WORKPLACE SAFETY AND INSURANCE APPEALS TRIBUNAL DECISION NO. 845/15

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1 WORKPLACE SAFETY AND INSURANCE APPEALS TRIBUNAL DECISION NO. 845/15 BEFORE: S. Netten: Vice-Chair HEARING: April 28, 2015 at Toronto Written DATE OF DECISION: June 3, 2015 NEUTRAL CITATION: 2015 ONWSIAT 1201 DECISION UNDER APPEAL: WSIB Appeals Resolution Officer decision dated January 9, 2014 APPEARANCES: For the worker: For the employer: Interpreter: J. Johnson, Paralegal Not participating None Workplace Safety and Insurance Appeals Tribunal Tribunal d appel de la sécurité professionnelle et de l assurance contre les accidents du travail 505 University Avenue 7 th Floor 505, avenue University, 7 e étage Toronto ON M5G 2P2 Toronto ON M5G 2P2

2 Decision No. 845/15 REASONS (i) Issue [1] The issue under appeal is entitlement for right shoulder arthroscopic decompression surgery of May 2, (ii) Overview [2] The worker, a company truck driver, was granted entitlement for a right shoulder strain sustained upon removing a strap which caught, causing sharp shoulder pain, on June 12, He returned to modified duties, followed by regular duties from September 4, Entitlement was subsequently extended, in December 2012, to include a thin partial thickness supraspinatus tear. Entitlement for shoulder surgery, recommended in March 2013, was denied on the basis that it was not required as a result of the workplace injury. [3] The worker s objection to this determination was denied at the appeals level of the Board in January 2014, and the worker appealed to the Tribunal. This appeal was selected for a written hearing pursuant to the Tribunal s Practice Direction on Written Appeals. In written submissions dated February 25, 2015, the worker s representative notes that the worker had no prior right shoulder impairments, argues that there is a relationship between the partial thickness tear and the impingement syndrome, and requests consideration of the benefit of the doubt. (iii) Law and Policy [4] The Workplace Safety and Insurance Act, 1997 ( WSIA ) applies to this appeal. All statutory references in this decision are to the WSIA, as amended, unless otherwise stated. Section 126 requires the Tribunal to apply Board policy when making its decisions. [5] Entitlement to health care is governed by section 33: 33(1) A worker who sustains an injury is entitled to such health care as may be necessary, appropriate and sufficient as a result of the injury [6] Tribunal jurisprudence applies the test of significant or material contribution to questions of causation. A significant or material contributing factor is one of considerable effect or importance. It need not be the sole contributing factor. [7] The standard of proof applicable in workers compensation proceedings is the balance of probabilities. Pursuant to section 124(2), the benefit of the doubt is given to the claimant in resolving an issue where the evidence for and against is approximately equal in weight. (iv) Evidence [8] The worker had been hired in His regular duties were outlined in chart notes as requiring the strapping of cars on and off his truck, four truck loads daily, each with nine cars, and each car with four straps. The worker described his injury in the Worker s Report of Injury dated June 25, 2012, as follows: I was removing a tire strap from vehicle on the trailer and the strap caught between the tire and fender causing a sharp pain in my right shoulder.

