WORKPLACE SAFETY AND INSURANCE APPEALS TRIBUNAL DECISION NO. 2314/10

Transcription

1 WORKPLACE SAFETY AND INSURANCE APPEALS TRIBUNAL DECISION NO. 2314/10 BEFORE: J.G. Bigras: Vice-Chair HEARING: November 17, 2010 at London Oral Post-hearing activity completed on December 24, 2010 DATE OF DECISION: May 12, 2011 NEUTRAL CITATION: 2011 ONWSIAT 1154 DECISION UNDER APPEAL: WSIB Appeals Resolution Officer B. Howarth decision dated September 3, 2009 APPEARANCES: For the worker: For the employer: Interpreter: S.R. Yormak, Lawyer Did not participate C. Vinuca, Italian Workplace Safety and Insurance Appeals Tribunal Tribunal d appel de la sécurité professionnelle et de l assurance contre les accidents du travail 505 University Avenue 7 th Floor 505, avenue University, 7 e étage Toronto ON M5G 2P2 Toronto ON M5G 2P2

2 Decision No. 2314/10 REASONS (i) Introduction to the appeal proceedings [1] The worker appeals a decision of the Appeals Resolution Officer (ARO), which concluded that the worker was not entitled to compensation benefits for low back surgery on January 31, Entitlement is sought in regard to a workplace accident on July 22, The ARO rendered a decision following an oral hearing. (ii) Issue [2] The only issue before me is entitlement to benefits for lumbar back surgery on January 31, [3] The appeal is allowed for the reasons set out below. (iii) Background [4] The now 59-year-old worker was a boilermaker/welder with the accident employer. On July 22, 1993, the worker slipped and fell down some stairs while in the course of employment. He suffered shoulder, neck and low back injuries. Attempts at vocational rehabilitation were not successful. The worker became entitled to a 29% Non-Economic Loss (NEL) benefits for permanent disability due to the cervical and lumbar spine conditions. He was also awarded Future Economic Loss (FEL) benefits representing the difference between pre-injury earnings and the earnings he is deemed by the Board to be able to earn after the injury. [5] On January 31, 2007, the worker underwent a surgical procedure diagnosed as a posterior lumbar interbody fusion with decompression at L3-L4. The Board found that the surgery was required due to spinal stenosis, a condition which did not result from the compensable injury. [6] The worker appeals. (iv) Law and policy [7] Since the worker s injury occurred in 1993, the pre-1997 Worker s Compensation Act is applicable to this appeal. All statutory references in this decision are to the pre-1997 Act, as amended, unless otherwise stated. The hearing of the appeal commenced after January 1, 1998; therefore, certain provisions of the Workplace Safety and Insurance Act, 1997 (the WSIA ) also apply to the appeal. [8] Specifically, sections 4 and 37 of the pre-1997 Act govern the worker s entitlement in this case. [9] Pursuant to section 126 of the WSIA, the Board stated that the following policy packages, Revision #8, would apply to the subject matter of this appeal: Policy packages: 31; 38; 300

