Can a Torn ACL Heal Without Surgery? Early Evidence From the Cross Bracing Protocol

For decades, the ruptured anterior cruciate ligament was considered incapable of healing, making reconstruction the default for active patients. Filbay and colleagues' 2023 study in the British Journal of Sports Medicine tested a different premise: that if the torn ligament ends are approximated early — by immobilising the knee at 90 degrees of flexion, where the ACL fibres sit closest together — the ligament may heal.

The researchers reported on 80 consecutive patients managed within four weeks of acute ACL rupture using the Cross Bracing Protocol: four weeks of knee immobilisation at 90 degrees in a range-of-motion brace, progressive increases in knee motion until brace removal at 12 weeks, and physiotherapist-supervised, goal-oriented rehabilitation throughout.

At three months, 90% of patients showed evidence of ACL healing on MRI. Patients whose ligaments healed with more continuous tissue reported better knee function and quality-of-life outcomes, and a substantial majority returned to pre-injury sport within 12 months. These are striking findings, but the study design demands caution. This was a case series without a comparison group, so it cannot establish that the protocol outperforms early rehabilitation alone or surgical reconstruction. The protocol itself evolved during the study after deep vein thrombosis events, leading to the addition of prophylactic anticoagulation, and twelve weeks of bracing is a significant physical and practical burden.

The practical takeaway is not that bracing should replace surgery, but that ACL healing is biologically possible in many acute ruptures and that non-operative pathways deserve serious, structured consideration. Randomised trials now underway will clarify where this protocol fits relative to reconstruction and standard rehabilitation.

Key findings

• Eighty consecutive patients within four weeks of acute ACL rupture were managed non-surgically with the Cross Bracing Protocol: knee immobilisation at 90 degrees of flexion for four weeks, graded increases in range of motion until brace removal at 12 weeks, and supervised goal-oriented rehabilitation.
• Ninety percent of patients showed evidence of ACL healing on MRI at three months.
• Patients with more continuous ACL healing on MRI reported better outcomes, and a majority returned to their pre-injury sport within 12 months.
• This is a case series, not a randomised trial; the protocol evolved after early deep vein thrombosis events (anticoagulation was subsequently added), and prolonged bracing carries meaningful burdens and risks.
• Findings are hypothesis-generating and are being tested in randomised trials before this can be considered a standard alternative to reconstruction.

Clinical relevance

Clinicians counselling patients after acute ACL rupture need current, balanced information on non-operative options; this study reframes the surgery conversation while underscoring the need for careful patient selection and monitoring.

Prepared by the Volt Health team as an educational summary of the cited publication. It is not medical advice; assessment and treatment decisions should always be made with a qualified health professional.