The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

The worker filed a claim with the Workers Compensation Board ("WCB") for a back injury that occurred at work on September 18, 2007. Fourteen days later, on October 2, 2007, the worker underwent spinal surgery.

Following several appeals, the WCB's Review Office ultimately determined that the September 18, 2007 accident enhanced the worker's pre-existing degenerative back condition and responsibility was accepted for the surgical procedure and the worker's wage loss benefits. The employer disagreed with Review Office and took the position that the medical evidence did not support that the compensable incident enhanced the worker's pre-existing condition and therefore the surgery could not be attributed to the compensable injury. It was felt that the worker had recovered from the effects of her compensable injury by March 7, 2008 and was therefore not entitled to benefits beyond that date. A hearing was held on January 31, 2011 to consider the matter.

Issue

Whether or not responsibility should be accepted for the worker's October 2, 2007 spinal surgery; and

Whether or not the worker is entitled to wage loss benefits beyond March 7, 2008.

Decision

That responsibility should not be accepted for the worker's October 2, 2007 spinal surgery; and

That the worker is not entitled to wage loss benefits beyond March 7, 2008.

Decision: Unanimous

Background

The worker reported to the WCB that she injured her low back on September 18, 2007 due to the following work related accident:

I was lifting a solvent mixture (approx. 20 lbs) and I was pouring it into smaller bottles when I felt an extremely sharp pain in my back where it shot down both legs.

The worker reported that the last date she worked following the incident was September 20, 2007. She reported that she had a prior back problem related to a car accident but it never stopped her from working. The worker reported that she was seeing a doctor on September 26 and was going to the pain clinic on September 28, 2007.

The employer's accident report dated September 25, 2007 indicated that the worker reported the September 18, 2007 accident on September 24, 2007. The accident was described as: "Employee twisted her back, pouring liquid from a heavy solvent container (12 liter glass bottle containing 8 liters of liquid) into 4 liter bottles." Further information on the report stated:

Incident happened on September 18 but was considered minor and was consequently not reported. Employee finished the work day on Sep. 18, working all day Sep. 19 and 5 hours on Sep. 20, 2007. The remaining 3 hours on Sept. 20, plus Friday Sept. 21 and Monday Sep 24 were booked off as vacation to go on a trip to Saskatchewan. On Monday Sep. 24 at 17:00 employee informed her supervisor that she had to cancel her trip because of severe back pain and was unable to return to work on Tuesday Sep 25. Employee will see a doctor on Sep 26, 2007. Last week she volunteered to her supervisor the information that she has a history of back problems because of a severe car accident 6 years ago; at that time her supervisor already instructed employee not to lift things and to ask for assistance if needed.

On September 26, 2007, the treating physician diagnosed the worker with a lumbar back strain with a large L4-5 disc protrusion.

On October 1, 2007, the worker advised her adjudicator that she saw a doctor at the pain clinic on September 28 and had a CT scan that day and an MRI the next day. The worker said they compared the results to a CT scan she had back in March of 2007 and decided that she should be referred to a surgeon to be assessed for surgery. The worker advised that her MPI claim ended in 2002 and it was ruled after an appeal that she was no longer injured and had recovered from her injury. The worker said she had been taking pain killers for years but did not remember how long. The worker noted that she had back pain previously but not a disc protrusion that she believed was related to her pouring 12 liters of liquid into 4 litre jugs.

On October 2, 2007, the worker underwent back surgery and the operation report stated, in part:

"…a large disc herniation exiting L4 and traversing L5 nerve roots. This thecal sac was mobilized over the extruded disc material and this was removed in total. This disc was sequestrated."

In claim notes dated October 24, 2007, a WCB adjudicator documented that he discussed the worker's file with a WCB orthopaedic consultant. He noted that the worker had a pre-existing condition and that she had been functioning until the workplace accident. This suggested an aggravation. Based on this finding, the worker's claim for compensation was accepted as an aggravation of a pre-existing L4-5 disc herniation pending the review of additional medical information.

Information regarding the worker's prior back history was obtained. In a report dated June 27, 2002, the family physician noted that the worker was involved in a motor vehicle accident on December 23, 2000. When seen for an examination on May 7, 2001, the worker had bilateral lower lumbar paraspinal tenderness, greater on the right side. There was no dorsal thigh tenderness. Forward hip flexion was about 3 inches above the patella. Hip extension, lateral hip flexion and twisting to the left and right was noted to be normal. Bilateral straight leg raising was normal. The worker was prescribed Celebrex.

When next seen on May 28, 2001, the worker complained of only slight pain. Range of motion of the hips that day was noted to be normal and there was no tenderness. The physician's diagnosis was resolved lumbar back strain/muscle spasm. When seen again on April 15, 2002, the worker had tenderness in the lumbosacral region and hip extension was normal but painful. When seen next on April 20, 2002, the worker indicated that she could not work as a waitress due to her back pain.

