The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

The worker is appealing decisions that were made by the Workers Compensation Board ("WCB") regardinghis left knee claims.  A hearing was heldon December 9, 2015 to consider the worker's appeal.

Issue

2007 Workplace Injury

Whether or not the worker is entitled to benefits after January 7, 2008;

1992, 1986 and 1977 Workplace Injuries

Whether or not the worker's current left knee difficulties are a consequence of the workplace injuries sustained October 15, 1992, September 5, 1986, May 21, 1986, February 3, 1986 and/or May 27, 1977.

Decision

2007 Workplace Injury

That the worker is not entitled to benefits after January 7, 2008;

1992, 1986 and 1977 Workplace Injuries

That the worker's current left knee difficulties are not a consequence of the workplace injuries sustained October 15, 1992, September 5, 1986, May 21, 1986, February 3, 1986 and/or May 27, 1977.

Decision: Unanimous

Background

The worker has prior claims with the WCB for left knee injuries that occurred in 1977, 1986 and 1992.

On June 25, 2007, the worker filed a claim for a left knee injury that occurred on June 21, 2007 when he slipped while getting out of his transport truck.

A Chiropractor's First report dated June 29, 2007 indicated that the worker injured his left knee when he fell down a couple of stairs while getting out of his truck. The chiropractic diagnosis was a traumatic knee strain with possible ligamentous damage.

On June 26, 2007, the worker underwent a left knee x-ray which was read as showing "Advance osteoarthritis at both patellofemoral articulation and true knee joint with medial joint space narrowing of the true knee joint."

On August 22, 2007, the worker was seen at the WCB's offices by a chiropractic consultant for an assessment of his knee condition. During the interview portion of the assessment, the worker indicated that he had left knee surgery in 1981, at which time cartilage was removed, and that he had a left knee arthroscopic procedure in 1986. In 1985, he had an arthroscopic procedure to his right knee. The chiropractic consultant stated that in his opinion, the worker's current left knee condition in all probability involved the cartilaginous and ligamentous structures of the left knee. Arrangements were then made for the worker to see a sports medicine physician for an evaluation of his left knee status.

In a report to the WCB dated August 27, 2007, the sports medicine specialist concluded that there was severe medial compartment osteoarthritis ("OA") and probable ACL insufficiency in the worker's left knee. He said it was likely that the workplace incident in June 2007 perturbed this osteoarthritic change. It was possible that the ACL tearing/insufficiency occurred during the incident, although it was likely more probable that this was an old feature. The worker's current symptoms were likely related to the medial compartment OA.

Subsequent file records showed that a WCB vocational rehabilitation consultant met with the worker in May 2008 to develop a vocational rehabilitation plan given that the worker's knee condition prevented him from returning to his pre-accident employment.

In a progress report dated October 11, 2013, the treating sports medicine specialist stated that the worker required a total knee arthroplasty ("TKA") as the worker was experiencing deterioration in terms of ADL's (activities of daily living) and pain symptoms.

On November 21, 2013, a WCB orthopedic consultant was asked to review the worker's file and respond to specific questions related to the worker's knee condition. The consultant opined that the worker's current symptoms were related to his pre-existing condition of advanced OA of the left knee and that it was not related to the June 21, 2007 workplace injury. It was also the consultant's opinion that the required TKA was not a result of the workplace injury but was due to the OA in the worker's knee. Based on this medical opinion, the worker was advised by letter dated December 16, 2014 that his current left knee symptoms were not related to the original injury of June 21, 2007 and therefore the proposed surgery and/or time loss would not be approved by the WCB.

On January 29, 2014, the worker's file was again reviewed by the WCB orthopedic consultant. He commented that the workplace injury caused a non-specific sprain of the left knee in the environment of severe pre-existing OA. The worker's current symptoms were entirely caused by the natural deterioration over time of the knee OA rather than the workplace injury. The consultant said there was no clinical medical evidence that the workplace injury aggravated or enhanced the pre-existing OA.

By letter dated February 28, 2014, the worker was advised by the WCB that the information on file indicated that he had recovered from the left knee strain injury of June 21, 2007 and that responsibility for wage loss or medical treatment would not be paid beyond April 11, 2014. It was confirmed that the TKA was due to his pre-existing OA and was not the result of the workplace injury. In May 2014, the worker appealed the decision to Review Office.

