The Appeal CommissionThe Workers Compensation Act of Manitoba

Background

On September 2, 1998 the worker tripped and fell. She filed a claim with the WCB and described the mechanism of injury as follows: “I was walking towards a desk & tripped on a plastic floor mat. Mat was not flat, but raised & I fell on the floor”. Injuries sustained by the worker were listed as a twisted back, sore right shoulder, neck and right knee.

The worker continued with her regular duties. She did however seek medical treatment.

She saw a chiropractor on September 3, 1998. She related her workplace accident and in particular that she had tripped over a mat and “fell hard hitting head, right knee, right arm and ribs”. On examination the chiropractor found lateral intercostal spasm, bilateral trapezius spasm, decreased motion of the cervical spine, patella abrasion and left SI rotation. He diagnosed her with multiple sprain/strain syndromes and recommended a course of chiropractic treatment. His reports in November, 1998 indicate that the worker’s symptoms were resolving with residual neck pain and spasm.

The worker then saw a family physician on November 9, 1998. She told the family physician that she had tripped over a mat in September and still had a sore neck. She did not find that the chiropractic treatments were helping. On examination, the family physician noted tenderness on the right C3, right trapezius trigger points, right side flexion and pain focused behaviour. An x-ray of the cervical spine taken the same day revealed mild degenerative narrowing involving the C5-6 intervertebral disc space associated with marginal spurring. The family physician diagnosed her with cervical strain and recommended home exercises and physiotherapy.

The worker reported increased pain with physiotherapy. The physiotherapist thought that the worker’s progress was slow due to a concomitant left TMJD problem.

The worker then saw her treating physician who noted good range of motion in her neck but subjective complaints of pain.

On January 20, 1999, the worker stopped working as she felt unable to cope with the pain. A January 27, 1999 WCB memorandum to file notes that the worker found her neck and jaw pain were worse and that her jaw had locked.

On February 2, 1999 the worker saw her treating physician and reported that she was slowly getting better but continued to have clicking in her jaw. On examination, the treating physician noted that all of the worker’s movements were stiff. The worker returned on February 4 and 8 with pain complaints. The treating physician continued to reassure the worker and recommend physiotherapy treatment.

In a progress report of March 9, 1999, the treating physician reported that the worker felt stressed and could not sit for any length of time. Her pain would increase when her head was down. The physician expressed concern that chiropractic treatment was making the worker’s TMJ problems worse. He noted that the worker was still off work and that she felt that she could not return to work.

The worker was examined by a WCB medical advisor on April 9, 1999 to determine her status and functional abilities. During the examination, the worker described her workplace injury as follows: “she was at work watering plants when she tripped over a floor mat. She states she fell forwards then backwards and then onto her left side. She was unsure if she hit her head. She did not lose consciousness although she stated she was in a “state of shock”, “dazed” and “traumatized”. She indicates she injured her neck, right shoulder, mid and lower back as well as left hip.” She described a worsening of symptoms in January 1999 when she began to have severe pain at her neck, jaw, tongue and mouth. She was unable to open her mouth as her jaw was sore and had “tightened up”. By the end of March 1999 she began to feel better but still complained of head and neck pain. On examination the WCB medical advisor noted minimal objective findings which would limit the worker from working at her regular duties.

On May 6, 1999, the WCB advised the worker that it would not pay her wage loss benefits for the time she was off work.

The worker returned to her regular duties and more than a year later, she called the WCB on May 17, 2000 and advised that she suffered a recurrence of her injury which caused her to go off work again as of May 1, 2000.

A report from an oral and maxillofacial surgeon dated May 26, 2000 indicates that the worker had complaints of facial pain. He first saw the worker in January 2000. He diagnosed her with facial and TMJ pain, ordered an MRI and prescribed splint therapy. The MRI, which was done on March 9, 2000, revealed an anterior discal displacement with only partial recapture. Degenerative changes were seen about both condylar heads.

The WCB medical advisor was unable to link this later diagnosis to the compensable injury given the late onset of the TMJ problems and the absence of documentation of jaw trauma at the time of her workplace injury.

On June 1, 2000, the WCB advised the worker that it did not consider her TMJ problems to be related to her compensable injury.

On August 15, 2000, the worker was seen by another WCB medical advisor. The worker described her workplace injury as follows: “She recalls “flying forward” and then backward, striking her neck and back of head against a steel drawer on a desk. She recalls experiencing immediate pain maximal through the cervical area, but also including the back and right shoulder. She states that she recalls the specific event, with no awareness of loss of consciousness.” She had chiropractic care and “sometime in December…following adjustments…she would experience pain through the posterior neck as well as over the temporomandibular joints bilaterally.” Based on this description of the mechanism of injury and the worker’s history of persistent jaw symptoms since chiropractic treatment in December 1998, the WCB medical advisor thought there was a temporal relationship between the onset of the worker’s jaw pain following the cervical sprain mechanism. He noted that despite the MRI findings of March 2000 which revealed degenerative changes, it was possible that muscular sequelae of the mechanism of injury led to an aggravation of a previously unrecognized pre-existing TMJ condition. He added however that the worker should remain in the workforce to prevent a chronic pain scenario.

