The Appeal CommissionThe Workers Compensation Act of Manitoba

Preamble

An Appeal Panel hearing was held on April 18, 2005, at the request of a worker advisor, acting on behalf of the worker. The Panel discussed this appeal on the same day.

Issue

Whether or not responsibility should be accepted for the worker's right carpal tunnel syndrome, associated surgery and time loss in relation to the October 30, 2002 compensable right thumb injury.

Decision

That responsibility should not be accepted for the worker's right carpal tunnel syndrome, associated surgery and time loss in relation to the October 30, 2002 compensable right thumb injury.

Decision: Unanimous

Background

On October 30, 2002, the worker was lifting parts from a tray (6" x 18" 10 lbs.) during his employment activities as a warehouseman when the parts accidentally slipped and landed onto his right thumb. Subsequent medical reports revealed the following:

• October 30, 2002 - a hospital emergency report stated that a 10 lb. weight fell onto the worker's right thumb at the MCP joint. No fracture or dislocation was identified and a plaster glutter splint was applied. The diagnosis rendered was a contusion right thumb.
  
  
• November 1, 2002 - an orthopaedic specialist noted that x-rays showed the presence of osteoarthritis of the MCP joint and there was also a possible fracture at the neck of the 1st metacarpal which was slightly impacted. The specialist suggested a thumb spica cast due to the amount of tenderness and pain experienced by the worker. This was later carried out.
  
  
• November 13, 2002 - right hand x-rays revealed degenerative changes at the MPC joint and CMC joint. Two well corticated bony fragments were noted in relation to the 1st CMC joint. No recent fractures were identified.
  
  
• November 13, 2002 - the treating orthopaedic specialist stated that the worker's cast was removed and that he still had swelling and tenderness around the MCP joint. Due to tenderness, the specialist stated that the worker would be given a new thumb spica cast.
  
  
• November 29, 2002 - right hand x-rays were compared to the study of November 13, 2002. There was a slight deformity at the first MCP joint. The appearance suggested an old fracture. No acute fracture was identified. Degenerative changes were present in the IP and MCP joints as well as the first metacarpal joint.
  
  
• December 10, 2002 - a physiotherapist noted that the worker had pain in his thumb and hand and was still in a splint.
  
  
• January 7, 2003 - the treating physiotherapist advised a WCB case manager that she had not seen the worker for a couple of weeks. She stated that the worker had a prior fracture several years ago and that the thumb wasn't normal to begin with so he will not end up with full function.
  
  
• January 7, 2003 - the treating physiotherapist advised the family physician that the worker's range of motion had plateaued and was at pre-injury level according to the worker. Strength remained poor and was restricted by pain. The therapist noted that the worker was still off work and complained of nocturnal numbness.
  
  
• January 10, 2003 - x-rays of the right thumb showed degenerative changes with no recent fractures identified.
  
  
• January 10, 2003 - the treating orthopaedic specialist reported that the worker still had some weak grip strength and discomfort but had made a great improvement. Range of motion was pre-injury. The specialist noted that the worker was going for physiotherapy and that x-rays showed that the fracture had healed in an adequate position. Light duties were suggested for six weeks and a graduated return to normal duties over four weeks.
  
  
• March 6, 2003 - the family physician reported that the worker complained of pain in his right thumb after hitting a door at home. The worker had tender swelling at the MP joint. Recovery was incomplete. On March 7, 2003, the family physician noted joint thickness and some deformity at the MP joint. There was no tenderness and good movements. He stated that the worker could return to regular duties by March 10, 2003.
  
  
• March 17, 2003 - the family physician stated that he arranged for the worker to undergo nerve conduction studies (NCS) as the worker complained of progressive numbness in the tips of his thumb, index and middle fingers.
  
  
• March 12, 2003 - NCS revealed severe right carpal tunnel syndrome (CTS) and evidence of minimal to mild left CTS.
  
  
• March 27, 2003 - the family physician noted that after the worker's right thumb cast was removed, he developed numbness in the tips of his thumb, index and middle fingers one month later and that his hand falls asleep at night. Surgery for carpal tunnel to the right wrist was suggested.

In a letter dated April 2, 2003, a WCB case manager noted that the worker was missing time from work because of increased pain in his thumb after hitting it against a door at home and because of pain and numbness in the right thumb and fingers which the family doctor suggested was because of CTS. The case manager stated that the evidence did not suggest that his recent time loss was related to the October 30, 2002 workplace injury.

• April 19, 2004 - the family physician responded to a letter that was written to him by a worker advisor. The physician stated that the worker believed the numbness and weakness of his right hand started at the time of the thumb fracture which was treated in a cast last fall. Since then, the worker had numbness in the distribution of the median nerve, occurring night and day. The worker agreed to proceed with surgery on July 4, 2003 which resulted in total resolution of his presenting complaint. The family physician concluded his report by stating "…from the sequence of history as related by this patient long considered to be an honest, truthful, reliable individual, on the basis of probability, I must assume that the second cast although doubtlessly well applied must somehow have impinged on the underlying median nerve causing his neuritis complaints."
  
  
• July 19, 2004, a WCB medical advisor requested additional information in order to respond to questions posed by primary adjudication. These included x-ray reports of the right thumb and wrist dated April 14, 2004 and reports from the Health Sciences Centre.
  
  
• October 20, 2004 - a WCB medical advisor reviewed the file information and stated, in part, "on balance, is not probable that crush injury to R thumb is responsible for CTS, nor is the treatment (cast immobilization). Thus, the opinion would remain the same."

