Decision #14/10 - Type: Workers Compensation
Preamble
On November 10, 2006, the worker injured his low back during the course of his employment. The claim for compensation was accepted by the Workers Compensation Board (“WCB”) and benefits were paid to the worker to May 16, 2008, when it was determined that he had recovered from the effects of his compensable injury. The worker disagreed with the decision and an appeal was filed with the Appeal Commission through the Worker Advisor Office. A hearing was held on December 15, 2009 to consider the matter.
Issue
Whether or not wage loss benefits are payable beyond May 16, 2008.
Decision
That wage loss benefits are payable from May 16, 2008 to June 23, 2009.
Decision: Unanimous
Background
The worker reported that he injured his low back on November 10, 2006 when loading empty oxygen tanks, weighing from 10 to 68 kilograms each, into his vehicle. He had a back spasm in his lower back and was unable to lift any weight or walk without great pain.
He immediately attended upon his family physician and X-rays of the lumbar spine taken the day of the accident revealed grade 1 spondylolisthesis of L5 on S1. It was reported that the condition may be related to facet arthropathy; however, a defect could not be excluded. There was disc space narrowing at the L4-L5 level with severe changes at L5-S1. He was prescribed anti-inflammatories and was advised not to work for at least one week.
A doctor’s first report dated November 14, 2006 indicated that the worker had tenderness in the right upper buttock and SI joint. It was noted that the worker had no problems with his back prior to the accident. A diagnosis of back strain was made and physiotherapy treatment was arranged. The claim for compensation was accepted and benefits were paid to the worker.
The initial physiotherapy assessment dated November 24, 2006 noted pain radiation into the posterior right thigh and calf.
A December 16, 2006 CT Scan noted mild disc bulging, facet arthropathy and mild spinal stenosis at L2-L3, degenerative disc, facet arthropathy and mild stenosis at L3-L4, moderate spinal stenosis at L4-L5, and significant degenerative disc disease, facet arthropathy and mild spinal stenosis at L5-S1.
On December 27, 2006, a WCB medical advisor outlined her opinion that based on the mechanism of injury, the diagnosis was an aggravation of degenerative lumbar disease. She expected that the aggravation would resolve within 4 to 10 weeks but noted that could be variable. Work restrictions were outlined to avoid lifting over 10 pounds, repetitive twisting and bending and sustained flexion.
In a physiotherapy report dated January 26, 2007, it was reported that the worker was discharged from treatment due to a lack of improvement in his back condition.
At the request of his treating physician, the worker was referred to a neurologist. In a report dated March 23, 2007, the neurologist reported that the worker’s presentation was suggestive of predominantly musculoskeletal lumbar pain from the moderately significant spondylotic changes. “He may well have some intermittent right L5 root irritation, without any evidence of significant radicular/neuropathic dysfunction otherwise. He likely had some acute spondylotic changes superimposed on chronic disease”. The neurologist saw no need for further neurologic investigations.
A WCB medical advisor reviewed the file on March 28, 2007 and confirmed a diagnosis of mechanical back pain secondary to degenerative disease of the lumbar spine. He noted that “all symptoms may relate to PreX”. Restrictions of limited sedentary work and no lifting or bending were put in place.
File records showed that the worker was seen by a physical medicine and rehabilitation specialist (physiatrist) on August 30, 2007 for low back pain with intermittent radiation to both legs. He noted that imaging studies demonstrated significant degenerative changes in the lumbosacral spine. There was evidence of possible nerve root compression and mild spinal stenosis as well as osteoarthritic degeneration of the facet joints. Neurological examination was considered to be completely normal. The specialist referred the worker to another physiatrist for possible epidural steroid injections/facet joint injections.
In a review by the WCB medical advisor on September 17, 2007 it was noted that the worker had degenerative disc disease with spinal stenosis. The aggravation of the pre existing condition was not considered to be resolved. Restrictions of no repeated bending, stooping or crouching and no repeated weights above fifteen pounds were noted.
In a report dated February 8, 2008, the second physiatrist stated:
“The range of motion of the lumbar spine is within normal limits in all directions and pain free. There is full reversal of the lumbar lordosis . . . .