3 Page: 2 Decision No. 845/15 [9] Clinical notes from the worker s family doctor, Dr. S. Rahman, were provided from June 2010 to September The first mention of the shoulder is on June 12, 2012, the date of injury, at which time Dr. Rahman assessed a likely strain. She wrote RC injury when the worker returned on June 14, 2012 with complaints of difficulty lifting, pulling and shifting gears. The worker was referred for physiotherapy. [10] On June 19, 2012, physiotherapist P. Ho noted limited shoulder flexion and abduction, a positive empty can test (for the supraspinatus tendon), and tenderness of the infraspinatus, teres minor and supraspinatus. [11] On June 28, 2012 Dr. Rahman s notes indicate that the worker s pain was not much better. She completed a Functional Abilities Form (FAF) stating that the worker was unable to lift arm overhead or lift any weight with R arm/shoulder. A right shoulder ultrasound of July 4, 2012 identified a possible small partial-thickness tear in the right supraspinatus, with the rotator cuff and biceps tendon normal and impingement testing was negative. Dr. Rahman noted on July 16, 2012 that the worker was 50% better, still on modified duties, and abduction and internal rotation were better. An MRI of July 26, 2012 found mild tendinosis of the supraspinatus tendon with a thin linear interstitial partial thickness tear, as well as mild osteoarthritis of the acromioclavicular (AC) joint. [12] On August 9, 2012, Dr. Rahman noted that the worker could abduct to 110 degrees without pain, and internal rotation was also improved. The worker continued with physiotherapy. Her FAF that day indicated that the worker could not do overhead activities or lifting due to right rotator cuff tendonitis/tear. Dr. Rahman s FAF of August 27, 2012 stated that the worker was capable of returning to work with no restrictions. Her chart note for that day states: right shoulder much better wants to go back to work full duties ROM improved no no [sic] pain [13] However, on September 27, 2012 Dr. Rahman noted that the worker had increased pain after returning to regular duties, and his abduction was restricted to 90 degrees. She reinstated work restrictions on overhead activities, pushing, pulling and lifting, noting aggravation of previous injury. She wrote a letter that day: [The worker] sustained a right shoulder injury while at work on June 12 th, He was on modified duties from then until the end of August. He was undergoing physiotherapy and medical treatment and was overall much better before he re-started work on full duties After returning to physical work for approximately a week, his shoulder pain has returned (same as before). This is likely an aggravation of his previous injury and not a new injury. He has been referred to the surgeon, appointment pending. He has been advised to continue physiotherapy in the meantime. [14] The worker saw orthopedic surgeon Dr. S. Haider on November 29, He diagnosed an impingement syndrome and recommended further physiotherapy. [15] Without consideration of Dr. Haider s report (not then on file), the Board allowed entitlement to the rotator cuff tear found on MRI; the memorandum of December 11, 2012 states:

4 Page: 3 Decision No. 845/15 Based on a review of the medical documentation, the worker s current and ongoing right shoulder symptoms appear to be the direct result of the workplace injury Given the accident history, the medical continuity subsequent to the accident, and no evidence of right shoulder issues prior to this incident, the partial thickness tear is a result of the workplace injury. [16] The Case Manager clarified entitlement to the worker verbally on December 11, 2012, noting that the AC joint osteoarthritis was not part of the claim. The worker reported having had a cortisone injection from a sports medicine physician in September 2012, giving him one month s relief, as well as seeing Dr. Haider who suggested six weeks of physiotherapy. [17] In follow-up on February 13, 2013, Dr. Haider recommended more physiotherapy and an MRI, noting possible rotator cuff injury, and referred the worker to upper extremity specialist Dr. C. Smith. Physiotherapy extensions were accepted by the Board up to March 29, [18] Prior to seeing Dr. Smith, however, the worker was assessed by orthopedic surgeon Dr. A. ElMaraghy on March 22, 2013: He has pain in his right shoulder for the last nine months. It is staying the same with time and waking him up at night. There is [sic] no neurological symptoms. On examination, he has good active range of motion, no capsular pattern, no AC joint tenderness or long head of biceps pathology. He has positive impingement signs but a good rotator cuff strength. Superior labral testing is positive. He has no real instability or apprehension. MRI shows diffuse tendinosis of both supraspinatus and subscapularis as well as infraspinatus. The sagittal view shows a type 3 acromion consistent with impingement. he will be a candidate for an arthroscopic rotator cuff decompression. [19] The surgery was expedited by the Board. [20] On April 10, 2013, Dr. Rahman wrote: The pain started immediately after the injury. He has never sustained an injury to his right shoulder or had a problem with his right shoulder before this incident; there was no known pre-existing condition in his right shoulder. He has gone through extensive rehabilitation including physiotherapy, home exercises and a cortisone injection without relief of his symptoms. He has seen a sports medicine specialist as well as 2 orthopedic surgeons. Surgery has been recommended for his condition. Based on medical history, physical examination and investigations, [the worker s] condition is consistent with the injury sustained at work in June [21] The Case Manager sought an opinion on whether the proposed surgery was more related to the pre-existing O/A or in your opinion associated to his June 12, 2012 work related incident. Occupational medicine specialist Dr. S. Somerville responded on April 20, He provided his opinion that the small partial thickness tear was likely an incidental finding unrelated to the workplace accident, and went on to discuss impingement syndrome: Impingement syndrome occurs when the rotator cuff muscles become irritated and inflamed as they pass through the subacromial space beneath the acromion. Narrowing of this space by osteoarthritic spurs, anatomic variations in the shape of the acromion such as type 2 or 3 acromion, calcification of the coracoacromial ligament, or other means can cause impingement. Onset of symptoms may be acute if due to injury or may be gradual if due to degenerative changes. IW s symptoms came on abruptly on date of accident, but there is no evidence of trauma.