In a report dated June 26, 2002, an orthopaedic specialist indicated that he saw the worker on May 16, 2002. X-rays were taken and they showed a moderate degenerative narrowing at the L5 intervertebral disc with moderate sub-chondral sclerosis.

On October 17, 2002, a CT of the lumbar spine showed a small central disc protrusion at the L5-S1 level just contacting the anterior thecal sac and left S1 nerve root but without gross displacement or impingement.

In a report from a health clinic dated March 4, 2004, the worker was diagnosed with mechanical back pain. The worker was on medication for pain control. Examination showed no neurological signs.

On November 13, 2005, the worker was seen at a pain and injury clinic for ongoing low back pain related to the earlier motor vehicle accident ("MVA") which had been increasing for the last six months. The worker was assessed with mechanical low back pain and sleep disturbance.

In a report dated February 21, 2007, an anesthesiologist stated that the worker was referred for treatment by her family physician for chronic low back pain since the MVA of December 23, 2000. "Over the past three months she complains of increasing left leg pain and numbness through her left leg to her left foot." The impression was that the worker suffered from discogenic back pain and an acute exacerbation (with possible nerve root compression) superimposed on her chronic pain. The plan was to a request a lumbosacral CT scan to rule out disc herniation or root compression.

A CT of the lumbosacral spine dated March 22, 2007 was compared with a previous one dated October 17, 2002. The report described a new large disc herniation at L4-5.

In a report dated April 13, 2007, the anesthesiologist indicated that the worker was assessed on April 4, 2007. It was noted that the recent CT scan showed a large extrusion of disc material at the L4-L5 level and that the L5 roots were contacted bilaterally. The report stated, "When she is done her exams, we will proceed with injection therapy. She feels she has given this disc six months to settle on its own and it has not. The planned injection will be a left L4 transforaminal epidural steroid injection or a L4-L5 translaminar epidural steroid injection…If this fails I will refer her in short order to spine surgery."

As noted earlier, after the workplace accident of September 18, 2007, the worker was referred for a CT scan. The CT of the lumbar spine dated September 28, 2007 stated: "There is a very large L4-5 disc herniation. This is quite diffuse but lateralized a little to the left. No abnormality is seen at L5-S1."

The worker had an MRI examination on September 29, 2007. The results showed a large L4-5 disc herniation with marked canal encroachment. This was quite broad-based but lateralized a little to the left. The remainder of the scan was unremarkable, apart from very minor degenerative change at L2-3 and L5-S1, according to the report.

In a report dated October 10, 2007, it was documented that the worker underwent an L4-L5 discectomy for a large L4-L5 disc herniation on October 2, 2007.

In a report dated October 19, 2007, the anesthesiologist stated:

…She represented on September 28, 2007 with an acute worsening. She states that while at work she was bent down and lifting and suffered sharp excruciating pain that disabled her and brought her to the ground. She had been bed bound for the previous week waiting for partial pain resolution. She came into clinic with 10/10 pain. Her whole leg had now gone numb and while there was no overt weakness, there was difficulty with ambulating due to the significance of the pain.

This was an acute event and this was clearly the worst shape that I ever seen [the worker] in. An emergency CT scan was performed that day. This showed a large L4-L5 disc that was obliterating her canal. Her lack of significant bladder symptomology was surprising. Spine surgery was re-consulted and she had surgery within the following week…What I can say is that there was a significant and new change in her spine assessment in the two weeks that I saw her in September 2007. She had an abrupt change in her functional status and new CT scan findings in keeping with her deteriorating clinical status.

On December 7, 2007, primary adjudication referred the file to a WCB orthopaedic consultant for his opinion. In his response dated January 4, 2008, the WCB orthopaedic consultant stated:

"…it is clear that the claimant developed a very large L4-5 disc herniation/sequestration from at least 1996 to the assessment by (Pain Centre physician) February 20, 2007. She was continuously symptomatic through 2007, including an assessment September 14, 2007, by (Pain Centre physician) four days before the claimed injury, at which time it was reported that there had been no sustained response to the five injection treatments between May and August 2007. During this entire period she was a candidate for surgical treatment, in view of the extent, level and nature of the pathology, and a consultation was in place with an orthopaedic spine surgeon. The workplace injury was in the nature of a low back strain…the diagnosis of the pre-existing condition was an L4-5 disc sequestration, large enough to involve the left L5 root to a significant degree and the right L5 root to a lesser degree. The three imaging studies noted above demonstrated no significant difference in the size and extent of the disc sequestration in the studies of March 22, 2007, and September 28 and 29, 2007…in my opinion, the claimant was as much a candidate for surgical treatment at all times from February through August 2007, as she was in September 2007, but did not wish to proceed to surgery for personal reasons…Regarding aggravation or enhancement, the evidence does not establish that the compensable injury resulted in a material aggravation of the pre-existing pathology for which she subsequently had surgical treatment. In my opinion…the Workers Compensation Board should not accept responsibility for the surgical procedure of October 2, 2007…The average recovery period from a lower back strain would be in the region of six to eight weeks."