His CT scan of December 15, 2006, shows widespread degenerative changes. These appear to be maximal of L4-5, where moderate central and foraminal stenosis are seen.
In summary, this patient has symptoms of right L5 radicular pain with no clinical signs. This correlates moderately well with his previous CT scan.”
The physiatrist recommended an epidural injection to treat the worker’s radicular pain; however, there was a possible conflict with treatment for an unrelated medical condition.
On February 21, 2008, a WCB medical advisor concluded that based on the February 8, 2008 report, the worker had recovered from his compensable injury. He noted that the physiatrist was recommending an epidural injection and that, “We should follow carefully.”
In a decision dated May 9, 2008, the worker was advised that in the opinion of the WCB, he had recovered from his work injury and that his current disability was the result of an underlying or pre-existing condition, the progression of which was not enhanced or accelerated by the work related accident. The worker was advised that wage loss benefits would be paid to May 16, 2008 inclusive.
In a report to the WCB dated May 23, 2008, the second physiatrist stated:
“When a spinal nerve is compromised, oftentimes the affected patient presents with pain in the distribution of the spinal nerve, in addition to objective signs of spinal nerve dysfunction such as motor, sensory or reflex changes. However, there is a broad spectrum of clinical presentations with a percentage of patients presenting with symptoms without medically objectifiable physical signs. As such, I would not agree that this patient has recovered from his condition (as of February 8, 2008). Whether this condition is considered compensable, it is a matter for WCB to determine.”
The physiatrist noted that an epidural injection to treat the radicular pain was contraindicated given his ongoing treatment for the unrelated medical condition.
On June 11, 2008, a WCB medical advisor confirmed that in his opinion, the worker had recovered from the effects of his compensable injury and that the aggravation of his pre-existing condition had resolved. He noted that the worker had a number of non-compensable physical issues which may contribute to his symptomatology.
In a decision dated June 17, 2008, the worker was advised that the May 9, 2008 decision was confirmed. The case manager indicated that the worker’s ongoing difficulties were non compensable.
On July 24, 2008, the referring physiatrist indicated that he last saw the worker on June 16, 2008, and that he continued to have right sided low back pain radiating to the right leg. He expressed the opinion that the worker’s symptomatology was partly secondary to his work related injury, and that it was “quite possible that his injury exacerbated already present degenerative changes in his lumbosacral spine and facilitated pain as well as create[d] a new pain sensation arising from nerve root irritation”. He also noted that the second physiatrist had observed that the worker’s symptoms correlated moderately well with the previous CT scan.
In September 2008, primary adjudication referred the file to a WCB physiatry consultant to review the recent medical information and to comment on the worker’s status. In a response dated September 12, 2008, the consultant stated:
“On file review, the original reported incident occurred in 2006 now approaching 2 years ago. The physiotherapist felt a muscle strain had likely occurred. The neurologist concurred with no evidence of any neurological involvement. The CT scan of the lumbar spine notes severe preexisting changes. There was no evidence of any persisting physical diagnosis or injury component and on a balance of probabilities the prior muscle strain has resolved.”
He also expressed the opinion that the aggravation of the pre-existing condition had resolved.
On September 15, 2008, the worker was advised by his case manager that she was unable to rescind the original decision of May 9, 2008. The case manager indicated that the worker’s ongoing difficulties were not compensable as they were a result of a pre-existing condition, which had not been accelerated or enhanced as a result of the compensable injury.
On October 1, 2008 the referring physiatrist reported that the workplace injury had caused an aggravation of the worker’s pre-existing conditions, although he was unable to confirm an enhancement given the worker’s unrelated conditions. He outlined permanent restrictions of no repetitive lifting and a maximum load of 15 pounds.
On October 17, 2008, a worker advisor appealed the case manager’s decision to Review Office on the worker’s behalf. The worker advisor submitted that the worker had not fully recovered from his compensable injury and could not return to his pre-accident employment. He attributed the worker’s ongoing symptoms and restrictions to the combined effect of his injury and pre-existing conditions.