5 Page: 4 Decision No. 845/15 The MRI scan is stated to demonstrate a type 2 acromion, while the surgeon indicated IW has a type 3 acromion. Type 2 or 3 acromion refers to an anatomic variant of the normal acromion (which is a bony part of the shoulder). There are three variants of the acromion, namely Types 1, 2 and 3. Type 1 is flat, while Types 2 and 3 are curved. The type of acromion an individual has is basically determined by their genetics. Type 2 and 3 acromions are associated with increased prevalence of impingement and rotator cuff tears. IW likely sustained a simple shoulder strain in the workplace accident. IW s impingement is due to his underlying type 2 or 3 acromion The proposed left shoulder surgery is for IW s impingement syndrome which is a pre-existing condition. [22] Entitlement for the surgery was denied in accordance with this opinion. [23] On May 1, 2013, the worker s physiotherapist W. Hsieh wrote that the worker s right shoulder impingement was due to his tear in his supraspinatus tendon. [24] The operative report is not on file. Dr. ElMaraghy wrote on May 2, 2013 that the worker had a right arthroscopic rotator cuff decompression. He responded to questions from the worker s representative on February 18, 2015: Is there a relationship between the partial thickness tear and the impingement syndrome? A partial thickness rotator cuff tendon tear can be caused by subacromial impingement due to repetitive contact of the supraspinatus tendon with the coracoacromial arch. Did the decompression surgery have any effect on the partial thickness tear? Arthroscopic decompression surgery is performed to treat subacromial impingement by relieving the pressure on the underlying muscle and tendon. This is achieved by shaving the undersurface of the acromion and in some cases removing the outer end of the clavicle. The goal of surgery is to decrease pain and improve shoulder strength. The surgery did not have a direct effect on the partial thickness tear. Is there a reason that the tear was not repaired? The partial thickness tear is low grade and does not represent a significant structural discontinuity, and therefore it does not mechanically need a structural repair. Do you feel that the impingement syndrome is a result of the June 12, 2012 injury? Impingement syndrome generally develops over time through repetitive use of the shoulder. The June 12, 2012 injury may have initiated and/or exacerbated the symptoms of impingement, but it is unlikely that this injury was the sole cause of the impingement. [25] A medical discussion paper on Shoulder Injury and Disability, revised by orthopedic surgeon Dr. H. Uhthoff in October 2010, was included in the case materials for this appeal. The Tribunal s medical discussion papers are written by independent experts who are recognized in their fields of specialization. They are designed to provide parties and representatives with a general overview of medical topics; it is open to the parties to rely upon a discussion paper, or to distinguish or challenge it with other evidence. Dr. Uhthoff s discussion paper has not been disputed in this appeal. With respect to impingement syndrome, Dr. Uhthoff writes: Impingement Syndrome The Impingement Syndrome is caused by a squeezing of the contents of the space bordered on one side by the coraco-acromial arch and the other side by the humeral head. Both structures are visible on plain x-rays. The contents consist of soft tissues, namely the rotator cuff, in particular the supraspinatus tendon, and the subacromial bursa. The squeezing of these contents in an unyielding space can have two causes:

