Decision #122/12 - Type: Workers Compensation
Preamble
The worker is appealing the decision made by Review Office of the Workers Compensation Board ("WCB") which determined that a Medical Review Panel would not be convened. The worker's position was that there was difference of medical opinion between the WCB medical advisor and her physician on a medical matter that was affecting her entitlement to benefits. A file review was held on September 20, 2012 to consider the matter.Issue
Whether or not a Medical Review Panel should be convened pursuant to subsection 67(4) of the Act.Decision
That a Medical Review Panel should be convened pursuant to subsection 67(4) of the Act.Decision: Unanimous
Background
On August 11, 2009, the worker filed a claim with the WCB for a right shoulder injury that she related to the lifting of a client on August 2, 2009. The claim for compensation was accepted by the WCB and benefits and services were paid to the worker while she underwent treatment for her shoulder injury. The initial diagnosis was a right rotator cuff strain.
Medical information showed that the worker had an MRI of her right shoulder taken on November 18, 2009. The results were reported as showing a normal rotator cuff and minor subacromial bursal fluid. The worker was subsequently diagnosed as having adhesive capsulitis stemming from the compensable injury and the worker underwent treatment in the form of right suprascapular nerve blocks and physiotherapy. As the worker continued to complain of ongoing pain in her shoulder, the worker was seen at the WCB's offices on December 20, 2010 for a call-in medical assessment.
On December 20, 2010, the WCB medical advisor outlined the opinion that the adhesive capsulitis in the right shoulder had resolved and a repeat MRI of the shoulder should be arranged to determine if there had been a change in the worker's rotator cuff.
An MRI of the right shoulder was done on February 22, 2011 and a partial tear of the right supraspinatus was identified.
On March 8, 2011, a WCB medical advisor outlined the opinion that the partial tear of the right supraspinatus accounted for the positive impingement signs elicited during the call-in examination of December 20, 2010. Given that the initial MRI performed three months after the date of injury demonstrated no supraspinatus pathology, it was felt that the current diagnosis was not accounted for by the workplace injury sustained on August 2, 2009.
By letter dated April 15, 2011, the worker was advised that based on the accident description, diagnosis and treatment rendered and the current medical findings, it was the opinion of the WCB that she had recovered from the effects of the August 2, 2009 workplace injury and any ongoing right shoulder difficulties were unrelated.
In May 2011, the worker provided the WCB with a report from an orthopaedic consultant dated April 12, 2011. The consultant outlined the view that the partial tear of the supraspinatus tendon came about from the lifting incident at work. On May 5, 2011, a WCB sports medicine consultant outlined his opinion that based on the results of the two MRI scans that were performed on November 18, 2009 and February 22, 2011, the information did not support a temporal relationship between the new diagnosis of a tear and the August 2, 2009 workplace injury.
On May 11, 2011, the worker was advised that no change would be made to the decision outlined on April 15, 2011 based on the opinion expressed by the WCB consultant on May 5, 2011.
On July 5, 2011, the worker underwent surgery to her right shoulder and the post-operative diagnosis was rotator cuff disease and AC joint arthritis right shoulder.
Based on an appeal submitted by the worker, Review Office requested an opinion from a WCB orthopaedic consultant with respect to the worker's right shoulder. On July 13, 2011, the WCB orthopaedic consultant stated:
1. The diagnosis of the workplace injury was probably a rotator cuff strain. Had there been a cuff tear it is more likely than not that it would have been demonstrated on MRI on 18-Nov-2009.
2. The diagnostic clinical criteria for adhesive capsulitis (frozen shoulder) are not a subject of general consensus. As a result of the workplace injury, there may have been an element of adhesive capsulitis with gradual recovery of range of motion over a year or so. Alternatively, the reduced ROM may have been related to a combination of the rotator cuff strain and a slowly developing degenerative tear of the rotator cuff.
3. The partial thickness tear of the rotator cuff demonstrated on MRI of 20-Feb-2011 (sic) must have developed in the time interval between 18-Nov-2009 and 20-Feb-2011 as there is a low probability that it was missed in the first MRI. There is no objective evidence that the partial thickness tear was caused by WCB-sponsored treatment of the right shoulder.
4. I have reviewed the discs of the two MRI's (sic) have compared them directly. I agree with the radiology reports that there was no tear visible on the MRI of 18-Nov-2009.
On July 20, 2011, Review Office confirmed that there was insufficient evidence to support that the worker sustained a rotator cuff tear as a result of the workplace accident on August 2, 2009 or as a result of any treatment she received from her right shoulder injury. It found no evidence on file to support a causal relationship between the worker's current difficulties and the August 29, 2009 compensable injury.
