Decision #177/06 - Type: Workers Compensation

Preamble

An appeal panel hearing was held on August 24, 2006, at the request of a worker advisor, acting on the worker’s behalf. The panel discussed this appeal following the hearing on August 24, 2006 and again on September 27, 2006.

Issue

Whether or not the claim is acceptable.

Decision

That the claim is acceptable.

Decision: Unanimous

Background

On January 22, 2003, the worker, a clinical resource nurse, filed a claim for compensation with the Workers Compensation Board (WCB) for difficulties that she was experiencing with her right wrist and fingers. The worker described her difficulties as follows:

“Repetitive work. I remove tubes from patients arteries daily. When I pull the tube out, I have to stand there and apply pressure with my right hand, in order to stop the bleeding. Some days I stand there for a long period of time, in order to stop the bleeding. I also scrub in for O.R. procedures. I was diagnosed with carpal tunnel syndrome in July, 2002 to my right wrist. I have been having pain and numbness in my right wrist throughout the year 2002. The pain and numbness increased in Sept. 2002. I have been trying to compensate for the numbness, so now I am having problems with my right thumb. Currently three of my fingers are completely numb. I am unable to work. I am right hand dominant.”

The worker advised that her last day of work was January 21, 2003 and that her doctor told her to be off work until March 4, 2003 at which time he would decide whether or not she should see a specialist.

The attending physician reported that the worker was assessed on January 21, 2003 with complaints of pain in her hand, poor grip strength and numbness. The diagnosis rendered was right carpal tunnel syndrome (CTS) and right tenosynovitis.

In e-mail correspondence to a WCB adjudicator on January 28, 2003, an employer representative stated that he spoke with the worker’s supervisor to discuss the job activities which had been reported to have caused the worker’s right wrist, hand and thumb difficulties. The supervisor advised that the worker attributed her daily work activities of removing catheters and applying pressure with the right hand for 15 minutes at a time as the cause of her symptoms. She said the worker had been experiencing these symptoms for some time now and that the symptoms had recently increased and included numbness in her hand. The employer representative further noted that according to their records, the worker suffered a previous fracture of her right wrist in 1984 and it was not clear what relationship, if any, this may have had on the development of her condition.

The WCB adjudicator spoke with the worker on February 3, 2003 and the following information was obtained:


  • she was a permanent, 29 year, full time employee with the accident employer. She developed right wrist problems sometime in July of 2002;
  • there was no one specific accident or incident to account for her symptoms;
  • there were no changes in her work duties or increases in her work load;
  • she returned to full time regular duties on August 6, 2002 and within a week, she started to have problems with numbness in her baby finger, ring finger and middle finger. She was not experiencing any discomfort in her left wrist or hand area;
  • she did not seek ongoing medical treatment and was hoping that her symptoms would improve on their own.
  • things did not improve and on completion of her shift on January 21, 2003 she attended a doctor for treatment. At this time there were no new accidents or incidents at work nor changes to her job duties;
  • she was now having problems with her left wrist and hand due to over using it as a result of her right hand injury;
  • her work duties involved tearing packages (50 packages per procedure, 8 to 10 procedures per shift), opening and assembling various sterile items onto trays, filling syringes, applying pressure when removing tubes, and changing IV bags. The worker said there was a great deal of gripping involved, applying pressure and having her right wrist exposed to different angles throughout the course of a typical shift;
  • she has never been diagnosed with diabetes, hypothyroidism or rheumatoid arthritis in the past. She smoked a ½ package of cigarettes per day for the past 25 years.

     

In a report to the WCB dated February 5, 2003, a plastic surgeon outlined his examination findings of the worker as follows:

“…she had decreased sensation in the median nerve distribution and acutely positive Tinel’s sign and positive Phalen’s. There is no muscle wasting at this time but she has sensory changes which she states are constant all day long. The patient has had a nerve conduction study yesterday which shows mild median neuropathy (CTS) and no evidence of ulnar neuropathy. The patient’s contralateral left hand is not problematic to her. …The patient as well has presented with acute trigger thumb, right which is again an overuse type of synovitis.”

