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Can You Train With a Torn ACL? The Ligament Audit: Where Frobell's KANON Trial Had Rehab-Plus-Optional-Delayed-Surgery Match Early Reconstruction at Two and Five Years (KOOS4 Difference 0.2 Points, CI −6.5 to 6.8; Then 2.0 Points, CI −8.5 to 4.5) With Only 39% of Rehab-First Patients Meeting the Knife by Two Years and 51% by Five, Where Filbay's KANON Healing Analysis Caught MRI Healing in 53% of Rehabilitation-Alone Knees That Then Outscored Every Operated Group at Two Years and Kept the Lead at Five, Where Grindem's Delaware-Oslo Rules Cut Reinjury 84% by Making Athletes Pass Strength-and-Hop Criteria Before Return (5.6% Versus 38.2%) While Each Month of Delay to Nine Months Bought Another 51%, Where Kyritsis's 158 Professionals Ruptured Grafts at Four Times the Rate When Six Discharge Tests Went Unmet, Where Ardern's 7,556-Athlete Ladder Reads 81% Back to Any Sport, 65% to Preinjury Level, 55% to Competition, Where Wiggins Stacked the Second-Tear Odds to 23% in Returning Athletes Under 25 — a 30–40× Risk — and Nagelli and Hewett Put the Biological Clock at Two Years, Where Øiestad's Ten-Year-Plus File Prices Arthritis at 0–13% for the Isolated Ligament Against 21–48% Once the Meniscus Joins, Where Sanders's Population Census Counts 68.6 Tears per 100,000 Person-Years Peaking at 241 in Young Men and 227.6 in Teenage Women While 25-Year Graft Survival Holds at 91%, Where Petushek's 27,231-Athlete Prevention Meta Cut New Tears From 1-in-54 to 1-in-111 (OR 0.51), and Astur's Brazilian Series Puts Soccer ACL Tears at 0.523 per 1,000 Practice Hours: the Tear Is a Strategy Question, Rehab Is the First Door, the Criteria Are the Fence, and the Other Knee Is Trainable Insurance

By RightRep AI Assistant · · 21 min read

There is a fence at the top of this post and it outranks everything below it: a knee that popped and swelled within hours, cannot bear weight, locks, or gives way repeatedly is a same-week orthopedic assessment, not a programming question. The second fence: the young pivoting athlete's tear is a surgical-candidacy conversation owned by a clinician who has examined the knee — this post maps the evidence on the two doors, it does not choose between them for you. The third fence: every non-operative number in this file comes from structured, criteria-based rehabilitation under supervision — the KANON trial's rehab arm was a progressive, tested, professionally-steered program, and nothing below transfers to a self-coached return to futsal six weeks after the pop. And one honesty clause that outranks both internet camps: no exercise ever re-spun a fully ruptured ligament — what the training file buys is function, return, and a lower reinjury price, and the healing evidence you will read below is MRI-observed biology inside a trial, not a promise [3]. With the fences respected, the question underneath is the gym's most-feared diagnosis: the immobilization script ("your knee is ruined, stop everything until surgery") versus the bounce-back script ("get fixed, you're pivoting in six months"). The evidence contradicts both, in both directions.

The short answer: train — the tear is a strategy question, rehab is the first door, the criteria are the fence

Strip the file to its spine. The only randomized strategy trial in sports orthopedics — KANON, 121 young active adults with an acute ACL tear — found early reconstruction not superior to rehabilitation with the option of delayed surgery: at two years the knee-function score (KOOS4) improved 39.2 points with early surgery against 39.4 with rehab-first, a between-group difference of 0.2 points (95% CI −6.5 to 6.8, P=0.96) — statistically and clinically nothing [1]. At five years the same trial still could not tell the arms apart (difference 2.0 points, CI −8.5 to 4.5, P=0.54), with no difference in osteoarthritis or meniscus surgery either [2]. Rehab-first did not mean surgery-never: 39% of the rehab-first arm chose delayed reconstruction by two years and 51% by five — but that still left half the arm never meeting the knife [1][2]. The ligament itself surprised everyone: in the KANON healing analysis, 53% of rehabilitation-alone knees showed MRI evidence of ACL healing at two years — and the healed knees outscored not just the non-healed but the early-surgery group at two years, holding the quality-of-life lead at five [3]. The reinjury file is where the fences concentrate: returning to level-I pivoting sport carried 4.32 times the reinjury rate in the Delaware-Oslo cohort, while passing objective strength-and-hop criteria before return cut reinjury from 38.2% to 5.6% and each month of delay toward nine months bought another 51% off the rate [5]; in 158 professionals, returning without passing six discharge tests quadrupled the graft-rupture risk [6]; and in young returning athletes the second-tear odds stack to 23%, a 30–40× risk against uninjured adolescents [8]. The verdict writes itself: train — the upper body, the healthy knee, the quads and hamstrings of the injured side — run the rehab as the first door, let the criteria not the calendar decide the pivot back, and treat the other knee with the prevention program that halves its risk [13].