On July 2, 2014, the WCB orthopedic consultant commented as follows after reviewing the worker's prior knee claims:

At issue is whether or not the workplace injury of May 21, 1985...may have caused a tear of the ACL of the left knee. Arthroscopy was carried out by [surgeon] on July 24, 1986, but the O.R. report is not on WCB file. [Surgeon] later mentioned "previous" ACL insufficiency. However, it is not clear if the ACL damage may have occurred in 1986 or before that time, as in the 1982 injury in Calgary. As ACL deficiency is a known cause of osteoarthritis (OA), it is probable that the ACL tear contributed to the onset of OA of the left knee. In the absence of documentation that the ACL tear occurred as a result of the May 21, 1986, workplace injury, it is not possible to demonstrate that the current OA is related to workplace injury. It may be possible to obtain a copy of the missing O.R. report from archives at HSC or Winnipeg Clinic, as discussed with Case Management.

On July 16, 2014, Review Office determined that the worker had recovered from the effects of his compensable left knee strain by January 7, 2008 and that he was not entitled to benefits beyond that date.

Review Office indicated that the worker's compensable injury involved a strain to his left knee in the environment of severe degenerative changes. This was supported by the June 2007 x-ray results. Review Office indicated that the severe degenerative changes represented a pre-existing condition which was not caused by the June 21, 2007 workplace accident. Review Office was also of the opinion that the pre-existing condition impacted/delayed the worker's recovery from his compensable injury.

Review Office concluded that the worker's loss of earning capacity and need for medical aid beyond January 7, 2008 was not related to the compensable left knee strain. After that point in time, the worker's compensable injury was no longer materially contributing to his ongoing disability.

Regarding the relationship between the worker's prior injuries and the worker's current left knee difficulties, the WCB orthopedic consultant stated on July 24, 2014:

An arthroscopy of the left knee report dated July 24, 1986, is now on file...

1. It is probable that stretching and clinical insufficiency of the ACL led to the OA findings visualized at arthroscopy on July 24, 1986, even though the ACL was visualized to be intact.

2. Stretching of the ACL could have occurred at any time prior to July, 1986. The findings of quite early OA changes would tend to point to ACL injury at some time. On February 19, 1986, [surgeon] noted "old ACL deficiency".

3. The reported mechanism of workplace injury on May 21, 1986, is consistent with a stretching injury of the ACL. There is, however no objective medical evidence that the injury of May 21, 1986, was the direct cause of the ACL insufficiency. It is more probable that the ACL injury was pre-existing.

By letter dated September 9, 2014, the worker was advised that the WCB had completed a review of his prior left knee claims to see if there was any further WCB responsibility. The case manager indicated that the medical information did not establish a cause/effect relationship between his five prior left knee claims and his current left knee difficulties.

In a report dated October 20, 2014, an occupational health physician opined that the worker's injury and history and the development of degenerative left knee condition, was work related, on a balance of probabilities. He stated:

All significant injuries took place in the line of work. His first injury associated with articular damage in 1980 was work related by a Manitoba Employer working out of Province for which there was no former claim file. The meniscectomy is a risk factor for further degeneration of the joint. Subsequent work injuries in Manitoba were associated with further surgical procedures and time loss from which he was able to recover, not this last injury of 2007.

Importantly, his left knee condition is work related and should be compensable...The 2007 injury involved significant impact, given the nature of his fall and the recurrent knee swelling, pain and requirement for leg bracing to manage.

In a decision dated February 2, 2015, Review Office indicated that the information contained in the October 20, 2014 medical report did not alter its previous decision. Review Office indicated that the decision took into account the condition of the worker's left knee before his accident with the employer on June 21, 2007. It its opinion, the accident did not change the status of the pre-existing condition, the worker's difficulties beyond January 7, 2008 are not compensable.

In a report dated February 24, 2015, the treating sports medicine specialist stated:

The above's knee condition, in the writer's opinion, is materially based upon his workplace injury in 2007, which caused symptomatic enhancement of his knee osteoarthritis. He has never returned to his previous baseline function since the injury, and is now awaiting a TKA.