On January 31, 2012, the Worker Advisor Office requested reconsideration of the decision made by Review Office dated July 20, 2011 based on a January 6, 2012 report from the treating orthopaedic surgeon. The worker advisor submitted that the file information and the orthopaedic surgeon's opinion supported that the rotator cuff tear occurred as a result of the accident sustained by the worker while performing her work duties.
In his January 6, 2012 report, the treating orthopaedic surgeon stated:
1. The working diagnosis of the August 2, 2009 work-related injuries were rotator cuff tearing and acromioclavicular joint injury.
2. The pre-operative diagnosis was articular sided rotator cuff tear and AC joint injury with AC joint arthritis. The post-operative diagnosis was rotator cuff tear, but more extensive on the bursa side in association with tight sub-acromial space and persistent sub-acromial impingement.
3. In view of the historical continuity in symptoms from the time of injury to the time of surgery, the relationship is rotator cuff injury following work injury.
4. Although MRI is a very helpful imaging tool in assessing presence, location, and extent of rotator cuff tearing, findings at surgery are the gold standard, or at least should be.
I would tend to disagree with the WCB opinion that this patient had a normal cuff in 2009 and then just wore it out and tore it over the next year and a half, particularly during the period of reduced use and reduced mobility and function with the documentation of associated stiffness and/or adhesive capsulitis ongoing. As a second point, the surgery findings did not even agree with the second MRI findings, as there was minimal articular-sided tearing at arthroscopy, but extensive bursa-sided tearing. Clinical photos were taken for this, if required, at a Review Panel and are on my office file.
While I am not able to comment with certainty regarding the actual state of the rotator cuff at the time of the initial MRI, it has been my experience that MRI findings do not correlate particularly well with surgical findings. To reach a scientific conclusion about the frequency of discordance between MRI findings and surgical findings, would require both an exhaustive review of the literature, and even more importantly, a regional review and I do not believe such a prospective or retrospective study has been performed.
5. Given the factors in this case, I would lend my support to higher probability of significant rotator cuff injury at the time of initial injury, not fully appreciated on initial MRI.
On February 22, 2012, the WCB orthopaedic consultant provided the following opinion:
I understand the opinion of [orthopaedic surgeon] to be based on:
a) The continuity of symptoms following the workplace injury
b) The probability that there was a false negative first MRI
c) The low probability that the tear occurred during a period of low level use of the shoulder
d) That the second MRI was not consistent with the subsequent arthroscopy findings.
a) I agree that symptoms have continued. It is probable that rotator cuff strain would cause symptoms resembling those of a rotator cuff tear, and the differentiation would normally be by imaging study of MRI.
b) MRI is reported in medical literature to be a very sensitive and specific means of diagnosing rotator cuff tears in the shoulder. The medical literature reports sensitivity of between 77% and 100% in various studies, the 100% being a report by Lambert et al. Magee et al described 26 out of 26 partial thickness tears to be detected by MRI, and 96 out of 98 full thickness tears to be detected. There has not been a similar audit study carried out in Manitoba.
...
c) There is a significant degenerative factor in development of rotator cuff tears, and tears often occur in shoulders with low level activity. In geriatric age ranges, most people have defects in their rotator cuffs.
d) The second MRI was reported as showing an almost full thickness tear mainly on the articular side. Arthroscopy findings were of an almost full thickness tear mainly on the bursal side. The correlation was limited to a finding of an almost full thickness tear. Had there been such a tear at the time of the first MRI, it is very probable that it would have been observed and reported.
On balance of probabilities, the tear of the rotator cuff was not caused by the workplace injury."
A copy of the WCB medical opinion dated February 22, 2012 was provided to the Worker Advisor Office for comment. On March 5, 2012, the worker advisor outlined the position that the weight of evidence supported that the rotator cuff tear was the injury resulting from the August 2, 2009 workplace accident. The worker advisor asked that Review Office adopt the treating orthopaedic surgeon's opinion over the opinion expressed by the WCB orthopaedic consultant.
On April 5, 2012, Review Office upheld that the worker was not entitled to wage loss benefits beyond April 20, 2011. Review Office accepted the opinion of the WCB orthopaedic consultant that the tear of the rotator cuff was not caused by the August 2009 workplace injury.
On April 26, 2012, the Worker Advisor Office requested a Medical Review Panel ("MRP") in accordance with subsection 67(4) of The Workers Compensation Act (the "Act"). It was felt that there was a difference of medical opinion, with respect to a medical matter, which was affecting the worker's entitlement to compensation benefits. The difference of medical opinion was between the WCB orthopaedic consultant and the worker's attending orthopaedic surgeon.