3 Page: 2 Decision No. 2314/10 [10] I have considered these policies as necessary in deciding the issues in this appeal, in particular: Operational Policy Manual (OPM) Document No , Recurrences ; OPM Document No , Resulting from Work-Related Disability. (v) The worker s evidence [11] The worker gave evidence that he was coming down a stairway when he slipped on a piece of plastic danger tape halfway down the ramp. He does not remember clearly what occurred but stated that he tumbled down the four or five remaining steps and landed at the bottom. He was holding his welding tools. His helmet was knocked off is head. [12] The worker stated that he was dazed and disoriented. His left shoulder was bleeding and he remembers having red spots on his knees, back, arms. [13] The worker saw the company nurse who told him he would be okay in a few days. He showed up for work the next day but was too sore to work and was sent home for another day by the foreman. He continued to work. Since no improvement was experienced, the worker left work on August 20, 1993, and visited his family physician for the first time on August 31, [14] The worker stated that he continued to experience pain in the left shoulder down the left arm and in the lower back, radiating into his leg. He stated that he was awarded Canada Pension Plan (CPP) disability benefits soon afterwards. (The record shows that these benefits were granted starting in April 1996.) [15] The worker denies any intervening events or motor vehicle accidents. [16] Due to his disability, the worker could not return to his trade of boilermaker. He was assessed a combined 29% NEL award for the cervical spine (13%) and lumbar spine (18%). A Suitable Employment or Business (SEB) of security guard was determined by the Board. The worker started vocational rehabilitation with a course in English Second Language, but dropped out due to reported pain. He did not return to work and was assessed a FEL award representing the difference between his pre-injury earnings and his projected earnings as a security guard. [17] The worker gave evidence that he experienced severe pain which was only temporarily alleviated by the surgery in He only performs minor tasks around his home and only 15-to-20-minute light activities outside the house. His social activities are limited to a half-hour coffee breaks with friends in the afternoon. Some of his medications make him dizzy. (vi) The medical history [18] The record shows that, on the day of the injury, July 22, 1993, the worker was seen by the company nurse. He first saw family physician Dr. L.P.C. LiChong on August 31, 1993, complaining of neck, shoulder, arms, low back and leg pain. On September 7, 1993, the worker began an 18-treatment course of physiotherapy focused mainly on the left shoulder, which was seen as his main problem. A shoulder injection was performed in September 1993.

4 Page: 3 Decision No. 2314/10 [19] The worker continued to work until September 20, [20] Dr. LiChong reported that, on December 22, 1993, the worker woke up with pain in the left neck area. Neck muscles were tender and lateral movements were restricted at 30 degrees. [21] On December 29, 1993, the worker was seen by orthopaedic surgeon Dr. P. Mehta. The specialist s diagnosis was reported as follows: Examination reveals an anxious patient who seems to have a fine tremor in his hands. Examination of the cervical spine reveals he does have a really fairly good range of cervical spine movements. However, he remains tender in the lower cervical spine muscles and the left trapezius muscles as well. Neurologically, the cranials are normal. The upper extremities show he has normal motor function and no sensory changes. Reflexes are equal and symmetrical. The shoulders show that he has a good range of movements but the shoulder movements seem to produce pain in the left trapezius area. He is tender in the lower lumbar spine. There is a good range of movements. Straight leg raising is 90 on either side with no deficit. X-rays of the lumbar spine show that he has L5-S1 old narrowing disc otherwise the lumbar spine is normal. Cervical spine does show that he has degenerative changes at the C5-6 level which are early with some foraminal narrowing. I really feel this patient s symptoms are from a flexion extension injury to his cervical spine area primarily and to a lesser extent his lumbar spine. He has ongoing symptoms. He has had all the usual modalities of treatment and the only thing I can think of at the moment is that he has got anxiety which may be causing some endogenous depression secondary to his anxiety and I thought the thing would be to try some amitriptyline and ask him to continue his exercises and I will review him in four weeks time. The other thing I think one should do here is get a neurological opinion to see if there is any cervical nerve root entrapment though I really don t think so but it would be worthwhile getting him to see a neurologist. If his symptoms persist he will be a candidate for the W.C.B. Evaluation Center in London as I really don t think there is any other treatment that is likely to be of avail here. [22] Electrophysiological tests by neurologist Dr. S.R. Burton on March 30, 1994, showed no abnormalities other than mild carpal tunnel syndrome. Dr. Burton reported that the worker was complaining of pain in the back, neck and shoulders. The most pressing symptom was pain in the neck and shoulder. [23] A Functional Abilities Evaluation (FAE) was conducted at the London Regional Evaluation Centre on June 30, Therapists noted generalized weakness of the left shoulder and a decrease of the lumbar spine flexion and complaints of pain in the lumbar area. Neurological examination of lower extremity reflex, power and sensation were reported as normal. The worker was diagnosed as ready to return to work within his physical limitations. [24] An examination of the worker was conducted on March 2, 1995, by neurosurgeon Dr. H.W.K. Barr. His diagnosis was as follows: 1. Possible C5-6 left sided disc protrusion +/- osteophyte compression of the left C6 nerve root. 2. Rotator cuff syndrome left.

