Still in Pain After ACL Repair? Supervised Rehab Superior to Exercises Alone

Young adult patients with persistent knee pain following anterior cruciate ligament (ACL) repair surgery got more relief from a supervised physical therapy program compared with self-directed rehab, results of a randomized trial indicated.

In the 184-patient trial, the supervised program improved Knee Injury and Osteoarthritis Outcome Score (KOOS) values by 14.1 points after 4 months, compared with a 9.4-point improvement with self-managed rehab (difference 4.8, 95% CI 1.4-8.2), according to Adam Culvenor, PhD, of La Trobe University in Bundoora, Australia, and colleagues.

By month 12, the self-managed control group largely caught up with those in the supervised program (change from baseline KOOS 14.5 and 15.8 points, respectively), the researchers reported in Annals of Internal Medicine.

With the 4-month results prespecified as the primary efficacy measure, that was enough for Culvenor and colleagues to write, “Physiotherapist-supervised exercise therapy and education is safe and should be recommended to improve the knee health of persons experiencing persistent knee problems after [ACL repair].”

An accompanying editorial was perhaps even more enthusiastic. “We can argue that more trials will be needed and that other comparators may be appropriate, but we have a population in need right now,” wrote Jeffrey Driban, PhD, of the UMass Chan Medical School in Worcester, Massachusetts, and Matthew Harkey, PhD, of Michigan State University in East Lansing.

“Two independent consensus statements have recommended that this population needs more education and supervised exercise,” they continued. “Culvenor and colleagues’ trial results offer a path forward that aligns with these recommendations, carries low risk, and addresses the short-term needs of these young adults.”

Reconstruction is the standard of care for severe ACL tears, and while it is effective, continued pain, activity limitations, and early-onset osteoarthritis in younger patients remains common. And yet, Culvenor’s group observed, “[d]espite the high burden, there are no evidence-informed interventions to guide clinical care for these young adults.”

In the months following surgery, patients are typically sent for some type of education and exercise-based rehabilitation. But whether supervision improves outcomes over giving patients a list of exercises to perform on their own — especially later on for those whose knees should have biologically healed — has never rigorously been tested.

Culvenor and colleagues enrolled 184 patients ages 18-40 who had undergone ACL surgery 9-36 months previously and had KOOS scores below 80 on the tool’s 100-point scale (higher values represent better health). That time span was chosen because 9 months after surgery is the typical period allowed for the repair to heal, and 36 months is considered the end of “the early transition period to posttraumatic osteoarthritis” when it may still be prevented, the researchers explained.

The intervention featured physiotherapist-led leg and neuromuscular exercises performed for 30-60 minutes twice weekly for the first 4 months, supplemented with a once-weekly unsupervised session. It also included education sessions lasting 45-60 minutes at weeks 1 and 4. In the control program, patients had one 30-minute education session at baseline and were given an instructional booklet with exercises to follow. Control patients could call the physiotherapist one time to ask questions about the exercises but received no other assistance from medical staff.

Patients were randomized 1:1 to the intervention or control program. All patients in the supervised program completed the first 4 months, while six in the control group were lost to follow-up. Five more in each group were lost at month 12. All were included in the final statistical analysis on an intention-to-treat basis using “all available data,” the researchers noted.

Mean patient age was about 30, and just under 40% were women. KOOS score at baseline averaged 64. A mean of 2.3 years had elapsed from surgery to enrollment. Surgical details varied among patients: for a few patients, the surgery was a revision, and small numbers had graft types other than hamstring tendon.

Secondary outcomes included the five KOOS subscales examined individually (pain, symptoms, daily activities, sports/recreation ability, and quality of life), knee muscle strength, and cartilage thickness and composition. The symptomatic and functional outcomes all strongly favored the supervised program at month 4, though only a few did so at month 12. Cartilage parameters didn’t differ between groups at either point.

Driban and Harkey, in the editorial, highlighted two findings that could easily be missed in the investigators’ report. Orthopedic surgeons generally consider a 9-point increase in KOOS score to be the minimal clinically important improvement; this was achieved by 74% of the intervention group at month 4, versus 51% of controls. Similarly, patients were asked to rate their improvement (or worsening) on a 7-point scale, from “much better” to “much worse,” with answers of “better” or “much better” classified as treatment success. Success by this measure was achieved in the intervention group at month 4 by 73% for pain and 83% for function, versus 40% and 43%, respectively, among controls.

That the two approaches yielded much more similar benefits at month 12 might be considered a strike against the more resource-intensive approach, but neither Culvenor’s group nor the editorialists saw it that way. Rather, both pointed to the earlier onset of improvements with the supervised program and the fact that they were sustained and even extended through month 12 as the more relevant interpretation.

Notably, neither group addressed the costs associated with the supervised program. Other limitations included potential that different results might have been achieved with other regimens and the lack of blinding. It was not possible to determine whether particular elements of the supervised program were more important than others in yielding the reported benefits.