Decision #119/08 - Type: Workers Compensation
Preamble
On January 13, 2004, the worker filed a claim with the Workers Compensation Board (“WCB”) for a right hip injury that occurred in the workplace on December 31, 2003. The claim for compensation was accepted based on a strain/sprain type injury and the worker was paid wage loss benefits to August 23, 2004 when it was determined that the worker’s ongoing back and right hip difficulties were not related to the compensable injury. The decision was confirmed by Review Office on September 10, 2004 and July 17, 2006. By further Review Office decision dated March 27, 2008, benefits were extended to October 12, 2004. The worker disagreed with Review Office’s decision and an application to appeal was filed with the Appeal Commission and a hearing was held on August 7, 2008.Issue
Whether or not the worker is entitled to wage loss benefits beyond October 12, 2004.Decision
That the worker is not entitled to wage loss benefits beyond October 12, 2004.Decision: Unanimous
Background
In her application for compensation benefits dated January 13, 2004, the worker reported that she experienced right hip pain which she attributed to “slipping at lot on the ice”, while loading and unloading a trailer on December 31, 2003. The worker also reported that she had been taking medication for osteoporosis for the past year and was born with spina bifida.
Medical information revealed that the worker attended for medical treatment on January 12, 2004 and was diagnosed with right hip sciatica and severe lumbar pain by the treating physician.
The worker had a CT scan of the lumbar spine from L2 to L5-S1 on February 12, 2004. The radiological report stated, “There likely has been previous surgery of the lumbar spine with perhaps fusion of the L2-L5 vertebral bodies. There is degenerative narrowing at the L5-S1 interspace with anterior subluxation of the 5 lumbar vertebra on the sacrum. A left sided pars interarticularis defect is present. There is likely bony narrowing of the right-sided L5-S1 intervertebral foramen.”
At the request of primary adjudication, the file information was reviewed by a WCB medical advisor on April 29, 2004. He stated, “At this point, strain plus a likely aggravated pre-ex…radicular symptoms are likely related to the pre-ex narrowing of the sacrum. There is a pars defect on the CT which is also likely pre-ex but may be new and could contribute to her symptoms – she should have bone scan to clarify…”.
On March 17, 2004, the worker was assessed by a physiotherapist. Subjective complaints consisted of low back pain radiating down right leg to ankle, numbness and tingling, back spasm and unable to sit for long periods of time. The diagnosis rendered was L5-S1 nerve entrapment. It was anticipated that the worker could return to work on May 10, 2004 with restrictions of no lifting and no sitting for long periods of time.
On June 2, 2004 a bone scan revealed the following findings: “…Moderately intense focal uptake is seen in the lower lumbar spine at approximately L4-L5 posteriorly on the left. It is uncertain whether this represents arthritic change or a pars defect. Mild uptake is seen at L5-S1 on the right consistent with arthritic change.”
An examination by a WCB medical advisor was held on July 5, 2004. The worker indicated that she had back pain on and off for most of her life but did not have any radicular symptoms in the past. The examination revealed evidence of an L5 nerve root irritation on the right side. It was felt from a review of the worker’s history and CT scan that this was likely related to bony narrowing of the L5-S1 foramen which was due to her pre-existing surgery. The medical advisor further stated, “The mechanism of injury that she describes is non-specific and would not be an obvious cause to radicular symptoms. It is possible that her described work place injury caused an aggravation of pre-existing back difficulties resulting in a nerve root irritation. However, her main difficulties are related to the bony narrowing of the foramen which would not have been caused by her work place injury but by her pre-existing surgery…my diagnosis would be an L5 radiculopathy resulting from an aggravation of pre-existing foraminal narrowing at L5-S1. I feel that further physiotherapy may be of benefit but, ultimately, she may require injections and possibly surgery to correct her pre-existing problem.”
In a decision dated August 16, 2004, the worker was advised that wage loss benefits would be issued to August 23, 2004 inclusive and final. The case manager referred to the WCB medical advisor’s opinion that her main difficulties were related to the bony narrowing of the foramen which would not have been caused by her workplace injury but by her pre-existing surgery. The worker disagreed with the decision and appealed to Review Office. In her submission dated August 18, 2004, the worker stated in part, “…my doctor [name] and I do not agree. This is the way my back developed from birth and I have not had any problems with my back until Dec 31 2003 when I slipped on the ice, which resulted in a slipped disc (L5). As a result, the sciatic nerve flared up around this disc and also the L1 and L2 discs…At this present time, the sciatic nerve flares up and I am unable to sit comfortably for any longer than 30-40 minutes, not able to lift anything greater than 25 lbs and no repetitive bending or twisting.”
Prior to considering the worker’s appeal, Review Office asked a WCB orthopaedic consultant to review the file and respond to specific questions. In a response dated August 31, 2004, he stated, “There was no specific injury described occurring on January 1, 2004, or for that matter on December 31, 2003. The claimant has extensive pre-existing multi-level degenerative disc disease, plus osteoarthritis of lumbar spine, giving rise to degenerative spinal stenosis plus the radicular-type symptoms involving the right leg. No specific injury described that would necessarily have aggravated the pre-existing spinal changes noted.”