5 Page: 4 Decision No. 2314/10 3. Mechanical low back pain due to degenerative intervertebral discs L5-S1 level and facet joint arthritic changes the symptoms which seem to have been precipitated by the trauma. [25] Dr. Barr s report of lumbar assessment was as follows: Lumbar Assessment he has a normal lumbar external posture, excellent paravertebral muscle tone and bulk. Range of Motion he has reduced range of motion of his lower back to 30º of flexion, 20º of extension and approximately 10º of tilting. These manouevers resulted in back pain only, not leg pain. Straight leg raising was 90º bilaterally and reverse straight leg raising was painful on the right, in the low back areas. [26] At that time, the focus of the medical treatment evolved around his neck and left shoulder. However, on April 26, 1995, Dr. LiChong diagnosed generally worsening pain in [the worker s] neck, left shoulder and lumbar area. [27] However, CT Scan examination of April 30, 1996 resulted in the following report by radiologist Dr. G.E. Blundell: C.T. LUMBAR SPINE: INDICATION: TECHNIQUE: FINDINGS: Backache. Numbness in the right leg. Serial angled 5.0 mm slices with 2.0 mm of overlap of the lower three disc spaces. Plain films demonstrate the presence of five free lumbar vertebrae. The L3-4 disc demonstrates a mild annular bulge. Mild degenerative change is present in the facet joints at this level. The L4-5 disc demonstrates a moderate annular bulge. Moderate degenerative changes are present in the facet joints. The L5-S1 disc demonstrates a mild central bulge. The facet joints at this level are normal in appearance. IMPRESSION: Degenerative changes at the facet joints at L3-4 and L4-5. Annular discs at L3-4 and L4-5 which impinge on the undersurface of the dural sheath. No evidence of focal disc herniation is seen. [28] Following a CT Scan on February 22, 1999, radiologist Dr. P. Greenhow issued he following report: LUMBAR SPINE AP, lateral and oblique views. There is quite advanced degenerative disc disease with disc narrowing, sclerosis and osteophyte formation at the L5 S1 level. There is some arthritic change in the lower facet joints most marked at L3-4 and with moderate changes at L4-5 and on the right at L5 S1. Apart from L5 S1 the remaining disc spaces appear quite well preserved although there are minor osteophytes at the L3-4 level. No evidence for fracture, subluxation or destructive bone change and the S1 joints appear normal.

