As the number of orthopaedic surgeries in the United States hits an all-time high, researchers are looking for novel ways to track patients’ progress and identify pre-surgery those at risk for poorer outcomes. In Nashville, Vanderbilt Sports Medicine is leading a national research effort to measure both short- and long-term outcomes of knee and shoulder surgeries.
Vanderbilt’s MOON Study
In 2001, the Multicenter Orthopaedic Outcomes Network was established to examine how patients fare following anterior cruciate ligament reconstruction. Founded by former Vanderbilt professor Kurt Spindler, MD, this NIH-funded consortium consists of 13 sports medicine physicians across seven sites and relies heavily on the work of Vanderbilt’s biostatistics and epidemiologists, research coordinators and assistants. Goals of the study were to identify both the short and long-term prognoses and predictors of sports function, activity level and general health through validated patient-reported outcomes; to identify symptoms and signs of osteoarthritis; and to quantify the incidence of ACL reconstruction graft and/or contralateral ACL failures and additional surgical procedures.
Since 2002, MOON has attained over 85 percent follow-up at both two and six years post-surgery from more than 3,500 enrolled patients.
Results
MOON’s results have already changed the way ACL surgeries are performed in certain populations including high school, college and competitive athletes in their primary ACL reconstructions. That’s because first-time surgery failure was often predicted by age and graft choice – autograft was more effective among younger patients than allograft. An unanticipated positive result was the stable outcomes seen at six years, as compared to two years. The six-year follow-up also found revision ACLR and allograft are universal to both sports outcomes and activity level. Smoking, higher BMI, and older age also were predictors for some outcomes, while gender was not a predictor of sports outcomes.
MOON continues to enroll and follow patients with the goal of identifying predictors of who does and does not do well after surgery.
MOON Shoulder Group
In 2004, VUMC recruited John E. Kuhn, MD, MS, as chief of shoulder surgery for Vanderbilt Sports Medicine. Under Kuhn’s direction, the MOON Shoulder Group was established to study disorders of the shoulder using a multicenter collaboration. Kuhn’s shoulder study looked at the nonoperative treatment of full thickness rotator cuff tears in order to help understand indications for surgery. A decade later, MOON Shoulder now includes 23 surgeons at 12 sites across the U.S., with each site examining a different disorder.
Objectives of the MOON Shoulder Group’s research are to lend insight into the natural history of rotator cuff disease; identify patients at risk for progression of rotator cuff disease; and to assist physicians in the management of patients with shoulder injuries.
“In our first study, our research group could not come to a consensus on how best to treat patients with shoulder pain who had rotator cuff tears without a history of an injury,” said Kuhn. “We knew there was a lot of geographic variation in surgery rates. We also knew that surgeons did not agree on who needed surgery and who didn’t.”
The decision was made to conduct a study where all patients with symptomatic atraumatic full thickness rotator cuff tears would be sent through a standard, evidence-based physical therapy program. Patients were offered surgery if at any time they did not do well. The group identified several interesting findings:
Physical therapy was effective in preventing surgery in over 80 percent of patients.
Effects of the physical therapy program lasted at least two years.
The patient’s expectations with regard to treatment drove the decision to have surgery: If a patient believed therapy would work, it would. If the patient did not believe therapy would work, it did not.
Severity of the rotator cuff disease had very little to do with the patient’s symptoms. It did not correlate with patient pain, duration of symptoms, activity level, or the decision to have surgery.
“This work is important, as many patients are told they need to have surgery with atraumatic full thickness rotator cuff tears, but this does not seem to be the case,” Kuhn said. “We know there are over 5 million Americans with rotator cuff tears, yet fewer than 5 percent come to surgery. We also know that if the rotator cuff repair fails, patients still feel better suggesting the tear was not the source of pain. Our study demonstrated that the therapy program was effective, even if done at home for the majority of the time. This has important implications with regard to healthcare costs.”
MARS Undertakes Knee Revisions
In 2006, a third study was launched to examine outcomes of Multicenter ACL Revision Surgery (MARS) at two, six and 10 years post-surgery. More than 1,200 participants have enrolled in MARS to date. According to Kuhn, the infrequency of revision surgery constituted the need for a multicenter approach. There are 87 surgeons from more than 53 sites in North America contributing to the body of knowledge.
While MARS is under the leadership of Rick Wright, MD, at Washington University in St. Louis, Kuhn said a large number of Vanderbilt resources and faculty assist in the ongoing study.
In addition to the MARS work, Kuhn said, “Literally dozens of research personnel at Vanderbilt play a role in conducting the studies these groups perform, making Vanderbilt the ‘hub’ for the MOON ACL and MOON Rotator Cuff Studies.”