Following consultation with the WCB’s healthcare services branch, the worker was advised on February 11, 2003, that her claim for compensation had been denied. After a review of the file evidence including work activities, non-work related risk factors and the WCB medical advisor’s opinion, the adjudicator could not establish a relationship between the worker’s right wrist and thumb difficulties to an accident as defined in subsection 1(1) of The Workers Compensation Act (the Act).

In a letter to the WCB’s Review Office dated February 19, 2003, the worker appealed the above decision. She stated:

“The initial error made by your adjudicator, was never making an on site assessment of my job duties. Specifically my job entails using a twisting motion to undo catheters from tubings that have been cemented on with contrast. Drawing up fluids in pressurized syringes where excessive force must be used. Opening and closing forceps. Removing arterial lines range from 4-11 fr. Applying continuous pressure to the artery to obtain hemostasis, this at times requires 30 minutes of constant pressure with a flexed wrist. When you are finished, your hand is so cramped you must use your opposite hand to straighten out your fingers. I push stretchers, lift patients. Now repeat this process 6-10 times everyday. Because we use radiation you must do all these activities while wearing 20-30 pounds of protective lead…”.

In a submission dated April 7, 2003, the employer’s representative outlined his position that there was insufficient evidence to establish a causal connection between the worker’s work activities and the development of her condition. He pointed out that work factors associated with the development of CTS included a combination of repetitive and forceful movements of the hand and wrist and that the worker’s described duties did not meet this standard. He noted that many work activities did involve repetitive hand/wrist movements to some extent but that, in itself, did not necessarily predispose an individual to the development of CTS. He stated that co-workers who carry out comparable duties have not experienced similar difficulties which made such a causal connection even more dubious.

Prior to considering the worker’s appeal, Review Office sought medical advice from a WCB orthopaedic consultant on April 11, 2003. The consultant confirmed that right CTS and right stenosing tenosynovitis was the diagnosis of the worker’s condition. He said that activities inside and outside of employment may cause these conditions to be symptomatic. He did not feel, however, that the worker’s described employment activities lent themselves to the development of these conditions.

A report was received from an occupational health physician dated April 11, 2003. The physician stated, in part, that he was familiar with the hand and upper extremity ergonomics and injuries experienced by nurse technicians doing vascular studies. He stated that the worker’s job tasks “…involve biomechanical loading of the musculotendinous structures of her right hand, thumb and wrist in particular, applying finger pressure over the artery puncture sites for prolonged periods with a lot of flexor forces with the wrist in extended position. This positioning directly applies pressure over the carpal tunnel. The thumb flexion forces frequently used injecting catheter balloons and contrast dye are near maximal static forces for a strong woman, generating significant strain on the flexor tendon and increasing carpal tunnel pressures, developing of thumb flexor tenosynovitis leading to her trigger thumb is quite plausible without an incident injury event. By my assessment these forces are sufficient to cause carpal tunnel syndrome and trigger thumb; her diagnoses are work related injury conditions.”

On April 17, 2003, Review Office determined that the claim was not acceptable based on the following findings:

  • the employment activities of a clinical resource nurse were not highly repetitive and did not require high repetition involving full flexion and extension. Although there was some force involved, it was not done on a repetitious fashion;
  • the worker’s employment activities involved a minimum of mechanical stress and force.
  • the job duties of a clinical resource nurse was not causal for the development of right CTS and tenosynovitis;
  • certain aspects of the worker’s job duties would make CTS/tenosynovitis more symptomatic, but this did not constitute an ‘aggravation’ or ‘personal injury by an accident’ arising out of and in the course of the worker’s employment as required by legislation for acceptance of a claim;
  • the worker had significant risk factors that predisposed her to develop CTS.

