The Appeal CommissionThe Workers Compensation Act of Manitoba

Introduction

This appeal deals with the relationship between the worker’s ongoing back complaints and his compensable injury and more particularly, the credibility of those ongoing complaints.

Background

The worker is a heavy duty mechanic. This requires him to use various movements of bending, lifting, stretching, reaching and crouching in various positions and with various weights sometimes in excess of 100 pounds.

On July 7, 1999, the worker slipped and fell backwards onto a flight of steel stairs, landing with his back on the stairs. He complained of pain, numbness and tingling into his right lower leg. On examination, his treating physician noted that the worker had 50% decrease in range of motion in all directions. He was diagnosed with a probable disc protrusion and arrangements were made for him to undergo physiotherapy and an x-ray examination which later revealed spina bifida occulta of S1. There was no narrowing of the discs.

By August 25, 1999 the worker felt that he had improved by about 70%, and his treating physician thought that he could return to modified duties which he did. The worker found however that he was only able to work 4 hours a day and was sore by the end of that shift. He was re-examined by the treating physician on September 3, 1999 who commented that the worker seemed to be in worse condition and presented with muscular spasm. He advised the worker to remain on modified duties, see a chiropractor and continue with home exercises.

On September 15, 1999 he saw the chiropractor who diagnosed him with a lumbosacral sprain and facet syndrome but advised that radiculopathy should be ruled out. He also commented that the worker displayed evidence of “illness behaviour” that needed to be monitored.

A CT scan was performed on September 23, 1999. It revealed a small left paracentral disc protrusion at L4-L5 and a moderate central disc protrusion at L5-S1 slightly more pronounced on the right.

Despite chiropractic and physiotherapy treatment, the worker continued to experience back pain. On October 13, 1999, he was assessed by a WCB medical advisor who felt that the worker may have a resolving L5-S1 right sided disc herniation. She recommended referral to a physiatrist for epidural steroid injections. She also thought that the worker’s sleep pattern should be treated. She cautioned however that the worker had 5/5 Waddell signs and an abnormal illness behaviour that should be monitored.

The worker was seen by the physiatrist on October 21, 1999. It was his impression that the worker’s symptoms and physical findings could be related to the lumbosacral disc herniation noted on the CT scan. He did however concur that there were other non-structural findings that might improve once the radicular symptoms did. He performed a caudal epidural corticosteroid injection which did not provide the worker with much relief. He therefore recommended a surgical opinion.

On November 25, 1999 a rehabilitation specialist attended the worker’s job site and noted that the postural component of the worker’s job did not respect his compensable restrictions of no lifting weights in excess of 30 pounds, no work below the knees and no excessive bending or twisting.

The worker was seen by a WCB psychological advisor on January 24, 2000. The report of this interview is dated January 26, 2000. It outlines the worker’s history, his daily routine as well as his psychiatric testing results. The report makes specific reference to the fact that the worker had poor sleep and a relatively low level of activity (which was consistent with his pre-accident level) with the exception of his inability to go snowmobiling. The testing noted that the worker had a tendency to catastrophize or be overly sensitive or responsive to pain along with a relatively high level of activity when in pain. However, there was no evidence of symptom exaggeration. The worker was also interviewed by the pain management unit at the WCB on January 31, 2000. Its findings are outlined in its report of February 2, 2000.

The worker saw an orthopaedic surgeon on March 6, 2000. It was his opinion that the worker was suffering from back pain that was probably mechanical in nature. There was some radicular element to it but there was no significant disc herniation present that would be surgically amenable. An MRI examination was suggested to rule out other occult causes for the worker’s postural pain. It was performed on May 8, 2000. The orthopaedic specialist noted that the MRI results only showed a bit of a mild disc herniation at L4-5 that was left sided, whereas the worker’s complaints were right sided. He thought that the worker’s main complaints were mechanical in nature and suggested a re-conditioning or work hardening program.

A Functional Capacity Evaluation (“FCE”) was done on July 31, 2000 to determine the worker’s functional capabilities. The FCE results were considered valid as the worker put in a full voluntary effort in performing the tests. The functional abilities evaluator administering the various tests noted that the worker did not have a very good perception of his symptoms and that he had a degree of de-conditioning. He noted that the worker’s lumbar range of movement was limited and that he only demonstrated the ability to lift at a light to sedentary rate of work.