On April 8, 2012, it was determined by primary adjudication that an MRP would not be granted. It was felt that there was no difference in medical opinion as the WCB did not dispute that the worker suffered a rotator cuff tear. What was disputed was the causal relationship between the rotator cuff tear and the worker's employment, which was an adjudicative decision and that there was sufficient evidence on file that supported on a balance of probabilities there was no causal relationship in this case. On May 25, 2012, the Worker Advisor Office appealed this decision to Review Office.
On July 24, 2012, Review Office determined that an MRP should not be convened in accordance with subsection 67(4) of the Act. Review Office indicated that a review of medical evidence showed there was no difference of opinion with respect to the worker's diagnosis of a right rotator cuff tear. The July 13, 2011 opinion by the WCB orthopaedic consultant acknowledged that the worker's "partial thickness tear of the rotator cuff," was demonstrated on the February 22, 2011 MRI. The treating orthopaedic surgeon confirmed the diagnosis of a right rotator cuff tear in his January 6, 2012 report.
Review Office noted there was disagreement on whether the worker's accident caused the diagnosis of a right rotator cuff tear. It found that this determination was an adjudicative matter/decision and was the responsibility of the WCB based on the weighing of file evidence which included but was not limited to information presented by the worker, the orthopaedic surgeon and the WCB orthopaedic consultant. Review Office determined that a MRP should not be convened as the requirements of subsection 67(4) had not been met.
On August 10, 2012, the Worker Advisor Office appealed Review Office's decision to the Appeal Commission and a file review was arranged.Reasons
Applicable Legislation and Policy
The Appeal Commission and its panels are bound by the Act, regulations and policies of the Board of Directors.
The worker has requested that an MRP be convened pursuant to subsection 67(4) of the Act. The relevant provisions are subsections 67(4) and 67(1).
Subsection 67(4) provides:
Reference to panel on request of worker
67(4) Where in any claim or application by a worker for compensation the opinion of the medical officer of the board in respect of a medical matter affecting entitlement to compensation differs from the opinion in respect of that matter of the physician selected by the worker, expressed in a certificate of the physician in writing, if the worker requests the board, in writing before a decision by the appeal commission under subsection 60.8(5), to refer the matter to a panel, the board shall refer the matter to a panel for its opinion in respect of the matter.
Subsection 67(1) defines opinion as "a full statement of the facts and reasons supporting a medical conclusion."
Worker’s Position
The worker was assisted by a worker advisor with the appeal. The position put forward on behalf of the worker was that where medical information is used to determine if benefits are payable, and the requirements of subsection 67(4) have been met, the right to an MRP arises. In this case, the Review Office relied upon the opinion of a WCB medical advisor, who used medical information to exclude a potentially compensable diagnosis of rotator cuff tear. As there was a clear difference of opinion between the WCB medical advisor and the treating orthopaedic surgeon as to whether the rotator cuff tear was a compensable injury, the WCB was required to refer the matter to an MRP for its opinion.
Analysis
To accept the worker’s appeal we must find on a balance of probabilities that the medical opinion of a WCB medical officer differs from the opinion of the worker’s physician within the meaning of subsections 67(4) and 67(1) of the Act. We are able to make that finding.
After reviewing the medical reports on file, the panel finds that there is a difference of opinions in respect of a medical matter affecting entitlement. The WCB orthopaedic consultant and the treating orthopaedic surgeon differed in their opinions regarding the diagnostic qualities of MRI imaging and the extent to which the MRI findings of November 18, 2009 and February 22, 2011 can be relied upon to determine how long the rotator cuff tear repaired during surgery had been present in the worker's shoulder. The difference in opinion regarding the sensitivity of MRI findings led the physicians to place differing degrees of weight on the MRI reports and ultimately led them to arrive at differing opinions on whether the diagnosis of a rotator cuff tear was medically accounted for in relation to the workplace injury. While an opinion of this nature comes very close to constituting an opinion on causation, it is still a matter upon which a physician may opine, as it relates to medical findings.
The panel agrees with Review Office that the ultimate determination of causation is an adjudicative decision which rests with the WCB/Appeal Commission but also notes that there are many inputs to the adjudicative process, including various medical opinions that affect these decisions.
For the foregoing reasons, the panel finds that the requirements of subsections 67(1) and 67(4) are met and a MRP should be convened. The worker’s appeal is allowed.
Panel Members
L. Choy, Presiding OfficerA. Finkel, Commissioner
P. Walker, Commissioner
Recording Secretary, B. Kosc
L. Choy - Presiding Officer
Signed at Winnipeg this 9th day of November, 2012