Frenette v. Workplace Health, Safety and Compensation Commission

Executive Summary: Key Legal and Evidentiary Issues

• Causation dispute over whether a 2019 lumbar laminectomy and fusion was reasonably related to a 2000 compensable thoracic back injury.
• Competing medical opinions on whether pre-existing spondylolysis and later spondylolisthesis at L5-S1 were aggravated by the workplace accident or simply followed their natural degenerative progression.
• Application of s. 7(5) of the Workers’ Compensation Act and Policy 21-101 on pre-existing conditions, which distinguish compensable aggravation from non-compensable natural progression of disease.
• Assessment of medical evidence under Policy 21-113 on decision-making, including weighing expertise, objectivity, chronology, and consistency of medical reports.
• Deference to the Appeals Tribunal’s factual findings under the “palpable and overriding error” standard of review in workers’ compensation appeals.
• Ultimate finding that the evidence did not establish a reasonable causal link between the 2000 thoracic injury and the later lumbar pathology requiring surgery, resulting in dismissal of the worker’s appeal with no costs and no monetary award.

Background and facts of the workplace injury

On September 29, 2000, Michel Frenette was working as a welder in Saint John when he injured his back pulling on cables. He experienced a sharp pain and had difficulty breathing for about ten minutes, and the incident was reported to his employer. He was placed on medical leave by his physician, Dr. Robert White, and filed a workers’ compensation claim with the Workplace Health, Safety and Compensation Commission. The claim described an injury to the upper back and was accepted for an upper thoracic strain, a soft-tissue/myofascial injury in the mid-back region. As a result, Mr. Frenette received long-term benefits. Over many years, the medical documentation consistently characterized his accepted compensable condition as a thoracic myofascial injury with pain that radiated toward the upper and lower back and into the anterior chest wall. Various reports from chiropractors and physicians, including substantial reporting by chiropractor Michel Blanchette, focused almost entirely on thoracic spine symptoms. A few early notes mentioned low-back discomfort, but the predominant and documented focus remained the thoracic area. Periodic imaging was ordered in the years after the accident, but only of the thoracic region, at least up to 2014.

Emergence of lumbar problems and proposed surgery

In September 2016, Mr. Frenette developed significant pain in his right hip and lumbar (low-back) region. His new family physician, Dr. Jean-Pierre Arseneau, ordered an X-ray of the hip and referred him to orthopedic surgeon Dr. Marc-André LeBlanc, a specialist in hip and knee replacement. Dr. LeBlanc arranged for an MRI, performed on March 8, 2018, which demonstrated bilateral spondylolysis at L5, with grade I spondylolisthesis at L5-S1 and moderate degenerative disc disease at that level. On reviewing the MRI, Dr. LeBlanc concluded that he could not proceed with hip replacement until the lumbar spine problem was addressed. He referred Mr. Frenette to Dr. Michel-Alexandre LeBreton, an orthopedic surgeon specializing in spinal surgery. Dr. LeBreton recommended a laminectomy and lumbar fusion at L5-S1 to address the spondylolisthesis and associated foraminal stenosis. Mr. Frenette promptly informed the Commission, which indicated that an internal medical assessment would be conducted to decide whether the proposed spinal surgery was reasonably related to his accepted workplace injury. In a July 31, 2018 progress report, Dr. Arseneau recorded low-back pain and noted that Mr. Frenette’s symptoms were progressing slowly but steadily. On January 23, 2019, Dr. Rachel Fox, a medical advisor for the Commission, prepared an internal report concluding that the MRI-documented L5-S1 spondylolisthesis and foraminal stenosis, secondary to degenerative changes, were not reasonably related to the claim for thoracic strain and myofascial pain in the thoracic spine. She therefore advised that the planned L5-S1 laminectomy and fusion were not reasonably related to the accepted claim. Relying on this advice, the Commission wrote to Mr. Frenette on February 13, 2019, refusing to fund the February 15, 2019 lumbar surgery under his 2000 claim. The letter emphasized that his claim had been accepted for thoracic myofascial pain with chronic radiation into cervical and lumbar areas, but with no neurological deficits, and that the degenerative L5-S1 changes identified on MRI were not reasonably related to that thoracic strain.