6 Page: 5 Decision No. 2314/10 Conclusion: Degenerative disc disease maximal at L5 S1 where there is considerable disc narrowing suspected. Some arthritis in the lower fact joints. The changes have advanced slightly since the previous of March 1, [29] On June 29, 1999, Dr. Barr viewed the reports of recent x-rays and scan and examined the worker who was complaining of the following: Present Chief Complaints 1. A mid line lower back pain, at the belt line and slightly below. 2. Right iliac crest area pain appears to be his major complaint, this is aggravated by standing and walking, etc. 3. Right leg discomfort is described as being present in the right buttock, posterolateral thigh to his knee and occasionally on walking, the pain may spread to the lateral aspect of his right calf to just above his ankle. He notices the odd feeling of numbness affecting his right foot in the area of the right great toe and therefore he could have an L5 root compression. He does not describe weakness of his right leg. [30] Dr. Barr s diagnosis was as follows: Diagnosis 1. Lumbar degenerative spondylosis resulting in ongoing lower back pain and particularly right iliac crest pain, this may well be arising from the facet joint arthritic changes seen on the CT scan. 2. Right sciatica of an L5 root type, but I do not see a definite disc herniation or compression of the L5 nerve root in the lateral recess, to account for this right leg radicular pain syndrome. [31] Dr. Barr ordered MRI examination which was conducted at the London Health Sciences Centre on October 24, The findings of radiologist Dr. D. Lee for the lumbar spine were as follows: In the lumbar spine, there is loss of disc signal at the L3/4 through L5/S1 level; loss of disc height is present at both L4/5 and L5/S1. The L1/2 level is unremarkable in terms of disc and soft tissues. Bilateral facet changes of mild degree are noted. The intervertebral foramen is not however encroached upon. At L2/3, there is mild disc bulging into the inferior foramen bilaterally. This does not affect exiting or traversing roots. Again at this level, mild facet changes are noted. At L3/4, there is foraminal narrowing bilaterally due to a combination of bilateral facet changes, as well as disc bulging into the inferior foramen. Slightly more left sided ligamentous change is present around the facet joints and there is effacement of fat posterior to the exiting left L3 ganglion; not definite root compression is however seen. At this level as well, there is severe spinal stenosis, due to a combination of bilateral ligamentous thickening, and disc, with a small central disc as well. The epidural fat is inwardly displaced by ligamentous thickening, which further contributes to the spinal stenosis. Maximal level the spinal stenosis is actually just below the plane of the L3/4 disc where the ligamentous thickening is largest. At L4/5, there is disc bulging into the inferior intervertebral foramen bilaterally. This does not affect the exiting roots. Again at this level bilateral facet changes and some ligamentous enlargement is seen. However, epidural fat is seen around the root in the foramen on each side.

7 Page: 6 Decision No. 2314/10 At L5/S1 bilateral facet changes are seen, and, apart from some osteophytic changes posterolaterally around the intervertebral disc on each side, and, some central disc which lies in epidural fat and does not affect the dural tubes at all, no abnormalities are seen. Pre and paravertebral soft tissues are unremarkable. There is some increase in fat content in the S1 vertebral body and probably also in the iliac bones. No marrow abnormalities are otherwise seen. End plate changes are noted as the L5/S1 level. IMPRESSION: Severe spinal stenosis at L3/4; mild spinal stenosis at L4/5. At L3/4, there is slightly more right sided lateral recess narrowing due to posterolateral disc and osteophytic change and the ligamentous thickening around the facet joint. This could potentially explain left L4 radiculopathy. Some lateral recess narrowing is also present at L4/5, which could explain the patient s right sided L5 radiculopathy. [32] In a report to the worker dated October 28, 1999, Dr. Barr explained the worker s condition and mentioned the possibility of surgery, a procedure he would not recommend at that time. From the standpoint of your right leg pain which could be arising from one of the two lower vertebral segments of your lumbar spine, L4-5 or L5-S1 levels, we do not see a definite disc herniation or obvious compression of the nerve roots at this level. The one level above however, the L3-4 level, does reveal a rather severe lumbar central spinal canal stenosis. This is a narrowing of the canal which contains the nerves of the lower back, in a dural tube, before they exit to enter one s legs. The condition of the lumbar spinal stenosis is in part due to bony over growth of arthritis, as well as thickening of the ligaments. The usual symptoms of lumbar spinal stenosis are those of the development on walking of tingling and numbness in a patient s legs and a feeling eventually of impending weakness. When the patient stops walking, stands or sits, within 4 to 5 minutes, the symptoms usually disappear and they can start walking once again. [...] My problem in your case is knowing whether you would or would not notice an improvement of your complaint of right leg pain, conceivably the nerve travelling through your leg could be compressed in this area of lumbar stenosis, but I would have preferred to have seen a disc herniation at one of the two lower levels of your spinal column to account for your pain syndrome. I cannot strongly recommend therefore that you undergo the operative procedure of a lumbar laminectomy, but this is a treatment option, based on the result of your MRI. [33] Further radiological studies at the Lambton Hospital on April 19, 2002, confirmed the presence of a segmental spinal stenosis at L3-4, as well as a prominent annular bulge at L4-5. [34] Following further MRI examination at the London Health Centre on March 12, 2003, orthopaedist Dr. H. Bailey stated that the worker had evidence of spinal stenosis at L3-4 and L4-5 causing claudication of the right leg. Dr. Bailey mentioned the possibility of decompression surgery without any guarantee of relief. [35] After consulting orthopaedic surgeon Dr. K.R. Gurr on July 22, 2003, Depo-Medrol spinal injection was performed by anaesthesist Dr. M. Bastorovich on November 26, A second injection took place on March 5, 2004.