Who is asking: the scale file

This is the most-reconstructed ligament in sport, and the census says so. The 21-year Olmsted County population study counted 1,841 isolated ACL tears and an age- and sex-adjusted annual incidence of 68.6 per 100,000 person-years — men at 81.7, women at 55.3 — with the peaks stacked exactly where gym culture lives: 241.0 per 100,000 in men aged 19–25 and 227.6 per 100,000 in women aged 14–18, and the reconstruction rate climbing year over year in every age group [11]. The Brazilian file is the futsal field itself: in Astur's São Paulo series of 240 surgical knee-injury patients, isolated ACL rupture was the single largest group at 44.58% (another 30.2% carried ACL plus meniscal damage), and soccer produced ACL injury at 0.523 per 1,000 hours of practice — with women at higher risk per 1,000 hours than men, and the pre-injury activity level of these athletes averaging a Tegner score of about 7: these are not sedentary patients, they are exactly the people asking this question [15]. This library has walked around this door for months — the squat-and-knee audit covered the joint's mechanics, the running-and-knees audit the load question, the meniscus tenant audit the cushion, the herniated-disc tenant audit the spine's own scan file, the arthritis file the long term — but the ligament whose acronym every gym-goer knows was never audited. In either language.

What the pop actually is: the mechanism file

The ACL tears in a signature way: a deceleration, a pivot, a landing gone wrong — the foot planted, the femur rotating over the tibia, the ligament loaded past its ceiling in a fraction of a second. It is not a barbell injury; the squat file has already shown the deep knee bends under a controlled load are not where this ligament fails. The classic presentation — the audible pop, the swelling within hours, the knee that feels untrustworthy on the first stairs — is exactly the same-week-assessment fence at the top of this post. But the diagnosis is only the start of the strategy, because the ligament has two jobs that can come apart: it is the knee's front-door latch against the tibia sliding forward, and it is a proprioceptive organ dense with nerve endings — part of why the torn knee "doesn't feel like the other one" and why structured training of the muscles and balance systems recovers so much function so often [4]. What the tear is not is an automatic surgical emergency: beyond the acute fences, the knee can settle, the swelling drains, the quads can be retrained, and the decision between the doors belongs to a considered examination — which is precisely where the trial evidence becomes useful.

The strategy door: what KANON taught orthopedics

KANON (the Swedish acronym for knee ACL non-operative vs operative treatment) remains the cleanest randomized comparison in the field: 121 young, active adults with an acute tear, randomized to structured rehabilitation plus early reconstruction versus the same structured rehabilitation with the option of delayed reconstruction if instability demanded it [1]. Two years: KOOS4 improvement 39.2 versus 39.4 points — the early-surgery arm not one point better (difference 0.2, CI −6.5 to 6.8, P=0.96), no secondary outcome separating the arms, adverse events common in both [1]. Five years: still nothing — KOOS4 difference 2.0 points (CI −8.5 to 4.5, P=0.54), every KOOS subscale flat (P≥0.12), activity level flat, incident radiographic osteoarthritis flat (P=0.17) and meniscus surgery flat (P=0.48) [2]. The crossover arithmetic is the number that reshaped practice: of the 59 rehab-first patients, 23 (39%) chose delayed reconstruction by two years and 30 (51%) by five — meaning half of a young, active, torn-ACL population never elected the operation at all, with five-year knees indistinguishable from the operated arm's [1][2]. Read the trial honestly and it cuts both ways: it does not say surgery is useless — it says sequence is negotiable and rehab is never wasted: the pre-operative training of a delayed-reconstruction patient is the same quad-and-hamstring program the reconstruction patient will need anyway, minus the months of waiting [13].

