Skip to content
Home » Blog » Should I Use a Knee Brace After ACL Surgery?

Should I Use a Knee Brace After ACL Surgery?

If you have ever played sports in a knee brace, you know that they can hinder your speed, power, and agility. They slow you down, but is it for good reason?

I posted a soccer-specific reactive cutting drill on my Instagram page not too long ago and got some interesting responses. The athlete in the video was about 8 months post-op and was not using a functional knee brace. We were in a controlled environment and I was dosing her activity accordingly, however, I seem to have struck a nerve for other rehabilitation specialists.

“No bracing for sport? There’s good research on the prophylactic benefits of return to sport bracing. The research advocates bracing, but I often see young PT’s encouraging athletes to avoid bracing because they ‘depend’ on braces. That’s not the case.”

Although the verbiage “prophylactic” and “return-to-sport” are literally direct contradictions, it made me search out “said” research.

Since that time, I’ve done some reviewing of the literature. I’ll attempt to summarize below…

This article will discuss rehabilitative (early post-operative) and functional (or return-to-sport) bracing. Rehabilitative bracing is used to allow early, but controlled motion of an injured limb. Think of your standard straight-leg brace or knee immobilizer immediately following surgery. Functional (or derotational bracing) is used to provide stability for patients with post-operative or ACL-deficient knees, but only after range of motion restrictions are lifted. These are the braces athletes use when returning back to sport from significant injury.

According to Marx et al., nearly 60% of doctors surveyed from the American Academy of Orthopaedic Surgeons (AAOS) recommended a brace for the first 6 weeks following ACL reconstruction, while approximately 63% of them recommended a brace for participation in sports postoperatively.2 Other research from the American Orthopaedic Society for Sports Medicine (AOSSM) shows even higher numbers, with bracing being used in approximately 85% of all cases following ACL reconstruction.3 Decoster and Vailas revealed that only 13% of surgeons “never” prescribe functional bracing to their ACL reconstruction patients, with only 3% of surgeons “never” bracing ACL-deficient patients.4

Macintosh HD:Users:juliehubbard:Desktop:Screen Shot 2019-10-30 at 2.54.24 PM.png

With current injury rates (~200,000 per year/US)5, it is reasonable to assume that more than 100,000 functional knee braces are prescribed in the United States every year. With the average functional knee brace costing approximately $592 USD, this puts a significant financial burden of nearly $59,200,000 on our healthcare system… every year.

So, are you ready to put your money where your mouth is? What does the research say?

Early Post-Operative Bracing

Early post-operative rehabilitative bracing is often performed following ACL-R to protect the graft, limit range of motion (while specifically preserving extension), protect against excessive varus-valgus forces, and prevent anterior-posterior translation and/or rotation of the tibia.

Interestingly enough, Di Miceli et al. showed that bracing and delayed weight bearing after ACL-R might actually have a negative effect on long-term functional outcomes according to IKDC score.6

Bordes et al. published similar findings when revealing no significant difference in clinical outcomes between 969 patients who were assigned to early-bracing or non-bracing groups.7

Rodriguez-Merchán et al. found similar findings, stating that there was no sufficient evidence to inform current practice of routine knee brace immediately following ACL reconstruction.8

All three of these research articles also support the idea that accelerated rehabilitation, early weight bearing, and early ROM are generally safe and beneficial to patient outcomes.

But not so fast! Before you unstrap yourself, continue reading…

Lowe et al. conducted a systematic review stating that early functional bracing may protect the implanted graft after ACL reconstruction without sacrificing function, range of motion, or proprioception.9

Other research by Fleming et al. showed that knee bracing could provide good protection against low-intensity anteroposterior displacement and subphysiological rotational movements.10 

Beynnon et al. has also provided us with the knowledge that bracing can reduce ACL strain in response to a maximum of 140 N anterior tibial force (weight-bearing and non-weight-bearing) and 8 Nm internal tibial torques (non-weight-bearing).12 The protective effects of bracing, however, are not observed with higher forces, weight-bearing tibial torques, isometric quadriceps contraction, or active flexion-extension.

With a mixed bag of sorts, I can see the validity in someone’s argument to immediately throw away their straight-leg brace or knee immobilizer upon leaving the hospital. Personally and professionally, however, if there is a way to possibly mitigate injury to that brand new graft for two to three weeks, I’m all for it.

Return-to-Sport Bracing

We know that bracing can protect the ACL graft from anterior tibial translation up to 140 N and rotational torque up to 8 Nm. Athletic events, however, are comprised of unanticipated bursts of powerful movements, far exceeding these subphysiological values.  So, is there any merit to functional knee bracing during athletics? Keep reading.

McDevitt et al. conducted a prospective RCT to assess the effectiveness of functional knee bracing after ACL-R. These researchers looked at 100 patients who were immediately placed in a straight-leg brace following ACL-R. After three weeks, both groups were discharged from the knee immobilizer. One group was then given a functional brace at the six-week mark and told to wear the brace with all activities up until 6 months post surgery, at which time the functional brace was to only be applied during higher-level activities up until one year post-op. The other group was given nothing. Both groups of patients were followed up with after two years, revealing no difference in knee stability, hop testing, range of motion, isokinetic strength, and International Knee Documentation Committee or Lysholm scores.13

Birmingham et al. conducted a similar randomized controlled trial where researchers assigned 150 patients 6-weeks post-op ACL-R to a functional knee brace or neoprene sleeve group. Patients were then followed up at one and two year marks, where there were no significant differences in compliance or outcome measure (as recorded with ACL-QOL, KT1000 arthrometer, single-limb hop test, and Tegner activity scale.14

