The Appeal CommissionThe Workers Compensation Act of Manitoba

This appeal deals with whether the physical restrictions placed on the worker after January 12, 2006 are due to his pre-existing degenerative disc disease or his workplace injuries.

Background

The worker suffered two injuries to his low back – one on December 9, 2004 and the other on June 2, 2005.

The December 9, 2004 Accident

On December 9, 2004, the worker was hammering with a sledge hammer in a forward flexed position, twisting side to side, when he felt a pop and a sharp pain in his low back and left hip. He saw his family physician on December 22, 2004 complaining of pain in the L4-5 radiating into his left buttock as well as some weakness in his left leg. He was diagnosed with a lumbar strain and referred for approximately 6 weeks of physiotherapy geared toward the L5-S1 and sacro-iliac joint. The worker did not miss any time from work other than 2 weeks of holidays around Christmas time.

As the worker’s L4-5 symptoms continued, he was referred for a CT scan on February 14, 2005. The CT scan revealed pre-existing degenerative changes at the L3-4, L4-5 and L5-S1 levels:

“At L3-L4 level, there is mild diffuse annular disc bulging. There is no evidence of disc herniation, spinal stenosis or nerve root involvement.

At L4-5 level, there is [Grade] I spondylolisthesis secondary to facet [osteoarthritis] and hypertrophy. There is diffuse annular disc bulging. Mild right paracentral broad-base disc protrusion is present. Together there is mild to moderate central stenosis.

At L5-S1 level, there is mild diffuse annular disc bulging. There is no evidence of disc herniation, spinal stenosis or nerve root involvement.”

The worker continued to complain of pain into his left leg with heavy lifting. His family physician thought that he was permanently disabled due to his back condition and should not do any heavy lifting over 20 pounds or any repetitive bending.

A WCB medical advisor (“the WCB medical advisor”) reviewed the file on March 14, 2005. She thought that given the worker’s significant pre-existing changes in the lumbosacral spine and the absence of back pain or impairment in mobility or strength at the time of his discharge from physiotherapy in February 2005, his need for restrictions was preventive in nature.

On March 18, 2005, a WCB case manager wrote to the worker to tell him that his permanent medical restrictions consisted of no repetitive lifting and no lifting over 20 pounds but that these medical restrictions were a result of his pre-existing medical condition that was unrelated to the workplace injury.

The June 2, 2005 Accident

On June 2, 2005 the worker injured his back, left hip and leg again after lifting railway ties for over one week. He went to an emergency hospital facility and was diagnosed with mechanical back pain. He was referred to physiotherapy for approximately 6 weeks starting on June 13, 2005. The physiotherapist noted that the worker’s symptoms were recurrent low back pain (from the December 9, 2004 accident) with left sacro-iliac joint dysfunction. He remained off work for 3 months and returned to work at modified duties in September 2005.

On October 6, 2005, the WCB medical advisor reviewed the 2005 claim. She felt that the worker had not completely recovered and still required temporary work restrictions. She did however think that another CT scan should be done to rule out a L4-5 disc herniation. This was done on November 10, 2005 and was compared with the previous CT scan findings of February 14, 2005. The November 10, 2005 CT scan noted the following:

“At L3-4, note is made of diffuse annular bulging with a slightly more left lateral component which does contact the left L3 nerve root without convincing evidence of nerve root compression. This has not changed significantly from the previous study.

At L4-5, there is a [Grade] I spondylolisthesis secondary to facet [osteoarthritis] and hypertrophy. Again seen is diffuse annular bulging. Mild right paracentral broad-based disc protrusion is again seen with associated mild to moderate central spinal stenosis.

At L5-S1, mild diffuse annular disc bulging is identified. There is no evidence of disc herniation, spinal stenosis or nerve root involvement.

Impression: Multi-level disc disease as described above. No significant change from the prior study is identified.”

