When an ACL Graft Fails: Re-Rupture Causes and How Revision ACL Reconstruction Differs

Eight months after surgery, the knee finally felt like hers again. She had done the brace, the bike, the endless single-leg squats. Then, in the second half of a pickup game, she planted to cut left and heard the sound she had promised herself she would never hear twice. A dull pop. A knee that buckled. A long walk to the sideline with a very familiar dread.

This is the moment that brings people to the phrase acl graft failure, usually typed into a phone at midnight. The first surgery was supposed to be the end of the story. Instead there is a new set of questions: What went wrong? Was it something I did? Does a second operation even work the same way?

The honest answers are more reassuring than the midnight version, but they are also more detailed. A revision is not simply a repeat. Understanding why grafts fail, and what a surgeon has to think about the second time, is the best preparation for the conversations ahead.

What acl graft failure actually means

The anterior cruciate ligament, or ACL, is the short, strong band in the center of the knee that stops the shin bone from sliding forward and rotating too far under the thigh bone. When it tears, surgeons usually rebuild it with a graft: a piece of tendon taken from the patient’s own body or from a donor, threaded through drilled tunnels in the bone and fixed at each end. Over months, that tendon slowly remodels into tissue that behaves like a ligament (Johns Hopkins Medicine).

Graft failure is the term used when that new ligament no longer does its job. Sometimes it has torn completely, often with a memorable injury. Sometimes it has stretched or loosened gradually, so the knee feels less trustworthy without a single dramatic moment. Surgeons also count a graft as failed when the knee stays or becomes unstable on examination and imaging, even if the patient has adapted and stopped noticing day to day.

Two things are worth separating early. A painful knee after ACL surgery is not the same as a failed graft. Stiffness, scar tissue, kneecap pain and irritation from fixation hardware are all common reasons for a knee to hurt while the graft itself remains intact and tight. Conversely, a graft can be loose without much pain at all; the main complaint is often a sense of giving way when turning or stepping off a curb.

Most reconstructed knees hold up. Mayo Clinic describes ACL reconstruction as a reliable operation, while noting that reinjury is possible, particularly when someone returns to demanding sport too early. Failure is the exception, not the rule, but when it happens it changes the surgical problem in ways the next sections explain.

Why do ACL grafts fail? Traffic, technique and tissue

Surgeons who study revision cases tend to sort causes into three buckets, and most failed knees have more than one contributor.

The first bucket is traffic: a new injury. Cutting, landing from a jump, a tackle from the side, or a ski binding that does not release can overload any ligament, native or reconstructed. In the years after a first surgery, the operated knee faces the same forces that tore the original ACL, often in the same sport, sometimes before the graft has fully matured (Mayo Clinic).

The second bucket is technique. A graft is only as good as where it sits and how it is held. If a bone tunnel is drilled a few millimeters from the ligament’s natural footprint, the graft may be lax in some positions and overtightened in others, stretching a little with every step. Fixation that slips, a graft that was too small for the patient’s size, or a knee that was never quite stable after the first operation all belong here.

The third bucket is tissue. Healing is biological, and biology varies. Grafts go through a fragile phase while blood vessels grow in and cells remodel the tendon. A patient who is very young, has naturally loose ligaments, or returns to pivoting sport during that phase asks more of the graft than it can yet give. Donor grafts, which the body must repopulate with its own cells, appear to mature more slowly than tissue taken from the patient (Cleveland Clinic).

Missed companion injuries sit across all three buckets. A knee that also lost a meniscus, tore a side ligament or has an unusually steep slope to the top of the shin bone puts extra strain on the graft. If those problems were not recognized the first time, the graft was working against the odds from day one. Identifying which buckets apply is the core task before any revision is planned.

Tunnel position, fixation and the graft's weakest months

Picture the femoral tunnel as the hinge point of a door. Move the hinge an inch and the door still opens, but it scrapes, sticks and eventually warps. The ACL’s natural attachment on the thigh bone is a small, specific patch on the inner wall of the outer knuckle of the femur. Tunnels placed too far forward or too high on that wall create a graft that is tight when the knee is straight and slack when it bends, which is exactly the position where cutting and pivoting happen. Over hundreds of thousands of cycles, that mismatch can stretch the tissue.