In follow-up to his examination the WCB medical advisor called the worker’s treating oral and maxillofacial surgeon. An August 29, 2000 memorandum records this conversation:

“…the degenerative changes in the TM joints are bilateral. In view of complete absence of [symptoms] prior to CI [compensable injury], the possibility exists that at the time of the CI, with the strain mechanism, the discs (in the TMJ) could have been pulled forward which could have resulted in symptoms several weeks -> months later i.e. ‘based on development of scan, describes the [worker] as having chronic facial pain.”

Based on the call-in findings of August 15, 2000 and discussion with the examining WCB medical advisor on August 31, 2000, the WCB case manager accepted responsibility for the worker’s TMJ difficulties as an aggravation of a pre-existing condition and the worker’s compensation benefits were reinstated effective May 1, 2000.

The worker continued to see her treating oral and maxillofacial surgeon. In October 2000 she reported continuing tightness in her TMJs and neck but a reduced amount of pain which she attributed to her physiotherapy treatments and splint therapy. She also reported a speech problem that had developed. The treating oral and maxillofacial surgeon did not think that the worker’s speech problem was caused by her TMJD. When seen on October 25, 2000 the treating oral and maxillofacial surgeon noted deterioration in the worker’s attitude and pain situation. Her speech was difficult and she appeared depressed. He thought there were other factors at play besides temporomandibular joint pain and dysfunction and recommended referral to a psychologist.

The worker was referred by the WCB to a neurologist in November 2000. A copy of the WCB medical advisor’s call in examination of October 15, 2000 was provided. The neurologist records his findings and opinion in a November 15, 2000 report. He notes that the worker began experiencing speech problems in September 1999. The problems started as extra abnormal movements of her jaw and lips and had reached the point where she was only able to enunciate a few words with reasonable clarity; she had therefore taken to writing instead of speaking. The neurologist thought the worker’s symptoms were consistent with orobuccal lingual dystonia, the etiology of which was most likely, on the balance of probabilities, secondary to her history of trauma and presumably subsequent chronic pain as a result of the initial trauma together with either the resultant or aggravated temporomandibular joint pathology.

This diagnosis was confirmed on December 15, 2000 by the Department of Communication Disorders at the Health Sciences Centre. The speech pathologist and specialist in communication disorders diagnosed the worker with a traumatic injury to the temporomandibular joint and neck muscles with a secondary oral mandibular dystonia.

The worker was prescribed medication for her dystonia which initially provided some relief. By December 2001 however, she reported a significant worsening in her jaw, mouth and throat pain to the extent that she had difficulty swallowing and was unable to sleep. As medication therapy was not working, the neurologist recommended botulinum toxin injections. He also referred her to an orthopaedic specialist who diagnosed the worker with a myofascial pain syndrome and dystonia. It was his opinion that this condition had its origins in a functional problem such as anxiety or depression.

By September 17, 2002, the worker had reported improvement in her pain to her neurologist. The neurologist was not certain of the reason for her improvement but thought is was likely due to the worker’s improved psychological state. Given this improvement, the neurologist discharged her from his care.

Thereafter, the worker was followed by her family physician and underwent touch therapy with a chiropractor.

The worker’s functional status was explored by the WCB. A February 25, 2003 notation by a WCB psychiatric advisor indicates that it was unlikely that the worker’s psychological problems were contributing to her physical problems. It goes on to state that “in order to establish that there is a psychological cause for a physiological problem, the possible physical causes would need to be excluded”. In this case, the neurologist stated that the etiology of the problem was most likely due to the worker’s trauma.

Then in April, 2003 the worker was assessed by a psychiatrist. He diagnosed her with an adjustment disorder with depression, but no evidence of a major depression.

On September 2, 2003, the worker was interviewed by two medical advisors from the WCB’s pain management unit (“PMU”) to determine her current level of physical and psychological functioning. Following the assessment, it was determined that the worker did not meet the diagnostic criteria for chronic pain syndrome per WCB criteria, as her disability was not proportional in all areas of functioning. It was also determined that the worker was not experiencing a major depression and there were no significant barriers that would prevent her from attempting a graduated return to work program. This return to work was embraced by the worker’s treating psychologist.

The worker’s return to work was explored between the WCB, the worker and her accident employer beginning in about April 2003. The accident employer expressed some concerns about the worker’s ability to return to her previous job given its fast-paced nature and the fact that it was implementing a new computer system that the worker would not be familiar with.

