ACL Rupture: ‘’When I get that feeling, I want… ACL healing’’
Up until around 8 years ago, I was ambivalent towards ACL tear injury management, and even as a Masters-trained Senior Physiotherapist if pressed, probably assumed reconstruction was ‘gold standard’, as that’s what I’d read and seen everywhere.
It was 2 opposing cases I saw in quick succession as a trainee Specialist Physiotherapist that confronted me head on, forcing me to challenge any bias I had and avail myself to the best research literature (1).
1 of the patients had experienced 5 ACL surgeries, presenting to my clinic on a 4-wheeled-walker (which was incredibly odd for a woman in her mid-30’s). She was stressed, depressed, anxious, suicidal and had clearly not received adequate supervised post-op education and rehabilitation over the 4 years her operations had taken place.
The second patient had a fresh ACL and meniscus injury, who was adamant on commencing rehabilitation without surgery, as her sports teammates had experienced failed elective knee surgeries. We crafted a management plan in a shared decision-making context, began rehab and she returned to play at 4 months and at long-term follow-up remained sign and symptom free.
This forced me to question the orthodoxy that is ACL recon as ‘best practice’, spending 100’s of hours investigating the most credible evidence, with help from both Surgeon and Physiotherapist researchers and expert clinicians. What I discovered was that Westernised culture was flooded with a one-sided narrative of ACL reconstruction as the best first choice based on old bio-plausible, pathoanatomical paradigms, with this Global multibillion-dollar per annum gold-rush perpetually funded by governments, private insurance companies and commission-style private hospital sectors, with the best-evidence and patients falling second place (2).
Since that time, the ACL topic has absolutely mushroomed for me, whereby now I have overseen 1000’s of full thickness tears managed without surgery, including patients who have returned to high-level pivoting, jumping and cutting tasks.
Can ACL ruptures heal?
In the past 3 years, my management approach has shifted, due to a growing awareness of the healing capacity of ACL tears. I regularly see full thickness ruptures heal, with confirmation on repeat-MRI. This is a significant turn in clinical reasoning and management for me. A cursory Google search will reveal most initial websites suggesting “ACL tears never heal”, they have a “poor blood supply” and “surgery is necessary” to return to sports.
Fresh investigations have exposed online surgical advertising content by private elective orthopaedic groups targeted towards patients is frequently false or misleading (3, 4), over-estimating the benefits of surgery and under-estimating the harms (5), with calls for government regulators to intervene. We must wonder where the obsession with reconstruction experimentation will end, with kangaroo tendons and gold nanoparticles touted as the next big thing (6, 7).
A systematic review showed that ACL full thickness ruptures CAN heal, with strategies including bracing, rehabilitation and strengthening and even no management at all (8, 9).Shifting the burden of proof, the authors highlighted the revelation there are in fact no high-quality studies showing the ligament CAN’T heal! In a national debate on ACL tear management which I was a part of at the end of 2021, Physiotherapists, Surgeon researchers and expert clinicians agreed ACL tears can heal. Pilot data from Australia due to be released in 2022 was discussed, with over 90% of fully ruptured ACL’s healing with a novel bracing protocol, and long-term return-to-play achieved.
The ground-breaking KANON study revealed 58% of those who did not cross over to surgery had MRI proof of healing at 5-year follow-up (10). High healing rates have also been proven in partial tears with the use of a bracing protocol (11). Normalised anatomical, partial, lengthened ACL and non-anatomical (such as proximal ACL bundles attaching to the PCL) are all possible types of healing (12, 13, 14). Orthopaedic surgeon Andrea Ferretti stated that the ACL’s “blood supply.. is rich in vessels and anastomosis, providing adequate supply to all kinds and sites of tears,” with others recently suggesting increased blood supply following an ACL injury (15, 16).
Shared decision making
Shared-decision making is key here (17), meaning patients must be told their ACL tear may or may not heal as a part of their management options, although I do worry that in the ‘real world’ it is a pipe dream given our post-evidence-based era (18, 19). A Telehealth client of mine in 2021 saw a medical specialist who informed her that “a bomb had gone off in her knee,” her “knee had exploded” and her “only option and solution was surgery:” She had a partial ACL tear – talk about nocebo.
