Decision #64/12 - Type: Workers Compensation
Preamble
The worker is appealing the decision made by Review Office of the Workers Compensation Board ("WCB") that his right meniscus tear was not related to his workplace injury that occurred on May 26, 2010. A hearing was held on February 28, 2012 to consider the matter.
Issue
Whether or not the worker's right meniscus tear is related to the compensable injury of May 26, 2010.
Decision
That the worker's right meniscus tear is not related to the compensable injury of May 26, 2010.
Decision: Unanimous
Background
The worker filed a claim with the WCB for an injury to his right lower leg that occurred on May 26, 2010 from the following work-related accident:
I was loading market hogs and a hog hit me from the side with his nose in my right lower leg. I stumbled but did not fall down. There were over 25 hogs in the area at the time. The hog was 280 to 300 lbs.
The worker advised that he did not seek medical attention immediately after the accident as he thought it was just a twist and the discomfort would go away but it did not.
On June 14, 2010, the worker advised a WCB adjudicator that he was loading hogs in a very confined area when one hog got spooked, ran at him and struck him on the side of his right calf. He tried to keep working for the next few days but it was too painful. The worker experienced difficulty with weight bearing, his knee was painful to the touch and his right leg was swollen.
The claim for compensation was accepted by the WCB and benefits and services were paid to the worker. The compensable diagnosis was a right leg and knee contusion.
Medical information showed that the worker underwent a right leg vein sonogram on June 1, 2010. There was no evidence of deep vein thrombosis. On June 7, 2010, the worker had right knee x-rays which showed a small joint effusion and no evidence of a fracture or dislocation. On June 10, 2010, x-rays of the right tibia and fibula were taken and a small avulsion-type fracture was seen.
The worker saw a physiotherapist in June 2010 and was diagnosed with a right gastrocnemius tear.
A bone scan taken July 14, 2010 indicated that: "there is no scintigraphic evidence to suggest a stress fracture or other active pathology affecting the right leg."
On August 9, 2010, the treating physician reported that the worker could not put full weight onto his right leg due to pain on the outside. Range of motion was gradually improving but very slowly.
On August 26, 2010, a WCB orthopaedic consultant reviewed the file and stated that the diagnosis of the compensable injury was not clear. The differential diagnoses were a contusion, haematoma or muscle rupture of the right calf.
A right leg MRI was done on September 10, 2010. The report stated: "…there is no evidence for hematoma. The musculature demonstrates normal morphology and signal intensity."
On September 30, 2010, the worker's treating physiotherapist advised the WCB that the worker had atrophy over the right calf with lateral/proximal calf pain with ambulation or increased lower extremity strengthening. The worker denied numbness or tingling in the lower extremities. It was felt that the worker was not progressing as anticipated given the normal ultrasound, bone scan and MRI. The physiotherapist suggested possible compartment syndrome/peroneal nerve involvement.
On November 8, 2010, the worker was seen for a medical assessment by a WCB sports medicine consultant. The worker provided further details surrounding the mechanism of injury of May 26, 2010. The worker noted that a hog weighing 280 to 300 pounds ran off the truck and struck him on the medial aspect of the right calf. His leg was planted at the time and the collision caused a varus stress into his right knee. He felt a pop as well as immediate pain into the right calf and knee area. The following opinion was formed after the assessment:
The clinical presentation was most consistent with a right lateral collateral ligament tear. This was in light of the mechanism of injury which involved varus stress through the knee, the documented pop sensation during the injury, the clinical evidence of LCL laxity, perception of shooting pain down the lateral leg consistent with a possible peroneal neuropraxia, and the noted effusion on knee x-ray early in the presentation. The subsequent swelling into the calf was likely due to knee effusion in the knee and due to gravity would cause edema into the lateral compartments of the calf. Normal MRI and bone scans of the lower right leg offer further evidence of the normal anatomy of those structures.
On the balance of probabilities, the worker's current presentation appeared to be medically accounted for in relation to the workplace injury. Treatment for a clinically evident LCL tear would be bracing for four to six weeks….there was no evidence of a pre-existing condition that may be materially contributing to a delay in the worker's recovery. Given the mechanism of injury and the likelihood of peroneal neuropraxia in midst of an LCL tear, the upcoming nerve conduction study would be reasonable, however would not be medically necessary as it would not change the medical management of the condition.
On November 29, 2010, a neurologist wrote to the treating physician to advise that based on nerve conduction study findings, there was no evidence of neuropathy affecting the right lower leg on testing. This did not exclude a minor nerve compression. Clinically, the numbness in the second and third toes could be related to a more distal problem within the foot, and may be related to the abnormal mechanics of his walking due to the knee pain. The worker's most significant problem was orthopaedic, related to the knee.
The worker had an MRI of the right knee on January 16, 2011 which showed the following findings:
1. Attenuation distal lateral collateral ligament consistent with a tear and some healing.
2. Complex tear medial meniscus.
On January 25, 2011, the worker's orthopaedic surgeon recommended a right knee arthroscopy to repair the meniscal tear.