Though we can take into account the natural progressive history of the osteoarthritis, it is the writer's opinion that the 2007 workplace injury is a material contributor in his current knee presentation.

In a letter dated March 3, 2015, Review Office advised the worker that the February 24, 2015 medical report contained no new evidence to support that he was entitled to benefits beyond January 7, 2008.

On May 20, 2015, the Worker Advisor Office requested Review Office to determine whether there was a causal relationship between the worker's prior left knee claims and his current left knee difficulties. The worker advisor stated in part:

[Surgeon's] July 24, 1986 operative report was obtained and identified "early degenerative changes medial compartment and laxity of anterior cruciate ligament". It is our opinion if only early degenerative changes were noted at the July 24, 1986 procedure then it is unlikely the changes are related to the 1982 injury which occurred four years previous and more likely related to the compensable February 3, 1986 injury. Therefore evidence supports [the worker's] current left knee difficulties are causally related.

We also ask Review Office to consider a relationship between the accumulative effects of numerous left knee injuries and the June 21, 2007 injury. [The worker] says he has been severely disabled since this incident and is scheduled for a left knee replacement August 2015.

In a letter dated May 25, 2015, Review Office advised the worker that the recent appeal from his representative contained no new evidence and therefore Review Office would not reconsider the previous decisions it made on his 2007 claim.

On June 9, 2015, the Worker Advisor Office appealed Review Office's decisions to the Appeal Commission and an oral hearing was arranged.

Reasons

Applicable Legislation

The Appeal Commission and its panels are bound by The Workers Compensation Act (the “Act”), regulations and policies of the Board of Directors.

The worker is appealing 2 issues. He has an accepted claim for a left knee injury which occurred in 2007 and is seeking further benefits on this claim. He also has 5 other accepted claims relating to his left knee and is seeking a decision that his current left knee difficulties are a consequence of the these prior injuries.

Under subsection 4(1) of the Act, where a worker suffers personal injury by accident arising out of and in the course of employment, compensation shall be paid to the worker by the WCB.

Subsection 27(1) empowers the WCB to provide such medical aid as the WCB considers necessary to cure and provide relief from an injury.

Subsection 39(1) of the Act provides that wage loss benefits will be paid: "…where an injury to a worker results in a loss of earning capacity…" 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.

Worker's Position

The worker was represented by a worker advisor who made a submission on the worker's behalf. The worker answered questions from his representative and the panel.

The worker advisor advised that it is the worker's position that the 1986, 1992 and 2007 workplace injuries, contributed to the development of his left knee condition and the need for the September 1, 2015 TKA.

She noted that the worker had six compensable injuries and one non-compensable injury to his left knee. She also noted that the worker had a non-compensable left knee medial meniscectomy in 1982, and a non-approved left knee diagnostic arthroscopy July 24, 1986.

The worker advisor noted that:

• three of the compensable injuries occurred in 1986 only a few months apart and the July 24, 1986 diagnostic arthroscopy identified early medial compartment arthritis and stretching of the ACL that occurred prior to 1986.
• the 1986 and 1992 compensable injuries were diagnosed as a strain, a twist, a sprain and an aggravation of a pre-existing condition. All these injuries occurred in the environment of degenerative left knee changes.
• a WCB medical advisor opined in a memorandum on file, dated July 24, 2014, that the reported mechanism of the May 21, 1986 injury is consistent with a stretching injury of the ACL.

She acknowledged that there is no clinical evidence that the injury of May 21, 1986 was the direct cause of the ACL insufficiency.

The worker advisor stated that the worker is not disputing the May 21, 1986 injury was not a direct cause of the ACL insufficiency, but it is the worker's opinion, based on the WCB medical advisor’s opinion that the May 21, 1986 injury could have contributed to additional stretching of the ACL. She said that the abnormalities may include joint instability and joint surface/cartilage injuries which may affect the articular surfaces of the joint.

The worker advisor noted that on June 21, 2007, the worker was getting out of his semitrailer truck when the wind caught the door, causing him to miss the steps and land on the ground, hyper-extending his left leg and jamming his knee. Following the incident, he was never able to get back to his pre-accident status.