On November 6, 2008, Review Office determined that wage loss benefits were not payable beyond May 16, 2008. In its decision, Review Office noted that on July 3, 2007, eleven months prior to the termination of benefits by the WCB, the worker advised a case manager that his low back pain was not constant, and only caused great difficulty with activity. It otherwise did not bother him too much. Review Office also noted the physiatrist’s report of February 8, 2008 in which he indicated that the worker had other non-compensable conditions which would likely compound the clinical presentation.
Review Office concluded that any ongoing signs and symptoms were likely related to something other than the strain occurring on November 10, 2006. Two WCB consultants had each indicated that on a balance of probabilities, the aggravation of the underlying pre-existing conditions in the worker’s low back had resolved and that any ongoing symptoms did not have a relationship to the original strain-type injury occurring in November 2006. The worker had received WCB coverage on his claim for one and a half years and Review Office found that this was a significant amount of time to allow for physical rehabilitation of the compensable aggravation of the underlying pre-existing conditions.
On January 2, 2009 the worker advisor requested reconsideration of Review Office’s decision based on new medical evidence provided by the referring physiatrist. The worker advisor submitted that it supported the conclusion that the workplace accident had caused a permanent worsening of the worker’s pre-existing non-compensable conditions. In a report dated January 6, 2009 the physiatrist stated:
“…the pain generators are:
a) facet arthropathy
b) degenerative disc disease
c) nerve root compression.
Facet arthropathy and degenerative disc disease are, in my opinion, non-compensable (pre-existing conditions). Nerve root compression is a compensable injury. The work related injury changed the anatomic position of the disc, and nerve irritation is a consequence. Movement of the disc can cause additional change/damage to pre-existing conditions architectonics, causing aggravation in symptomatology even if the client is off work. In addition, in my opinion the compensable injury (nerve root compression) permanently and adversely affects pre-existing conditions mentioned under a) and b). Compounding variables mentioned in my previous reports do not have a significant role since there was no clinical evidence of neither intermittent claudication nor diabetic neuropathy at the last two office visits. At the same time, his back pain has remained unchanged.”
Review Office responded on January 29, 2009, that after reviewing the new medical evidence, the rationale provided in its earlier November 6, 2008 decision to terminate WCB responsibility still applied and that no change would be made to the decision. Review Office stated that any opinion that the strain injury of November 10, 2006 enhanced the severe underlying pre-existing conditions was speculative in nature, as WCB physicians had indicated that there was no objective evidence on file that such a scenario had occurred.
On July 23, 2009, the worker advisor appealed Review Office’s decision to the Appeal Commission and a hearing was arranged.
Prior to the hearing, the worker advisor submitted additional medical information updating the worker’s condition and treatment. A consulting physiatrist had recommended a second attempt at epidural cortisone injection, given the worker’s ongoing pain, which appeared to be radicular in nature. A CT scan conducted on June 10, 2009 noted osteoarthritic changes at L3-L4 and L4-L5, with posterior displacement (as well as probable irritation) of the descending right L5 nerve root. The worker subsequently underwent a right L5 – S1 transforaminal epidural injection and reported immediate relief of pain. When seen on June 23, 2009 the treating physiatrist noted that the worker had responded both diagnostically and therapeutically and that the injection had provided sustained lasting relief. Improvement in the worker’s reported pain was greater than 90%, he was no longer taking any medication for pain and was back to his normal activities.
Reasons
The worker attended at the hearing before this panel together with a worker advisor who made a presentation on his behalf. No one attended on behalf of the employer. Both the worker and the worker advisor responded fully and completely to questions from the panel in the course of the hearing.
Applicable Legislation
Where an injury to a worker results in a loss of earning capacity, section 39 of The Workers Compensation Act provides that wage loss benefits are payable until the loss of earning capacity ends. Where that loss of earning capacity is caused in part by a compensable accident and in part by a non compensable pre existing condition, or the relationship between them, WCB Policy 44.10.20.10 requires the WCB to accept responsibility for the full injurious result of the accident. That Policy provides in part:
(b) Where a worker has:
1) recovered from the workplace accident to the point that it is no longer contributing to a material degree, to a loss of earning capacity, and
2) the pre-existing condition has not been enhanced as a result of an accident arising out of and in the course of the employment, and
3) the pre-existing condition is not a compensable condition, the loss of earning capacity is not the responsibility of the WCB and benefits will not be paid.
