Electronic Thesis and Dissertation Repository

Thesis Format

Integrated Article


Doctor of Philosophy


Health and Rehabilitation Sciences

Collaborative Specialization

Musculoskeletal Health Research


MacDermid, Joy C


Injury or degeneration of rotator cuff tendon leads to rotator cuff disease (subacromial impingement syndrome and rotator cuff tears). Shoulder pain – pain in the upper arm close to the deltoid muscle insertion has been reported as the most common symptom for subacromial impingement syndrome and rotator cuff tears. However, the current state of evidence on treatment effectiveness of rotator cuff disease is indeterminate. The shoulder function is essential for many of the physically demanding tasks that firefighters perform on the fire ground. For fire services and firefighters, the preservation of active duty is critical for their continued service to their communities. However, the prevalence of shoulder pain among Canadian firefighters has not been synthesized. Further, high quality randomized clinical trials (RCTs) provide the highest level of evidence and assist in clinical decision making. The International Committee of Medical Journal Editors (ICMJE) recommendation of RCT trial registration in public trials registry has been made to improve the reporting, transparency, rigor and reproducibility in RCTs. However, there is a paucity of evidence on the proportion of RCTs with proper trial registrations in the field of rehabilitation therapy. Therefore, the purposes of this thesis were 1) to assess the effects of arthroscopic versus mini-open rotator cuff repair surgery on function, pain and range of motion at in patients with rotator cuff tears; 2) to quantify the effects of surgical vs conservative interventions on clinical outcomes of pain and function in patients with subacromial impingement syndrome; 3) to assess the prevalence of musculoskeletal disorders (MSDs) among Canadian firefighters, 4) to examine the proportion of RCTs that were reported to have been prospectively, retrospectively registered or not registered in the field of rehabilitation therapy, and 5) to use the synthesized evidence to inform the design of a single center (fire-station), investigator-blinded, randomized, 12-month, parallel-group, superiority trial for the evaluation of the efficacy of a shoulder exercises on clinical outcomes in firefighters with shoulder pain.

From the existing literature, we found evidence that both arthroscopic and mini-open techniques to rotator cuff repairs with post-operative rehabilitation exercises were effective in improving clinical outcomes of function, pain and shoulder range of motion in patients with rotator cuff tears. However, the between-group differences in outcomes were too small to be clinically important. The effects of surgery plus physiotherapy (exercises) vs physiotherapy (exercises) alone on pain and function were too small to be clinically important at 3-, 6-months, 1-, 2-, 5- and ≥ 10-years follow up. This further highlighted that rehabilitation exercises be considered as the first treatment approach in patients with shoulder pain. We also identified high point-prevalence estimates (1 in 4 firefighters) of shoulder-, back-, and knee-related MSDs among Canadian firefighters (shoulder pain was 23%). Our review study indicated that fifteen years after the introduction of standards for RCT registration by ICMJE, only one-third of the RCTs in the field of rehabilitation therapy were prospectively registered. Subsequently, the emergence of further evidence (observational studies in firefighters and RCTs in active-duty military personnel) indicating the clinical effectiveness of occupation-specific rehabilitation exercises along with our evidence syntheses provided the rationale for the design and conduct of an RCT to assess the effectiveness of firefighter-specific rehabilitation exercises among Canadian firefighter with shoulder pain.

Summary for Lay Audience

Inside the shoulder joint there is a small band which is called a tendon. This tendon in your shoulder allows your arm to move and do many things such as eating, brushing your teeth, combing your hair and dressing up. Pain in the shoulder is a very common problem that affects many people. This pain may be due to a tear (cut) in the shoulder tendon or the tendon could have become very sensitive (inflamed). It is not clear what type of surgery (arthroscopic or mini-open) is helpful for patients with a cut in their shoulder tendon. Also, for patients with inflamed (sensitive) tendon, it is not clear if surgery plus shoulder exercises or just shoulder exercises alone, is the best treatment option. This pain in shoulder is also very common in firefighters. We also don’t know what percentage of research details published in physiotherapy was originally made available to the public before the start of the research itself. This is a very important step for researchers to do (make research details available to everyone before starting research) because only by making research details available to public can the researchers stay transparent with the public and other researchers. So, we reviewed many studies and found that both types of surgery (arthroscopic or mini-open) are helpful for patients with a cut in their shoulder tendons. Also, we found that there is no difference in improving shoulder pain when going for surgery and doing shoulder exercises vs only doing shoulder exercises alone for patients with inflamed (sensitive) tendon. Our research also showed that shoulder pain is very common in Canadian firefighters (1 in 4 firefighters have shoulder pain). Plus, only about 33% of research details published in physiotherapy were made available to the public and other researchers before the start of the research itself (this is very important for transparency reasons). So, we used all these results from our work and carefully designed a study with special exercises for firefighters to do to improve their shoulder pain.