Not surprisingly, she burst into tears and under fear-mongered duress booked in for a reconstruction the following week. By chance, she was able to connect with me, we commenced a stabilisation protocol, with a follow-up MRI displaying near intact healing of the ligament; she returned to semi- professional soccer without surgery and at long-term follow-up is incredibly satisfied with her decision to wait and consider her options.
Figure 1: 28-year-old ACL-injured patient with an MRI at 1 week, and long-term follow-up (Park et al 2021)
In my experience, almost all patients aren’t given an objective shared decision-making process. This takes time (more than a 15-minute consult), care, empathy and empowerment of patients with current best guidelines, education aids, infographics and resources (20, 4). Communication has to be calm, unbiased and honest, with potential risks, harms and benefits of all treatment options clearly unpacked. A level-2 long-term cohort study showed incredibly high knee reinjury rates, with 2 out of 3 reconstructed patients suffering further damage after return-to-sport (2); these types of patients are often led to believe surgery is a “one-way ticket” to return to sport (22).
Studies of poor methodological quality, which retrospectively compare ACL reconstruction and rehab to non-controlled or absent comparison arms, and mechanistic-theory like ‘a graft-ACL acts like a normal ACL’ cannot be used to justify early reconstruction (23). A common purported misconception is that ACL reconstruction prevents greater rates of meniscal tears to non- surgical management (24). However, this evidence is considered as too weak to guide surgical treatment decisions (25). Both KANON and now the COMPARE randomised control trial have shown similar meniscal tear rates over time, with COMPARE actually showing higher future meniscal surgery in reconstructed patients (26, 27).
Who should have surgery?
We need to be advising all patients that the most empirical evidence shows no additional benefit of ACL reconstruction, meniscectomy or meniscal repair to rehabilitation alone for knee-injured patients, with no high-quality studies proving superiority of these techniques over exercise therapy treatment or placebo surgery (28). A Professor of Orthopaedic Surgery I met commented that he tells ACL and meniscus-injured patients “to go away and complete 6 to 12 months of rehabilitation on their knee” and he will then “operate on their knee if they aren’t satisfied” because he “can’t promise their knee will be better long-term for being operated on early.”
None of this is to say reconstruction is not a viable option for patients who have recurrent episodes of hard instability, despite an early administered high-quality stabilisation protocol; I have reiterated this in mass media interviews and have collegial connections with pragmatic orthopaedic surgeons who I collaborate with and share more in common with in managing musculoskeletal pain and injury, than not.
Physiotherapy leading ACL management
I believe Physiotherapists can be the leaders of managing ACL injuries in a triage role, which has been successfully implemented in musculoskeletal pain and injury primary care policy shifts in countries like Denmark and the UK, which can have a multiplicity of benefits to governments, private insurers, the medical system, patients, and clinicians alike (29).
Kiadaliri et al (2016) suggest savings of over $20,000 (AUD) in costs per patient through a fiduciary shift towards a Physiotherapy-led approach, reduce resource consumption and decrease risk of unnecessary overtreatment, even with the option of reconstruction, if needed (30). Interprofessionally, we need to all work together to design large, multicentre trials to assess healing capacity of ACL tears in various demographics, so patients can hopefully be triaged early, and significant amounts of money saved. If only this had been done 60 years ago, when the theory that ACL tears can’t heal was propagated based on animal models!
We as a profession will never be anti-surgery, but also need to represent patients as strong and confident expert non-surgical advocates by describing the best comparative evidence treating ACL and meniscus tears with exercise alone, weighed against surgery and exercise. If we won’t, who will?
