Which ACL injuries suit repair rather than replacement?

Written by Dr Sean Leo, a consultant orthopaedic surgeon whose clinical focus is the knee, sports injuries and the lower limb.

Last updated: 9 October 2026.

Only a selected group of ACL tears can be repaired. The best-known approach, proximal repair, is considered for acute tears near the ligament’s upper attachment, with tissue that is still in good enough condition to be reattached. Repair is not an option for every tear, and when surgery is needed, current guidance favours reconstruction ^[2].

Which ACL tears can be repaired?

Only a selected group of ACL tears can be repaired. The best-known approach, proximal repair, is considered for acute tears near the ligament’s upper attachment, with tissue that is still in good enough condition to be reattached. A different technique, bridge-enhanced repair (BEAR), has been tested in patients with a complete tear in the middle of the ligament ^[3] (see is ACL repair viable). Repair is not an option for every tear, and when surgery is needed, current guidance favours reconstruction ^[2].

• Repair reattaches the torn ligament to the bone, using sutures and anchors. It is considered for selected acute tears, typically Sherman type I or II patterns (tears at or very near the ligament’s upper attachment).
• The tissue also has to be of adequate quality.
• Reconstruction replaces the torn ligament with a graft. It is the approach the 2022 American Academy of Orthopaedic Surgeons (AAOS) guideline recommends, in preference to repair, when surgery is indicated ^[2].

More on how repair is done

A repair is sometimes protected with a strip of suture tape, called suture-tape augmentation. The aim is to support the repair.

What does this page cover?

• Which ACL tears can be repaired?
• Is repair an option for every tear?
• What about healing without surgery?
• What decides whether repair is suitable?
• When should a knee injury be checked urgently?
• What should I discuss at a consultation?

Is repair an option for every tear?

No. Repair is a selective option. The evidence on how well it lasts is still limited, and it can fail.

• Repair can fail, and the knee may then need reconstruction ^[3,4].
• The 2022 AAOS guideline recommends reconstruction rather than repair when surgical treatment of an ACL tear is indicated, citing a lower risk of revision ^[2].
• Repair is not yet universally accepted as a standard alternative to reconstruction.

More on what the studies show

For suture-augmented repair of proximal tears, a 2022 systematic review (a structured summary of earlier studies; Vermeijden et al.) found no randomised studies, an average follow-up of about two years and a weak grade of recommendation ^[4]. The failure rate may have been higher in younger patients, although the estimate was very imprecise ^[4]. Newer comparisons still involve knees chosen by tear location and tissue quality, which is why the results do not apply to every ACL tear.

What about healing without surgery?

Some ACL tears may show signs of healing, but this evidence is early and uncertain ^[5]. It does not mean a torn ACL can be relied on to heal by itself.

• One approach, the Cross Bracing Protocol, was developed to bring the torn ends of the ACL closer together during early healing. It is a brace protocol, not a cast.
• The original study (Filbay et al., 2023) was a case series of 80 consecutive patients with no comparison group ^[5]. An MRI scan showed evidence of ACL healing at three months in 72 of 80 participants (90%) ^[5]. That is not the same as normal ligament structure, stable function, return to sport or freedom from reinjury, and 11 participants (14%) re-injured their ACL, on average about 10 months later (range 5 to 18 months) ^[5].
• The evidence so far is limited and conflicting. A randomised comparison is registered, so definitive comparative conclusions are not yet available ^[7].

More on the demands of this approach

The protocol asks a great deal of the person undertaking it. Its risks and inconveniences are not trivial: weeks with the knee held in a brace, crutches in the early weeks, and possible disruption to work and daily life. The original report also recorded deep-vein thrombosis (DVT, a blood clot in a leg vein) in two patients, which led the treating group to add preventive measures ^[5]. It should be supervised by appropriately trained clinicians and physiotherapists and should not be copied from a webpage.

A later controlled cohort study (Porter and Shadbolt, 2026) of 80 active people aged 16 to 40 who intended to return to pivoting sport compared Cross Bracing with surgical stabilisation at two years ^[6]. Recurrent instability was recorded in 70% of the Cross Bracing group (40 people) and 2.5% of the surgical group (40 people), and a medial meniscal tear (a tear of the cartilage cushion on the inner side of the knee) in 62% and 2.5% ^[6]. Because people chose their treatment rather than being randomly assigned, and all the patients came from one private practice, the comparison may reflect who chose each option ^[6].

What decides whether repair is suitable?

A treating surgeon weighs several things together: where the tear is, the quality of the ligament tissue, how recently the injury happened, the person’s age, their activity and any other injuries in the knee. No single feature decides on its own.

