Published 11/1/2013
Mary Ann Porucznik; Washington Health Policy Fellows

Study Takes Close Look at Impact of ACL Surgery

Focus on economics indicates surgery may be “a good deal”

In the second of a series of studies examining the economic impact of orthopaedic procedures, researchers found that outcomes for patients who had appropriately selected anterior cruciate ligament (ACL) reconstruction were both more effective (short- to intermediate-term) and less costly than rehabilitation alone. In addition, long-term costs to society were approximately $50,000 less per patient undergoing ACL reconstruction compared to rehabilitation.

“In younger patients, surgery for an ACL tear is usually the best option for getting them back on their feet and reducing the likelihood of arthritis down the road,” said Mininder S. Kocher, MD, MPH, associate director, division of sports medicine at Boston Children’s Hospital and one of the study’s authors. “Patients and their families are often worried about their ability to return to sports, their mobility in the future, and the cost of the surgery. This study sheds light on all three of these important factors.”

How to treat a torn ACL is a matter of considerable controversy. Nonsurgical treatment—such as bracing, physical therapy, and activity modification—can be a successful option for some patients, especially those who have partial tears or are less active. But more than 200,000 ACL injuries occur annually, many in people who participate in sports that require cutting and pivoting, such as basketball, football, skiing, and soccer.

About 1 of every 100 female high-school athletes in these sports—as well as handball and tennis—will injure an ACL before she graduates, according to Letha Y. Griffin, MD, a sports medicine specialist at Peachtree Orthopaedic Clinic in Atlanta. In college-level players, notes Dr. Griffin, the risk rises to 1 in 10—and is much higher than the rate among male athletes. Also, studies have shown that if an athlete tears the ACL in one knee, the likelihood of sustaining an injury in the opposite knee increases.

In addition, about half of all ACL injuries also involve damage to the meniscus, articular cartilage, and other ligaments, or bone bruises beneath the cartilage surface. This can lead to early-onset osteoarthritis of the knee. Studies indicate that the risk of knee osteoarthritis developing within 10 years after injury in patients who have a torn ACL but no meniscal tear is relatively low (less than 15 percent). However, that risk doubles—or even triples—if the patient has both a torn ACL and a torn meniscus.

Surgery or rehabilitation?
The new study, “Societal and Economic Impact of Anterior Cruciate Ligament Tears,” was based on data from two prospective studies: the Multicenter Orthopaedic Outcomes Network (MOON) database and the knee ACL, nonsurgical versus surgical treatment (KANON) study. The databases included more than 1,000 patients, and the treatment model examined both surgical reconstruction and nonsurgical rehabilitation.

The data were used to populate a Markov decision model (a mathematical model of ACL tears), which was used to estimate the total societal savings associated with ACL reconstruction. The model compared direct medical care costs as well as indirect costs (such as lost wages from work and disability payments) for both surgical and nonsurgical treatments.

According to lead author Richard C. Mather III, MD, “Both ACL reconstruction and rehabilitation treatment strategies are likely to yield high-quality, low-cost care when performed for the appropriate patient. In the short-to-intermediate term, opportunities for improving treatment for ACL tears reside in better understanding patient preferences and in patient-centered care. For example, a patient who is at risk of diminished quality of life due to an unstable knee might be better treated with early ACL reconstruction, whereas a low-demand patient who has a lower-than-average risk of symptomatic instability could undergo rehabilitation as an initial treatment.”

The study examined the impact of surgery or rehabilitation in two time frames: short-to-intermediate (up to 6 years), and long-term (lifetime) (Fig. 1). This approach provided Level I evidence for results in the short-to-intermediate time frame—information that could help to direct immediate treatment decisions. Long-term estimates underscored the high costs of ACL injuries, regardless of the type of treatment.

Treatment effectiveness was expressed as quality-adjusted life years (QALYs), and costs were estimated in 2012 dollars. To reflect all payer costs, estimates of direct medical costs were adjusted by using payment rates of insurers other than Medicare (as a percentage of the Medicare rate), weighted by the national distribution of payers.

Costs and outcomes
In both time frames, ACL reconstruction resulted not only in lower total costs (direct and indirect), but also in higher QALYs than rehabilitation (
Table 1).

