was aggravated or enhanced as a result of the compensable workplace accident, and the resulting damage is therefore compensable.

In sum, the worker’s position is that as a result of the compensable accident, the right L5 screw was fractured, as identified in the x-ray taken on the date of the accident. Subsequently, as a result of the fractured screw, the worker experienced an increase in symptoms and the remaining intact fusion hardware began to fail in an environment where additional stress was placed upon it due to the fracture directly caused by the injury. As a result, the worker required further medical aid and experienced a loss of earning capacity. The worker should therefore be entitled to further benefits in relation to the June 24, 2019 accident.

Employer’s Position

The employer was represented in the hearing by its WCB coordinator who made an oral submission on behalf of the employer and answered questions posed by the panel.

The employer’s position is that as a result of the compensable workplace accident, the worker sustained a lumbar sprain/strain injury and that the issues relating to failure of the pre-existing lumbar spine fusion hardware are not the result of or related to the compensable injury. For this reason, the worker should not be entitled to further benefits in relation to the June 24, 2019 accident.

The employer’s advocate noted that there is no evidence that the broken screw identified in the June 24, 2019 x-ray was damaged as a result of the compensable workplace accident. The advocate relied upon the opinion of the WCB medical advisor of July 11, 2019 which sets out that the medical literature indicates screw failure is common within the first 6 months following a fusion surgery.

The employer’s advocate also noted that there was no other hardware failure or damage noted in the June 24, 2019 x-ray, although the MRI of December 11, 2019 revealed more damage. The employer’s position is that the imaging confirms this subsequent damage was not caused by or the result of the compensable workplace injury and further, that this subsequent hardware failure supports the position that the hardware failure is unrelated to the compensable injuries arising out of the June 24, 2019 assault of the worker.

The employer accepts the opinion of the WCB medical advisors that the compensable diagnosis is a lumbar sprain/strain injury, and that the workplace injury did not cause any fractures of the fusion hardware. Rather, the fusion hardware was in the process of a progressive failure of the initial surgical fusion procedure.

In sum, the employer’s position is that the decision of the Review Office was correct and should be upheld as the evidence does not support a finding that the failure of the hardware from the worker’s 2018 spinal stabilization surgery is related to or the result of the workplace accident. Rather this was the result of a progressive failure of the 2018 surgery. Therefore, the worker should not be entitled to further benefits in relation to the June 24, 2019 accident.

Analysis

The issue on appeal is whether or not the worker is entitled to further benefits in relation to the June 24, 2019 accident. In order to grant the worker’s appeal, the panel would have to find that as a result of the compensable injury, the worker continued to sustain a loss of earning capacity or to require medical aid to cure and provide relief from that injury. For the reasons outlined below, the panel was able to make such findings.

The panel considered whether the evidence supports that the spinal fusion hardware failed as a result of the trauma the worker sustained in the compensable accident. The evidence here is that the worker was seriously assaulted, causing significant trauma to the worker’s lumbar spine area, in particular, although more broadly as well. The panel found the worker to be a credible witness able to vividly describe how their injuries were sustained. The panel noted that the force applied to the worker’s body by the assailant was sufficient to cause damage to the passenger door of an automobile that the worker was thrown against.

There is no evidence that the worker experienced any ongoing limitations or symptoms arising from what was considered to be a successful surgical intervention for lower back concerns in late 2018; rather, the evidence supports that the worker had a full recovery and had regained functional capacity, returning to their full job duties within 3 months of the surgery. The worker noted that their job is active and often physical and that they were not having any difficulties with the job requirements in the months immediately prior to the workplace assault. The panel accepts the worker’s evidence as to their functional abilities at the time of the accident, and notes that this is further supported by the fact that the worker chose to interact with the individual who perpetrated the assault, despite being aware of that individual’s history of erratic and violent behaviour.

The evidence before the panel indicates that after the assault took place, the worker’s lower back again became symptomatic and despite the worker’s return to light duties, their back continued to deteriorate, becoming more painful over time, rather than less so as would be expected of a lower back sprain/strain injury as was diagnosed by the WCB medical advisor.

Further, the diagnostic imaging from the date of injury, revealed a broken titanium screw at the right L5. The most recent prior x-ray, taken in February 2019, showed all hardware to be intact. Later x-ray imaging, taken November 5, 2019 confirmed the fracture of the right L5 pedicle screw, as well as a fracture of the left L3 pedicle screw. The x-ray report of that date describes an impression of “progressive hardware failure”.

The panel considered the July 11, 2019 opinion of the WCB medical advisor who reviewed the worker’s file, that a review of medical literature indicates “…a fairly common occurrence of hardware failure/screw breakage within the first 6 months of surgery. This can occur in the absence of trauma. It is then unclear if the C/I (compensable injury) caused the screw to break or it occurred previously as a complication of the surgery and was only noted because the back was x-rayed.”

