The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

An Appeal Panel hearing was held via teleconference on June 26, 2002, at the request of an advocate, acting on behalf of the claimant. The Panel discussed this appeal on June 26, 2002 and again on August 20, 2002.

Issue

Whether or not the worker is entitled to wage loss benefits beyond January 20, 2000.

Decision

That the worker is not entitled to wage loss benefits beyond January 20, 2000.

Decision: Unanimous

Background

While employed as a healthcare aide on April 5, 1999, the claimant was trying to prevent a resident from falling out of bed when she felt lower back pain when the resident grabbed the side rail of the bed. The claimant was seen by a chiropractor for treatment on April 6, 1999 and was diagnosed with a left sacroiliac strain/sprain. The claimant was also assessed by a general practitioner and was referred for physiotherapy treatment and a CT scan. The Workers Compensation Board (WCB) accepted the claim and wage loss benefits were paid.

On June 15, 1999, a CT scan of the lumbar spine revealed mild to moderate disc bulging at L4-L5 and slight bulging at L3-L4 but no evidence of neural compromise.

In a June 28, 1999 letter, the attending physician referred to the CT scan results and stated that as long as the claimant avoided lifting heavy objects she did not seem to be in any discomfort whatsoever. The physician requested that the claimant be assessed at the WCB to determine how to proceed with the claimant's current difficulties, given that her work involved heavy lifting.

On July 13, 1999, a WCB medical advisor examined the claimant. He believed that the claimant likely suffered from mechanical low back pain with aggravation of a pre-existing facet arthropathy. The medical advisor recommended that the claimant receive another four weeks of physiotherapy treatments and then she could return to work without restrictions.

In a progress report dated July 23, 1999, the attending physician reported that the claimant still showed definitive signs of root compression despite the lack of evidence on the CT scan. The claimant had persistent numbness, shooting pain and weakness of the left ankle.

Following an MRI scan of the lumbar spine on September 10, 1999, a WCB medical advisor wrote to the attending physician on September 28, 1999. He stated, in part, "The MRI scan again shows pre-existing degenerative disc disease mainly at L4-5 level. This showed grade 1 spondylolisthesis in addition to facet joint degeneration changes. There was also mild right foraminal narrowing and mild-to-moderate left foraminal narrowing as a result of the facet joint degenerative changes. Incidentally, there was also an annular tear noted on the right side." The medical advisor believed that the annular tear was an incidental finding and was of the opinion that the claimant's ongoing back problem was likely due to pre-existing facet joint degenerative changes causing foraminal narrowing. Based on the call-in examination findings, the 3/5 Waddell's sign and other inconsistencies, it was the medical advisor's opinion that the claimant's ongoing back problem was now related to her pre-existing degenerative disc disease and that the effects of her April 5, 1999 compensable injury had resolved.

In response to several questions posed by primary adjudication, the attending physician reported on October 7, 1999, that he had been treating the claimant since December 1997 and there was no history of pre-existing condition before the 1999 accident. April 20, 1999 was the first time that the claimant mentioned back problems. There was no history of any x-rays, CT scans or MRI's prior to this date.

On November 25, 1999, an orthopaedic surgeon commented that the claimant's condition was purely mechanical lumbar back pain with a lot of sympathetic overload and sciatic symptomatology that was not proven by imaging. The claimant was not a candidate for surgical stabilization or intervention. Further x-rays were recommended to rule out instability at the L4-5 level.

A CT myelogram dated November 25, 1999 revealed the following:

"At L2-L3 and L3-L4 level, there is diffuse annular disc bulging without evidence of disc herniation, spinal stenosis or nerve root involvement.

At L4-L5 level, there is anterolisthesis secondary to facet OA. There is no evidence of disc herniation, spinal stenosis or nerve root involvement. Moderately severe facet OA is noted.

At L5-S1 level, there is diffuse disc bulging without evidence of disc herniation, spinal stenosis or nerve root involvement. The visualized SI joints are normal."