6 Page: 5 Decision No. 845/15 1. A thickening of the contents, a swelling of the tendon (tendonitis) and/or a swelling of the bursa (bursitis). 2. A decrease of the space, mostly caused by bony outgrowths, such as acromial spurs, osteophytes of the acromio-clavicular joint and/or osteophytes of the humeral head. As a syndrome is defined as a set of symptoms which occur together (Dorland, Medical Dictionary), the pathologic changes leading to the squeezing must be clearly described. As a symptom is the subjective evidence of a disease or of a patient s condition (Dorland, Medical Dictionary), Impingement Syndrome cannot be accepted as a free-standing diagnosis; the cause(s) must be given. The pain caused by the Impingement Syndrome is usually aggravated by internal rotation and flexion (forward elevation) of the glenohumeral joint. It is sometimes argued that impingement may cause a rotator cuff tear through wear and tear. This is an exception. In most instances, the tendon is the site of the original disease, leading to a tear due to the structural weakening of the tendon; the resulting impingement will make the situation worse. In fact, outgrowths of the acromion (bony spurs) form in response to a continued pressure of thickened tendon against the acromial arch. This is important, as the argument often goes that spurs lead to a tendinitis; spurs may aggravate the existing tendinitis. Degenerative processes inside the rotator cuff can be made worse by repeated activities with the hands at shoulder level or above it or by operating vibrating tools. Such activities, when performed repeatedly over a period lasting months and years may also affect the acromioclavicular joint leading to a joint degeneration and the formation of osteophytes. Impingement affects both genders equally. Impingement can start at an early age (around age 20) particularly in athletes. It can develop spontaneously in older people (around 50 to 60 years of age). Is there a relationship between an isolated injury to and recurrent disorders of the shoulder and impingement syndrome? I do not think that an isolated injury can induce an impingement syndrome. However, recurrent episodes and, more so, repetitive work and/or sports activities can cause an impingement (a disorder), usually secondary to wear and tear of the rotator cuff tendons. (v) Discussion and conclusion [26] The question I must answer is whether the worker s June 12, 2012 accident significantly contributed to subacromial impingement, thus establishing a causal link between the accident and the decompression surgery. [27] The worker had no history of right shoulder problems prior to the accident of June 12, He then sustained an injury to his shoulder as a result of a strap catching on a vehicle he was loading on his truck. Following a course of physiotherapy, the worker returned to full duties and had an almost immediate recurrence of symptoms. This led to a diagnosis of impingement syndrome from two specialists, in November 2012 and March [28] The medical opinions on file are each incomplete in some respect. Dr. Rahman highlights claim continuity and the lack of a pre-existing condition, concluding that the worker s condition was consistent with the workplace injury and requires surgery, but does not explain the nature of that condition and the physiological mechanism by which it is linked to the accident history. Dr. Somerville attributes the worker s impingement syndrome solely to the shape of his acromion, but this anatomic variation does not explain the timing of the worker s symptom onset. Moreover, it is unclear why his reporting indicates that there was no shoulder trauma in June 2012, while simultaneously accepting that there was a compensable shoulder strain.

7 Page: 6 Decision No. 845/15 Dr. ElMaraghy states that impingement syndrome develops over time and that the workplace injury was not the sole cause but may have initiated and/or exacerbated the symptoms of impingement, without further explanation. The worker s physiotherapist asserts that the worker s supraspinatus tear led to the impingement, whereas Dr. ElMaraghy suggests the opposite. [29] The Medical Discussion Paper provides some assistance by outlining the causes of impingement, being a thickening of the contents (supraspinatus tendon, bursa) between the coraco-acromial arch and the humeral head, and/or a decrease in the subacromial space due to bony outgrowths. The paper suggests that tendon tear precedes impingement rather than the contrary, and indicates that weakened tendons can lead to impingement. While a single injury is unlikely to induce an impingement syndrome, recurrent episodes and repetitive work might do so. Spontaneous onset is also possible in older people. [30] It is clear that factors other than the workplace accident contributed to the worker s impingement syndrome. Nevertheless, it is sufficient if the accident is a significant contributing factor, rather than the sole factor responsible for the impingement syndrome and associated surgery. [31] On balance, I find the evidence to be in favour of the proposition that the accident of June 12, 2012 was a significant factor in the development of the worker s impingement syndrome. While Dr. Somerville asserts that the shape of the worker s acromion was the cause of the impingement, Dr. Rahman believes that the worker s pre-surgery condition was a result of the workplace injury and Dr. ElMaraghy indicates that the injury may have triggered or aggravated impingement symptoms. There is no evidence of pre-existing symptomology, and the development of the impingement syndrome corresponded with the period following the injury interrupted only by an attempt at full duties. While refuting impingement induced by an isolated injury, the Medical Discussion Paper suggests that the worker s impingement diagnosis is compatible with tendon changes associated with the shoulder injury, the supraspinatus tear, and a premature return to physical duties involving above-shoulder work, as well as the decreased subacromial space due to the congenitally curved acromion and possibly the mild AC joint osteoarthritis. I find, on a balance of probabilities, that the June 12, 2012 accident was a significant factor within this multi-factorial complex. [32] I conclude, therefore, that the worker has entitlement for the decompression surgery undertaken in May 2013, as it constitutes health care which was necessary as a result of the compensable injury.

8 Page: 7 Decision No. 845/15 DISPOSITION [33] The appeal is allowed. The worker has entitlement for the right shoulder arthroscopic decompression surgery of May 2, DATED: June 3, 2015 SIGNED: S. Netten