Wright and Fetzer performed a systematic review of Level I evidence revealing no evidence that pain, range of motion, graft stability, or protection from subsequent injury were affected by functional brace use.15 Yang et al. concluded that no functional knee brace has been successfully validated as a means to reduce the risk of re-injury after ACL reconstruction, and that as such, bracing for patients treated with ACL-R should not be recommended routinely.17 Smith et al. concluded that biomechanical and clinical evidence suggests current functional bracing technologies do not sufficiently restore normal biomechanics to the ACL-deficient knee, protect the reconstructed ACL, and improve long- term patient outcomes.12 Pezzullo and Fadale concluded that the use of functional knee bracing to lower the risk of re-injury is not supported in the literature and that it is thus difficult to include as a component of the standard ACL rehabilitation protocol.16

There has been sufficient evidence, however, that functional knee bracing is effective in protecting the graft from re-injury in skiers. Various studies have shown that skiers who are either ACL-deficient or who have undergone ACL reconstruction are as much as six times more likely to sustain a knee injury when not wearing a brace.17 Injury rates for non-braced ACL-R skiers has been reported to be as high as 13%, while bracing can reduce this number to only 2%. Now, that’s some food for thought.

I’m not going to lie. I’ve not found any research definitively supporting the use of functional knee bracing to reduce risk of re-injury in ACL-R patients.

But, that does not mean that knee bracing is a bad thing!

In many of the above studies, levels of subjective confidence and psychological readiness were positively affected by brace use. Braces are great for reducing kinesiophobia, while also facilitating return to previous levels of confidence.

In my professional opinion, knee braces can be helpful during the return to sport process from the 9-12 month mark. Like a security blanket, though, we need to prepare athletes for the moment when they get to leave them on the sideline. I like to prepare my athletes for this moment in controlled environments, with appropriate dosing and monitoring of fatigue levels and biomechanics.

Thanks for reading along and until next time – be well!


  1. Yang, X., Feng, J., He, X., Wang, F. and Hu, Y. (2019). The effect of knee bracing on the knee function and stability following anterior cruciate ligament reconstruction: A systematic review and meta-analysis of randomized controlled trials. Orthopaedics & Traumatology: Surgery & Research, 105(6), pp.1107-1114.
  2. Marx RG, Jones EC, Angel M, Wickiewicz TL, Warren RF. Beliefs and attitudes of members of the American Academy of Orthopaedic Surgeons regarding the treatment of anterior cruciate ligament in- jury. Arthroscopy. 2003;19:762–770.
  3. Delay BS, Smolinski RJ, Wind WM, Bowman DS.Current practices and opinions in ACL reconstruction and rehabilitation: results of a survey of the American Orthopaedic Society for Sports Medicine. Am J Knee Surg 2001;14:85–91.
  4. Decoster LC, Vailas JC (2003) Functional anterior cruciate lig- ament bracing: a survey of current brace prescription patterns. Orthopedics 26(7):701–706
  5. Escamilla RF, Macleod TD, Wilk KE, Paulos L, Andrews JR (2012) Anterior cruciate ligament strain and tensile forces for weight-bearing and non-weight-bearing exercises: a guide to exercise selection. J Orthop Sports Phys Ther 42(3):208–220
  6. Di Miceli R, Marambio CB, Zati A, Monesi R, Benedetti MG. Do knee bracing and delayed weight bearing affect mid-term functional outcome after anterior cruciate ligament reconstruction? Joints 2017;5:202–6.
  7. Bordes P, Laboute E, Bertolotti A, et al. No beneficial effect of bracing after anterior cruciate ligament reconstruction in a cohort of 969 athletes followed in rehabilitation. Ann Phys Rehabil Med 2017;60:230–6.
  8. Rodríguez-Merchán EC. Knee bracing after anterior cruciate ligament recon- struction. Orthopedics 2016;39:e602–9.
  9. Lowe WR, Warth RJ, Davis EP, Bailey L. Functional bracing after anterior cruciate ligament reconstruction. J Am Acad Orthop Surg. 2017;25(3):239–249.
  10.  Fleming BC, Renstrom PA, Beynnon BD, Engstrom B, Peura G. The influence of functional knee bracing on the anterior cruciate ligament strain biome- chanics in weightbearing and nonweightbearing knees. Am J Sports Med 2000;28:815–24.
  11. Beynnon BD, Johnson RJ, Fleming BC, Peura GD, Renstrom PA, Nichols CE, Pope MH (1997) The effect of functional knee bracing on the anterior cruciate ligament in the weightbearing and nonweightbearing knee. Am J Sports Med 25(3):353–359
  12. Lowe WR, Warth RJ, Davis EP, Bailey L. Functional bracing after anterior cruciate ligament reconstruction. J Am Acad Orthop Surg. 2017;25(3):239–249.
  13. McDevitt E, Taylor D, Miller M, et al. Functional bracing after anterior cruciate ligament reconstruction. A prospective, randomized, multicenter study. Am J Sports Med. 2004;32: 1887–1892.
  14. Birmingham TB, Bryant DM, Litchfield RB, et al. A random- ized controlled trial comparing the effectiveness of functional knee brace and neoprene sleeve use after anterior cruciate ligament reconstruction. Am J Sports Med. 2008;36:648–655.
  15. Wright RW, Fetzer GB. Bracing after ACL Reconstruction—a systematic review. Clin Orthop Relat Res. 2007;455:162–168. doi: 10.1097/BLO.0b013e31802c9360.
  16. Pezzullo DJ, Fadale P.  Current controversies in rehabilitation after anterior cruciate ligament reconstruction. Sports Med Arthrosc.  2010; 18: 43– 47.
  17. Kocher MS, Sterett WI, Briggs KK, Zurakowski D, Steadman JR (2003) Effect of functional bracing on subsequent knee injury in ACL-deficient professional skiers. J Knee Surg 16(2):87–92.