Want to learn more from Kieran? Check out his ACL tear non-operative workshop HERE
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- Caneiro JP, Bunzli S, O’Sullivan P. Beliefs about the body and pain: the critical role in musculoskeletal pain management. Braz J Phys Ther. 2021;25(1):17-29. doi:10.1016/j.bjpt.2020.06.003
- Dhillon K. S. (2014). “‘Doc’ do I need an anterior cruciate ligament reconstruction? What happens if I do not reconstruct the cruciate ligament?”. Malaysian orthopaedic journal, 8(3), 42–47. https://doi.org/10.5704/MOJ.1411.010
- Ryan, H.Y., Sun, G.Y., Monuja, M., Gillespie, M., Burns, A., Solomon, M. and Adie, S. (2022), Adherence by orthopaedic surgeons to AHPRA and Australian Orthopaedic Association advertising guidelines. Med J Aust. https://doi.org/10.5694/mja2.51490
- Gamble AR, McKay MJ, Pappas E, et al. Online information about the management of anterior cruciate ligament ruptures in Australia: A content analysis [published online ahead of print, 2022 Mar 12]. Musculoskelet Sci Pract. 2022;59:102555. doi:10.1016/j.msksp.2022.102555
- Harris I. Surgery, The Ultimate Placebo: A Surgeon Cuts Through the Evidence. NewSouth Publishing 2016
- Power, J. Kangaroos could be the key to getting players like Alex Johnson back to full health.The Sydney Morning Herald. 2018
- Bellrichard M, Snider C, Kuroki K, Brockman J, Grant DA, Grant SA. The use of gold nanoparticles in improving ACL graft performance in an ovine model. Journal of Biomaterials Applications. 2022;36(6):1076-1086. doi:10.1177/08853282211039179
- Pitsillides A, Stasinopoulos D, Giannakou K. Healing potential of the anterior cruciate ligament in terms of fiber continuity after a complete rupture: A systematic review. J Bodyw Mov Ther. 2021;28:246-254. doi:10.1016/j.jbmt.2021.06.003
- Costa-Paz M, Ayerza MA, Tanoira I, Astoul J, Muscolo DL. Spontaneous healing in complete ACL ruptures: a clinical and MRI study. Clin Orthop Relat Res. 2012;470(4):979-985. doi:10.1007/s11999-011-1933-8
- Marangoni L, Murillo B, Bustos D, Bertiche P, Bitar I, Cabral D. Anterior Cruciate Ligament, Acute Tears. Spontaneus Healing, is True or False. Orthopaedic Journal of Sports Medicine. December 2018. doi:10.1177/2325967118S00204
- Filbay S, Roemer F, Lohmander S, et al32 Spontaneous healing of the ruptured anterior cruciate ligament: observations from the KANON trialBMJ Open Sport & Exercise Medicine 2022;8:doi: 10.1136/bmjsem-2022-sportskongres.8
- Park YG, Ha CW, Park YB, et al. Is it worth to perform initial non-operative treatment for patients with acute ACL injury?: a prospective cohort prognostic study. Knee Surg Relat Res. 2021;33(1):11. Published 2021 Apr 6. doi:10.1186/s43019-021-00094-3
- Jacobi M, Reischl N, Rönn K, Magnusson RA, Gautier E, Jakob RP. Healing of the Acutely Injured Anterior Cruciate Ligament: Functional Treatment with the ACL-Jack, a Dynamic Posterior Drawer Brace. Adv Orthop. 2016;2016:1609067. doi:10.1155/2016/1609067
- Nguyen, D.T., Ramwadhdoebe, T.H., van der Hart, C.P., Blankevoort, L., Tak, P.P. and van Dijk, C.N. (2014), Intrinsic healing response of the human anterior cruciate ligament: An histological study of reattached ACL remnants. J. Orthop. Res., 32: 296-301. doi.org/10.1002/jor.22511
- Crain EH, Fithian DC, Paxton EW, Luetzow WF. Variation in anterior cruciate ligament scar pattern: does the scar pattern affect anterior laxity in anterior cruciate ligament-deficient knees? Arthroscopy. 2005 Jan;21(1):19-24. doi: 10.1016/j.arthro.2004.09.015. PMID: 15650662.
- Ferretti A. To heal or not to heal: the ACL dilemma. J Orthop Traumatol. 2020;21(1):11.Published 2020 Aug 29. doi:10.1186/s10195-020-00554-8
- Takeuchi S, Rothrauff BB, Kanto R, Onishi K, Fu FH. Superb microvascular imaging (SMI) detects increased vascularity of the torn anterior cruciate ligament. Knee Surg Sports Traumatol Arthrosc. 2022;30(1):93-101. doi:10.1007/s00167-021-06640-6
- Elwyn G, Frosch DL, Kobrin S. Implementing shared decision-making: consider all the consequences. Implement Sci. 2016;11:114. Published 2016 Aug 8. doi:10.1186/s13012-016-0480-9
- Greenhalgh T, Howick J, Maskrey N. Evidence based medicine: a movement in crisis? BMJ 2014; 348 :g3725 doi:10.1136/bmj.g3725
- Jureidini J, McHenry L B. The illusion of evidence based medicine BMJ 2022; 376 :o702 doi:10.1136/bmj.o702
- Gleadhill CP, Barton CJ. Infographic. ACL injury journey: an education aid. Br J Sports Med. 2021;55(12):697-698. doi:10.1136/bjsports-2020-102273
- Filbay SR, Grindem H. Evidence-based recommendations for the management of anterior cruciate ligament (ACL) rupture. Best Pract Res Clin Rheumatol. 2019 Feb;33(1):33-47. Doi: 10.1016/j.berh.2019.01.018. Epub 2019 Feb 21. PMID: 31431274; PMCID: PMC6723618.