On September 10, 2004, Review Office agreed with the case manager’s decision that the worker was not entitled to wage loss benefits beyond August 23, 2004. In reaching its decision, Review Office referred to various sections of The Workers Compensation Act (the “Act”) along with WCB policy 44.10.20.10 related to pre-existing conditions. After giving weight to the mechanism of injury, the opinion expressed by the WCB orthopaedic consultant and the fact that the worker denied any radicular symptoms in the past, Review Office was of the opinion that the worker had recovered from the workplace strain and possible aggravation of her pre-existing condition to the point that it no longer contributed to a material degree, to a loss of earning capacity beyond August 23, 2004.
Subsequent to Review Office’s decision, the worker submitted additional information from her treating physician for consideration. At the request of primary adjudication, the new medical information was reviewed by a WCB medical advisor on March 25, 2005. In a letter dated April 5, 2005, the worker was advised that the new information had been reviewed and the WCB was still of the opinion that she had recovered from her work injury and any possible aggravation of her pre-existing condition.
On August 22, 2005, the worker was advised by a WCB manager that there was no basis to convene a Medical Review Panel (“MRP”) as her treating physician did not provide a full statement of facts and reasons to support his medical conclusions.
In a report dated December 14, 2006, a neurologist reported that he could not find any evidence that the worker had a sciatic nerve problem. He stated her symptoms are in the supply of the right lateral femoral cutaneous nerve. This was a compressive phenomena of the nerve usually as it exits onto the thigh below the inguinal ligament. He stated that meralgia paresthetica is most likely due to compression of the right lateral femoral cutaneous nerve possibly from tight undergarments, hard objects like a low slung belt or objects in the hip pockets, tight clothes, hard materials such as denim creasing and pressing into the groin when worn tightly, etc. There was no evidence that any of the lumbar nerve roots were affected.
File information revealed that the worker was examined by a pain management specialist on April 3, 2007 with the chief complaint being low back pain. His diagnosis of the worker’s condition was piriformis syndrome. This diagnosis was also reported by the treating physiotherapist in a report dated April 9, 2007.
On May 1, 2007, a WCB case manager advised the worker that the above information was reviewed and the diagnosis of piriformis syndrome would not likely be the result of the mechanism of injury that occurred in 2003. It was still the WCB’s position that the worker had recovered from her original strain/sprain type of injury. The worker appealed this decision to Review Office on May 10, 2007.
In a June 7, 2007 report, the pain management specialist noted that the worker’s pain was localized to the back and buttock regions. He confirmed the diagnosis to be right sided piriformis syndrome.
On July 17, 2007, Review Office advised the worker that it had reviewed all of the evidence. In its opinion, the new diagnoses and symptoms of piriformis syndrome and right lateral femoral cutaneous nerve compression were not a result of the December 31, 2003 compensable injury. As a result, no change would be made to Review Office’s previous decision dated September 10, 2004.
In a report dated October 17, 2007, the pain management specialist recommended a diagnostic injection targeting the worker’s right piriformis muscle.
In a submission to Review Office dated January 25, 2008, a worker advisor contended that there was a causal relationship between the worker’s ongoing pain symptoms that continued to date and the workplace injury. In support of his position, he provided a report from the pain management specialist dated December 27, 2007. In part, the specialist outlined the view that the pain and numbness in the worker’s right leg along with right buttock pain began on the day of the slip while at work.
Prior to considering the appeal, Review Office requested and received medical information going back five years prior to the worker’s injury and consulted with a WCB senior medical advisor.
By memo dated February 20, 2008, the senior medical advisor opined that the most probable diagnosis associated with the compensable injury was one of sciatic radiculopathy, most probably coming from the L5 nerve root. Based on the evidence on file, the date of recovery would be between August 2004 and January 2007, a specific date not being readily apparent without more medical information.
In a further memo dated March 10, 2008, the senior medical advisor wrote that based on a review of the chart notes of the worker’s treating physician, the sciatic radiculopathy appeared to have resolved by October, 2004. At this point, the diagnosis seemed to change from sciatic radiculopathy to lumbar disc disease, and then again to sacroiliitis. No significant pain complaints nor objective findings were documented and the worker was probably back to her baseline, pre-compensable event status by this time.
In a decision dated March 27, 2008, Review Office determined that the worker was entitled to wage loss benefits from August 23, 2004 to October 12, 2004. In arriving at its decision, Review Office gave weight to the following:
· The CT scan findings of February 12, 2004;
· The opinion expressed by the WCB senior medical advisor on February 20, 2008 and March 10, 2008; and
· The neurologist’s opinion expressed in a report dated December 14, 2006.
On April 7, 2008, the worker advisor appealed Review Office’s decision to the Appeal Commission and an oral hearing was arranged.