While discussions were still taking place about the worker’s return to work, surveillance was taken of the worker. The WCB case manager found that based on the activities displayed on the surveillance, the worker had recovered from the effects of her compensable injury. On January 13, 2004, the WCB case manager advised the worker that the video surveillance demonstrated that she had no significant evidence of disability or pain behaviour which was inconsistent with her reports of disability with regard to her compensable neck injury. Following consultation with the WCB’s healthcare branch, it was determined that the worker had no physical restrictions arising from her compensable injury and that she was fit to return to her pre-accident employment which was considered sedentary in nature. Given the decision and based on subsection 39(2) of The Workers Compensation Act (the “Act”), wage loss benefits would be paid to January 27, 2004 inclusive and final. This decision was upheld by Review Office.

Notwithstanding this decision, the worker and accident employer devised a gradual return to work program which began in February 2004. The worker gradually returned to work at a rate of a half day over five days for the first week, full days over three days the next week, three-quarters of a day for the third week and then five days a week, full time. This graduated return to work was essentially an orientation period where the worker was introduced to the new technology and manuals. At the hearing the worker described that she was still in physical discomfort and stress from being overwhelmed during this time. The stress caused more pain in her head. She continued with full time orientation in March and in April returned to her full time regular duties for one week. The worker testified that she had a very difficult time with performing her duties because they had changed so much since she had last worked. She returned to training and was eventually provided an alternate job. By December 2004 the worker retired (in circumstances and for reasons which are not pertinent to this appeal).

Subsequent to her retirement, the worker found alternate employment on a part time basis which she continues to hold today.

Worker’s Position

The worker says that she is entitled to benefits beyond January 27, 2004 as she was still suffering from the effects of her compensable injury. Though she was ready to attempt a gradual return to work, and did so, she was not and is still not able to return to her full time regular duties.

Employer’s Position

The employer says that the worker was physically and psychologically able to return to full time duties. However, given that the worker had been on claim for over 5 years, they thought that benefits should be granted to the worker on a discretionary basis until the end of the graduated return to work as per WCB Policy 44.30.60.

Analysis

To accept the worker’s appeal we must find that after January 27, 2004 she continued to suffer from the effects of a compensable injury. We are unable to make that finding as we find that the worker’s only compensable injuries were sprain/strains and that she had recovered from the effects of these compensable injuries by January 27, 2004.

The Mechanism of Injury

In determining the worker’s compensable injuries, we have examined, determined and placed great weight on the mechanism of injury of the workplace accident.

The mechanism of injury has been reported by the worker to various medical practioners since her 1998 claim. We note that the description of this mechanism of injury has changed from her initial report of the accident. The initial report of the accident was of a simple trip over a mat with a subsequent fall and injury to the right side of her body. The subsequent reports add an injury to the head and direct trauma to both the neck and the head. The worker was asked to clarify her mechanism of injury at the hearing and draw a diagram to explain how the accident occurred. To the best of her recollection, the worker explained that she tripped on the corner of a mat and fell onto the side of a swivel chair on wheels. The chair moved forward with her movement. She rebounded off of the chair, did a ninety degree turn and landed on her buttocks, up against a steel cabinet or desk. We note that this description is dramatically different and is also inconsistent with the initial report of her accident report. In light of this inconsistency, we place more weight on the initial description of the workplace accident and find that the worker did not sustain any trauma to her neck or head.

The Compensable Injury

Given our view of the mechanism of injury, we find that the worker only suffered sprain/strains to her right knee, shoulder, back and neck. This is the initial diagnosis and is consistent with the subjective complaints and clinical findings at the time. These sprain/strains essentially resolved within two months with the exception of some residual pain complaints in her neck. We note however that the worker was able to work at her regular duties from the date of the workplace accident until January 1999 then again from May 1999 to May 2000 and thus we find that these strains/sprains had minimal effect on the worker’s functional capabilities. Interestingly, the medical reports from November 1998 forwards, and in particular the April 9, 1999 examination by the WCB medical advisor, indicate little in the way of clinical findings and support this conclusion.

The worker’s main ongoing complaints appear to be related to her TMJD and dystonia. As indicated previously these two conditions were accepted by the WCB as related to her compensable injury. We are unable to accept this determination because we find that there is insufficient evidence to link them to the workplace accident.

The basis for causally linking the TMJD and dystonia to the workplace accident appears to reside in the premise that the worker suffered trauma to her neck and head, and in a possibility of her muscular problems leading to the TMJD and dystonia.

As mentioned previously, we do not accept that the worker suffered trauma to her neck or head. We therefore do not accept that the workplace accident caused the worker’s TMJs to displace. Further, the first reports of TMJ-type symptoms were more than three months after the accident. Though TMJ can result from trauma and there is, as suggested by the neurologist, some medical evidence suggesting that it can result from severe flexion/extension type injuries, it can also result from natural processes. We find it noteworthy that the MRI of the worker’s TMJs revealed bilateral degenerative changes which could have been the cause of her symptoms.

Given that we do not accept that the mechanism of injury was sufficient to cause or aggravate the worker’s TMJD, we likewise do not accept that secondary link to dystonia. Once again the causes of dystonia are varied and while the neurologist suggests that trauma may cause it, we find there is insufficient evidence in the present case to link the dystonia to the workplace accident with any degree of certainty.