11:04 AM

What Everyone Should Know About ACL Surgery

Choosing the right treatment option for an ACL tear upfront can have lifelong implications. On behalf of Hospital for Special Surgery, the world’s largest academic medical center specializing in musculoskeletal health, we the surgeons of the HSS Sports Medicine Institute have drafted the following guidelines for people who are considering ACL treatment.

Reconstruction is the current standard of care surgical treatment for tears of the anterior cruciate ligament (ACL). This procedure typically uses a graft, or a piece of tissue, placed in the knee minimally invasively, using small incisions. About 300,000 ACL reconstructions are performed annually in the United States with well documented rates of success.

ACL repair is an older technique that involved suturing (sewing) torn ACL tissue, not rebuilding it with a graft. ACL repair was performed in the 1970s at select institutions, including Hospital for Special Surgery, but was abandoned due to unacceptably high failure rates of up to 50%.

Today, ACL repair has been modernized and can be performed through a minimally invasive approach. Proponents suggest that modern ACL repair techniques may be performed safely and may lead to a quicker recovery than ACL reconstruction. However, the limited studies to date raise questions that must be discussed in detail with your surgeon.

1. It is critically important to get ACL surgery right the first time.

When ACL surgery fails, surgeons must do a revision procedure to correct or revise the problems that were not fully addressed the first time. Revision requires reconstructive ACL surgery with a graft. (ACL repairs cannot be done as revisions.) Redoing ACL surgery may result in higher rates of failure, lower rates of return to sports, and increased risk of osteoarthritis.

The importance of successful initial ACL surgery holds true for people of all ages, but it is particularly critical for young athletes, for whom a failed surgery can have devastating consequences, including years lost from sport in the short term as well as chronic pain and loss of function in the long term.

2. Failure rates for ACL repair appear to be significantly higher than those for ACL reconstruction in people of all ages.

Current studies suggest that modern ACL repair techniques have a failure rate that may be five to ten times higher than that of ACL reconstruction1,2,3. One major recent study in a prominent sports medicine journal found that arthroscopic ACL repair has unacceptable outcomes in young athletes, with short-term failure rates of close to 50%2.

It has been suggested that ACL repair may be appropriate for older adults who have a type of ACL tear called a proximal avulsion and who do not participate in “cutting and pivoting” sports such as basketball, volleyball, and soccer. For these patients, failure rates in the short term appear to be much higher than ACL reconstruction in this age group1,2,3.

3. There is still much we don’t know about ACL repair.

There has been no scientific evidence that shows a difference in postoperative pain between ACL repair and reconstruction. Rehabilitation and return-to-play protocols for ACL repair have not yet been established. Proper guidelines for rehabilitation and return to sports are essential to keep people safe from re-injury.

Andrew D. Pearle, MD

Chief, HSS Sports Medicine Institute


Bryan T. Kelly, MD

HSS Surgeon-in-Chief and Medical Director


Answorth A. Allen, MD

David W. Altchek, MD

Struan H. Coleman, MD, PhD

Frank A. Cordasco, MD, MS

David M. Dines, MD

Joshua S. Dines, MD

Stephen Fealy, MD

Andreas H. Gomoll, MD

Lawrence V. Gulotta, MD

Jo A. Hannafin, MD, PhD

Anne M. Kelly, MD

John D. MacGillivray, MD

Robert G. Marx, MD, MSc, FRCSC

Michael J. Maynard, MD

Moira M. McCarthy, MD

Danyal H. Nawabi, MD, FRCS

Stephen J. O’Brien, MD, MBA

Anil S. Ranawat, MD

Scott A. Rodeo, MD

Howard Anthony Rose, MD

Beth E. Shubin Stein, MD

Sabrina M. Strickland, MD

Karen M. Sutton, MD

Samuel A. Taylor, MD

Russell F. Warren, MD

Thomas L. Wickiewicz, MD

Riley J. Williams III, MD



1. Jonkergouw A, van der List J, DiFelice G. Arthroscopic primary repair of proximal ACL tears: outcomes of the first 56 consecutive patients and the role of additional internal bracing. Knee Surg Sports Traumatol Arthrosc. 2019 Jan;27(1):21-28.

2. Gagliardi AG, Carry PM, Parikh HB, Traver JL, Howell DR, Albright JC. ACL repair with suture ligament augmentation is associated with a high failure rate among adolescent patients. Am J Sports Med. 2019 Mar;47(3):560-566.

3. Wright RW et al. Risk of tearing the intact ACL in the contralateral knee and rupturing the ACL graft during the first 2 years after ACLR: A prospective MOON cohort study. Am J Sports Med. 2007 Jul;35(7):1131-4.

For more information visit https://www.hss.edu/condition-list_torn-acl.asp.