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When Your ACL Goes Pop, St. Luke’s Orthopedic Care to the Rescue

ACL tear. We hear the term and think, oh no.

That was certainly the case in December when Carson Wentz, quarterback of the Philadelphia Eagles, tore the ACL in his right knee, ending his season.

The anterior cruciate ligament – ACL – is one of two cruciate ligaments, the other being the posterior cruciate ligament, and one of four ligaments in the knee. The other two, the medial collateral ligament and the lateral collateral ligament combine to help stabilize the knee in varying directions.

The ACL is a major contributor to knee function and stability. It prevents the knee from hyperextending – which places the other ligaments at risk – and stops the supporting shinbone – the tibia – from moving ahead of the thigh bone – the femur.

An ACL tear is one of the most well-known injuries in the sports world because it often requires surgery and, in the past, ended the athletic careers of many before modern techniques saved the day.

“ACL injuries are obviously pretty devastating for athletes and cause instability of the knee,” explains Dr. Nicholas Avallone, orthopedic surgeon with St. Luke’s Orthopedic Care.

 Nicholas J Avallone, MD

Nicholas J Avallone, MD


“In order for most athletes to participate in their sport, or even to do recreational activities such as skiing or even dancing, you rely upon your ACL to keep your knee stable,” he says. “There is a very small subset of people who can deal without their ACL, but they’re the exception, not the rule.”

ACL injuries can occur in a variety of ways. Surprisingly, most of these are non-contact injuries. A simple change in direction, a sudden stop while running, or landing from a jump can cause an ACL tear. A less common mechanism of injury occurs when an athlete’s knee is hit from the side with their foot planted.

Complications that may occur with an ACL tear include damage to the other ligaments, a torn meniscus, and even bone bruises.

Most people end up getting reconstructive surgery.

“We will fix those with minimally invasive arthroscopic surgery that is an outpatient procedure,” Dr. Avallone says. “We usually use the patient’s own tissue to make a new ACL, with a recovery that typically tales about nine months.”

After the surgery, physical therapy is required to strengthen the muscles surrounding the knee joint as well as return the joint to a normal range of motion.

When compared while playing the same sports such as basketball and soccer, girls are eight times more likely than boys to tear an ACL, although other research puts that as low as four times more likely, which is still alarming.

“Research is finding ACL injuries are not only more common among the female athletic population, particularly in a sport like soccer,” Dr. Avallone adds, “but more common for re-tears on the same side or tearing the ACL on the opposite side.”

Repairing a re-tear is called a revision, and Dr. Avallone says the surgical technique is a little different in those cases from a first-time surgery, but the outcomes appear to be just as successful.

When a knee injury occurs, athletic trainers do manipulation tests to assess the potential severity. An MRI will provide a complete look at what happened inside the knee and alert the orthopedic specialist to determine the best course of action for patient recovery.

Media Contact:

Brenda Hageter, Media Relations, (484)-526-3051, Brenda.hageter@sluhn.org

About St. Luke’s

Founded in 1872, St. Luke’s University Health Network is a fully integrated, regional, non-profit network of 14,000 employees providing services at 10 hospitals and over 315 outpatient sites.  With annual net revenue of $1.9 billion, the network’s service area includes 10 counties: Lehigh, Northampton, Carbon, Schuylkill, Bucks, Montgomery, Berks and Monroe counties in Pennsylvania and Warren and Hunterdon counties in New Jersey.  Dedicated to advancing medical education, St. Luke’s is the preeminent teaching hospital in central-eastern Pennsylvania.  In partnership with Temple University, St. Luke’s created the region’s first and only regional medical school campus.  It also operates the nation’s longest continuously operating School of Nursing, established in 1884, and 28 fully accredited graduate medical educational programs with 226 residents and fellows.  St. Luke’s is the only health care network in central-eastern Pennsylvania to earn Medicare’s five-star rating (the highest) for quality, efficiency and patient satisfaction.  Repeatedly, including 2018, St. Luke’s has earned the 100 Top Major Teaching Hospital and 50 Top Cardiovascular Program designations from IBM Watson Health (formerly Truven Health Analytics).  St. Luke’s, utilizing the EPIC electronic medical record (EMR) system, is a multi-year recipient of the Most Wired award recognizing the breadth of St. Luke’s information technology applications such as telehealth, online scheduling and online pricing information.  St. Luke’s is also recognized as one of the state’s lowest cost providers.