The worker advisor referred to the opinion of the worker's treating physiotherapist, dated November 30, 2015 which states that, given the history of approximately six injuries, all involving the left knee, which typically included an extended knee, it would be reasonable to consider that the knee joint may have been left with some residual joint abnormalities following these multiple traumas.

She also noted that the worker's treating physician diagnosed severe and medial compartment osteoarthritis and probable anterior cruciate ligament insufficiency. She submitted that it would be reasonable to consider that these joint changes might contribute to post-traumatic arthritis and that there may also have been an accumulative affect of these multiple injuries over the course of decades. She relied on the treating sports medicine specialist statement in his report that the workplace accident had perturbed the worker's osteoarthritic changes.

The worker advisor submitted that the 2007 workplace injury is a material contributor in the worker's current knee presentation. She also submitted that the 1986 and 1992 compensable injuries contributed to the progression of the worker's left knee condition.

In answer to a question, the worker advisor confirmed that they could not relate the worker's knee problem to the 1977 injury. She agreed that there was no internal damage to the knee identified in 1977 injury. The worker advisor also confirmed that they do not attribute the degeneration seen in 1986 to the earlier 1986 injury.

The worker described his injuries and accidents commencing with the 1977 injury. With respect to the 2007 injury, he described it as follows:

And as I was getting out, when you’re getting in and out of a truck, or a trailer, or whatever, you use 3-point contact. You either have one hand and two feet, or two hands and one foot when you’re climbing.

Because a truck is like, you know, a load is five, six, seven feet. A truck is four and a half feet, and I was going to get out, I had the door open, I was getting ready to step out, and the wind caught the door.

And the wind was so violent that day, like a vehicle has a door stopper, it only opens so far. That day it wrapped the door right around to the fender on the Peterbilt. It broke the stopper. And I basically got flung out on the ground and I hyperextended my knee...it was swollen like a football and I was buggered up, but you know, we took it easy for a couple of days.

He also described his return to work after the 2007 injury which involved a variety of duties including security work and operation of a forklift.

The worker expressed concern with the opinion by the WCB orthopedic consultant. He noted that the orthopedic consultant did not examine him and had never met him.

The worker advised that he had a TKA in September 2015 and is currently recovering.

Employer's Position

The employer was represented by an advocate and its Safety Officer. The employer representative provided a copy of her written submission.

The employer's representative submitted that the weight of evidence supports the fact that the worker's ongoing problems with the left knee are due to pre-existing advanced osteoarthritis, and not the strain injury that occurred while working with the employer on June 21, 2007.

She said that the pre-existing condition of advanced osteoarthritis is documented in the x-ray evidence dated June 26, 2007, which was a few days after the incident. She noted that prior left knee surgeries were carried out in 1981, 1985 and 1986. She said that the employer agrees with the opinion of the WCB orthopedic consultant, dated November 21, 2013, which indicated that the current symptoms are those of advanced osteoarthritis of the left knee.

The employer representative submitted that, on a balance of probabilities, the osteoarthritis is not the result of the workplace injury of June 21, 2007. Rather, the current degree of osteoarthritis represents the natural history of pre-existing osteoarthritis. With respect to whether the 2007 injury perturbed the pre-existing condition, the employer representative said that in a knee with advanced OA, any sudden movement would be expected to cause symptoms.

She said that there’s no medical evidence that the workplace injury aggravated or enhanced the pre-existing advanced osteoarthritis of the left knee and that the natural history of osteoarthritis has reached a severity that a TKA was needed.

The employer representative agreed with the opinion of the WCB medical advisor that the workplace injury caused a non-specific strain of the left knee in the environment of severe pre-existing osteoarthritis.

With respect to the second issue, whether or not the left knee difficulties are a consequence of a cumulative effect of all of the injuries, the employer's representative said the information on file indicates that the worker had recovered from his prior left knee claims, and that ongoing issues are related to the advanced pre-existing osteoarthritis.

Analysis

The issues in this appeal are closely related. The evidence established that over the years, commencing in 1977, the worker has injured his left knee on several occasions. He has had both compensable and non-compensable surgery on his left knee. Based on the panel's assessment of the accidents, and medical information regarding diagnosis and treatment, the panel has concluded that the worker is not entitled to further benefits arising from any individual compensable accident or the cumulative effect of any of the accidents.