In early October 2000, a physiotherapist saw the worker in preparation for a re-conditioning program. In the initial assessment report, the worker’s main physical problems were listed as central low back pain radiating into the right buttock and right testicle. Pain was reportedly aggravated by forward bending, prolonged sitting greater than 45 minutes, walking greater than 20 minutes and carrying items over 25 pounds. He reported difficulty with adopting and maintaining positions with his lumbar spine. The worker reported that there was less shooting pain in his right leg, however there was an increase in burning discomfort in his low back. He rated his pain level at 7/10 on average. In a conversation with the WCB medical advisor, the physiotherapist also mentioned the worker’s pain behaviour and opined that it was unlikely that the worker would be ready to return to work at the end of the six week re-conditioning program. At the recommendation of the physiotherapist, the worker was assessed by a psychologist. The assessment revealed some sleep disturbance and dysphoric mood in addition to reported anger associated with adjustment to his physical status.

Surveillance videotape was taken of the worker’s activities on October 7, 8 and 9, 2000. This surveillance was reviewed by a WCB medical advisor on October 25, 2000. She noted that the worker was seen riding a snowmobile on the video tape and was exhibiting movements such as standing, squatting, leaning, pulling, etc. without obvious difficulty. When compared to the findings at the conditioning program in October 2000, it was the medical advisor’s opinion that the worker’s actual functional capabilities were far greater than his reported and formally tested abilities. She felt the worker should be able to return to his regular duties as of October 8, 2000. She also noted that the psychological assessment that took place on September 6, 2000 revealed no acute psychological issues which would require treatment.

The treating physician disagreed with this assessment. He reviewed the surveillance and the WCB medical advisor’s report. He also questioned the worker with respect to some of the activities recorded on surveillance. He noted that the video surveillance showed the worker crouching quite cautiously and towards the end of the surveillance walking with a decidedly unusual gait which was not normal and was quite consistent with somebody suffering from back pain. He conceded that the video did show the worker engaged in activity that exceeded that which had been displayed and reported previously but added that he had advised the worker to engage in activities as tolerated. A later report notes that he did in fact tell the worker that he could try snowmobiling but that if it hurt, to stop.

He noted that the worker’s current diagnosis was back pain associated with a discopathy. He thought that the worker was still in pain and discomfort and had referred him to an orthopaedic specialist for assessment. He noted that due to the worker’s condition he was unable to do the heavy lifting required in his job as a heavy duty mechanic.

At the hearing, the worker testified that that was the last time he ever went snowmobiling. He said that the next day he was so sore that he spent the entire day in bed. He noted that the surveillance the day after showed him hobbling down the street because he could barely walk.

The worker was seen by the orthopaedic specialist on September 26, 2001. The orthopaedic specialist thought that the worker was suffering from mechanical lumbar back pain, probably on the basis of lumbar disc injury with possible strain to the posterior facets. On the basis of this presentation he recommended a series of bilateral facet joint injections at the L5-S1 and L4-5. He noted that after the bilateral facet joint injection at the L5-S1 that the worker received 50% improvement in his pain relief in his back but still had pain down his right leg and his right foot went numb; after bilateral facet injections at the L4-5, he felt 55 to 60% better. The orthopaedic specialist was uncertain whether the facet joints were the only or main cause of the worker’s pain but commented that with further injections or a facet joint rhizolysis he may recover enough to allow a return to his previous physical level of activity. He added that it was his opinion that at that time, the worker’s physical limitations were lack of endurance, chronic pain and restricted lumbar flexibility which would have interfered with his abilities to perform his duties as a heavy duty mechanic. He commented that he had no information to suggest that there were other injuries or pre-existing conditions that would indicate that the July 9, 1999 injury was not the cause of the worker’s ongoing mechanical lumbar back pain.