The WCB medical advisor reviewed the November 2005 CT scan and commented:

“There is portion of L3-L4 diffuse annular disc bulging [with] a slightly more [left] lateral component contacting the [left] L3 nerve root without convincing evidence of nerve root compression. This [left] sided L3-L4 disc bulge was not reported on the Feb 14/05 study. [The worker’s] present claim relates to a June 2/05 workplace incident. [He] was lifting railway ties for over a week and began to experience [left] low back/[left] hip/[left] leg pain in early June/05. He then present with [decreased] strength [left] quads with atrophy and [decreased] reflexes [left] knee. These findings correspond to the [left] L3 nerve root irritation and dysfunction…”

The worker was then called in for an examination with the WCB medical advisor on January 12, 2006. The worker told the WCB medical advisor that he improved after his December 2004 accident but felt that he had never fully recovered. The June 2005 accident was similar in nature but more severe in symptoms. At the time of the call-in examination, he felt that his back had returned to his baseline status following the December 2004 workplace accident. Based on this history and a physical examination, the WCB medical advisor changed her initial opinion and concluded that the worker likely sustained an L3-L4 disc injury at the time of his December 2004 workplace accident and that this injury was likely enhanced at the time of the June 2005 workplace accident. She further indicated that restrictions would be appropriate and would likely be long term in nature.

On January 31, 2006 the WCB case manager wrote to the worker to tell him that workplace restrictions were put in place for a 6 month period; they were later revised on February 8, 2006. The employer appealed the ongoing restrictions as being related to the worker’s compensable injuries to Review Office. Review Office sought the medical advice of a WCB orthopaedic consultant who reviewed the file on August 10, 2006. His opinion was as follows:

“I do not think it has been established that the claimant has sustained a disc injury with either compensable injury. He does have significant pre-existing degenerative changes particularly at L4-L5 level which may have been temporarily aggravated but certainly not enhanced and from which he appears to have recovered. Any imposition of “restrictions” would be preventative (sic) in nature due to the condition of his spine and need not necessarily be long term in nature. He may continue to have ongoing intermittent problems due to the progressive nature of these degenerative changes.”

Evidence at the Hearing

At the hearing, the worker described his mechanism of injury in the 2004 and 2005 workplace accidents as well as the progressive resolution of his symptoms since 2005.

He explained that after his December 2004 accident he continued to work at his regular duties but felt stiff and achy. His condition worsened in June 2005 after a week of lifting and carrying railroad ties. The worker explained that his left leg got progressively stiffer to the point that it felt like a charley-horse and he was unable to move. By January 2006 he was back to feeling the way he did before his June 2005 accident. Since that time, he has become progressively stronger to the point that he returned to his regular duties in February 2007. He does however continue to be careful in carrying out his duties so as to not re-injure himself.

Worker’s Position

The worker says that his restrictions beyond January 12, 2006 are required as a result of the 2004 and 2005 accidents. He relies on the WCB medical advisor’s opinion that he suffered an injury to his L3-4 disc on December 9, 2004 and that this injury was enhanced by his June 2, 2005 accident.

Employer’s Position

The employer disagrees with the worker. It says that the worker’s ongoing restrictions beyond January 12, 2006 are simply preventive in nature. It says that the worker’s mechanism of injury and symptomotology after both accidents are consistent with a simple aggravation of his pre-existing degenerative back condition.

Analysis

To accept the worker’s appeal we must find on a balance of probabilities that his workplace restrictions beyond January 12, 2006 are related to his 2004 and 2005 compensable injuries. We are unable to make that finding.

Based on the evidence before us, we find that the 2004 and 2005 accidents caused the worker an aggravation to his pre-existing degenerative back condition and more particularly to the L4-5 and L5-S1 area. We make this finding on the basis of the worker’s mechanism of injury and his reported symptoms and clinical findings between December 2005 and January 2006.

We have turned our minds to the WCB medical advisor’s opinion that the worker injured his L3-4 disc in 2004 and that this injury was enhanced by the June 2005 accident. We are unable to place any weight on this opinion. Indeed, the worker’s symptoms and progressive resolution to his baseline before the 2005 accident are consistent with an aggravation of a pre-existing condition; there is a lack of evidence that the L3-4 disc was causative of any of the worker’s symptoms. Further, there is a lack of radiological evidence to support the proposition that the worker’s pre-existing degenerative disc condition was in any way enhanced.

Based on this finding of an aggravation of a pre-existing degenerative disc condition, as well as the evidence that in January 2006 the worker was feeling in the same condition he was prior to the June 2005 accident when he was working his regular duties, we are unable to find that the worker’s continuing need for restrictions beyond January 12, 2006 are as a direct result of his 2004 and 2005 accidents.