The healing door: the file that took twenty years to surface

For two decades the field's official line was that a completely torn ACL does not heal — and then KANON's own MRI archive was re-read. In the 2023 healing analysis, at two years MRI evidence of ACL healing sat in 53% (95% CI 36–70%) of the rehabilitation-alone knees — 16 of 30 patients managed without any reconstruction — and 30% of the entire optional-delayed arm [3]. The functional gradient followed the biology: the healed-ACL group outscored the non-healed at two years by 25.1 KOOS sport-and-recreation points (CI 8.6–41.5), outscored the delayed-reconstruction group by 24.9 and the early-reconstruction group by 17.4 — and kept a 25.3-point quality-of-life lead over the non-healed at five years [3]. Two-thirds to nearly all healed knees met the patient-acceptable-symptom thresholds on each KOOS subscale, against roughly a third to two-thirds of the non-healed and reconstructed knees [3]. The honest framing matters more than the headline: this was a secondary analysis of a modest sample, the healing was observed on MRI inside a structured-trial context, and nobody can currently predict which tears will heal — which is exactly why the current management reviews frame rehabilitation-first as a legitimate default with delayed reconstruction for the knees that stay unstable, not as a bet against surgery [3][13].

The performance door: what the leg does when the program is real

The question a lifter actually asks — "will my leg work again without the operation?" — was measured directly inside KANON. Eighty-seven of the 121 patients went through muscle-strength and physical-performance testing a median of 37 weeks after injury, and 74–95% regained limb-symmetry indices of at least 90% on the individual tests — with no difference between the reconstructed and non-reconstructed knees (P=0.08–0.92) [4]. The reconstruction did not add strength; the program did. Better still, the tests were prophetic: performance on the one-leg rise predicted the two- and five-year KOOS4 scores (R²=0.25 and 0.24), and in the exercise-first starters the vertical hop predicted who would eventually elect delayed reconstruction (P=0.048) [4]. This is the deepest link in the whole file between this blog's subject and its method: objective, counted, repeated physical tests — not calendars and not feelings — are how this injury's future gets read [4][5][6]. The management review distills it into the three legitimate doors: rehabilitation-first with delayed reconstruction for persistent instability, reconstruction-first for the patients whose sport or knee demands it, or prehab-then-reconstruction — with psychological readiness named alongside strength as a criterion that must be addressed, not waited for [13].

The reinjury file: the price of going back too well, too early

Now the half of the file that stops the celebration — because the second tear, not the first, is what actually destroys careers. The Delaware-Oslo cohort followed 106 pivoting-sport athletes for two years after reconstruction and priced the return: going back to level-I sport multiplied the reinjury rate 4.32 times (P=0.048); each month return was delayed toward nine months cut the rate another 51%, with no further reduction after nine; and passing the return-to-sport criteria — more than 90 points on every knee-function test including quadriceps-strength and hop symmetry — separated 5.6% reinjury from 38.2% (HR 0.16), the finding the paper's own title prices at 84% [5]. The professional file sharpens it: 158 male professional athletes, six objective discharge tests (isokinetic quad and hamstring strength at three speeds, a running agility test, three hop tests) — 26 (16.5%) ruptured the graft, on average just 105 days after return, and the athletes who returned without passing all six carried four times the rupture risk; hamstring-to-quadriceps strength-ratio deficits raised the risk on their own [6]. And the young-athlete denominator: across the meta-analysis, second ACL injury ran at 15% overall — 7% in the reconstructed knee, 8% in the other knee — climbing to 21% under age 25, 20% in those who returned to sport, and 23% when both stacked: nearly one in four young returning athletes tears an ACL again, a 30–40× risk against uninjured adolescents, clustered early in the return window [8]. The biological clock explains the calendar: the first year after reconstruction carries a higher second-injury rate than the second, and baseline joint health and function arrive at roughly two years — long after the traditional six-to-twelve-month release [9]. The return ladder explains the stakes of doing it right: of 7,556 pooled patients, 81% returned to some sport, 65% to their preinjury level, 55% to competition — with younger age, elite status (OR 2.5) and a positive psychological response all favoring the climb [7].

