TSA v RSA in Osteoarthritic Shoulders With Greater Than 15 Degrees of Retroversion (SERVASA15)

Study Evaluating Reverse Versus Anatomic Total Shoulder Arthroplasty in Shoulders With Greater Than 15 Degrees of Retroversion in the Treatment of Osteoarthritis: Protocol

This study will compare total shoulder arthroplasty (TSA) with an augmented glenoid component and reverse shoulder arthroplasty (RSA) procedures, in participants with advanced glenohumeral osteoarthritis aged 65 years and older, who also present with greater than 15 degrees of glenoid retroversion, in the context of a prospective, randomized controlled trial to determine the optimal treatment in this patient population.

Osteoarthritis (OA) of the shoulder or glenohumeral joint, is a disease resulting from the wearing down of cartilage over time. OA can be the cause of pain and dysfunction and is a growing occurrence in our aging population. Total shoulder arthroplasty (TSA) or Reverse shoulder arthroplasty (RSA) are common surgical procedures used to treat patients with glenohumeral OA. TSA involves replacing the worn-out ball and socket glenohumeral joint with prosthetic components. TSA is performed today with high success rates, however, complication rates associated with TSA remain prevalent, particularly when the OA is associated with bone erosion on the glenoid (socket). An additional surgical technique using an "augmented glenoid component" has been developed to address this issue of missing bone. This technique attempts to realign and restore balance to the shoulder joint using artificial components and is also being performed as standard of care. RSA is an alternative surgical procedure involves replacing and reversing the ball and the socket (i.e. opposite of TSA). RSA is typically performed in patients with a rotator cuff deficiency and more severe OA. Though RSA procedures show marked increase in clinical and functional outcomes, evidence of its long-term results are sparse, and as such is typically reserved for when treating an older patient population. Few research studies have compared these different surgical techniques in older population and those with a more advanced level of OA degeneration. Previous studies have been limited to case series with small sample sizes and respective designs. This research will provide surgeons with new information regarding the best treatment for this patient population. This randomized controlled trial (RCT) will compare TSA + augmented glenoid component and RSA procedures to determine which approach produces better functional outcomes and quality of life in those with advanced OA who are in older patient population (65 years and older). Primary Objective: Determine the difference in disease specific quality of life between patients diagnosed with glenohumeral OA who present with greater than 15 degrees (-15.1, -17, -20…etc.) of glenoid retroversion and undergo either a TSA + augmented glenoid component or RSA as measured by the WOOS score at 24-months and 5-years post-operative. Secondary Objectives: i) Determine the difference in disease specific quality of life between patients diagnosed with glenohumeral OA who present with greater than 15 degrees of glenoid retroversion, and undergo a either a TSA + augmented glenoid component or RSA as measured by the Constant score, the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment form (ASES), EuroQol Group EQ-5D-5L, pain Visual Analog Scale (VAS), and Subjective Shoulder Value (SSV) scores at 24-months and 5-years post-operative, as well as adverse events, and health care utilization. ii) Determine the survivorship of the components as measured by the degree of radiographic lucencies and component alignment determined by a CT scan at 1- and 5-years post-surgery. Clinical Relevance: Glenohumeral OA results in pain and dysfunction, which negatively impacts quality of life. As such, determination of superior treatment approach will lead to significant improvement in quality of life, and cost savings through avoidance of recurrence and/or reoperation, as well as decreased morbidity for patients in this population.

TSA procedure involves replacing the worn-out ball and socket joint with prosthetic components. An additional surgical technique, "augmented glenoid component" implantation is performed when there is missing bone in the shoulder and is currently being done as standard of care. This technique is used particularly when a large amount of instability within the shoulder joint is present. This technique attempts to realign and restore balance to the shoulder joint using artificial components.

RSA procedure is similar to a TSA, however the orientation of the ball and socket joint is placed in the reverse position

Replacement of the shoulder joint (ball and socket, or humeral head and glenoid) using prosthetic components. A prosthetic component is also implanted to correct for the amount of bone loss in the shoulder and restore stability.

Replacement of the shoulder joint like the TSA, however the orientation of the ball and socket is reversed.

The Western Ontario Osteoarthritis of the Shoulder Index (WOOS) is a disease specific evaluation, proven to be an accurate and valid assessment of function after shoulder replacement. The WOOS is a patient-reported measure, 19-question survey. Each question is measured using a visual analog scale rated from 0-100, where higher scores mean better outcome.

The Western Ontario Osteoarthritis of the Shoulder Index (WOOS) is a disease specific evaluation, proven to be an accurate and valid assessment of function after shoulder replacement. The WOOS is a patient-reported measure, 19-question survey. Each question is measured using a visual analog scale rated from 0-100, where higher scores mean better outcome.

Radiological parameters will be examined using Computed Tomography (CT). These scans will be analyzed for abnormalities in component alignment, and evidence of lucencies or loosening. Higher incidence of loosening, or noted abnormalities will be compared between groups. A higher incidence indicates worse outcomes.

Radiological parameters will be examined using Computed Tomography (CT). These scans will be analyzed for abnormalities in component alignment, and evidence of lucencies or loosening. Higher incidence of loosening, or noted abnormalities will be compared between groups. A higher incidence indicates worse outcomes.

The ASES is a shoulder specific assessment divided into two sections: pain and activities of daily living (ADL). Pain is recorded on a visual analogue scale (0-10), lower scores indicate better outcomes. There are 10 activities of daily living questions, each are recorded on a 4 level likert scale (0-3), which a higher score indicates a better outcome. The overall score is an equal weight of the two sections and produces a score out of 100. The higher the score, the better the outcome.

