ACL (cruciate) tears: surgery or not?

December 16, 2024 / anne brennan

Sports fans recognise this gut-wrenching scenario. A football match is being televised when, suddenly, the action stops. A young athlete is on the ground clutching their knee. The replay shows that they were brought down by a knee twisting action perhaps from a tackle or landing awkwardly from a mark. Commentators begin to speculate on whether they have ‘done their cruciate.’ Or perhaps: done it again. Even before the unfortunate young athlete is carted off, the commentators are pondering how long it will take them to get back to play after reconstruction surgery. If they are to be believed, surgery is inevitable.

Worldwide, the number undertaking ACL repair /reconstruction surgery is increasing. In Australia Anterior Cruciate Ligament (ACL) tears are a common problem for young women playing Australian Rules football.

The ACL is a tough ligament that crosses from the front of the top of the tibia (shin bone) to the back of the femur (thigh bone) within the knee joint. It stops the tibia sliding forward. It is also important for proprioception (balance sense). It crosses the posterior ligament which explains the name cruciate (meaning crosses). If ruptured, the knee joint can become unstable. Using an ‘anterior draw test’, a tester can pull the lower leg further forward from the thigh than is normal.

Researchers have wondered if surgery leads to more problems down the line. These include tightness, loss of proprioception due to interference with the tendon [1] recurring inflammation and/or, in the long term, arthritis [2, 3].

After surgery, 1 in 5 suffer reinjury to either the repaired or other knee [4]. Around 10-15% ‘fail’ in the short-term while long-term failure may be as high as 27% [5, 6] .

For many years now, researchers from the Swedish KANON trials have been investigating whether exercises that retrain agility, balance and proprioception as well as strength can be more effective, with less side effects, than surgery, and/or can help surgical outcomes [7, 8]. Surprisingly perhaps, research has shown that this ligament can heal [9].

Treatment that includes exercise (rather than surgery) and/or rest to promote healing is, unsurprisingly, controversial with surgeons. One surgeon, quoted in the NBC health news, said it was ‘malpractice’. Strong words but there is little evidence to support his belief [10]. There is no convincing evidence that surgery prevents further damage nor long term pain/arthritis as is claimed [3, 9].

There is, however, an argument that undergoing expensive, invasive surgery that can fail painfully, without first trying alternatives, is more harmful.

On that note, the KANON group are beginning to score goals.

One KANON study, led by Dr Stephanie Filbay from the Centre for Health, Exercise and Sports Medicine (CHESM) at the University of Melbourne, found that in 90% of ACL tears in 80 participants (mostly athletes) treated with, initally, rest and braces then carefully reintroduced exercise, most ACLs repaired themselves. Many in the trial reported good knee stability and function, and were able to return to their sport a year later [11].

Research has highlighted, however, that not all ACL tears are equal: the degree of damage can vary and is a factor in recovery or the decision whether to undergo surgery [12, 13].

CHESM has put out a helpful, on line guide to treatment options. They suggest an exercise rehabilitation trial before surgery. Why not? Even if you (or the patient) decides to go ahead with surgery, exercise beforehand can only help[13].

This is from the CHESM website:

‘Postponing the decision to have surgery does not result in worse outcomes compared to having surgery right after the injury. Research suggests that performing rehab for 1 to 6 months before surgery improves knee strength and function after surgery.’ (https://www.aclinjurytreatment.com/treatment-options)

Even if the ACL isn’t surgically repaired or braced to heal, good muscle control can take over the job of stabilising the joint. I have seen this in young athletes who have a positive draw test, but no problems playing sport or skiing (yes: really). The catch is, and this applies to those undergoing surgery as well, exercises must be kept up. Once prone to knees collapsing painfully, chances are: it can happen again WHETHER OR NOT SURGERY IS UNDERTAKEN [14] and in the OTHER knee.

So, whatever the choice of treatment, do FULL rehab before returning to sport to minimise long term problems [15]. Once a good neuromuscular exercise routine is established, keep at it. On both knees. This should not be onerous. Know when muscles need time out: don’t be a court/field hog. Or reconsider your sport if it is too risky for you.

Choose helpful exercise, good match preparation and sensible play, not pain!

References

1. Fleming, J.D., R. Ritzmann, and C. Centner, Effect of an Anterior Cruciate Ligament Rupture on Knee Proprioception Within 2 Years After Conservative and Operative Treatment: A Systematic Review with Meta-Analysis. Sports Medicine, 2022. 52(5): p. 1091-1102.

2. Lien-Iversen, T., et al., Does surgery reduce knee osteoarthritis, meniscal injury and subsequent complications compared with non-surgery after ACL rupture with at least 10 years follow-up? A systematic review and meta-analysis. British Journal of Sports Medicine, 2020. 54(10): p. 592.

3. Webster, K.E. and T.E. Hewett, Anterior Cruciate Ligament Injury and Knee Osteoarthritis: An Umbrella Systematic Review and Meta-analysis. Clinical Journal of Sport Medicine, 2022. 32(2).

4. Barber-Westin, S. and F.R. Noyes, One in 5 Athletes Sustain Reinjury Upon Return to High-Risk Sports After ACL Reconstruction: A Systematic Review in 1239 Athletes Younger Than 20 Years. Sports Health, 2020. 12(6): p. 587-597.

5. Crawford, S.N., B.R. Waterman, and J.H. Lubowitz, Long-term failure of anterior cruciate ligament reconstruction. Arthroscopy, 2013. 29(9): p. 1566-71.

6. Bach, B.R., Jr., Revision anterior cruciate ligament surgery. Arthroscopy, 2003. 19(10): p. 14-29.

7. Frobell, R.B., et al., A randomized trial of treatment for acute anterior cruciate ligament tears. New England Journal of Medicine, 2010. 363(4): p. 331-342.

8. Frobell, R.B., et al., Treatment for acute anterior cruciate ligament tear: Five year outcome of randomised trial. BMJ (Online), 2013. 346(7895).

9. Harris, K.P., et al., Tibiofemoral Osteoarthritis After Surgical or Nonsurgical Treatment of Anterior Cruciate Ligament Rupture: A Systematic Review. Journal of Athletic Training, 2017. 52(6): p. 507-517.

10. Ekås, G.R., et al., 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. British Journal of Sports Medicine, 2020. 54(9): p. 520.

11. Filbay, S.R., et al., 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, 2023. 57(23): p. 1490.

12. Filbay, S.R., et al., Delaying ACL reconstruction and treating with exercise therapy alone may alter prognostic factors for 5-year outcome: an exploratory analysis of the KANON trial. British Journal of Sports Medicine, 2017. 51(22): p. 1622.

13. Saueressig, T., et al., Primary surgery versus primary rehabilitation for treating anterior cruciate ligament injuries: a living systematic review and meta-analysis. British Journal of Sports Medicine, 2022. 56(21): p. 1241.

14. Filbay, S.R., et al., Quality of life in anterior cruciate ligament-deficient individuals: a systematic review and meta-analysis. British Journal of Sports Medicine, 2015. 49(16): p. 1033.

15. Van Ginckel, A., P. Verdonk, and E. Witvrouw, Cartilage adaptation after anterior cruciate ligament injury and reconstruction: implications for clinical management and research? A systematic review of longitudinal MRI studies. Osteoarthritis and Cartilage, 2013. 21(8): p. 1009-1024.

Anne Brennan: pain research

ACL (cruciate) tears: surgery or not?

References

See also