On August 24, 2006, an oral hearing was convened. During the course of the oral hearing, the worker provided an extensive description of her job duties which involved assisting in angiogram and angioplasty procedures. She indicated that on many days, her first job duty would be to rip open up to five hundred packages using her thumbs and hands. She would hold the package with her left hand and peel it open using her right thumb and hand. This task would generally last between thirty and forty-five minutes.

The worker also indicated that she was generally involved in between eight and ten cases a day. On average, two to three of these cases would be angioplasties. For each angioplasty, four to six catheters would have to be filled with the worker often being responsible for that task. The time between filling each catheter would be less than five minutes. The filling often took between thirty seconds and two minutes. The worker testified that significant and sustained pressure was placed upon her right hand both in loading the syringe as well as in depressing the plunger on the syringe in order to fill the catheter. In particular, she indicated that her duties involved

  • loading relatively large syringes with a viscous fluid by drawing upon the plunger using her right thumb as well as her right index and middle finger;
  • inflating balloons (catheters) by pushing forcibly onto the plunger of the syringe using the palm of her right hand with her wrist extended.

The worker testified that in filling for some balloons an “awful lot more force” was required.

“Like if you were putting a balloon in your aorta, which would be about . . . 30 millimeters in diameter for this balloon, it takes a lot of force to fill up that balloon . .If I filled it up, you could stand on it and it wouldn't break.”

In terms both of angiograms and angioplasties, the worker noted that “at the end of the procedure, you'd have to hold the puncture site, which requires a lot of force.” In general, she indicated that the puncture would be located in the femoral artery over the head of the femur.

“You may have to hold for an hour. And even though your hand is cramped, you can't say, ‘you know what, I'm going to come back’, because once you start you can't move your fingers.”

In describing the application of pressure, the worker indicated that the pressure was being applied with her right fingers on the puncture with her right wrist fully extended. She suggested that she often used her upper body strength as well as her other hand to apply sufficient pressure. The minimum amount of time the pressure would be applied would be about eight to ten minutes. The maximum would be an hour and a half. On any shift, all eight to ten cases would need to be held. If there were only two nurses on shift, then the worker would have to hold about fifty percent of the punctures.

In reflecting upon when her injury became more painful, the worker suggested it “was more the holding the puncture sites that made it worse, as opposed to inflating balloons.”

In terms of actions involving fine motor skills, the worker noted she was required to rewind the minute wires involved in the angiogram. She also indicated that in clean up, she would have to use a squirt bottle. She noted that the triggering motion of the squirt bottle “just kills me. I'll have instant numbness of my hand.”

In the course of her testimony, the worker indicated that she was not diabetic.

In argument, the worker's representative noted that according to a WCB medical advisor, the workplace factors associated most closely with the development of CTS include a combination of force and repetition, force and posture and/or hand wrist vibration. He asked the panel:

“on a balance of probabilities, which is more likely, that the documented repetitive, forceful and awkward movements that our client uses in her workplace duties have caused her CTS, or that some unknown factor has caused the CTS in her right arm only…”.

The employer's representative took the position that “there is insufficient evidence to confirm a cause and effect relationship with work and the development of the CTS or the tenosynovitis.” She noted that apart from her work, the worker had other risk factors related to CTS and tenosynovitis with the number one risk factor being her gender. The employer's representative also indicated that middle age and smoking were other risk factors which made the worker more likely to suffer from CTS. She suggested that the cause of the injuries could be idiopathic.

Following the hearing, the appeal panel wrote to the employer’s advocate and asked for a copy of the Mayo Clinic literature she referred to that related to “Stenosing Tenosynovitis”. On September 12, 2006, the worker advisor was provided with a copy of the literature. On September 27, 2006, the panel met to render its final decision.

Reasons

Section 4(1) of the Workers Compensation Act provides that:

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.

The parties are in agreement that the worker has been experiencing difficulties with her right thumb wrist and fingers which have been diagnosed as right carpal tunnel syndrome and right tenosynovitis. The parties are also in agreement that the work activities most strongly associated with CTS include a combination of both repetitive and forceful movements of the hand. The WCB medical advisor in his February 10, 2003 memo and the occupational health physician also respectively place emphasis upon force and posture or the application of force at extended positions as workplace factors more strongly associated with CTS.