Worker’s Position
In his submissions the worker argued that the compensable injury caused an enhancement of his pre-existing condition.
Analysis
For the worker to be successful it must be demonstrated that the compensable injury or the compensable injury in concert with the worker’s pre-existing injury contributed to a material degree to his increased loss of earning capacity after May 16, 2008.
Having considered all of the evidence before us, we are satisfied that the worker had not recovered from the effects of his workplace injury by May 16, 2008. The worker reported pain radiating into his right leg as early as November 24, 2006. Those complaints persisted notwithstanding there was no objective evidence of nerve root compression. It was not until the worker responded both diagnostically and therapeutically to the epidural cortisone injection in June 2009 that the previous diagnosis of possible nerve root compression could be confirmed.
We are satisfied on a balance of probabilities that the worker’s radicular pain was caused by the workplace injury. He is therefore entitled to further workers compensation benefits from May 16, 2008 to June 23, 2009, when it was reported by the treating physiatrist that the injection had provided sustained lasting relief. The worker confirmed in his evidence before this panel that the lasting relief was in reference to his radicular pain, as distinct from his lower back pain which continues to date.
With respect to the worker’s ongoing symptoms, he advised the panel that he continues to have right low back pain with activity. We note that the worker was initially diagnosed with a back strain which was anticipated to resolve within 4 to 10 weeks. By July, 2007 the worker was reporting pain with activity but that otherwise it did not bother him “too much”.
A CT Scan performed on December 16, 2006 disclosed that the worker suffered from significant degenerative disc disease. The existence of chronic degenerative disease was confirmed by the neurologist in his report of March 23, 2007, the initial physiatrist on August 30, 2007, a WCB medical advisor on September 17, 2007, and the second physiatrist on February 8, 2008.
A WCB physiatry consultant noted on September 12, 2008 that the original diagnosis had been a muscle strain with no evidence of any neurological involvement. He noted the severe pre-existing changes and concluded that there was no evidence of any persisting physical diagnosis or injury component and that, on a balance of probabilities, the muscle strain and the aggravation of the pre-existing condition had resolved. His opinion confirmed that of a WCB medical advisor who had determined on June 11, 2008 that the aggravation of the pre-existing condition had resolved.
Those conclusions are not inconsistent with the medical information submitted prior to the hearing which included a report from the referring physiatrist. In it he noted that the pain generators were facet arthropathy, degenerative disc disease and nerve root compression. With the latter condition resolved following the epidural injection, the remaining pain generators, are according to the physiatrist, non-compensable pre-existing conditions.
The worker advisor submitted that the worker continued to suffer an aggravation or enhancement of his pre-existing condition. In support of this position, the worker advisor interpreted the comments of a physiatrist in his January 6, 2009 report, that the acute injury on a pre-existing condition suggested an enhancement of that condition. The panel notes, however, that the resolution of the worker’s nerve root compression (as noted earlier), suggests that the changes in the anatomic position of the disc, as proposed by the physiatrist, had resolved as well. Thus, the panel does not find a basis for the permanent and adverse effects on the worker’s facet arthropathy and degenerative disc disease proposed by the physiatrist. The panel notes that this finding is supported by the opinion of the WCB psychiatry consultant, in his September 12, 2008 report, that the aggravation of the pre-existing condition had resolved; while the worker continues to experience some pain in his lower back, his symptomatology is entirely consistent with the chronic nature of his pre-existing condition.
Based on this analysis, we find that the worker had suffered a temporary aggravation of his pre-existing facet arthropathy and degenerative disc disease condition, which had resolved. As such, the compensable medical conditions affecting the worker’s entitlement to wage loss benefits after June 23, 2009 were no longer related. We further note that with our finding that the worker had suffered a temporary aggravation that had resolved, it follows that we have no basis to make a finding of a permanent enhancement of those same pre-existing medical conditions at this point in time.
The appeal is therefore allowed.
Panel Members
K. Dangerfield, Presiding OfficerA. Finkel, Commissioner
P. Walker, Commissioner
Recording Secretary, B. Kosc
K. Dangerfield - Presiding Officer
Signed at Winnipeg this 11th day of February, 2010