8 Page: 7 Decision No. 2314/10 [36] Further MRI examination on December 22, 2005 resulted in a report from radiologist Dr. L.A. Potts which stated as follows: IMPRESSION: There is a severe spinal stenosis evident at L3-4 due to a combination of degenerative discs and facet changes with associated hypertrophy of the ligamentum flavum. When comparison is made with the previous CT of the lumbar spine obtained in 2002, the stenosis at this level has progressed in the interval. Annular disc bulging is seen at L2-3, and L4-5. The bulging discs are producing mild deformity of the thecal sac. At L4-5, the bulging is skewed to the right and is seen to lie immediately adjacent to the right L5 nerve root as it exits the thecal sac, however definite displacement has not been identified. [37] On January 31, 2007, Dr. Gurr performed surgery to repair a central stenosis condition at L3-4 by decompression of the disc space. [38] The worker continued to complain of ongoing pain in the lumbar back and legs. Treatment continued for osteoarthritis. (vii) Analysis [39] The worker claims entitlement to benefits for the condition which resulted in surgery on January 31, According to the medical record, surgery was required to correct a spinal stenosis condition at L3-4. [40] According to a WSIAT Discussion Paper on Back Pain, authored by orthopaedic surgeon Dr. W.R. Harris and neurosurgeon Dr. J.F.R. Fleming, spinal stenosis is one of the three main conditions in which aging may cause symptoms. Spinal stenosis is described as follows: In spinal stenosis, the gradual formation of bony outgrowths narrows the spinal canal and the openings through which the spinal nerves emerge. This condition is not caused by trauma. In people who have a small diameter spinal canal to begin with, the nerve roots are more vulnerable to compression. This narrowing of the spinal canal produces numbness and weakness ( my legs feel rubbery ) in the legs, typically brought on by walking and disappearing slowly with rest. If the symptoms are severe and disabling, surgery to decompress the affected nerve roots may be required. [41] In this case, surgery was performed on January 31, The issue is whether or not a causal relationship exists between the worker s accident on July 22, 1993, and the stenosis at the L3-4 level of the spine. [42] Board OPM Document No , Recurrences, states that a worker is entitled to benefits for a recurrence of a work-related injury. The policy states that a recurrence may result from an insignificant new accident, or may arise when there is no new accident. To identify a recurrence, decision-makers must confirm that there is clinical compatibility between the original injury or disease and the current condition, or a combination of clinical compatibility and continuity. [43] As an initial consideration on the issue, I note that there is no evidence in this case showing that a second accident occurred to cause the worker s recurrence.