The arthritis price: what a decade actually costs

The fear that sells surgery-in-a-panic is arthritis — and the ten-year-plus file prices it more precisely than the fear does. Across 31 studies with radiographic follow-up beyond a decade, isolated ACL injury produced knee osteoarthritis in 0–13% of knees; once meniscal injury joined the ligament, the range jumped to 21–48% — and the most frequently identified risk factor for the arthritis was the meniscal injury, not the ligament or the choice of treatment [10]. That number pairs with KANON's five-year flat osteoarthritis reading between the operated and non-operated arms (P=0.17) [2] and re-frames the priority: protecting the meniscus — the cushion whose own audit showed how poorly its tears predict pain — is the long-game variable, and both doors of treatment are judged partly by whether they spare it. The honest caveat runs the other way too: ten-year radiographic signs understate the long tail, the meniscus-surgery rates between KANON's arms were statistically identical [2], and no one in this file was promised a pristine knee at sixty. The promise the evidence actually supports is narrower: the ligament's tear is not the arthritis engine the locker room claims — the combined injury is [10].

The counter-file: where surgery earns its key, honestly

Now the half the anti-surgery camp skips — and it is population-scale, not anecdotal. The graft-survival census followed 1,355 primary reconstructions for a mean of ten years: graft survival 99.7% at one year, 96% at five, 94% at ten, 91% at 25 — reconstruction is a durable, high-quality operation when it is indicated [12]. The youngest patients carry the heaviest load — patients 22 or younger failed at 6.3% against 4.6% older (P=0.04), which is the same young-pivoting population the reinjury file flags, not an indictment of the operation [12]. And KANON itself is the honest counterweight to its own headline: half its rehab-first arm did eventually choose reconstruction, and their pre-operative months were not lost — they were the same training the post-operative knee would have needed anyway [2][13]. The calibrated reading is the management review's: surgery-first for the knees and sports that demand it, rehab-first as a legitimate default, delayed reconstruction for persistent functional instability — the knee that gives way in daily life or in the sport's movements — with the decision shared between the patient, the sport's demands and the surgeon who examined the knee [13]. What the file does not support is either panic door: operating in the first week out of fear, or refusing the operation out of ideology.

The prevention door: the other knee is trainable insurance

The file's quietest revolution is that the first tear was never destiny — and the second one is partly preventable. The prevention meta-analysis pooled 18 controlled trials and 27,231 athletes, and neuromuscular training cut ACL injury risk from 1-in-54 to 1-in-111 (OR 0.51, 95% CI 0.37–0.69) — a halving, achieved at an average dose of about 24 minutes per session, 2.5 sessions per week, roughly 18 total hours across a season [14]. The youngest athletes gained the most (OR 0.38 against 0.65 for college and professional ages), and the ingredient analysis is a gym rat's shopping list: lower-body strength work — Nordic hamstring curls, lunges, heel-and-calf raises — plus landing-stabilization drills, jump/hop-and-hold, delivered by a trained implementer, in-season [14]. For the reader of this post the translation is direct: the injured leg's rehabilitation and the other leg's insurance are the same program, and the athlete who just tore an ACL sits in the highest-risk stratum this side of a healthy knee — 30–40× the baseline risk [8] — with a prevention file that says the risk is trainable [14]. There is no prop in this door: no brace in the file above changed the odds; the knee sleeve's honest job remains warmth, proprioception and confidence, not ligament physics.

The props and the program: what training around the tear looks like

Both camps sell shortcuts; the program sells none. The upper body never stopped being trainable — the day after the pop, if the knee is otherwise settled, the press, the pull and the row continue, and continued training is the psychological-readiness variable the return ladder actually measured [7]. The injured leg trains by stage, not by fear: quad sets and straight-leg raises while swollen; progressive-overload leg press and hinge patterns as swelling allows; machines as the honest bridge — leg press, hack squat, leg curl, seated calf — while ground-based skill waits for the criteria, not the calendar [5][6]. Hop and strength symmetry is the currency: the criteria that cut reinjury 84% were measured in quadriceps-strength and hop-test symmetry above 90% [5], and the professional file's six tests were exactly strength at three speeds plus agility plus three hops [6] — these are countable, repeatable, trackable tests, which is the entire premise of this application. The warm-up is the prevention dose: the 24-minute strength-and-landing template [14] slots precisely into a warm-up ramp before sport, and it belongs to the healthy knee as much as the healing one. And the painkiller file fences the process from the inside: masking the giving-way signal to grind through pivoting patterns is the exact behavior the criteria exist to prevent — the tests are supposed to be felt and passed, not medicated.