The ASES is a shoulder specific assessment divided into two sections: pain and activities of daily living (ADL). Pain is recorded on a visual analogue scale (0-10), lower scores indicate better outcomes. There are 10 activities of daily living questions, each are recorded on a 4 level likert scale (0-3), which a higher score indicates a better outcome. The overall score is an equal weight of the two sections and produces a score out of 100. The higher the score, the better the outcome.

Subjective pain value of the shoulder will be assessed using a questionnaire. Pain is recorded on a visual analogue scale (0-10), lower scores indicate better outcomes. The higher the score, the worse the outcome.

Subjective pain value of the shoulder will be assessed using a questionnaire. Pain is recorded on a visual analogue scale (0-10), lower scores indicate better outcomes. The higher the score, the worse the outcome.

A participant's subjective value on shoulder function will be assessed using a questionnaire. The overall functional value of the shoulder is written as a percentage from 0-100% of a normal shoulder. The higher the score, the better the outcome.

A participant's subjective value on shoulder function will be assessed using a questionnaire. The overall functional value of the shoulder is written as a percentage from 0-100% of a normal shoulder. The higher the score, the better the outcome.

The EQ-5D-5L quality of life questionnaire is a brief, easy to administer generic health status questionnaire, consisting of five dimensions (mobility, self-care, usual activities, pain/discomfort, anxiety/depression) each of which can take one of five responses (each question rated 1-5), lower scores indicate better outcome. It also includes a visual analogue scale for recording an individual's rating of their current health-related quality of life (scale 0 to 100), where a higher score indicates a better outcome.

The EQ-5D-5L quality of life questionnaire is a brief, easy to administer generic health status questionnaire, consisting of five dimensions (mobility, self-care, usual activities, pain/discomfort, anxiety/depression) each of which can take one of five responses (each question rated 1-5), lower scores indicate better outcome. It also includes a visual analogue scale for recording an individual's rating of their current health-related quality of life (scale 0 to 100), where a higher score indicates a better outcome.

The Constant Score reflects an overall clinical functional assessment. This instrument is based on a 100-point scoring system. Subjective findings (pain, activities of daily living, and working in different positions) make up a total of 35 points. Objective measurements make up the remaining 65 points.The test is divided into four sub-categories: (1) pain is measured using 4 likert levels (15 points maximum), where a higher score indicates a better outcome; activities of daily living are measured using a likert scale, where a higher number indicates better outcomes (20 points maximum); mobility is measured by an assessor, and rated using a likert scale where a higher score indicates better outcomes (40 points maximum); finally, strength is measured by an assessor where 1 point is given per 0.5kg of force (maximum 25 points), a higher score indicates better outcomes. All categories are added together, and a total score out of 100 is given (higher score indicates better outcome).

The Constant Score reflects an overall clinical functional assessment. This instrument is based on a 100-point scoring system. Subjective findings (pain, activities of daily living, and working in different positions) make up a total of 35 points. Objective measurements make up the remaining 65 points.The test is divided into four sub-categories: (1) pain is measured using 4 likert levels (15 points maximum), where a higher score indicates a better outcome; activities of daily living are measured using a likert scale, where a higher number indicates better outcomes (20 points maximum); mobility is measured by an assessor, and rated using a likert scale where a higher score indicates better outcomes (40 points maximum); finally, strength is measured by an assessor where 1 point is given per 0.5kg of force (maximum 25 points), a higher score indicates better outcomes. All categories are added together, and a total score out of 100 is given (higher score indicates better outcome).

Rates of study adverse events or serious adverse events (e.g. number of reoperations) will be monitored and recorded and compared between study groups. A higher rate of adverse events indicates a worse outcome.

Health care utilization will be monitored and recorded using a questionnaire. These questions will include healthcare the patient accessed, cost of care, and medications taken during treatment. From this information, a cost-effectiveness analysis will be completed, which will adhere to the best practices for conducting and reporting of health economic evaluations.

Inclusion Criteria: Diagnosis of idiopathic shoulder OA. Patients who have failed standard non-surgical management of their shoulder OA who would benefit from a shoulder arthroplasty. Failed medical management will be defined as persistent pain and disability despite adequate standard non-operative management for at least 6 months. Medical management will be defined as: a) The use of drugs including analgesics and nonsteroidal anti-inflammatory drugs, b) Physiotherapy consisting of stretching, strengthening and local modalities (ultrasound, cryotherapy, etc.), c) Activity modification Imaging, and intra-operative findings confirming advanced glenohumeral cartilage loss Patients with a glenoid deficiency and >15 degrees of glenoid retroversion up to a maximum of 26 degrees of glenoid retroversion (i.e. -15.1, -17, -20…etc.) 65 years of age and older Exclusion Criteria: Active joint or systemic infection Rotator cuff arthropathy Significant muscle paralysis Charcot's arthropathy Major medical illness (life expectancy less than 1 year or unacceptably high operative risk) Unable to understand the consent form/process Pregnancy Psychiatric illness that precludes informed consent Unwilling to be followed for the duration of the study Retroversion cannot be surgically corrected to within 10 degrees of neutral History of previous shoulder surgery on affected side Rheumatoid arthritis in the affected shoulder

Individual participant data will not be shared with other researchers unless requested and an agreement is in place. Only aggregate data will be made public (study results).