Old ACL Injury: Go Straight to OR, Skip Preop Rehab?

For longstanding anterior cruciate ligament (ACL) injury (note the key word: “longstanding”), says a team from Oxford University in the UK, it’s better to head straight to surgery rather than undergoing rehabilitation first (and then surgery). The work is published in the August 20, 2022, edition of The Lancet. The study is titled the Anterior Cruciate Ligament SNNAP (Surgery Necessity in Non-Acute Patients) trial.

David Beard, lead author and professor of Musculoskeletal and Surgical Science at the Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences said to OTW, “This work has been needed for a while as it addresses a different group of ACL injured people to those in previous large scale practice changing trials and adds to the overall jigsaw of how best to treat the injury at different stages of presentation and time from injury. However, with recent waiting lists for elective surgery (especially orthopaedics) at an all-time high in most places (in the National Health Service), the findings are even more pertinent. In this case it seems that delaying or offering other forms of treatment, a common theme in a waiting list laden system, is not as effective as undergoing surgery.”

The study team collected data from 316 patients at 29 orthopedic centers in the UK between 2017 and 2020, with patients randomly assigned to either a surgical reconstruction group or to a group undergoing initial rehabilitation with surgery at a later time.

At the 18-month mark, patients were asked to report on pain, activity levels, secondary issues, satisfaction, and functionality of the knee.

The mean Knee Injury and Osteoarthritis Outcome Score (KOOS4) at 18 months was 73.0 in the surgical group and 64.6 in the rehabilitation group (on scale of 100). A higher score indicates greater pain relief and joint function.

The adjusted mean difference was 7.9 in favor of surgical management. A total of 65 (41%) of 160 patients allocated to rehabilitation underwent subsequent surgery. A total of 43 (28%) of the 156 patients allocated to surgery did not undergo the procedure.

“This research does not refute or replace the previous research work from Scandinavia and the Netherlands advising that acute ACL injured patients should likely undergo a period of rehabilitation first, before considering surgery,” commented Dr. Beard to OTW. “The findings only apply to longer-standing ACL injured patients. Trial results can sometimes be taken out of context and applied incorrectly (wrong group for example) and sometimes for ulterior motives—we must guard against that.”

“As a trialist of complex interventions who is passionate about finding the truth and showing benefit where it exists (including surgery), it is particularly useful to have an independent study showing the value of surgery for once too. There has been a strong recent appetite for surgical research that focuses on procedures with suspected poor efficacy and de-implementation (which of course is also needed), but a lack of balance here can create research engagement barriers. The surgical community (again especially in orthopaedics) should be applauded for their ongoing engagement in outcomes research and studies (such as Surgery Necessity in Non-Acute Patients), and the trial shows that positive studies of surgical effectiveness can be delivered.”

“There is also a positive message for the physios and rehabilitation experts. The trial still shows benefit in non-operated patients and non-surgical treatment should remain an option if thought appropriate for long standing ACL injured patients. The trial should not be used to take anything ‘off the shelf’, but merely to provide better clinical guidance for patients and clinicians in a shared decision-making environment. It may also facilitate and promote a focus on the rehabilitation following reconstructive surgery—after all, the outcome of the surgery is only as good as the subsequent rehabilitation.”