Issue 1: Whether or not the worker is entitled to benefits after January 7, 2008.

For the worker's appeal of this issue to be approved, the panel must find that the worker continued to suffer a loss of earning capacity and required medical aid benefits as a result of the 2007 injury. The panel was not able to make this finding.

The panel notes:

• the treating chiropractor described the injury as a sprain in his June 2007 report.
• reports of swelling depending on activity.
• the worker received chiropractic treatment for his knee and the treating chiropractor reported on December 31, 2007 that chiropractic treatment of the knee was complete.
• the treating physician's report of January 7, 2008 which indicates "improving. Brace helpful, Getting bored on reduced duties, mild effusion, much improved quad girth L, resolving OA+/- ACL insufficiency".
• "advanced osteoarthritis at both the patellofemoral articulation and true knee joint with medial joint space narrowing of the true knee joint" is documented in an x-ray report dated June 26, 2007.

• the WCB orthopedic specialist's opinion of November 21, 2013 that:

1. Current symptoms are those of advanced osteoarthritis (OA) of the left knee. On balance of probabilities, the OA is not the result of the workplace injury of 21-June 2007. Rather, the current degree of OA represents the natural history of pre-existing OA.

2. The pre-existing condition of "advanced OA" is documented in the x-ray report dated 26-June-2007. Prior left knee surgery was carried out in 1981, 1985 and 1986, according to the WCB call-in notes dated 22-Aug-2007.

3. It was considered by the sports medicine physician on 27-Aug-2007 that the workplace injury "perturbed" the OA. In a knee with advanced OA, a sudden movement would be expected to cause symptoms. However, the natural history of knee OA is of episodes of knee pain and stiffness which increase in frequency, duration and severity over the years. This pattern of symptoms is evident in the medical history of this individual. There is no clinical medical evidence that the workplace injury aggravated or enhanced the pre-existing advanced OA of the left knee.

4. The natural history of OA has reached a severity that total knee arthroplasty (TKA) is now being considered. The TKA is being considered because of the pre-existing OA and not as a result of the workplace injury.

5. WCB Healthcare has no ability to facilitate consultations with arthroplasty surgeons.

The panel places weight on these reports in finding, on a balance of probabilities, that the worker's left knee injury, to the extent that it was related to the 2007 accident, had resolved.

The panel acknowledges that the worker continued to have symptoms in his left knee but cannot relate the ongoing symptoms to the June 2007 accident, which the panel finds to have been a non-specific sprain of the left knee in the environment of severe pre-existing osteoarthritis, as diagnosed by the WCB orthopedic specialist.

The worker's appeal of this issue is dismissed.

Issue 2: Whether or not the worker's current left knee difficulties are a consequence of the workplace injuries sustained October 15, 1992, September 5, 1986, May 21, 1986, February 3, 1986 and or May 27, 1977.

For the worker's appeal of this issue to be successful, the panel must find that the worker's current knee difficulties are a consequence of the noted accidents. The panel was not able to make this finding.

In arriving at our decision, the panel placed significant weight on the opinion of the WCB orthopedic specialist. Specifically, we accept his opinion that:

An arthroscopy of the left knee report dated July 24, 1986, is now on file...

1. It is probable that stretching and clinical insufficiency of the ACL led to the OA findings visualized at arthroscopy on July 24, 1986, even though the ACL was visualized to be intact.

2. Stretching of the ACL could have occurred at any time prior to July, 1986. The findings of quite early OA changes would tend to point to ACL injury at some time. On February 19, 1986, [surgeon] noted "old ACL deficiency".

The panel also notes the opinion of the October 20, 2014 report of the occupational health physician who reviewed the worker's file and medical records. The occupational health physician opined that:

By my assessment, in reviewing [worker's] injury and history and the development of degenerative left knee condition, this is, in my opinion, work related, on a balance of probabilities. All significant injuries took place in the line of work. His first injury associated with articular damage in 1980 was work related by a Manitoba Employer working out of the Province for which there was no former claim file. The menisectomy is a risk factor for further degeneration of the joint. Subsequent work injuries in Manitoba were associated with further surgical procedures and time loss from which he was able to recover, not this last injury of 2007. (emphasis ours)