- Fältström A, Kvist J, Hägglund M. High Risk of New Knee Injuries in Female Soccer Players After Primary Anterior Cruciate Ligament Reconstruction at 5- to 10-Year Follow-up. The American Journal of Sports Medicine. 2021;49(13):3479-3487. doi:10.1177/03635465211044458
- Zadro JR, Pappas E. Time for a Different Approach to Anterior Cruciate Ligament Injuries: Educate and Create Realistic Expectations. Sports Med. 2019;49(3):357-363. doi:10.1007/s40279-018-0995-0
- Sanders TL, Pareek A, Kremers HM, et al. Long-term follow-up of isolated ACL tears treated without ligament reconstruction. Knee Surg Sports Traumatol Arthrosc. 2017;25(2):493-500. doi:10.1007/s00167-016-4172-4
- Filbay SR. Early ACL reconstruction is required to prevent additional knee injury: a misconception not supported by high-quality evidence. British Journal of Sports Medicine 2019;53:459-461.
- Ekås GR, Ardern CL, Grindem H, Engebretsen L. Evidence too weak to guide surgical treatment decisions for anterior cruciate ligament injury: a systematic review of the risk of new meniscal tears after anterior cruciate ligament injury. Br J Sports Med. 2020;54(9):520-527. doi:10.1136/bjsports-2019-100956
- Frobell RB, Roos HP, Roos EM, Roemer FW, Ranstam J, Lohmander LS. Treatment for acute anterior cruciate ligament tear: five year outcome of randomised trial. BMJ. 2013;346:f232. Published 2013 Jan 24. doi:10.1136/bmj.f232
- Reijman M, Eggerding V, van Es E, et al. Early surgical reconstruction versus rehabilitation with elective delayed reconstruction for patients with anterior cruciate ligament rupture: COMPARE randomised controlled trial. BMJ. 2021;372:n375. Published 2021 Mar 9. doi:10.1136/bmj.n375
- Blom AW, Donovan RL, Beswick AD, Whitehouse MR, Kunutsor SK. Common elective orthopaedic procedures and their clinical effectiveness: umbrella review of level 1 evidence. BMJ. 2021;374:n1511. Published 2021 Jul 7. doi:10.1136/bmj.n1511
- Lewis JS, Cook CE, Hoffmann TC, O’Sullivan P. The Elephant in the Room: Too Much Medicine in Musculoskeletal Practice. J Orthop Sports Phys Ther. 2020;50(1):1-4. doi:10.2519/jospt.2020.0601
- Kiadaliri AA, Englund M, Lohmander LS, Carlsson KS, Frobell RB. No economic benefit of early knee reconstruction over optional delayed reconstruction for ACL tears: registry enriched randomised controlled trial data. Br J Sports Med. 2016;50(9):558-563. doi:10.1136/bjsports-2015-095308
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If you have a question, suggestion or a link to some related research, share below!
I had a Grade 3 ACL 2 weeks ago, 31 December 2022. I am really scared to go for a surgery, Is conservative will work for me? I would rather opt for a life time commitment exercise rather than having surgery. Please advise.
the future will be interesting indeed. for now, i do think that simple acl tears (without concurrent meniscal and MCL injuries) would have a better chance of healing and .: respond better to rehab. would be great to find out what populations do heal and to eventually have a protocol for it (i.e. bracing and some triage for who should go to surgery – likely failed conservative management cases). I guess the elite athletes often do not have the time to see if conservative management will work before doing a surgery as they are often a limited time schedule.
Great blog! Thank you. My ACL took about 1 year, but my first 4 months were focused on rehabilitation of 12 spinal fractures, so it may have been a little sooner if specific rehab was started earlier.
This is great information!!
But you missed our scientific evidence!
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