Medical evidence on pre-existing lumbar degeneration

Following the refusal, an appeal was filed, though Mr. Frenette’s workers’ advocate asked that the hearing be delayed until he was physically able to participate. On July 15, 2019, the advocate wrote to Dr. LeBreton, summarizing the case, posing specific causation questions and providing space for his answers. When asked whether there was a causal link between the compensable injury and the grade I isthmic spondylolisthesis at L5-S1 causing foraminal stenosis, Dr. LeBreton did not choose a simple “yes” or “no.” Instead, he referred to imaging as follows: an August 25, 2014 imaging study that raised suspicion of L5 spondylolysis without listhesis, and the March 8, 2018 MRI showing grade I L5-S1 spondylolisthesis. As there had been no earlier imaging, he concluded that the condition had progressed and opined that the spondylolysis was most likely present before the 2000 workplace accident. The advocate also asked him to comment on the Commission’s assertion that the L5-S1 spondylolisthesis and foraminal stenosis were not reasonably related to the accepted thoracic strain/myofascial condition. Dr. LeBreton disagreed in part, explaining that the initial pain “may” have been secondary to pain arising from the L5 lysis. He described spondylolysis as akin to a fracture of the pars interarticularis that does not heal, leaving fibrous tissue at the cortical break that can be affected by trauma. However, he stressed that the progression to grade I spondylolisthesis took approximately 16–18 years after the injury, indicating a slow, degenerative development rather than an immediate traumatic effect. On a further question about whether the degenerative changes were related to the compensable injury, he added a “maybe” option and indicated that, in his opinion, the L5 lysis pre-dated the workplace accident, although the trauma might have caused the initial lumbar pain and a person with spondylolysis could be more susceptible to a lumbar injury. Separately, in a disability tax credit certificate dated May 28, 2021, Dr. Arseneau described Mr. Frenette as having a lumbar problem with vertebral fusion and several injuries related to his work affecting both the thoracic and lumbar spine, as well as coxarthrosis. He noted that Mr. Frenette limped constantly, had difficulty walking, used a cane most of the time, needed help dressing, had been severely impaired for about three years, and was no longer able to work.

Workers’ Compensation Appeals Tribunal’s decision

The Workers’ Compensation Appeals Tribunal heard the appeal on October 21, 2024, with Mr. Frenette represented by counsel, and issued its decision on January 15, 2025. The Tribunal reviewed the history of the claim, Mr. Frenette’s evidence, the extensive medical record and the parties’ submissions. It identified the governing statutory framework in s. 7 of the Workers’ Compensation Act (WCA), including s. 7(1) (general entitlement where an accident arising out of and in the course of employment causes personal injury) and s. 7(5), which addresses situations where a work-related personal injury exacerbates or aggravates a pre-existing disease or condition. Under s. 7(5), compensation is only payable for what is reasonably attributable to the injury caused by the accident, and not for the natural progression of the pre-existing condition. The Tribunal also applied WorkSafeNB Policy 21-101 on Pre-existing Conditions, which requires the decision-maker to gather and weigh medical evidence to determine whether there is a reasonable medical probability that an accident-related injury exacerbated or aggravated a pre-existing condition. Where that probability is supported, medical aid and benefits may be paid both for the accident-related injury and for the exacerbation. However, the policy is explicit that WorkSafeNB does not pay for treatment or benefits based solely on the natural progression of a pre-existing condition, nor when there is no link between the work injury and the underlying disease. In addition, the Tribunal relied on Policy 21-113 on Decision-making, which sets out the standard of proof and method for weighing evidence. It confirms that workers’ compensation decisions must be based on a “preponderance of evidence” standard—whether a fact is more likely than not—and requires evaluators to consider the relevance and reliability of the evidence, the expertise of the medical professionals, the objectivity of the data, and the timing of reported symptoms and findings. Applying these principles, the Tribunal reviewed the medical reports referring to low-back pain and lumbar findings. It noted that the chiropractor’s 2002 report mentioning degenerative changes in the lumbar spine did not address the impact of the 2000 accident on those changes. It also found that Dr. Arseneau’s opinion—that the workplace accident affected the degenerative condition—was not grounded in objective evidence. The Tribunal preferred the evidence of orthopedic spine surgeon Dr. LeBreton, given his specialized expertise, his role as the surgeon who performed the 2019 operation, and his direct review and interpretation of the imaging. It accepted that, at most, his evidence suggested that the 2000 accident could possibly have affected the degenerative condition, but that he was careful not to draw a direct causal link. It also adopted his view, supported by other documentation, that the condition progressed slowly over many years. On this basis, the Tribunal concluded that the 2019 lumbar surgery, which occurred almost 19 years after the accident, was required as a result of the natural progression of a pre-existing degenerative lumbar condition, not as a consequence of the original workplace accident. As the worker’s claim had been accepted for a thoracic and cervical injury—not a lumbar injury—and the evidence did not establish a compensable aggravation of any pre-existing lumbar disease, the Tribunal found that the statutory requirements of s. 7(5) were not met and dismissed the appeal.