On December 20, 1999, a WCB medical advisor reviewed the case. The medical advisor was of the opinion that the claimant's ongoing low back pain was not related to the compensable injury but rather to her pre-existing degenerative disc disease. On January 13, 2000, the WCB medical advisor contacted the claimant's treating physician and he was in agreement that the claimant's present condition was not related to the compensable injury.

In a January 14, 2000 decision, primary adjudication determined that the claimant had recovered from the effects of her workplace injury and that her current difficulties were due to her pre-existing condition. The claimant was informed that wage loss benefits would be paid to January 20, 2000 inclusive and final.

On January 17, 2000, the claimant's orthopaedic surgeon referred to the results of lumbosacral spine x-rays that were taken on December 17, 1999. Based on these findings, the surgeon noted that the L4-5 segment was quite unstable which gave the claimant a back at risk. A referral to a neurosurgeon was recommended to consider surgical stabilization. On February 9, 2000, a WCB medical advisor reviewed this report and was of the view that the claimant's instability of the L4-5 segment was related to her pre-existing degenerative spondylolisthesis.

On May 29, 2001, the attending physician provided the WCB with up-to-date information concerning the claimant's physical status and medical treatment. The physician provided the opinion that the claimant had a pre-existing back problem which was enhanced by her work activities as a nurses aide and that she was unable to work given her severe lower back pain which restricted all of her activities.

Following review of the case by a WCB medical advisor on July 14, 2001, primary adjudication wrote to the claimant on July 31, 2001. It was the WCB's opinion that the claimant had recovered from her workplace injury and that her pre-existing condition was the cause of her ongoing problems.

On August 31, 2001, Review Office considered the case based on an appeal submission from the claimant's advocate, an opinion which was expressed by a WCB orthopaedic consultant on August 28, 2001 and the WCB's policy on pre-existing conditions. Review Office determined that the claimant was not entitled to benefits after January 20, 2000 based on the weight of medical evidence which supported that the claimant's problems after January 2000 were not due to the compensable injury but were primarily due to her pre-existing back condition. On May 4, 2002, the claimant's advocate appealed Review Office's decision and an oral hearing was held via teleconference on June 26, 2002.

Following the hearing and discussion of the case, the Appeal Panel requested a consultative report from a physical medicine and rehabilitation specialist who was to assess the claimant on July 23, 2002 along with a copy of a 2001 CT myelogram report. On August 2, 2002, all interested parties were provided with a copy of the specialist's report dated July 24, 2002 and a CT myelogram report of February 22, 2001 and were asked to provide comment. On August 20, 2002, the Panel met to render its final decision on the issue under appeal.

Reasons

This case involves a health care worker who injured her lower back in a workplace accident in April 1999. Her claim for compensation was accepted and benefits were paid accordingly.

In January 2000, the board determined that she had recovered from the effects of her workplace injury and benefits were terminated. Her appeal to Review Office was not successful. She appealed that decision to this Commission.

For her appeal to be successful, the Panel would have to determine that any medical problems with her lower back, beyond January 20, 2000 were causally related to her workplace accident. We were not able to make that determination.

In coming to our decision, we made a thorough review of the claims file and held an oral hearing, via teleconference, at which we heard testimony from the claimant, as well as argument from her advocate. Subsequent to the hearing, and prior to making our decision, we sought further medical evidence, including the report of a medical examination of the claimant, scheduled but not done at the time of the hearing.

There is no doubt that the claimant has extensive and serious problems related to her back. However, we were unable to determine that these problems are causally related to her workplace injury.

The key to the issue before the Panel was whether or not the claimant's current medical problems with her lower back are attributable to her compensable injury or to pre-existing conditions. In considering this issue, we looked to the board policy on pre-existing conditions, 44.10.20.10. The relevant sections read as follows:

1. WAGE LOSS ELIGIBILITY

1. Where a worker's 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, the Worker's Compensation Board will accept responsibility for the full injurious result of the accident.
   
   
2. 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.

There is considerable medical evidence on the file which indicates that the claimant does have pre-existing problems with her lower back. In particular, we note the following:

• CT Scan - June 1999 - "The left-sided facet joint at L4/L5 is moderately degenerative with narrowing of the joint space and osteophyte formation laterally."
  
