TSA Techniques in Glenohumeral OA

Comparison of Shoulder Arthroplasty Techniques in the Treatment of Glenohumeral Osteoarthritis: Protocol

Osteoarthritis (OA) of the shoulder is a disease resulting from the wearing down of cartilage over time. OA can produce pain and dysfunction at the affected joint and is a growing occurrence in an aging population. Total shoulder arthroplasty (TSA) is a surgical treatment used to treat patients with shoulder OA which involves replacing the worn-out ball and socket shoulder joint with prosthetic components. TSA is performed today with high success rates, however, complication rates associated with TSA remain prevalent particularly when the arthritis is associated with bone erosion on the glenoid (socket). Given the high rate of revisions associated with TSA treatment in the setting of glenoid bone erosion, a number of surgical strategies have been developed. These surgical techniques include eccentric reaming which involves removing bone from the front of the socket, augmented glenoid component implantation, and posterior bone grafting to compensate for glenoid bone loss, and reverse shoulder arthroplasty. Few research studies have compared these different surgical techniques to one another. Previous studies have been limited to case series with small sample sizes and respective designs. This study is being conducted to determine which approach produces better outcomes. For the purpose of this study we will be comparing total shoulder arthroplasty techniques a) augmented glenoid component and eccentric reaming and b) augmented glenoid component and bone grafting in participants with advanced glenohumeral osteoarthritis.

Patients who have 10-15 degrees of retroversion will be randomly assigned to one of two standard of care treatment groups: TSA with eccentric glenoid reaming or TSA with augmented glenoid component implantation. Patients whose condition involves > 15 degrees of retroversion will be randomly assigned to one of two standard of care treatment groups: TSA with augmented glenoid component implantation or posterior glenoid bone grafting. The primary objective will be measured by the Western Ontario Osteoarthritis of the Shoulder Index (WOOS) score pre-operatively and at post-operative time intervals (i.e. 3, 6, 12 and 24 months). Secondary Objectives: i) To 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 between study arms in both age groups. ii) To determine the difference in disease specific quality of life between treatment allocations in both age groups as measured by the Constant score, the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment form (ASES) and the EuroQol Group EQ-5D-5L score pre-operatively and at post-operative time intervals (i.e. 3, 6, 12 and 24 months), as well as adverse events, and health care utilization.

Pre-operative CT imaging and surgical planning software based on pre-operative CT scans will be used in each case to determine the degree of eccentric ("high side") anterior reaming to within < 10 degrees of neutral glenoid version.

Patients will undergo standard glenoid preparation and implantation of a posteriorly augmented glenoid component. The degree of posterior augment will be based on pre-operative CT scan assessment and templating software with the goal of correcting glenoid retroversion to within 10 degrees of neutral version.

Patient will undergo a total shoulder arthroplasty as per standard technique. Glenoid version will be restored to within 10 degrees of neutral with a posterior glenoid bone graft. The bone graft will be harvested from the humeral head and fixed to the posterior glenoid with mini-fragment screws.

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.

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.

The EuroQol 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. 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).

The EuroQol 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. 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).

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).

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.

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.

Patient Population The target population is both men and women of any age with advanced osteoarthritis of the glenohumeral joint who are considered by the treating surgeon to be a candidate for shoulder replacement. The type of arthritic process will not be considered a deciding factor. The arthritis must be amenable to treatment using either a humeral head replacement (stemmed or stem-less), or a standard total shoulder replacement. Inclusion Criteria Patients who have failed standard non-surgical management of their shoulder osteoarthritis 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 6 months. Medical management will be defined as: The use of drugs including analgesics and non-steroidal anti-inflammatory drugs Physiotherapy consisting of stretching, strengthening and local modalities (ultrasound, cryotherapy, etc.) Activity modification Patients will present with a glenoid retroversion between 10-26 degrees. Imaging, and intra-operative findings confirming advanced humeral head cartilage loss, with or without glenoid cartilage loss. Age 18 years or older Exclusion Criteria < 10 degrees / > 27 degrees of glenoid retroversion 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