Reasons
Worker’s submission:
The worker was represented by a worker advisor at the hearing. It was submitted on behalf of the worker that although she did have some back problems prior to her compensable injury of December 31, 2003, she was able to perform all of her job duties at that time. It was only after she suffered a workplace injury that she became disabled from continuing her work as a long distance truck driver. The WCB accepted her claim as an aggravation, with nerve root signs, resulting from the accident. Although the WCB has concluded that any aggravation would have dissipated effective October 2004, there is medical evidence to support a continuing aggravation and thus wage loss benefits should continue to be paid. Further, although the focus in this case has been on the condition of the worker’s lower back, there is also a problem with the right hip. It was noted that the worker had been complaining about the right hip since the very start of the claim, and at the present time, she is suffering from right piriformis syndrome, which is also work related. Overall, it was submitted that wage loss should be extended, further treatment provided, and assistance given with the goal of getting the worker back to work, hopefully to her former job in long distance truck driving.
Applicable Legislation:
The Appeal Commission and its panels are bound by the Act, regulations and policies of the Board of Directors. Under subsection 4(2) of the Act, a worker who is injured in an accident (as defined under the Act) is entitled to wage loss benefits for the loss of earning capacity resulting from the accident. Subsection 39(2) of the Act provides that the WCB will pay wage loss benefits until such a time as the worker’s loss of earning capacity ends, or the worker attains the age of 65 years.
WCB Policy 44.10.20.10 (the “Policy”) addresses the issue of pre-existing conditions when administering benefits. The Policy states:
The Workers Compensation Board of Manitoba will not provide benefits for disablement resulting solely from the effects of a worker’s pre-existing condition as a pre-existing condition is not “personal injury by accident arising out of and in the course of the employment.” The Workers Compensation Board is only responsible for personal injury as a result of accidents that are determined to be arising out of and in the course of employment.
The Policy further provides:
1. WAGE LOSS ELIGIBILITY
a. 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.
b. 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-exiting condition is not a compensable condition, the loss of earning capacity is not the responsibility of the WCB and benefits will not be paid.
Analysis:
To find that the worker is entitled to benefits after October 12, 2004, we must find on a balance of probabilities that after that date, the worker continued to suffer a loss of earning capacity as a result of her compensable injury. We are unable to make that finding. In the panel’s opinion, by October 12, 2004, the worker had recovered from the aggravation of her pre-existing condition and the present condition being complained of by her is not related to the injury she suffered in the course of her employment. The piriformis and current radiculopathy are conditions which developed subsequent to the resolution of the aggravation to the worker’s back.
In coming to our decision, the panel places reliance on the following evidence:
- In the initial months following the accident, the worker experienced a steady, albeit slow, improvement in her symptoms. The doctor’s progress report from an examination on March 11, 2004 reports that since being off work, the worker’s right sciatic pain had improved by fifty percent. Physiotherapy treatments aimed at spine achieved relief. On April 22, 2004, the physiotherapist reported that after 10 treatments, the L5/S1 nerve root entrapment was resolving. It was reported that the worker was “progressing very well with resolution of (right) leg pain and back pain only when she overdoes activity.”
- The WCB senior medical advisor conducted a very thorough and detailed review of the worker’s medical records. The results are summarized in his memorandum to file of February 20 and March 10, 2008. The panel accepts the senior medical advisor’s analysis and particularly, his observations that the treating physician’s clinical notes seem to indicate that by October 2004, the radiculopathy appeared to have resolved.
- In the report of the pain management specialist dated December 27, 2007, he comments on the July, 2004 examination by the WCB medical advisor and states: “I am uncertain why right piriformis muscle tenderness and hypertonicity were not detected clinically at that time.” In the panel’s opinion, this is consistent with the finding that the piriformis is a new condition which developed after the aggravation to the worker’s back had resolved;
- There are a number of other conditions affecting the worker’s spine, including pre-existing multi-level degenerative changes, a past history of spina bifida and osteoporosis. Any one of these conditions could be the cause of the piriformis syndrome and radiculopathy which the worker is now experiencing. As noted by the senior medical advisor: “The current diagnosis of piriformis syndrome, as well as meralgia paraesthetica, are conditions which have considerable controversy as to their etiology. The piriformis muscle is frequently affected by muscle imbalance, and would require only minimal perturbation in one’s environment to become symptomatic.”
For the reasons set out above, we find that by October 12, 2004, the worker recovered from the aggravation of her pre-existing condition to the point where it was no longer contributing, to a material degree, to her loss of earning capacity. Her pre-existing condition was not enhanced by the December 31, 2003 accident and we are of the opinion her current condition is related to non-compensable causes. As such, the worker is not entitled to wage loss benefits beyond October 21, 2004. The appeal is denied.
Panel Members
L. Choy, Presiding OfficerA. Finkel, Commissioner
M. Day, Commissioner
Recording Secretary, B. Kosc
L. Choy - Presiding Officer
Signed at Winnipeg this 12th day of September, 2008