  
• X-ray - July 1999 - "There is Grade I spondylolisthesis at the L4-5 level. There is Grade I retrolisthesis at the L3-4, L2-3 and L1-2 levels. . The spondylolisthesis at L4-5 is almost Grade II . There are moderate osteoarthritic changes in the facet joints, moderately advanced in the lower lumbar spine."
  
  
• MRI - September 1999 - same findings as the above x-ray, especially in respect of the spondylolisthesis and the facet joint degenerative changes.
  
  
• CT Myelogram - November 1999 - "At L2-L3 level, there is diffuse annular disc bulging . At L4-L5 level, there is anterolisthesis secondary to facet OA .moderately sever facet OA is noted. . At L5-S1 level, there is diffuse disc bulging ."
  
  
• CT Scan - February 2001 - "There is a grade I anterior listhesis of L4 on L5, associated L4,5 disc space narrowing. . Extensive facet OA changes are present throughout the lumbar spine bilaterally, most marked at the L4, 5 level, particularly on the left side.
  
  
• In a May 2001 letter, her family doctor wrote that it was his opinion that she "had a pre-existing back problem which was enhanced by injuries sustained while performing her duties as a nurses aid."

We placed considerable weight on the opinion expressed by the Orthopaedic Consultant to Review Office, who wrote:

• "The claimant has evidence of extensive degenerative disc disease and facet osteoarthritis of the lumbar spine occurring at several levels with an associated anterolisthesis of L4 on L5 due to degenerative facet arthritis."
  
  
• "The pre-existing condition could have been aggravated by the CI [compensable injury] and could also lead to a prolonged recovery from the CI."
  
  
• "The original symptoms arising out of the CI had long ceased to act in my opinion, and the claimant's ongoing symptomatology are related to the extensive pre-existing degenerative osteoarthritis of the posterior facet joints in association with degenerative disc disease."
  
  
• "I would not attribute any of these reported changes to have occurred as a result of the CI. As noted in the file, the original mechanism of injury is not such that it would keep the claimant off work for over 10 months."

This opinion by the orthopaedic consultant confirms the evidence on the file supporting the pre-existing conditions.

We also considered the matter of whether or not the compensable injury enhanced the pre-existing condition. If we were to find that it had, then board responsibility for some benefits would ensue. We did not find that to be the case. Policy 44.10.20.10, already noted above, includes the following definitions:

Aggravation: The temporary clinical effect of a compensable accident on a pre-existing condition such that the pre-existing condition will eventually return to its pre-accident state unaffected by the compensable accident.

Enhancement: Where a compensable injury permanently and adversely affects a pre-existing condition or makes necessary surgery on a pre-existing condition.

Based on the medical evidence on file and noted above, as well as on the opinion expressed by the Orthopaedic Consultant to Review Office, we have concluded - on a balance of probabilities - that the claimant incurred an aggravation to her pre-existing condition, but not an enhancement.

We also note Board Policy 44.20.10.40, which specifically deals with spondylolisthesis. The policy reads, in part:

Where a claimant is considered to have a pre-existing spondylolysis or spondylolisthesis condition and there is a relationship between the condition and the compensable injury, as determined by the Board, the Board will accept on-going responsibility on an aggravation, enhancement or accelerated degeneration basis.

. ...

Adjudication opinions may be based on the presence or absence of objective and subjective supporting evidence, however, there would have to be clearly documented clinical findings upon which a judgement of aggravation, enhancement, or eventually, acceleration, could be assessed or judged to have taken place. (Our emphasis.)

As already noted above, it is our conclusion that the claimant did incur an aggravation, but not an enhancement.

Based on the foregoing, the preponderance of evidence has led us to conclude that the decision of the Review Office was correct and should be upheld.

Accordingly, the appeal is dismissed.

Panel Members

T. Sargeant, Presiding Officer
A. Finkel, Commissioner
M. Day, Commissioner

Recording Secretary, B. Miller

T. Sargeant - Presiding Officer
(on behalf of the panel)

Signed at Winnipeg this 25th day of September, 2002