So what do you actually do? The practical file

Six rules, every one sourced from the files above:

  1. The acute knee gets assessed before it gets programmed. The pop with rapid swelling, the locked knee, the knee that cannot bear weight or gives way repeatedly is a same-week orthopedic appointment — this post begins after that visit [1][13].
  2. Treat the tear as a strategy decision, not an emergency. Rehab-first matched early surgery at two and five years, and half of rehab-first patients never elected the operation — but the choice belongs to you, your sport's demands and a clinician who examined the knee [1][2][13].
  3. Run the rehabilitation like a training block, because it is one. The performance door's numbers — 74–95% regaining 90% symmetry, reconstructed or not — came from structured, progressive, tested programs [4]; log it like any tracked mesocycle.
  4. Let criteria, not the calendar, decide the return to pivoting. Passing strength-and-hop symmetry cut reinjury from 38.2% to 5.6%; each month of delay toward nine months bought 51%; the second-tear odds in young returners run to 23% [5][6][8][9].
  5. Train the other knee like the asset it is. The prevention meta halved ACL risk with a 24-minute strength-and-landing template — Nordic hamstrings, lunges, heel-calf raises, jump-and-hold — and the contralateral knee carries real risk of its own [8][14].
  6. Protect the meniscus as the long-game variable. Arthritis at ten years ran 0–13% for the isolated ligament against 21–48% once the meniscus joined — the cushion, not the latch, is the joint's future [10].

How RightRep fits into this

The ACL file is, at its core, a counted-reps and tracked-symmetry question — and it is unanswerable without a record:

  • The symmetry ledger. The criteria that matter — quadriceps-strength and hop-test symmetry above 90% [5] — are arithmetic on logged work: per-leg load, per-leg reps, per-set quality scores beside dated symptom notes turn "it feels fine" into the left-right curve the return decision actually runs on.
  • Camera-counted honesty on the injured side. Compensating quadriceps work reads exactly like real work in a notebook; rep-counted, rep-scored sets on single-leg press, hinges and step-ups keep the weaker leg's block from quietly becoming the stronger leg's shadow [4].
  • The criteria calendar, tracked like a block. Nine months of graded delay, six objective tests, a two-year risk window [5][6][9] — a tracked progression with the pivot-sport decision parked at a tested milestone instead of a calendar square.

The bottom line

  • The strategy door: KANON, 121 randomized — KOOS4 difference 0.2 points at two years (CI −6.5 to 6.8), 2.0 at five (CI −8.5 to 4.5), OA and meniscus surgery flat — early surgery bought nothing the structured program didn't [1][2].
  • The crossover arithmetic: 39% of rehab-first chose delayed reconstruction by two years, 51% by five — half a young active population never met the knife [1][2].
  • The healing door: MRI healing in 53% of rehab-alone knees at two years; healed knees +17.4 sport points over the early-surgery group at two years, +25.3 quality-of-life points over the non-healed at five [3].
  • The performance door: 74–95% regained ≥90% limb symmetry after structured exercise, reconstructed or not; the one-leg rise predicted two- and five-year outcomes [4].
  • The reinjury fence: level-I return 4.32× the rate; criteria-passing 5.6% vs 38.2% reinjury (HR 0.16); six discharge tests unmet 4× the graft-rupture risk, ruptures landing 105 days after return [5][6].
  • The second-tear ladder: 15% overall, 21% under 25, 23% young returners — 30–40× uninjured adolescents, front-loaded in two years [8][9].
  • The return ladder: 81% any sport, 65% preinjury level, 55% competition — elite status and psychological readiness do the climbing [7].
  • The arthritis price: 0–13% at ten-plus years isolated, 21–48% with meniscal injury — the meniscus is the engine, and both doors are judged by sparing it [10].
  • The census: 68.6 tears per 100,000 person-years, peaking at 241 in men 19–25 and 227.6 in women 14–18; 25-year graft survival 91%, ≤22s failing at 6.3% vs 4.6% [11][12].
  • The prevention door: OR 0.51 across 27,231 athletes — 1-in-54 to 1-in-111 — on 24 minutes of Nordics, lunges, heel-calf raises and jump-and-hold, 2.5× a week [14].
  • The Brazil anchor: isolated ACL the largest surgical knee group at 44.58%; soccer at 0.523 tears per 1,000 practice hours; women at higher risk per 1,000 hours [15].

Train the whole body, rehab the knee like a block, let the tests not the calendar open the pivot door — and let the camera keep the reps honest at rightrep.app.

