Do I need to have surgery for an ACL tear? A 2026 update- By Michael Phipps (Titled Sports and Exercise Physiotherapist)

State of the nation 

Australia has a rising incidence of anterior cruciate ligament (ACL) injuries, with the highest growth rate (10.4% per year) seen in girls aged 5 to 14 (Maniar et al., 2022). Surgery rates are rising too, with ACL reconstructions in people under 25 increasing by a whopping 74% between 2000 and 2015. In fact, Australia has the highest rate of ACL surgical reconstruction in the world, with an incidence of 77.4 per 100,000 people compared to 52 in the USA and 37 in New Zealand (Zbrojkiewicz et al., 2018). It raises a question: is surgery both necessary and optimal? 

What is the evidence for treating an ACL tear without surgery? 

Reconstructive surgery has historically been considered the treatment of choice for a torn ACL; however, emerging evidence challenges this viewpoint. The KANON trial randomised young, active adults to either early reconstruction or rehabilitation with the option of surgery later (Frobell et al., 2010). There was no difference in pain, function, sport or quality of life at 2, 5 or 11 years, and around half of the rehabilitation group never had surgery (Frobell et al., 2013; Lohmander et al., 2023). If anything, signs of arthritis on X-ray were slightly more common after early surgery. 

Another two trials and a systematic review add to the picture. The COMPARE trial found a small advantage for early surgery of unclear clinical importance (Reijman et al., 2021), and a living systematic review found no clinically important difference between the two approaches (Saueressig et al., 2022). The exception is people whose knee is still giving way months after injury, who did better with surgery in the ACL SNNAP trial (Beard et al., 2022). 

The evidence supports rehabilitation as a legitimate first-line option for many people, but if your knee continues to give way despite a good bout of rehabilitation, surgery should be considered. 

Can an ACL actually heal? 

Yes, sometimes. In the KANON trial, MRI (magnetic resonance imaging) showed the ACL had healed (become continuous again) in 30% of the rehabilitation group at 2 years and in 53% of those who never had surgery, and people whose ACL healed reported better knee function and quality of life (Filbay, Roemer, et al., 2023). 

Bracing an ACL tear to help it heal is not a new idea, with Japanese surgeons reporting on it for more than 20 years (Fujimoto et al., 2002). In one study of 102 people braced for 3 months, around 57% showed good healing on MRI and, interestingly, healing was far more common in those aged 20 and over (73%) than in those under 20 (31%) (Ihara & Kawano, 2017). 

The Cross Bracing Protocol builds on this. The knee is braced at 90 degrees of bend so the torn ends sit closer together, and the brace is gradually unlocked over 6 to 12 weeks alongside rehabilitation. In the first published group of 80 people, 90% had a continuous ACL on MRI at 3 months (Filbay, Dowsett, et al., 2023). The protocol is still evolving, with shorter and "hybrid" versions now used depending on the person and their MRI, and the brace ideally needs to go on within 4 to 10 days of injury (Cross Bracing Protocol, 2025). 

Does a healed ACL mean a stable knee? 

Not always. In the Cross Bracing study, 14% of people re-ruptured their ACL (Filbay, Dowsett, et al., 2023), and in the KANON trial, healed ACLs were more likely to show laxity (looseness) on testing than reconstructed ones (Filbay, Roemer, et al., 2023). At 11 years, the small group of 14 people whose ACL looked continuous at 5 years actually reported worse outcomes than those who had a reconstruction (Filbay et al., 2025). 

A 2026 study also reported that 70% of pivoting athletes who chose bracing had their knee give way again within 2 years, compared with 2.5% after surgery (Porter & Shadbolt, 2026). However, the study has important flaws: patients chose their own treatment rather than being randomised, it excluded the complete ruptures on MRI that the original bracing study included, and bracing could start up to 6 weeks after presentation rather than within the recommended 4 to 10 days. 

It is very clear that not all ACLs heal, and a healed ACL on MRI is not the whole story. This does, and does not matter; you can have a great outcome without your ACL healing. The EMBRACE trial, comparing the Cross Bracing Protocol with early reconstruction in 180 people aged 16 to 40, is currently recruiting and should give us clearer answers in a few years (University of Melbourne, 2025). 

I've torn my ACL, what should I do? 

It depends. An individual's goals, life circumstances, general health, sporting level, age, and physical functioning all play a role in deciding if surgery or rehabilitation is the best option. It is important to emphasise that certain individuals do require and benefit from surgery (particularly some people with a concurrent meniscus injury); however, a significant portion of people can have an equivalent outcome with a physiotherapist-led rehabilitation program. If your child has torn their ACL, open growth plates add an extra layer to the decision. 

When I see someone with an ACL tear, we start with how the injury happened and what you want to get back to, whether that is football or basketball, chasing your kids, or a physically demanding job. I assess your knee, go through your MRI with you (or discuss whether you need one), and we make a shared decision between rehabilitation first, bracing or surgery. 

Whichever pathway you choose, rehabilitation does the heavy lifting. It should resemble a criterion-based plan, where you progress by meeting set benchmarks rather than by the number of weeks since injury. This should include resistance training, and graded movements (such as plyometrics and landing drills) to return to your chosen activity. To me, recovered does not mean a perfect MRI. It means playing a full game without thinking about your knee, or squatting down to pick up your toddler, with strength to match your other leg. 

If you have injured your knee, torn your ACL, or are tossing up between surgical and non-surgical options, book an consultation with Michael at Total Physiotherapy Sydney for a comprehensive assessment. 

This article is general information only and is not a substitute for a individualised advise or assessment. 