• Tear location and tissue quality matter for repair, because only selected acute tears near the top attachment are considered.
• Timing matters, because repair is considered for acute tears.
• Age, activity and associated injuries, such as a meniscal tear, all shape the options.
• Age, the sport you play, an MRI appearance or a report of a “complete tear” does not decide treatment on its own.

More on how imaging fits in

MRI adds information to the history and examination, especially when early guarding limits what can be tested. MRI does not decide treatment by itself. It is read together with your story and the examination.

When should a knee injury be checked urgently?

What should I discuss at a consultation?

If you have been told you have an ACL tear and want to know whether repair could apply to you, an assessment is the place to find out. It brings together what happened, an examination, and any imaging that helps, so that you and your clinician can decide what to do next. An appointment supports an informed decision. It is not a commitment to surgery.

• Ask where your tear is and what the tissue looks like on the scan.
• Ask how long ago the injury happened, and whether that matters for your options.
• Ask whether reconstruction, rehabilitation alone or another approach fits your goals better.
• When you see a clinician, mention which sport or work you want to return to. For high-risk pivoting sport after reconstruction, return is commonly around nine months or longer, an orientation rather than a clearance date ^[8,9]. Timelines after repair are individual and are best discussed with your surgeon.
• Some people regain useful function with structured rehabilitation and changes to activity, while others continue to have giving way or need stability for work or sport involving cutting and pivoting.

• Read how an ACL injury is assessed, and how repair, reconstruction and rehabilitation compare, on the ACL reconstruction surgery page.
• Browse the Knee Hub for other knee problems.
• Read about how ACL repair differs from reconstruction.
• Read about whether a torn ACL can heal without surgery.
• Read about tips for recovering after ACL surgery.

References

1. American Academy of Orthopaedic Surgeons. Management of Anterior Cruciate Ligament Injuries: Evidence-Based Clinical Practice Guideline. Rosemont (IL): AAOS; published 22 August 2022 (replacing the 2014 edition). Available from: https://www.aaos.org/aclcpg
2. Brophy RH, Lowry KJ. American Academy of Orthopaedic Surgeons Clinical Practice Guideline Summary: Management of Anterior Cruciate Ligament Injuries. J Am Acad Orthop Surg. 2023;31(11):531-537. doi:10.5435/JAAOS-D-22-01020. PMID:36727995. PMCID:PMC10168113.
3. Murray MM, Fleming BC, Badger GJ; BEAR Trial Team. Bridge-Enhanced Anterior Cruciate Ligament Repair Is Not Inferior to Autograft Anterior Cruciate Ligament Reconstruction at 2 Years: Results of a Prospective Randomized Clinical Trial. Am J Sports Med. 2020;48(6):1305-1315. doi:10.1177/0363546520913532. PMID:32298131. PMCID:PMC7227128. Trial registration: NCT02664545.
4. Vermeijden HD, van der List JP, Benner JL, Rademakers MV, Kerkhoffs GMMJ, DiFelice GS. Primary repair with suture augmentation for proximal anterior cruciate ligament tears: A systematic review with meta-analysis. Knee. 2022;38:19-29. doi:10.1016/j.knee.2022.07.001. PMID:35870397.
5. Filbay SR, Dowsett M, Chaker Jomaa M, Rooney J, Sabharwal R, Lucas P, 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. PMID:37316199. PMCID:PMC10715498.
6. Porter MD, Shadbolt B. Cross Bracing Protocol for Anterior Cruciate Ligament (ACL) Rupture Has Unacceptably High Failure Rate Relative to Surgical Stabilization: A 2-year Controlled Cohort Study. Clin J Sport Med. 2026;36(4):444-450. doi:10.1097/JSM.0000000000001416. PMID:41622530.
7. ClinicalTrials.gov. Cross Bracing Protocol Versus Surgery for Acute Anterior Cruciate Ligament Rupture. Identifier NCT06956339 (recruiting; record checked 5 October 2026). Available from: https://clinicaltrials.gov/study/NCT06956339
8. Grindem H, Snyder-Mackler L, Moksnes H, Engebretsen L, Risberg MA. Simple decision rules can reduce reinjury risk by 84% after ACL reconstruction: the Delaware-Oslo ACL cohort study. Br J Sports Med. 2016;50(13):804-808. doi:10.1136/bjsports-2016-096031. PMID:27162233. PMCID:PMC4912389.
9. Meredith SJ, Rauer T, Chmielewski TL, Fink C, Diermeier T, Rothrauff BB, et al. Return to sport after anterior cruciate ligament injury: Panther Symposium ACL Injury Return to Sport Consensus Group. J ISAKOS. 2021;6(3):138-146. doi:10.1136/jisakos-2020-000495. PMID:34006577.