On November 8, 2004, the worker was advised by his case manager that no change would be made to the WCB's decision of April 2, 2003 based on the comments expressed by the WCB medical advisor on October 20, 2004. On November 23, 2004, a worker advisor appealed this decision to the Review Office. The worker advisor asked Review Office to consider the opinion expressed by the family physician dated April 19, 2004 along with the WCB's policy 44.10.80.40 Further Injuries Subsequent to a Compensable Injury. The worker advisor argued that since the worker continued to have symptoms and continued to work until his surgery, the WCB should accept responsibility for the surgery and the subsequent period of convalescence to recover from the surgery. Should Review Office only accept the WCB medical advisor's opinion, the worker advisor felt that a Medical Review Panel (MRP) was warranted due to the difference in medical opinions.

• December 8, 2004 - the Review Office asked a WCB orthopaedic consultant to review the file information and to comment on the case. The consultant's response to Review Office is dated December 9, 2004.

In a decision dated December 9, 2004, Review Office determined that no responsibility should be accepted for the worker's right CTS surgery and associated time loss in relation to the compensable right thumb injury of October 30, 2002. Following its review of the file information, Review Office was unable to establish that the worker's CTS was caused by the work accident of October 30, 2002 or from its related treatment. Review Office noted that the October accident only involved the right thumb and there was no documented evidence of any right wrist injury. The NCS performed in March 2003 showed evidence of CTS in both wrists. If the immobilization/casting was causal for the right CTS, Review Office was unable to explain the development in the opposite wrist. Review Office also considered the opinions of three WCB medical consultants who stated there was no relationship between the CTS and the compensable injury as neither the injury nor the cast would entrap the median nerve at the wrist level.

With respect to the issue concerning an MRP, a WCB sector manager wrote to the worker advisor on January 17, 2005, stating that the requirements of subsections 67(1) or 67(4) of The Workers Compensation Act (the Act) had not been met and that the request for an MRP was denied.

On February 15, 2005, the worker advisor appealed Review Office's decision of December 9, 2004 and an oral hearing was convened.

Reasons

The Panel was asked to determine whether responsibility should be accepted for the worker's right CTS, associated surgery and time loss in relation to the October 30, 2002 compensable right thumb injury. For this appeal to be accepted the Panel would have to find that the CTS is causally related to the right thumb injury. The Panel was not able to find a relationship between the CTS and right thumb injury and accordingly the appeal is declined.

Evidence and Argument at Hearing

The worker attended the hearing with a worker advisor who made a presentation on his behalf. The worker answered questions posed by his representative and by the Panel.

The employer was represented at the hearing by an advocate and a staff rehabilitation specialist. The advocate made a presentation on behalf of the employer.

The worker described the accident. He advised that he hurt his right thumb but did not hurt his wrist. He also advised that he did not have problems with his hands before this accident. He also described the various braces and casts that he wore. He confirmed that his wrist was held in a flat position in the casts and braces. He also confirmed that he did not have any problems with his wrist or numbness until after the cast was removed. He described his right wrist symptoms and advised that he had surgery on his wrist and has had no problems since. He also advised that he has not had any problems with his left hand or wrist.

The worker advisor noted that the worker was asymptomatic of CTS prior to the October 30, 2002 injury and did not develop right hand symptoms until after the second cast was removed. She referred the Panel to WCB Board of Director's Policy 44.10.80.40 which deals with further injuries subsequent to a compensable injury. She noted that this policy provides that a further injury which arises from the delivery of treatment for the original injury is compensable. It was suggested that the cast for the right thumb might have caused the CTS. While acknowledging they do not know what specifically triggered the onset of the worker's right hand symptoms, they believe the facts support a logical conclusion of a cause/effect relationship to the right thumb injury.

The employer's advocate noted that the worker has been diagnosed with bilateral CTS. She referred to the opinion of the WCB medical advisors that the injury to the worker's right thumb and related treatment would not contribute to the worker's severe CTS and the need for surgical release. She submitted that the evidence does not support a relationship between the right thumb injury and the worker's CTS.

Analysis

After a careful review of the evidence including the evidence provided by the participants at the hearing, we find on a balance of probabilities that there is no relationship between the worker's workplace thumb injury and his right CTS. Responsibility should not be accepted for the worker's right CTS and the related surgery and time loss.

In arriving at this conclusion we rely upon the following evidence:

• Nerve Conduction Studies confirm the worker has bilateral CTS. This supports the position that the right CTS was not caused by the workplace injury or its medical treatment. No cast or other treatment were applied to the worker's left hand yet it has been diagnosed with CTS.
  
  
• The symptoms related to CTS were not present until after the cast was removed. The worker's evidence was that he had no symptoms regarding the wrist or pressure points at the wrist or numbness or tingling of the fingers innervated by the median nerve while wearing the cast.
  
  
• WCB medical advisor reviewed the file and concluded that "on balance, it is not probable that crush injury to right thumb is responsible for CTS nor is the treatment (cast immobilization)."
  
  
• WCB orthopaedic consultant reviewed the file and commented that there is not a cause and effect relationship between the treatment for the thumb injury and the CTS. He stated "A thumb spica cast would not impinge on or entrap the median n (nerve) within the carpal tunnel. He also has mild CTS in the opposite L hand not involved in the C.I. In my opinion there is no relationship between the CTS and CI of October 30/02 as neither the injury or cast would entrap the median n. (nerve) at the wrist level."

The worker's appeal is declined.

Panel Members

A. Scramstad, Presiding Officer
A. Finkel, Commissioner
M. Day, Commissioner

Recording Secretary, B. Miller

A. Scramstad - Presiding Officer
(on behalf of the panel)

Signed at Winnipeg this 19th day of May, 2005