ACL Surgery May Lead to Arthritis Symptoms, Says Study

Each year, there are almost 400,000 anterior cruciate ligament (ACL) reconstructive surgeries in the United States. A new study shows preventive measures are needed to halt arthritis symptoms following ACL surgery.

The investigation from Michigan State University published in the Journal of Athletic Training found nearly one-quarter of patients in their study battled osteoarthritis in the knee shortly after an ACL procedure.

First of all, what is the ACL? Known as the most commonly injured knee ligament, according to Cleveland Clinic, it is one of four ligaments in each knee. The ACL connects to the thigh bone (femur) and shin bone (tibia) and serves as a strap that connects to bones and prevents the knee from over-rotation. Any unnatural movement of the ACL may result in an injury or tear.

An ACL injury is categorized into three grades of severity, with grade 1 being more of a strain since the ligament is still intact. Grade 2 is a partially torn ACL, while grade 3 is a complete tear of the ligament which often requires reconstructive surgery.

ACL tear symptoms include:

• Pop in the knee sensation.
• Pain when putting weight on the knee.
• Weakness in the knee.
• Poor range of motion in the knee.

ACL surgeries and arthritis symptoms

The study from Michigan State evaluated 82 participants between the ages of 13-35 who underwent unilateral primary ACL reconstruction. Researchers sought to discover if early osteoarthritis was present six to 12 months following surgery.

The U.S. Centers for Disease Control and Prevention says osteoarthritis is the most common form of arthritis, known as “wear and tear.” The condition occurs when cartilage within a joint begins to break down and affects the underlying bone. Over time, osteoarthritis can cause pain, stiffness, and swelling.

Matthew Harkey, the study author and an assistant professor in the Department of Kinesiology at Michigan State, said in a university release that he is hopeful his research can bring attention to osteoarthritis symptoms following ACL injuries. After all, many of those who suffer severe ACL injuries are young athletes competing in various sports.

“We’re trying to change the narrative,” Harkey said. “We see fairly young, active individuals experiencing extensive symptoms, but these symptoms are not interpreted by clinicians as something that may be related to osteoarthritis. Ignoring these symptoms might be setting them up to experience long term decline and function.”

Harkey and his team found that 22% of participants displayed early osteoarthritis symptoms during both visits, around six and 12 months following surgery. From the first to the second follow-up visit, 18-27% have relief of early osteoarthritis symptoms. Researchers note that 48-51% of participants had no early signs of osteoarthritis.

Harkey doesn’t say these osteoarthritis symptoms will lead to early osteoarthritis, however, it highlights the need for physical therapists to be aware of the possibility of symptoms.

“It’s a bit complex – we can’t outright say arthritis is developing, but there’s a large group of patients whose symptoms linger long after surgery,” Harkey said in a release. “Often, clinicians assume that these post-operative symptoms will naturally improve as patients reengage with their usual activities. However, what we’re seeing suggests these symptoms persist and likely require a targeted approach to manage or improve them.”

Steps for recovery after ACL surgery

The University of California San Francisco provides recommendations to help those with ACL surgeries prevent adverse symptoms and aid recovery. UCSF says to rotate both ankles up and down 10 times every 10 minutes for up to three days following surgery to prevent blood clots from developing.

Also, keep the operated leg elevated 12 inches above the heart at a 45-degree angle for three to five days following surgery. Try to incorporate slow knee-bending exercises to help gain a 0-to-90-degree range of motion by the first follow-up a week after surgery. It is important to watch for a fever following surgery and take pain medication like ibuprofen or acetaminophen to aid recovery. Stronger painkillers can be obtained with doctors' approval.

The rehab process begins one to two weeks after ACL surgery. During this time, it is important to follow professional advice to prevent re-injury. UCSF says don’t run or swim for the first five months. Focus on stationary bike riding or lightweight leg exercises for the first three months following surgery. It takes six to nine months to recover from ACL surgery.

For those who suspect an ACL injury, make sure to follow the R.I.C.E. method as soon as symptoms are noticed. This includes resting the knee, icing for 15 minutes at a time a few times per day, compressing the knee with a bandage to reduce swelling, and elevating the knee above the heart as often as possible.