Appeal to the New Brunswick Court of Appeal and standard of review

Mr. Frenette appealed the Tribunal’s decision to the New Brunswick Court of Appeal. Acting initially on his own, he filed a notice of appeal that raised three grounds, two of which were withdrawn at the start of the hearing. With counsel, he ultimately pursued a single ground: that the Tribunal had failed to follow the decision-making policy, in particular Policy 21-113, and had drawn an “impossible inference” when it said that Dr. LeBreton was careful not to make a direct link between the September 2000 injury and the later lumbar symptoms requiring surgery. The Court of Appeal framed the applicable standard of review by reference to the Workplace Health, Safety and Compensation Commission and Workers’ Compensation Appeals Tribunal Act. Section 21(12) provides a right of appeal to the Court of Appeal on questions of jurisdiction or law, while s. 21(9) requires the Appeals Tribunal to decide each case on its real merits and justice. Building on its earlier decision in Longphee v. Workplace Health, Safety and Compensation Commission, the Court reiterated that questions of law and jurisdiction are reviewed for correctness, while questions of fact—or mixed fact and law where no clear legal question can be extracted—are reviewed only for palpable and overriding error. This deferential standard protects the Tribunal’s role as primary finder of fact, especially in specialized areas such as workers’ compensation, where tribunals routinely weigh complex medical evidence.

Application of policies on pre-existing conditions and weighing of medical evidence

The Court then revisited the statutory and policy framework. It confirmed the operation of s. 7(5) WCA, which allows compensation where a work-related injury aggravates a pre-existing condition, but expressly excludes compensation for the natural progression of that condition. It also acknowledged the binding role of Policy 21-101, which reflects the same distinction, and Policy 21-113, which requires decisions to rest on a preponderance of the evidence and sets out specific criteria for assessing conflicting medical opinions. Against this framework, the Court considered the attack on the Tribunal’s reading of Dr. LeBreton’s evidence. Mr. Frenette argued that the Tribunal mischaracterized that evidence by saying the surgeon was careful not to establish a direct causal link, thereby misapplying the preponderance standard. The Court disagreed. It noted that Dr. LeBreton had deliberately declined to give a simple “yes/no” answer to the main causation question, had introduced a “maybe” option, and had provided clarifications that raised significant doubt about a direct causal link between the 2000 thoracic injury and the later lumbar degenerative pathology. In light of those qualifications, the Tribunal was entitled to find that the surgeon had been cautious not to state a direct causal relationship. The Court found no palpable and overriding error in that reading of the evidence. The Court also reviewed the broader evidentiary record, which showed that the 2000 injury was accepted as thoracic in nature and that medical records for many years focused almost entirely on thoracic pain radiating into other regions. The more than sixty reports from chiropractor Dr. Blanchette, and numerous follow-up reports from Dr. White, largely confined the focus to the thoracic spine, with only occasional notations of low-back symptoms. Imaging until 2014 was directed to the thoracic area. It was only from 2016 onward that the file reflected significant lumbar pain and right-hip issues, leading to the investigations that uncovered the L5-S1 spondylolisthesis. Crucially, Dr. LeBreton’s opinion was that spondylolysis at L5 was most likely present before the workplace accident and that the actual displacement of the vertebra (spondylolisthesis) and resulting stenosis emerged sometime between the 2014 and 2018 imaging, long after the 2000 injury. Although he acknowledged that trauma might have triggered initial lumbar pain in someone with pre-existing spondylolysis, he emphasized the slow 16- to 18-year progression to spondylolisthesis, which strongly suggested a degenerative course rather than a direct traumatic effect of the 2000 incident.

Outcome of the appeal and treatment of costs and monetary relief

On this record, the Court of Appeal concluded that the Tribunal had properly considered all the evidence, correctly applied the Workers’ Compensation Act and the applicable policies, and reasonably preferred the specialized evidence of the spinal surgeon over the more general opinions of the chiropractor and family physician. It accepted the Tribunal’s factual findings that the 2000 accident caused a thoracic, not a lumbar, injury; that the degenerative lumbar changes developed gradually many years later; and that the 2019 lumbar surgery was required because of the natural progression of a pre-existing degenerative condition rather than because of a compensable aggravation by the 2000 accident. These were findings of fact, supported by the evidentiary record, and they did not disclose any palpable and overriding error or a misapplication of the preponderance-of-evidence standard. Accordingly, the Court dismissed Mr. Frenette’s appeal. Consistent with the Court’s long-standing practice in workers’ compensation matters, it did not award costs. There is no indication in the judgment of any monetary award, damages, or reimbursement being ordered in favour of either party. The successful party in the appeal is the Workplace Health, Safety and Compensation Commission, and the total monetary amount ordered in its favour—whether as costs, damages, or any other financial relief—cannot be determined from the decision and appears to be nil, as the appeal was simply dismissed without costs and without any new monetary orders.