On February 7, 2011, the WCB sports medicine consultant reviewed the file and stated that the medial meniscus tear would not be related to the workplace injury but rather was due to degenerative changes. He noted that the early medical reports by the worker's treating health care providers suggested lateral knee and leg pain and there were no reports of medial knee pain. There was no noted joint line tenderness, Apleys testing and McMurray's testing was negative at the call-in examination. He noted that based on the MRI findings, the para-meniscal cyst and the secondary osseous changes suggesting chronic changes rather than acute or subacute injury, it was probable that these changes represented a pre-existing condition rather than an injury related to the workplace accident.
On March 25, 2011, the WCB sports medicine consultant noted to the file that the worker had recovered from his compensable LCL injury.
On April 8, 2011, a decision was issued to the worker that in the opinion of the WCB, he had recovered from the effects of his accepted diagnosis of a right lateral collateral ligament tear and that the medial meniscus tear was not related to the May 26, 2010 injury. On October 31, 2011, the worker appealed the decision through the Worker Advisor Office and submitted that the medial meniscus tear was related to the compensable injury.
On December 9, 2011, Review Office confirmed that the worker's right medial meniscus tear was not causally related to his compensable injury of May 26, 2010. Review Office was of the opinion that the mechanism of injury, the reported clinical findings and the worker's complaints were not consistent with a right medial meniscus tear. Review Office accepted that the worker had a varus force (stress applied to the medial side of the knee) type injury to his right knee. It accepted the opinion of the WCB sports medicine consultant dated February 7, 2011. On January 30, 2012, the worker advisor appealed Review Office's decision to the Appeal Commission and a hearing was held on February 28, 2012.
Following the hearing and discussion of the case, the appeal panel requested additional information from the orthopaedic surgeon who performed surgery on the worker's knee on April 12, 2011. The requested information was later received and was forwarded to the interested parties for comment. On April 3, 2012, the panel met further to discuss the case and render its decision.
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.
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 4(1) provides:
4(1) Where, in any industry within the scope of this Part, personal injury by accident arising out of and in the course of the employment is caused to a worker, compensation as provided by this Part shall be paid by the board out of the accident fund, subject to the following subsections. (emphasis added)
The key issue to be determined by the panel deals with causation and whether the worker’s right meniscus tear arose out of and in the course of his employment.
Worker's position:
The worker appeared at the hearing accompanied by a worker advisor. The worker's position was that his right medial meniscus tear was related to the May 26, 2010 compensable injury. It was submitted that the worker did not have any right knee difficulties prior to the workplace accident and was able to perform his duties as a livestock handler. At the time of the injury, the worker heard a pop and felt immediate pain in his right leg and knee that was made worse by activity. It was also noted in the first doctor's report that the worker felt right knee pain when his foot was rotated. According to medical literature, these are all clinical signs of a meniscal tear. Although during the call-in examination the WCB medical advisor did not observe any particular problems with the worker's right knee, the neurologist who saw the worker twenty-two days later believed the most significant problem was orthopaedic related to the knee. It was therefore submitted that there was evidence to support, on a balance of probability, a causal relationship between the worker's right medial meniscus tear and the May 26, 2010 injury.
Analysis:
The issue before the panel is whether or not the worker's right meniscus tear is related to the compensable injury of May 26, 2010. In order for the worker's appeal to succeed, the panel must find that the workplace accident of May 26, 2010 caused the worker to suffer a tear to his right medial meniscus. On a balance of probabilities, we are not able to make that finding.
At the outset, the panel notes that the appeal before us deals with the very limited issue of whether the medial meniscal tear was sustained in the workplace accident of May 26, 2010. The panel acknowledges the worker's evidence at the hearing that he has had ongoing right calf issues for which he has been referred to a pain specialist for further treatment. This decision is limited to consideration of whether the meniscal tear is compensable. We make no comment regarding whether the worker's ongoing right calf issues are compensable.
In order for the panel to find that the worker's right medial meniscal tear was sustained when he was struck by the hog, there would have to have been some medical findings in the early medical reports suggestive of this injury. We find that such findings are minimal. Although the worker reported hearing a snap noise coming from his right knee, the medical reports document that his complaints of pain were on the lateral side of the knee. There were no reports of medial knee pain. The biggest evidentiary challenge for the worker's appeal is the call-in examination of November 8, 2010. At that time, the WCB medical advisor specifically examined the worker's knee and the usual tests for a meniscal tear, that included joint line tenderness, Apley's and McMurray's, were all negative.
The WCB medical advisor's memo of February 7, 2011 specifically considered whether the diagnosis of medial meniscal tear could be related to the compensable injury and concluded that it was probable that the meniscal tear found on MRI represented a pre-existing degenerative condition rather than being related to the compensable injury. Following the hearing, the panel obtained copies of the orthopaedic surgeon's operative report of April 12, 2011. It also noted degenerative type changes in the knee. There is no other medical report on file which suggests a different etiology for the meniscal tear, or in particular an acute or traumatic tear.
In view of the foregoing, the panel concludes, on a balance of probabilities, that the worker's right meniscus tear is not related to the compensable injury of May 26, 2010. The worker's appeal is therefore dismissed.
Panel Members
L. Choy, Presiding OfficerA. Finkel, Commissioner
P. Walker, Commissioner
Recording Secretary, B. Kosc
L. Choy - Presiding Officer
Signed at Winnipeg this 16th day of May, 2012