AAOS Names Kappa Delta Ann Doner Vaughn Award Winner for 25-Year Anterior Shoulder Instability Research

The 2025 Kappa Delta Ann Doner Vaughn Award was presented to Matthew T. Provencher, MD, MBA, CAPT MC USNR (Ret.), FAAOS, and his military orthopaedic colleagues for their work in understanding and treating anterior shoulder instability among U.S. military members. Spanning 25 years, this research has had a worldwide impact on treatment options, indications, and surgical techniques, leading to what is now considered by many to be a gold-standard technique for arthroscopic shoulder stabilization. These contributions have guided clinical and surgical decision making while enhancing patient care.

Shoulder instability is one of the most common shoulder injuries, often leading to persistent disability and reduced ability to perform athletic and occupational tasks. It typically occurs when the humeral head partially or completely slips out of the socket due to trauma, overuse, or congenital factors. The team’s research highlighted the heightened prevalence of this condition in military populations, initially identifying a six-fold incidence and an 18-fold increase in anterior shoulder instability at U.S. military academies. The elevated rates among military members are often attributed to this population’s young, active nature, which is often when shoulder instability occurs, coupled with the physical demands and unpredictable nature of the job.

“Once our research team became keenly aware of the high incidence rates among military members who suffered from anterior shoulder instability, we knew we had to take a closer look at identifying why this patient population is so susceptible to this injury and evaluate treatment outcomes for nonoperative and operative care in the short and long term,” said Dr. Provencher, who is a professor of orthopaedics and an orthopaedic surgeon at the Steadman Clinic in Vail, Colorado.

Advancing treatment and improving outcomes
Historically, patients with a first-time dislocation were treated with brief immobilization followed by physical therapy and eventual return to activity. However, after more than two decades of research, the team evolved how first-time shoulder instability is managed in young, active populations by studying military populations. Together, they shifted the treatment philosophy from nonoperative management as a first-line treatment to the “right surgery for the right patients, and to get it right the first time.” This evidence-based approach has improved patient outcomes and has been widely adopted by the international orthopaedic community.

Although there were some previous improvements with arthroscopic Bankart repair over nonoperative management, the team was concerned with the failure rates of this procedure and the consequences it could have for those on active duty.

“Our early attempts at arthroscopic stabilization showed unacceptably high failure rates,” said coauthor COL Brett D. Owens, MD, USN (Ret.), who is chief of sports medicine and professor of orthopaedic surgery at Brown University Alpert Medical School in Providence, Rhode Island. “While we were not the first group to examine the failure rates with this procedure, we were able to examine these results in the highest-risk population in the world, allowing for a robust failure analysis to scrutinize the outcomes.”

With funding from the Department of Defense for a peer-reviewed research grant, the team conducted studies into the early identification of glenohumeral pathomorphology and optimized return-to-duty strategies. To date, they have prospectively enrolled 1,800 patients to evaluate baseline chondral and post-injury chondral changes with baseline and post-injury MRI. Collaborating with the Neer Circle of the American Shoulder and Elbow Surgeons, they also developed consensus guidelines for managing first-time dislocations tailored specifically for military contexts. These guidelines encompass diagnosis, treatment indications, technical factors for surgical success, rehabilitation protocols, and follow-up care.

Addressing bone loss and under-recognized pathology
One of the most significant factors contributing to arthroscopic treatment failures is glenoid bone loss (GBL). Additionally, a humeral bone injury called Hill-Sachs lesion (HSL) magnifies the problem. Those need to be studied together for a complete picture of the instability. The role of GBL in outcomes has been one of the most important topics surrounding the treatment of shoulder instability over the past 20 years.

“Bone loss became one of the seminal topics of this manuscript,” Dr. Provencher said. “Our body of work represents years of research on how best to restore the anatomy and mechanics in the shoulder and make the joint as solid and predictable as possible. We worked closely with musculoskeletal radiologists to identify all underlying pathology, including under-recognized injuries such as humeral avulsion of the glenohumeral ligament (HAGL) tears. We dramatically improved outcomes by optimizing surgical techniques and addressing the full spectrum of pathology—from capsular injuries to bony lesions.”

The team made the following innovations and discoveries from military centers all over the world:

• establishing a glenoid and humeral head bone loss model to predict outcomes in patients indicated for arthroscopic Bankart repair using age, sex, duration of shoulder instability, symptoms, and radiographic images of the anatomy of the lesions
• defining the amount of bone loss to determine the type of surgery patients receive
• improving outcomes by restoring the anatomy of the shoulder with a novel osteochondral allograft solution for glenoid bone loss called the distal tibia allograft, thereby providing biomechanical superiority and improved joint congruity

“The distal tibia proved to be an exceptional match, offering dense, robust bone with good cartilage,” Dr. Provencher added. “Thanks to the incredible gift of life, we developed a bone and cartilage solution that demonstrated good outcomes in healing, bone incorporation, and joint stability. This discovery allowed us to try to restore the shoulder’s anatomy and mechanics and repair the injured bone, capsule, and labrum to create a joint that is as stable and reliable as possible.”

The research also catalyzed the Military Orthopaedic Tracking Injuries Outcomes Network (MOTION), an initiative established in 2016, developed in collaboration with military colleagues, and spearheaded by COL Jonathan F. Dickens, MD, MC, USAR, FAAOS. Now the world’s largest military outcomes database, MOTION has more than 10,000 patients enrolled and is pivotal in tracking long-term outcomes of instability-related injuries. The database, which helped inform many of the team’s discoveries, aims to use data to enhance military medical readiness and optimize the use of medical resources through comprehensive evaluations of short- and long-term musculoskeletal injury outcomes.

“It’s difficult for the civilian world to understand the profound sense of responsibility felt by military surgeons, particularly those who have served in wartime,” said COL John M. Tokish, MD, MC, USAR, FAAOS, coauthor and professor of orthopaedic surgery at Mayo Clinic, Phoenix, Arizona. “There is a tremendous and palpable sense of legacy, paid for by those who came before us, that we are committed to honoring and passing on to future generations. Through the dedication of pioneers who translated this mission into impactful research and with the military’s support, we’ve made significant strides. Our team has advanced the understanding of anterior shoulder instability, from nuanced injury patterns to long-term epidemiology and randomized, controlled trials, culminating in over 270 peer-reviewed publications that have transformed patient care worldwide. This work is a testament to the collective effort to give back to the military and improve outcomes for all.”

In addition to Drs. Owens, Tokish, and Dickens, the following coauthors contributed to the research: Eoghan T. Hurley, MD, PhD; CAPT Lance E. LeClere, MD, USNR; LTC Andrew J. Sheean, MD, USAF; COL Jeanne C. Patzkowski, MD, USA; CAPT Robert A. Waltz, MD, USN; and LTC Stephen Parada, MD, USA.

“I am incredibly humbled and deeply grateful for receiving the Kappa Delta Award—not only to the exceptional team behind this research but also to the countless individuals in the military, my mentors, and many others who have helped pave the way for studying this critical condition that we encounter so often in military settings,” Dr. Provencher said. “It is an extraordinary honor to receive this recognition, especially as an all-military group, marking a significant milestone for teams like ours.”

Jennifer Lefkowitz is a freelance writer for AAOS Now.

For a list of disclosures, funding, and conflicts of interest, email media@aaos.org.

Reference

1. Owens BD, Duffey ML, Nelson BJ, et al. The incidence and characteristics of shoulder instability at the United States Military Academy. Am J Sports Med 2007;35(7):1168-73.