The panel also considered the opinion provided by the treating orthopedic surgeon, in a report to the worker’s advocate dated August 25, 2020. With respect to the cause of the broken L5 and later, L3 screws, the surgeon also indicates that determining causation is difficult, stating that:

“The question of the broken screws is indeed a very difficult one to prove OR disprove. In fact, there was an x-ray done as mentioned in February of 2019, prior to [the] assault, which was intact. The x-rays were done immediately the day of the assault and there was a broken screw. The fact that the patient was pain-free until the assault would in my opinion indicate that this was probably intact at the time of the assault.

The subsequent breakage of the other screws is probably related to the fact that there was such a lot of instability following the one broken screw.”

The panel also considered the September 11, 2020 opinion of the WCB medical advisor that:

“...based on the details of the prior surgical procedure using hinged pedicle screws that at best, would have achieved some stabilization of the disc levels involved, but not a fusion. This means that there remained a degree of intervertebral mobility at these levels resulting in stress forces on the screws, leading to loosening and fractures.”

The WCB medical advisor at the same time confirmed their January 8, 2020 opinion that the initial diagnosis of a lumbar sprain/strain and buttock contusion did not cause a fracture of the right L5 pedicle screw, nor the later fracture of the left L3 pedicle screw.

Based upon the totality of the evidence heard and reviewed, the panel finds that the diagnosis of lumbar sprain/strain and buttock contusion, accepted by the WCB as the compensable injury, does not fully encompass the extent of the injuries sustained by the worker in the assault that took place on June 24, 2019. The worker’s post-accident symptomatic presentation supports this conclusion, as the worker’s back symptoms in particular, did not resolve as would be expected of a sprain/strain injury, even considering the worker’s history of low back concerns, but worsened over time. This finding is supported by the opinion of the treating orthopedic surgeon.

The panel also finds that as a result of the workplace accident, the worker sustained damage to the spinal hardware that was put in place during the non-compensable surgery of November 2018. The panel accepts that the damage to the fusion hardware in place at the time of the injury, including both the fractures of the right L5 pedicle screw as well as the subsequent fracture of the left L3 pedicle screw, is a further result of and related to the compensable injury. We note that there are differing opinions provided by the WCB medical advisor and the treating orthopedic surgeon in this regard. While the treating orthopedic surgeon allows that determining causation is challenging in these circumstances, consistent with the views expressed by another WCB medical advisor on July 11, 2019, another medical advisor is definitive in their opinion that the screws could not have broken as a result of the compensable accident but were indicative of a failure of surgical hardware unrelated to the significant assault upon the worker. We agree that this is a question that cannot be definitively known in the absence of diagnostic imagery from immediately prior to the accident, but in the context of all the evidence before us, including the evidence of the worker as to the nature and extent of the assault and injuries as well as the medical evidence from before and after the injury, the panel is satisfied, on a balance of probabilities, that the hardware damage was sustained as a direct result of the workplace accident. Where the medical opinions diverge on the question of causation with respect to the damaged spinal hardware, the panel prefers and accepts the opinion of the treating orthopedic surgeon.

Therefore, the panel also accepts that the surgical intervention that took place in July 2020 to replace the loosened and damaged pedicle screws was related to the compensable injury, with the caveat that not all aspects of the surgery were related to the compensable injury.

The panel noted that the worker’s December 11, 2019 MRI revealed additional damage as well as spinal stenosis at L2-L3. The treating orthopedic surgeon stated that the L2-L3 level issues are “not really associated with the assault” and the WCB medical advisor agreed. The worker’s advocate confirmed this to be the worker’s position as well.

On the basis of the evidence and submissions, the panel finds that the issues at the L2-L3 level revealed by the December 2019 MRI and addressed in the July 2020 surgery did not arise out of the compensable accident but are a co-existing and non-compensable medical condition. Therefore, the panel determines that the aspects of this surgery related to the disc herniation and stenosis at L2-L3 are not related to the compensable workplace injury.

There is evidence before the panel that confirms that the worker was unable to return to work for a period of time following the July 2020 surgery and then returned to work on light duties until November 2020. On this basis, the panel finds, on a balance of probabilities, that the worker sustained a loss of earning capacity arising out of the compensable injury, related to the July 2020 surgery and recovery from that surgery, and further that the worker required medical aid to cure and provide relief from the compensable injury.

On the basis of the evidence considered and the findings noted, the panel determines that the worker is entitled to further benefits in relation to the June 24, 2019 accident. The worker’s appeal is allowed.

Panel Members

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

Recording Secretary, J. Lee

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

Signed at Winnipeg this 20th day of May, 2021