The Cross-Bracing Protocol for ACL Injury – What is it?

Josh Craig

June 7, 2024

First things first, what is an ACL?

The anterior cruciate ligament (ACL) is a ligament in the knee which prevents anterior translation of the tibia and is normally compromised through large valgus and rotation forces. These movements can be replicated through activities such as jumping, landing and cutting. The ACL is one of the most commonly injured ligaments in the knee. Injury to the ACL is a common occurrence especially among athletes participating in sports that involve sudden stops, changes in direction, and jumping. Most ACL tears occur during non-contact mechanisms where the knee pivots, resulting in anterior translation of the tibia (shin bone) while the knee is slightly flexed and in a valgus (knock-knee) position (LaBella et al., 2014). When the ACL is torn, it can lead to instability, pain, and functional limitations. The prevalence of ACL ruptures has increased since the growth of women in sport, with women being 3-6 times more likely to sustain this injury than their male counterparts (Gould et al., 2016). To read more about ACL injuries in women click here to read our blog.

How have we been treating ACL ruptures?

The ‘gold standard’ management of an ACL rupture is currently surgery, as there is common belief that the ACL’s cannot heal. although considered the ‘gold-standard’ post surgical recovery is lengthy and often requires at least 10-12 months of structured rehabilitation to return to sport.

Recent research has shown the potential for the ACL to heal with non-surgical management, and a novel protocol that has gained attention in recent years is the Cross Bracing Protocol (Filbay et al., 2023).

Enter the Cross Bracing Method

This rehabilitation technique is designed to optimise healing of the ruptured ACL tissues by bracing the knee at 90 degrees flexion for 4 weeks, followed by 8 weeks of progressively increasing knee ROM and brace restrictions.

The ACL is most approximated with the knee flexed at 90 degrees, and the rationale for this protocol is to facilitate a “closed reduction” of the ACL by bridging the injured tissue between ruptured remnants (Filbay et al., 2023).

Is this an option for all ACL ruptures?

The short answer is no. There are strict inclusion and exclusion criteria associated with being a candidate for the cross bracing method. A summary of these criteria are below:

  • Structural concomitant injuries ie: bucket handle meniscus tear
  • History of DVT
  • Functionally able to tolerate period of knee mobilisation in flexion (this is a quite challenging position to have your knee locked in a brace at 90 degree bend for up to 6 weeks).
  • Has met MRI inclusion criteria
  • Able to commence bracing within 4-7 days of rupture (optimal)

Where does Physiotherapy fit in?

Physiotherapy is vital throughout the protocol, especially as the knee brace is progressively opened and knee range of motion is increased. Physiotherapy is integrated throughout the protocol which focusses on lower limb neuromuscular control, muscle strengthening and power, and functional training (Filbay et al., 2023). The brace is worn during rehabilitation exercises, and is gradually phased out as the individual progresses through the recovery process.

What are the studies saying?

90% of participants (72 out of 80) with ACL rupture showed ACL healing on MRI at 12-week follow-up, which in the past was thought to have limited healing capacity.

Greater ACL healing was associated with better knee function and quality of life, decreased knee laxity and a higher return-to-sport rate (Filbay et al., 2023). While this emerging evidence shows promising outcomes following non-surgical management, further research into the area of viable alternatives for ACL rehabilitation without invasive surgery is needed and longer term follow up to track this protocol’s efficacy over time.


Although this method is in its infancy, it is showing promising outcomes for preserving the ACL without the need for surgical intervention and putting a graft in with the ACL effectively ‘healing’ itself. Patient selection must be appropriate and a informed consent must be given with the understanding that there may still be a requirement for surgical reconstruction for some participants.

Grand Slam Physio works closely with local Sports Physicians to ensure correct bracing and rehab protocols are implemented for ACL injuries in both our Geelong and Torquay clinics.

Josh provides a summary on the Cross Bracing Method

About the Author

Josh Craig Physio

Josh holds both a Doctorate of Physiotherapy and Bachelor of Exercise Sports Science, and has had experience in both local and elite high-performance sport settings (GFL, Coates Talent League, VFL, Basketball Victoria). He is experienced in dealing with a range of sports injuries, orthopaedic and post-surgical rehabilitation, and chronic pain management.

Josh works from both our Geelong and Torquay clinics.


Filbay SR, Dowsett M, Chaker Jomaa M, et al. Healing of acute anterior cruciate ligament rupture on MRI and outcomes following non-surgical management with the Cross Bracing Protocol. Br J Sports Med. 2023;57(23):1490-1497. doi:10.1136/bjsports-2023-106931

Gould, S., Hooper J., Strauss E. (2016) Anterior Cruciate Ligament Injuries in Females: Risk Factors, Prevention, and Outcome, Bull Hosp Jt Dis, Vol 74 (1)

LaBella CR, Hennrikus W, Hewett TE; Council on Sports Medicine and Fitness, and Section on Orthopaedics. Anterior cruciate ligament injuries: diagnosis, treatment, and prevention. Pediatrics. 2014;133(5):e1437-e1450. doi:10.1542/peds.2014-0623