At issue is whether the injuries experienced by the worker arose out of and in the course of her employment. The worker argues, on a balance of probabilities, that the most likely cause of her injury is the “repetitive, forceful and awkward movements” associated with her workplace duties. In terms of the CTS, particular emphasis is placed upon the application of pressure to puncture sites as well as the filling of catheters with the viscous fluid. With regard to the tenosynovitis, the worker suggests that the thirty to forty-five minute procedure related to ripping open packages is the most likely cause.

The worker's argument is supported by the opinion of the occupational health physician who considered both her CTS and tenosynovitis to be work related injuries as well as by the views of the plastic surgeon who noted that that the worker “. . . has presented with acute trigger thumb, right which is again an overuse type of synovitis.”

The employer suggests that there is insufficient evidence to establish that the injuries arose out of and in the course of the employment. She notes that the worker's gender was a particularly significant risk factor in terms of tenosynovitis as well as CTS. She observes that age and smoking also were significant risk factors for the worker with regard to CTS. The employer's views are also supported by a considerable body of medical opinion on the file.

Taking into account the evidence as a whole, the panel finds, based upon a balance of probabilities that the worker's injuries arose out of and in the course of her employment. In making this decision, the panel places particular weight upon the careful review of the worker's job duties which was undertaken during the course of the oral hearing.

The panel notes that CTS is mostly closely associated with highly repetitive activities involving a considerable application of force and least closely associated with activities that do not involve either a significant amount of force or a significant amount of repetition. We note that force and posture or the application of force at extended positions have also been respectively identified by a WCB medical advisor and the occupational health physician as being more strongly associated with CTS.

In finding, based upon a balance of probabilities, that the right hand CTS arose out of and in the course of the worker's employment, the panel places heavy emphasis on the worker's description of the nature of her duties in applying pressure to punctures.

The panel notes that these procedures involved a considerable amount of force being applied at full extension of the visit. Generally, the worker would be expected to conduct this procedure four or five times a day with a minimum duration of eight minutes and a maximum duration of ninety minutes. At times, the worker would have to stand on a stool to apply sufficient force. The panel also notes that in filling the syringe and inflating the catheter a considerable amount of force at full extension was also involved. This procedure was undertaken between four and six times for each angioplasty. The worker was frequently responsible for this procedure.

While the work undertaken does not appear to be of a particularly high volume, the panel notes that it often involved the application of a considerable amount of force over a considerable period of time with the right wrist fully extended. Considering the evidence as a whole, the panel finds, based upon a balance of probabilities, that the worker's right hand CTS arose out of and in the course of her employment. While the worker may have had other risks factors such as gender, age and smoking, the panel finds, based upon a balance of probabilities that the worker’s injuries arose out and in the course of this significant application of force at full extension.

The panel notes that the pain associated with the worker's CTS appeared to increase after she applied pressure to the punctures. We also observe that the discussion of the worker's workplace duties was more extensive during the oral hearing than the information which would have been available to the medical advisors whose opinion was relied upon by the employer.

In finding, based upon a balance of probabilities, that the right thumb tenosynovitis arose out of and in the course of the worker’s employment, the panel places particular weight upon the worker's description of her duties in ripping open the up to five hundred packages. Based upon a balance of probabilities, the panel considers that the gripping and ripping of the packages over an extended period of time was the cause of the right thumb tenosynovitis. The panel notes that our views are supported by the plastic surgeon and the occupational health physician.

Based upon a balance of probabilities, the panel finds that the claim is acceptable. The appeal is allowed.

Panel Members

B. Williams, Presiding Officer
A. Finkel, Commissioner
M. Day, Commissioner

Recording Secretary, B. Kosc

B. Williams - Presiding Officer
(on behalf of the panel)

Signed at Winnipeg this 15th day of November, 2006

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