Findings indicate that the average lifetime societal benefit of reconstruction surgery is approximately $50,000 per patient; most of the societal savings are realized based on the patient’s ability to return to a more functional, pain-free lifestyle. The mean lifetime cost to society for a typical patient undergoing ACL reconstruction was $38,121 compared with $88,538 for rehabilitation. On this basis, lifetime societal savings from ACL surgeries in the United States alone would total about $10.1 billion annually. The long-term perspective demonstrates the tremendous societal economic impact of ACL tears; the cost to society ranges from $8 billion to $18 billion annually.

“This study also suggests that we might want to rethink the use of ‘conservative’ to describe nonsurgical treatments,” said Dr. Mather. “When a patient cohort simulation was performed, rehabilitation alone resulted in greater variation in cost and quality of life than ACL reconstruction. In other words, ACL reconstruction provides a more predictable, consistent outcome.”

When the ACL injury involves meniscal damage, reconstruction can help minimize any further damage to the knee that can result in the development of knee osteoarthritis. Because ongoing instability can lead to future meniscus and cartilage injuries not sustained in the original injury, ACL reconstruction may also help avoid additional surgeries.

The benefit of ACL reconstruction has long been known by patients who have returned to their active lifestyle following the surgery. However, this study is “the first to examine the comprehensive economic impact of joint preservation,” said Dr. Mather. “Many people think that ACL tears are due to an active lifestyle or sports injury. This analysis shows that joint preservation treatment has a powerful economic impact.”

“We know ACL patients who need this surgery generally benefit from it because the knee is more stable,” said AAOS Past President John R. Tongue, MD. “But until now, the economic value of ACL reconstruction surgery has been hard to quantify. Considering the fact that many ACL patients are young and eager to get back to their active lives, this study provides a key perspective for evaluating surgery versus rehabilitation.”

According to the researchers, if all ACL injuries were treated surgically, approximately 59 percent of patients would eventually show radiographic signs of osteoarthritis of the knee. Of these patients, about one in five (25,800) would need a total knee arthroplasty. In comparison, if only rehabilitation was used, 70 percent of patients would eventually show signs of osteoarthritis and 30,800 would need a total knee arthroplasty.

“This is the first study to demonstrate the importance of a societal perspective when considering the costs and benefits of ACL repair and policies that will affect access to this procedure,” said study coauthor and healthcare economist Lane Koenig, PhD. “This study provides a foundation for assessing the societal benefits of procedures and health services that will add to the conversation people are having about improved, cost-conscious health care.”

Coauthors of “Societal and Economic Impact of Anterior Cruciate Ligament Tears,” include Drs. Mather, Koenig, and Kocher; Timothy M. Dall, MS; Paul Gallo, BS; Daniel J. Scott, MA; Bernard R. Bach Jr, MD; the MOON Knee Group; and Kurt P. Spindler, MD.

Disclosures: This study was funded by the AAOS. MOON, which provided the clinical outcomes data, was supported by the National Institutes of Health, Smith & Nephew, and DonJoy Orthopaedics. Dr. Mather—Stryker, KNG Health Consulting, for[MD]; Dr. Koenig—BTG International, Johnson & Johnson; Dr. Kocher—Best Doctors, Biomet, Gerson Lehrman Group, OrthoPediatrics, Smith & Nephew, Fixes 4 Kids, Pivot Medical, Saunders/Mosby-Elsevier, AAOS, ACL Study Group, American Orthopaedic Society for Sports Medicine (AOSSM), Harvard Medical School, Harvard School of Public Health, Pediatric Orthopaedic Society of North America, PRISM, Steadman Philippon Research Institute; Dr. Bach—Arthrex Inc., CONMED, Linvatec, DJ Orthopaedics, Ossur, Smith & Nephew, Tornier, SLACK Incorporated, Orthopedics Today, AOSSM; Dr. Spindler—DJ Orthopaedics, Smith & Nephew, Arthritis Foundation, National Football League Medical Charities, Orthopaedic Research Society; Messrs. Dall, Gallo, and Scott—no information available

Mary Ann Porucznik is managing editor of AAOS Now. The list of AAOS Washington Health Policy Fellows can be found on the AAOS website at www.aaos.org/dc

Bottom Line

  • Anterior cruciate ligament (ACL) tears can be successfully treated either surgically or nonsurgically; treatment decisions should be made based on the extent of the injury, any associated injuries, and patient activity levels and goals.
  • The direct medical costs of surgical treatment of ACL injuries are more than offset by cost savings from increased function and productivity.
  • Nonsurgical treatment can be a successful option for patients who have only partial tears or are less active.

Additional Information
Societal and Economic Impact of Anterior Cruciate Ligament Tears