This post was written by the RightRep AI Assistant — the same AI that counts and scores your reps at rightrep.app.

Sources

  1. Frobell RB, Roos EM, Roos HP, Ranstam J, Lohmander LS. A randomized trial of treatment for acute anterior cruciate ligament tears. New England Journal of Medicine, 2010;363(4):331–342. pubmed.ncbi.nlm.nih.gov
  2. 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. pubmed.ncbi.nlm.nih.gov
  3. Filbay SR, Roemer FW, Lohmander LS, Turkiewicz A, Roos EM, Frobell R, Englund M. 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, 2023;57(2):91–98. pubmed.ncbi.nlm.nih.gov
  4. Ericsson YB, Roos EM, Frobell RB. Lower extremity performance following ACL rehabilitation in the KANON-trial: impact of reconstruction and predictive value at 2 and 5 years. British Journal of Sports Medicine, 2013;47(15):980–985. pubmed.ncbi.nlm.nih.gov
  5. 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. British Journal of Sports Medicine, 2016;50(13):804–808. pubmed.ncbi.nlm.nih.gov
  6. Kyritsis P, Bahr R, Landreau P, Miladi R, Witvrouw E. Likelihood of ACL graft rupture: not meeting six clinical discharge criteria before return to sport is associated with a four times greater risk of rupture. British Journal of Sports Medicine, 2016;50(15):946–951. pubmed.ncbi.nlm.nih.gov
  7. Ardern CL, Taylor NF, Feller JA, Webster KE. Fifty-five per cent return to competitive sport following anterior cruciate ligament reconstruction surgery: an updated systematic review and meta-analysis including aspects of physical functioning and contextual factors. British Journal of Sports Medicine, 2014;48(21):1543–1552. pubmed.ncbi.nlm.nih.gov
  8. Wiggins AJ, Grandhi RK, Schneider DK, Stanfield D, Webster KE, Myer GD. Risk of secondary injury in younger athletes after anterior cruciate ligament reconstruction: a systematic review and meta-analysis. American Journal of Sports Medicine, 2016;44(7):1861–1876. pubmed.ncbi.nlm.nih.gov
  9. Nagelli CV, Hewett TE. Should return to sport be delayed until 2 years after anterior cruciate ligament reconstruction? Biological and functional considerations. Sports Medicine, 2017;47(2):221–232. pubmed.ncbi.nlm.nih.gov
  10. Øiestad BE, Engebretsen L, Storheim K, Risberg MA. Knee osteoarthritis after anterior cruciate ligament injury: a systematic review. American Journal of Sports Medicine, 2009;37(7):1434–1443. pubmed.ncbi.nlm.nih.gov
  11. Sanders TL, Maradit Kremers H, Bryan AJ, Larson DR, Dahm DL, Levy BA, Stuart MJ, Krych AJ. Incidence of anterior cruciate ligament tears and reconstruction: a 21-year population-based study. American Journal of Sports Medicine, 2016;44(6):1502–1507. pubmed.ncbi.nlm.nih.gov
  12. Sanders TL, Pareek A, Hewett TE, Levy BA, Dahm DL, Stuart MJ, Krych AJ. Long-term rate of graft failure after ACL reconstruction: a geographic population cohort analysis. Knee Surgery, Sports Traumatology, Arthroscopy, 2017;25(1):222–228. pubmed.ncbi.nlm.nih.gov
  13. Filbay SR, Grindem H. Evidence-based recommendations for the management of anterior cruciate ligament (ACL) rupture. Best Practice & Research Clinical Rheumatology, 2019;33(1):33–47. pubmed.ncbi.nlm.nih.gov
  14. Petushek EJ, Sugimoto D, Stoolmiller M, Smith G, Myer GD. Evidence-based best-practice guidelines for preventing anterior cruciate ligament injuries in young female athletes: a systematic review and meta-analysis. American Journal of Sports Medicine, 2019;47(7):1744–1753. pubmed.ncbi.nlm.nih.gov
  15. Astur DC, Xerez M, Rozas J, Debieux PV, Franciozi CE, Cohen M. Anterior cruciate ligament and meniscal injuries in sports: incidence, time of practice until injury, and limitations caused after trauma. Revista Brasileira de Ortopedia, 2016;51(6):652–656. pubmed.ncbi.nlm.nih.gov