OASIS, or Open Versus Arthroscopic Stabilization of Shoulder Instability for Subcritical Bone Loss, is a clinical trial that aims to compare three surgical techniques that are commonly utilized for patients that have anterior shoulder instability with subcritical bone loss.
Anterior shoulder instability refers to an injury of the shoulder joint, which is also known as the glenohumeral joint. The glenohumeral joint consists of a centrally located humerus, and is stabilized by ligaments and muscles, along with the joint capsule. However, with anterior shoulder instability, trauma causes the humerus to no longer be located at the center of the joint cavity, and instead subluxes or dislocates in a forward position. This can not only result in pain and joint dysfunction, but can also damage surrounding structures such as nerves, muscles, and blood vessels. Furthermore, traumatic, or recurrent instability may lead to progressive bone loss within the joint. When the amount of bone loss is present, but not greater than a known important amount, this is known as subcritical bone loss. Subcritical bone loss can lead to post-traumatic osteoarthritis if left untreated and predisposes an individual to future episodes of shoulder instability. Subcritical bone loss is considered between 10-20% less than the glenoid width and evidence has indicated that patients may have an increased risk of recurrent stability even with surgical stabilization procedures.
Due to the complicating factor of bone loss, patients presenting with anterior shoulder instability and subcritical bone loss are typically treated with one of three surgical procedures: Arthroscopic Bankart Repair with Remplissage of a Hill-Sachs lesion, Open Bankart Repair, or Latarjet. However, an optimal surgical treatment has yet to be ascertained and currently, no studies have assessed functional recovery comparing these techniques. OASIS aims to evaluate the outcomes of these surgical methods in conjunction with a physical therapy regimen.
Without substantiative evidence indicating which surgical procedure is superior and what factors predict either positive or negative outcomes, a large-scale clinical study is needed to improve the outcomes for these common and devastating injuries.
What does OASIS aim to evaluate?
The overall objective of this clinical trial is to determine the optimal surgical procedure and post-operative rehabilitation strategy and the identification of predictors of success or failure for treatment of military personnel and civilians with acute or recurrent traumatic anterior shoulder instability with subcritical bone loss. To achieve these objectives, we are conducting a randomized, controlled trial comparing arthroscopic Bankart with remplissage/rehabilitation versus open Bankart/rehabilitation versus Latarjet/rehabilitation. The specific aims are:
To determine the effects of Arthroscopic Bankart Repair with Remplissage of a Hill-Sachs lesion versus Open Bankart versus Latarjet on patient-reported outcomes and time to return to duty/activity at pre-injury levels at 6-months, 1- and 2-years. Related to safety, recurrent instability/re-injury will be assessed at 6-months, 1- and 2-years.
To determine if rehabilitation that optimizes range of motion, strength, and functional performance and serial assessments of range of motion, strength, and functional performance predicts successful return to duty/activity, patient-reported outcome scores, and recurrent instability.
The study is enrolling 400 civilian and military participants aged 17 to 50 with acute anterior shoulder instability and subcritical bone loss. Individuals must also meet other inclusion and exclusion criteria as outlined in the Enrollment FAQs. After consenting to the study, participants have an equal chance of being randomized to any of the three surgical techniques, and neither the patient nor the surgeon investigator can choose which technique will be utilized. Post-operatively, participants will undergo a physical therapy regimen for approximately 6 months as part of their standard of care post-operative care. They will also engage in research testing assessments at 3-, 4-, and 6- months. Other research activities over the course of two years include research-based and patient-reported assessments to evaluate the effect of the surgical intervention and rehabilitation program on range of motion, strength, functional performance, and activity levels.
Military personnel are the most at-risk populations for shoulder instability and more than 80% of these individuals have recurrent instability with non-operative treatment. Shoulder instability represents one of the most disproportionately burdensome injuries in the U.S. Military. U.S. Military Service Members, and military trainees in particular, are 20x more likely to have a shoulder instability event than their civilian counterparts.
The results of this study will provide high-level evidence to set standards for improved treatment of anterior shoulder instability with subcritical bone loss in military personnel. In doing so, we will provide prospective, Level 1 evidence for the management of this difficult clinical presentation and improve return to military duty, work, and sports.
There are several civilian and military hospital systems participating in this nationwide multi-site clinical trial, which have experienced orthopedic departments that have participated in several research initiatives. The Study Principal Investigators are Dr. Adam Popchak, PT, PhD, Associate Professor at the University of Pittsburgh and Dr. Jonathan Dickens, MD, Sports Medicine Orthopedic Surgeon at Duke University serves as the Co-Principal Investigator. OASIS is sponsored by the Department of Defense with the University of Pittsburgh at the forefront as the main Coordinating and Data Center Site.