On February 20, 2008, the WCB orthopaedic consultant reviewed chart notes from the anesthesiologist for the period May 2007 to September 2007 as well as the worker's attendance records He stated:

…From this information, the most significant are the comments on September 14, 2007, which indicate severe progression of symptoms, uncontrolled by medication and epidural steroid injections and some evidence that the physician was concerned regarding cauda equina complication and proceeding to immediate surgical consultation. This was four days before the compensable injury…My opinion of January 4, 2008, is unchanged.

On March 3, 2008, the worker was advised of the WCB's position that she had recovered from the effects of her compensable low back strain injury and that her current difficulties related to her pre-existing condition. As such, no responsibility would be accepted for the October 2, 2007 spinal surgery and wage loss benefits would end on March 7, 2008. The decision was based on the opinion expressed by the WCB orthopaedic consultant on January 4, 2008 and February 20, 2008.

On July 10, 2008, a worker advisor appealed the March 3 decision to Review Office. The worker advisor submitted that the worker had a loss of earning capacity beyond March 7, 2008 and that benefits were payable in accordance with the WCB's policy on pre-existing conditions. The worker advisor argued that the need for surgery was expedited and necessitated as a direct result of the workplace accident and an enhancement was created as a result of the compensable accident.

In a decision dated September 9, 2008, Review Office confirmed that responsibility should not be accepted for the surgical procedure of October 2, 2007 and that wage loss benefits were not payable beyond March 7, 2008. Review Office agreed with the WCB orthopaedic consultant that the worker's L4-L5 disc herniation pre-dated her injury of September 18, 2007. Review Office found that surgery was performed to correct a severe disc herniation which pre-existed the injury of September 19, 2007, and that the worker incurred an aggravation of that condition. It stated that the WCB recognized the aggravation but there was no clinical evidence on file that the compensable accident enhanced the condition.

On October 31, 2008, the worker advisor provided Review Office with an October 1, 2008 report from the anesthesiologist for consideration. The physician stated in his report:

I disagree with the WCB orthopaedic surgeon's opinion that the need for surgery predated [the worker's] accident of September 18, 2007….as of her workplace accident of September 18, 2007, there was a dramatic change in her symptomatology including symptoms of urinary hesitancy suggestive of quantum syndrome. This established in a need for immediate spine surgery consultation. As a result of this consultation a need for surgery was determined and the patient underwent surgery subsequently. I disagree with the orthoapedic consultant's opinion that the evidence does not establish the compensable accident injury resulted in material aggravation of the pre-existing pathology. The history and physical performed on September 28, 2007 established a dramatic change in [the worker's] condition with decrease (sic) sensation of the lateral aspect of her left foot and greatly increased pain…[the worker] is not suffering from a lower back strain. This is why her recovery period is extended…Her current inability to work continues to be related to her accident and the consequences of her surgical treatment. Surgical recovery is often extended in patients with severe pre-existing pain.

On November 19, 2008, Review Office upheld the decision that the responsibility should not be accepted for the worker's surgical procedure of October 2, 2007 or for wage loss benefits beyond March 7, 2008. Review Office indicated that it was still of the opinion that the surgery was to correct a significant disc problem that was captured through imaging studies prior to September 18, 2007 with the medical community being aware of the severity of the condition before the compensable injury. It felt that the worker incurred a strain superimposed on a severe pre-existing condition on September 18, 2007. It did not feel the medical evidence established that the injury of September 18, 2007 enhanced the pre-existing condition. It felt that this was just one of many aggravations of this condition the worker had incurred over time.

In a submission to Review Office dated February 23, 2009, the worker advisor referred to a report from the worker's surgeon dated February 13, 2009. She noted that the surgeon supported a relationship between the worker's compensable accident of September 2007 and the need for surgical intervention of October 2, 2007. In his report, the surgeon indicated the following:

• [the worker's] resultant injury with respect to her September 18, 2007 injury was that of a left L4 and L5 radiculopathy secondary to a left L4-L5 disc herniation.

• I disagreed with the Workers Compensation Board Orthopaedic Consultant's opinion that the workplace accident did not result in material aggravation of pre-existing pathology for which she certainly had surgical treatment. I am disagreeing in that the patient states that her pain intensified after this workplace injury, not allowing her to function to a greater degree, requiring her to remain bedridden until surgical intervention was undertaken. She states that prior to this injury, her pain was severe, although tolerable.