The worker was referred to a pain clinic for facet joint blocks which were performed on January 27, 2003. The facet joint blocks provided the worker with great relief. Given the positive results, the worker underwent a rhizotomy on March 10, 2003 at the L4-5 and L5-S1 levels on the right side. The specialist was of the opinion that the worker’s facet joints were the cause of his pain and this was consistent with the mechanism of injury. At the hearing the worker testified that given the success of the rhizotomy, he attends for one every four to five months. He explained that the rhizotomies make the pain manageable to the point that he could increase his activity level to the point that he was able to begin looking for sedentary employment shortly thereafter.

On June 2, 2005 an orthopaedic consultant to Review Office opined that the diagnosis of the worker’s compensable injury was a possible disc injury L4-L5 without neurological involvement. The consultant noted that the worker had a history of back problems prior to the July 6, 1999 compensable injury and thought it most unusual to not have recovered within six years given the previous reported findings subsequent to the compensable injury.

Given the medical discord relating to the worker’s condition and his ability to return to work by October 8, 2000, Review Office convened a Medical Review Panel (“MRP”). The MRP was not unanimous in its conclusion. In its final report dated May 1, 2006, the majority of the panel found that the most probable diagnosis of the worker’s back injury on July 6, 1999 was a simple contusion of the low back resulting in a strain of the low back. The majority also found that the worker had recovered from the effects of his workplace injury by October 8, 2000. No rationale was provided for this opinion. The dissenting doctor opined that the worker most likely suffered a combined disc and facet joint injury at the L4-5 and L5-S1 levels. This opinion was based on a history of a significant axial load to the lumbar region, possibly involving rotational and flexion or extension forces as well which would have been sufficient to cause significant disc and/or facet injury. He did not think that the worker had recovered by October 8, 2000, noting that there was diagnostic evidence of persisting disc herniations at the L4-5 and L5-S1 as late as May 30, 2001. He added that although there was some variability of clinical presentation of different occasions, this type of presentation was consistent with underlying disc and facet joint disease in an individual with a prolonged disability. Given this evidence as well as the video surveillance and other non compensable issues, the doctor thought that the worker was only capable of sedentary activity. He thought that the since his compensable injury the worker had made a partial but not a complete recovery. He thought that the worker would likely have continued back symptoms under a variety of circumstances for the foreseeable future. Alternately, he would likely have days during which he could function at the level he did during the surveillance video capturing his snowmobiling. At the time of the MRP, he thought that the worker would probably be capable of sedentary and light physical activity on a sustained basis and heavier intermittent activity. He added that he was probably not capable of his previous level of function and that function might improve or deteriorate over the next several years. Given this, he thought the worker should only work at a light physical level; these restrictions should however be reviewed within two years.

Worker’s Position

The worker says his appeal should be accepted as he was still not recovered from his compensable injury by October 8, 2000 and was unable to return to his pre-accident employment.

Analysis

To accept the worker’s appeal we must find on a balance of probabilities that the worker’s ongoing back symptoms after October 8, 2000 were causally related to his July 9, 1999 compensable injury and that he suffered a loss of earning capacity as a result of this compensable injury. We are able to make those findings.

The evidence before us is that the worker suffered a compensable injury to his lower back on July 9, 1999. Though the majority of the MRP opined that this compensable injury was a simple contusion we find that the medical evidence on file does not support this opinion. The initial diagnosis of the worker’s low back condition was a disc herniation. More recent medical testing has opined that this diagnosis was incomplete and that the full diagnosis was a disc herniation and a facet joint sprain; this later diagnosis was confirmed by the facet joint blocks and outcomes of the rhizotomies. We accept these two diagnoses as the compensable injury given the continuity of signs and symptoms displayed by the worker as well as the medical opinions that this diagnosis is consistent with the worker’s mechanism of injury.

As of October 8, 2000 we do not see any evidence that either of these diagnoses had resolved or that the worker had returned to his pre-accident status. While the video surveillance did show the worker snowmobiling, this was done with the prior authorization of his family physician. The worker also testified that this was the last time he went snowmobiling because of the pain it caused him. The video surveillance certainly shows very little to no activity the day following the snowmobiling and would appear to corroborate the worker’s evidence to some degree. The minority opinion of the MRP does comment as well that with the facet joint condition, symptoms can wax and wane. The panel notes that this would preclude the worker from performing his job duties as a heavy duty mechanic.