References 

Beard, D. J., Davies, L., Cook, J. A., Stokes, J., Leal, J., Fletcher, H., Abram, S., Chegwin, K., Greshon, A., Jackson, W., Bottomley, N., Dodd, M., Bourke, H., Shirkey, B. A., Paez, A., Lamb, S. E., Barker, K., Phillips, M., Brown, M., . . . [PRACTITIONER: final author]. (2022). Rehabilitation versus surgical reconstruction for non-acute anterior cruciate ligament injury (ACL SNNAP): A pragmatic randomised controlled trial. The Lancet, 400(10352), 605–615. https://doi.org/10.1016/S0140-6736(22)01424-6 

Cross Bracing Protocol. (2025). Clinician information booklet [Brochure]. https://crossbracingprotocol.com/wp-content/uploads/2025/09/CBP-Clinician-Information-Booklet-v1.3_compressed.pdf 

Filbay, S. R., Dowsett, M., Chaker Jomaa, M., Rooney, J., Sabharwal, R., Lucas, P., Van Den Heever, A., Kazaglis, J., Merlino, J., Moran, M., Allwright, M., Kuah, D. E. K., Durie, R., Roger, G., Cross, M., & Cross, T. (2023). Healing of acute anterior cruciate ligament rupture on MRI and outcomes following non-surgical management with the Cross Bracing Protocol. British Journal of Sports Medicine, 57(23), 1490–1497. https://doi.org/10.1136/bjsports-2023-106931 

Filbay, S. R., Roemer, F., Roos, E. M., Turkiewicz, A., Frobell, R., Lohmander, L. S., & Englund, M. (2025). Association between ACL continuity on magnetic resonance imaging at 5 years after an acute ACL rupture and 11-year outcomes: A secondary analysis from the KANON trial. The American Journal of Sports Medicine, 53(8), 1893–1900. https://doi.org/10.1177/03635465251339061 

Filbay, S. R., Roemer, F. W., Lohmander, L. S., Turkiewicz, A., Roos, E. M., Frobell, R., & Englund, M. (2023). Evidence of ACL healing on MRI following ACL rupture treated with rehabilitation alone may be associated with better patient-reported outcomes: A secondary analysis from the KANON trial. British Journal of Sports Medicine, 57(2), 91–99. https://doi.org/10.1136/bjsports-2022-105473 

Frobell, R. B., Roos, E. M., Roos, H. P., Ranstam, J., & Lohmander, L. S. (2010). A randomized trial of treatment for acute anterior cruciate ligament tears. The New England Journal of Medicine, 363(4), 331–342. https://doi.org/10.1056/NEJMoa0907797 

Frobell, R. B., Roos, H. P., Roos, E. M., Roemer, F. W., Ranstam, J., & Lohmander, L. S. (2013). Treatment for acute anterior cruciate ligament tear: Five year outcome of randomised trial. BMJ, 346, Article f232. https://doi.org/10.1136/bmj.f232 

Fujimoto, E., Sumen, Y., Ochi, M., & Ikuta, Y. (2002). Spontaneous healing of acute anterior cruciate ligament (ACL) injuries – conservative treatment using an extension block soft brace without anterior stabilization. Archives of Orthopaedic and Trauma Surgery, 122(4), 212–216. https://doi.org/10.1007/s00402-001-0387-y 

Ihara, H., & Kawano, T. (2017). Influence of age on healing capacity of acute tears of the anterior cruciate ligament based on magnetic resonance imaging assessment. Journal of Computer Assisted Tomography, 41(2), 206–211. https://doi.org/10.1097/RCT.0000000000000515 

Lohmander, L. S., Roemer, F. W., Frobell, R. B., & Roos, E. M. (2023). Treatment for acute anterior cruciate ligament tear in young active adults. NEJM Evidence, 2(8), Article EVIDoa2200287. https://doi.org/10.1056/EVIDoa2200287 

Maniar, N., Verhagen, E., Bryant, A. L., & Opar, D. A. (2022). Trends in Australian knee injury rates: An epidemiological analysis of 228,344 knee injuries over 20 years. The Lancet Regional Health – Western Pacific, 21, Article 100409. https://doi.org/10.1016/j.lanwpc.2022.100409 

Porter, M. D., & Shadbolt, B. (2026). Cross Bracing Protocol for anterior cruciate ligament (ACL) rupture has unacceptably high failure rate relative to surgical stabilization: A 2-year controlled cohort study. Clinical Journal of Sport Medicine, 36(4), 444–450. https://doi.org/10.1097/JSM.0000000000001416 

Reijman, M., Eggerding, V., van Es, E., van Arkel, E., van den Brand, I., van Linge, J., Zijl, J., Waarsing, E., Bierma-Zeinstra, S., & Meuffels, D. (2021). Early surgical reconstruction versus rehabilitation with elective delayed reconstruction for patients with anterior cruciate ligament rupture: COMPARE randomised controlled trial. BMJ, 372, Article n375. https://doi.org/10.1136/bmj.n375 

Saueressig, T., Braun, T., Steglich, N., Diemer, F., Zebisch, J., Herbst, M., Zinser, W., Owen, P. J., & Belavy, D. L. (2022). Primary surgery versus primary rehabilitation for treating anterior cruciate ligament injuries: A living systematic review and meta-analysis. British Journal of Sports Medicine, 56(21), 1241–1251. https://doi.org/10.1136/bjsports-2021-105359 

University of Melbourne. (2025). Cross Bracing Protocol versus surgery for acute anterior cruciate ligament rupture (Identifier NCT06956339). ClinicalTrials.gov. https://clinicaltrials.gov/study/NCT06956339 

Zbrojkiewicz, D., Vertullo, C., & Grayson, J. E. (2018). Increasing rates of anterior cruciate ligament reconstruction in young Australians, 2000–2015. Medical Journal of Australia, 208(8), 354–358. https://doi.org/10.5694/mja17.00974