• I do not think that had [the worker] had an exacerbating injury on September 18, 2007 that she would have required surgery. However, if she had had a significant fall or been involved in a significant axial blow to the spine, this certainly could have exacerbated the symptomatology experienced related to the L4-L5 disc herniation.

On March 2, 2009, Review Office referred the case to the WCB orthopaedic consultant to review the surgeon's recent report. In response dated March 24, 2009, the WCB orthopaedic consultant stated that none of the imaging studies reported a disc sequestration. He also stated that his previous opinion was unchanged, that the compensable injury of September 18, 2007 did not result in an aggravation or enhancement of the pre-existing condition of L4-5 disc herniation.

On April 1, 2009, Review Office upheld the decision that no responsibility should be accepted for the worker's October 2, 2007 surgical procedure on her lumbar spine or for wage loss benefits beyond March 7, 2008. In making its decision, Review Office quoted the opinion outlined by the WCB orthopaedic consultant that was outlined on March 24, 2009. Review Office maintained the position that the worker was in severe low back and radicular pain and there was a chronicity of the worker's pain complaints through the millennium which escalated in 2007 leading into the September 18, 2007, compensable injury. It felt that the October 2, 2007 surgery was required to correct a severe and significant disc problem that was seen through imaging studies prior to September 18, 2007.

On June 29, 2009, the worker advisor provided Review Office with a June 10, 2009 report from the treating orthopaedic surgeon. The worker advisor pointed out to Review Office that the October 2007 operative report did in fact identify a disc sequestration and that the treating surgeon related his diagnosis to the compensable accident.

In his report to the worker advisor dated June 10, 2009, the treating orthopaedic surgeon stated:

• the operative note from October 2007 clearly stated under "Operative Procedure" that the disc was sequestered;
• the worker would have required surgery with an exacerbating injury to remedy the disc injury and neurologic symptoms related to the L4-L5 level;
• the finding of a sequestered disc during the October surgery would support that this finding was different from what was seen on the CT scan before the worker's compensable accident as well as the MRI post-accident;
• the average recovery period after back surgery would be 6 to 8 weeks. In the case such as the worker's, recovery from back surgery could take well beyond 6 to 8 weeks;
• the worker had a chronic pain response/behavior related to the workplace injury of September 2007. This played a significant variable in delaying her recovery from the December 2008 surgery;
• the September 18, 2007 accident enhanced a pre-existing condition of the L4-5 disc herniation resulting in radicular pain which could not be effectively treated with conservative therapy therefore requiring the worker to undergo the discectomy in October 2007.

In a July 30, 2009 decision by Review Office, the worker was advised that based on the further explanation provided by the treating surgeon, responsibility was now being accepted for the worker's surgery of October 2, 2007 and that wage loss benefits were payable beyond March 7,

2008. On January 13, 2010, Review Office clarified its decision to the case manager that "WCB has accepted responsibility for an L4-5 disc sequester as a result of the September 18, 2007, workplace injury, which has resulted in an enhancement of a pre-existing disc herniation."

Legal counsel representing the employer appealed Review Office's decision of July 30, 2009 to the Appeal Commission and a hearing was arranged.

Reasons

At the hearing, reliance was made on the May 31, 2007 pre-employment physical examination which cleared the worker as fit for work without restrictions. The representative from the employer testified as to the concerns they had with respect to the reliability of these medical reports. Given that the worker had been referred for surgical consult by her treating physician just one month prior, the panel accepts that the pre-employment medical clearance was not a reliable indicator of the worker's actual physical status at that time.

In the panel’s opinion, the worker had pre-existing symptomatology prior to the September 2007 accident, which was not responding to injection therapy and which had already been referred for surgical consult. The panel agrees with the WCB orthopedic consultant that the worker remained as much a candidate for surgery before as with after the workplace injury. As the evidence does not satisfy us that the worker suffered an enhancement of her pre-existing L4-L5 disc herniation, we find that responsibility should not be accepted for the worker's October 2, 2007 spinal surgery. The panel is of the view that the compensable injury suffered by the worker was limited to a lumbar strain. The worker therefore had two parallel medical conditions, one compensable (the muscle strain injury) and the other not (the severe degenerative disc disease). The initial medical reports after the accident address the strain injury, but the focus then shifted to the very dominant neurological issues facing the worker. The strain injury may have resolved in as little as a week or two, and would be expected to be covered by the 6 to 8 week norms referenced in the medical evidence. We therefore find that the worker's entitlement to wage loss benefits should have ended eight weeks after the accident and certainly would not have extended beyond March 7, 2008.

The employer's appeal is allowed.

Panel Members

L. Choy, Presiding Officer
A. Finkel, Commissioner
P. Walker, Commissioner

Recording Secretary, B. Kosc

L. Choy - Presiding Officer

Signed at Winnipeg this 23rd day of March, 2011