9 Page: 8 Decision No. 2314/10 [44] Turning to the issue of continuity, I note that, according to Dr. Mehta, the first x-ray examination following the accident, on March 30, 1994, showed spinal narrowing at L5-SI. Otherwise the lumbar spine was normal. [45] Subsequent medical attention remained focused mainly on the worker s C-spine and shoulder. However, in March 1995, an MRI showed degenerative intervertebral discs at L4-5 precipitated by trauma, but a normal spine at other levels. [46] The first mention of the L3-4 level of the spine was in a CT report dated April 30, 1996, when it was diagnosed that the annular discs at L3-4 and L4-5 impinged on the undersurface of the dural sheet. Further radiological studies on February 22, 1999 showed marked arthritic changes at L3-4 and moderate changes at L4-5. [47] On October 25, 1999, MRI examination revealed severe spinal stenosis at L3-4 and mild stenosis at L4-5. [48] I have considered the Discusion Paper s statement that a major fall could cause an aggravation of stenosis, within a year after the occurrence. However, my review of the medical history gives reason to Mr. Yormak s argument that there was a gap in the radiological studies during the first three years and that likely explains why the condition was not diagnosed earlier. In fact, after x-ray examination of September 1, 1993, no radiological studies were conducted of the lumbar back until a CT Scan on April 30, At that time, a problem was diagnosed with impingement of the dural sheath at L3-4 and L4-5. The neck problem had continued to be of focal concern at that time. However, by February 22, 1999, minor osteophytes had formed at L3-4. Osteophytes are bony outgrowths which are mentioned in the WSIAT Discussion Paper as causes of narrowing of the spinal canal known as stenosis. [49] Turning to the compatibility issue, I first note that the nature of the injury as originally diagnosed included a neck problem, a left shoulder strain and a lumbar strain at L4-5. The worker has been entitled to a NEL award for these conditions following an assessment on October 29, [50] Also on the issue of compatibility, I note that the WSIAT Discussion Paper on Back Pain mentioned earlier, states that spinal stenosis is not likely to result from trauma, such as a strain due to heavy lifting. However, the paper qualifies this statement by adding that a causal relationship cannot be ruled out given that it is possible when the trauma takes the form of a fall. This is what occurred in this case as the worker slipped in a stairway and tumbled down four or five steps. [51] The injury was not believed to have been serious and the worker continued to work for a month afterwards. However, it is not impossible to believe that the accident triggered a degenerative process in the lumbar spine. [52] Medical attention was first turned to the neck and the left shoulder. X-ray examination was first conducted on September 1, There does not seem to have been any other such studies of the lumbar back until a CT Scan of the lumbar spine was conducted on April 30, The neck remained a problem for which the worker is now entitled to benefits and the shoulder appears to have recovered completely.

10 Page: 9 Decision No. 2314/10 [53] However, the worker kept complaining of low back pain. On July 25, 1993, Dr. Mehta revealed an old narrowing of the disc at L5-SI. It is evident that a degenerative process had been triggered by March 2, 1995, when Dr. Barr diagnosed mechanical low back pain along with degenerative discs at that same level. [54] A CT Scan on April 30, 1996 showed degenerative changes at L3-4 and L4-5. Annular discs impinged on the dural sheet on these two sites. [55] On this issue, I note that, in his report dated October 26, 1999, Dr. Barr explained that the worker had severe lumbar spinal stenosis at L3-4. At that time, Dr. Barr also stated that spinal stenosis is a narrowing of the canal which contains the nerves of the lower back in a dural tube, before they exit into one s legs. The condition of lumbar spinal stenosis is in part due to bony outgrowth of arthritis, as well as thickening of the ligaments. [56] This is also the view stated in the Discussion Paper. In answer to the question whether or not an injury can precipitate aging change, the authors state that this may occur from a severe injury such as a fall (as opposed to a lifting strain). The narrowing of a single disc can result from a bony outgrowth at the adjacent vertebral margins. [57] My finding that the worker s condition was due to the aggravation of the spine, triggered by the accident, is contrary to the view of Board Physician Dr. L. Monette who stated on December 19, 2007 that his review of the medical file did not include evidence of compatibility for aggravation of the back condition. [58] However, Dr. K.R. Gurr, the surgeon who performed the surgery at the L3-4 level of the spine on January 31, 2007, stated as follows on May 29, 2007: With respect to the cause of this injury, [the worker s] symptoms came on as a direct result of his work-related injury. He may have had a previously underlying problem; however, this was aggravated and made symptomatic by his work injury. [59] I accept the evidence of the treating professional in this case. [60] Therefore, on the evidence, I conclude that the natural progression of the disc disease which resulted in spinal stenosis at the L3-4 disc was likely triggered by the accident on July 22, Therefore, the worker is entitled to benefits for the spinal stenosis at L3-4, including the benefits for the surgery of January 31, 2007.

11 Page: 10 Decision No. 2314/10 DISPOSITION [61] The appeal is allowed. DATED: May 12, 2011 SIGNED: J.G. Bigras