Immediate Versus Optional Delayed Surgical Repair for Treatment of Acute ACL Injuries (IODA)

Comparison of Immediate Versus Optional Delayed Surgical Repair for Treatment of Acute Anterior Cruciate Ligament Injury Through a Parallel, Multicentric, Pragmatic Randomized Controlled Trial

Belgian Health Care Knowledge Centre, Jessa Ziekenhuis Hasselt, Centre Hospitalier Universitaire de Liege, CHC Montlegia, Clinique Saint-Luc Bouge

Currently, most patients with an anterior cruciate ligament injury undergo surgery. There is a general belief that surgical reconstruction is necessary to safely return to sports and to prevent early knee osteoarthritis or additional meniscus injuries. But there is insufficient scientific evidence to support this belief. Moreover, several studies show that surgical reconstruction of the cruciate ligament does not guarantee successful return to sports or the prevention of osteoarthritis and secondary meniscus injuries. Therefore, immediate surgery after an anterior cruciate ligament injury is questioned. So far, only two RCTs (KANON study and COMPARE study) have assessed this, and they could not show that immediate reconstruction is an added value (in terms of symptoms, knee function, activity level, osteoarthritis or additional meniscal injuries) compared to a conservative approach consisting of rehabilitation and late surgery for persistent knee instability. Therefore, this additional multicenter RCT, aims to 1) verify these results and 2) to identify predictors that predict which patients in the conservative group will not require late surgery. This has not been investigated to date. It is suspected that factors such as symptoms, strength, findings on the MRI scan and psychological factors may play a role in whether or not a patient will be able to successfully rehabilitate without surgical repair. This information is invaluable to physicians because it allows them to decide which treatment is best for the patient.

All patients complete rehabilitation under supervision of their own physiotherapist. The investigators will provide some guidelines and criteria, but it is the physiotherapist's choice how to implement these guidelines in clinical practice.

If a patient complains about persistent symptomatic instability of the knee or the inability to progress in rehabilitation, delayed surgery can be considered. ACL insufficiency induced instability in combination with a positive pivot shift and an additional MRI are needed to confirm the cause of instability. This surgery will not be performed within the first 12 weeks after the ACL injury.

No guidelines on type of ACL reconstruction will be imposed to keep the trial pragmatic. The decision of graft type and surgery technique is a clinical decision made by the orthopaedic surgeons of the participating centra. This surgery will be performed within 12 weeks after the ACL injury.

Knee Injury and Osteoarthritis Outcome Score - Subscale Quality of Life (score between 0-100, higher scores mean better outcome)

Knee Injury and Osteoarthritis Outcome Score - Subscale Quality of Life (score between 0-100, higher scores mean better outcome)

Prediction analysis to identify patient-specific factors that predict whether (or not) a patient will require delayed surgery

Dependent variable = whether or not delayed surgery is performed (binary event) Independent variables (candidate predictors): Knee Injury and Osteoarthritis Outcome Score - Subscale Quality of Life at baseline MRI findings at baseline scored with the modified ACLOAS (Anterior Cruciate Ligament OsteoArthritis Score) Degree of hemarthrosis determined by MRI at baseline Expectations regarding the effectiveness of physical therapy at baseline, measured with the illness perception questionnaire Pre-injury activity level, measured with the Tegner Activity Score

Inclusion Criteria: Rotational trauma to a knee that had no previous serious injury and for which medical advice was sought within 4 weeks after the injury. Medical diagnosis of ACL insufficiency including MRI (both partial and complete ruptures) Minimum of 16 years Exclusion Criteria: Participant has a history of a previous ACL injury or knee surgery to the index knee Indication for acute surgery because of related injuries to the knee Female who is pregnant or plans to become pregnant in the first 4 months of the trial. Since MRI assessment cannot be performed.