Tibial tunnel position matters too. A tunnel that is too far forward can cause the graft to rub against the roof of the notch every time the knee straightens, wearing it thin. Surgeons reviewing a failed graft look hard at these positions on X-ray and CT, because a malpositioned tunnel usually cannot be reused as it is.

Fixation is the second mechanical concern. Grafts are held with screws, buttons, pins or staples while the bone grows in around them. If a device loosens, if the bone plug does not incorporate, or if a soft-tissue graft slides within its tunnel, the ligament may loosen before healing ever completes.

Then there is time. The graft is strongest on the operating table. Over the following weeks it weakens as the old tendon cells die off and new ones move in, a process often called ligamentization. Strength gradually rebuilds over many months. This is why rehabilitation is staged, and why MedlinePlus and NHS guidance describe a return to full sport that stretches to around six months or longer, with Mayo Clinic noting that many surgeons now advise a wait of nine months or more for pivoting sports (MedlinePlus; NHS; Mayo Clinic). Return before the tissue is ready is not a moral failing. It is a biological mismatch, and it is one of the most correctable risk factors the second time around.

How is a failed ACL graft diagnosed?

The assessment usually begins with a conversation rather than a scan. The surgeon wants to know how the knee felt in the months after the first operation, whether it ever felt fully stable, what the person was doing when it gave way, and whether there have been episodes of buckling since. That history alone often points toward one of the three causes.

Examination follows. Two manual tests are central. The Lachman test checks how far the shin slides forward under the thigh with the knee slightly bent; excess motion suggests the graft is not restraining it. The pivot shift test reproduces the rotational instability that people describe as the knee giving way, and it is the finding that correlates most closely with how a knee behaves in sport. The surgeon will also check the side ligaments, the back of the knee, the meniscus and the alignment of the whole leg, because each of these can change the surgical plan (Johns Hopkins Medicine).

Imaging then answers the questions the hands cannot. Plain X-rays show tunnel position, hardware and overall alignment. MRI shows whether the graft is intact, stretched or absent, and reveals meniscal tears, cartilage damage and bone bruising from a fresh injury. A CT scan is frequently added before revision because it measures the width of the existing tunnels precisely and shows whether the bone around them has been hollowed out, a finding called tunnel widening that strongly influences whether surgery can be done in one stage or two (Cleveland Clinic).

Imaging also has limits. A graft can look continuous on MRI yet be functionally loose, and a knee that examines as stable rarely needs revision because of an imaging finding alone. The diagnosis is a synthesis: history, examination and pictures together. When any one of them disagrees with the others, a good team pauses and looks again rather than booking an operation.

Who is usually offered revision, and who is asked to wait

Not every failed graft leads straight to a second reconstruction. The decision hinges on how much instability the knee produces in the life the person actually lives, and on whether the knee is ready for another major operation.

Revision is most often discussed for people who have recurrent giving way during daily activities or who want to return to sports that involve cutting, pivoting and landing. It is also considered when instability threatens the rest of the joint. Each episode of the shin sliding forward can pinch the meniscus and scuff the cartilage, so ongoing laxity in a young, active person is a reason to act rather than watch (Mayo Clinic).

Some people are asked to wait, and the reasons are practical. A freshly injured knee that is swollen and cannot fully straighten or bend tends to do poorly in surgery; regaining motion first lowers the risk of postoperative stiffness. Widened tunnels that need bone grafting mean a staged plan, with months between procedures. An unhealed fracture, an active infection, or skin that is not yet settled from the previous incision are all reasons to pause.

Others may not need revision at all. Someone whose knee is loose on examination but who has no giving way, has no interest in pivoting sport, and has good muscle control may reasonably choose bracing, strengthening and activity modification, with the option of surgery kept open. NHS guidance on knee ligament surgery emphasizes that reconstruction is chosen for instability that interferes with function, not for the imaging finding alone (NHS).

Age, weight, smoking and diabetes do not rule anyone out, but they shape expectations for healing and are part of the discussion. The through-line is that this is a shared decision, made with the surgeon and physical therapist, and it is allowed to take some time.

How revision ACL reconstruction differs from the first operation

A first ACL reconstruction is carried out in a knee that, apart from the torn ligament and perhaps a meniscus, is anatomically untouched. A revision is carried out in a knee that has already been operated on, and that changes almost every step.

The old graft and its fixation come first. Remnants of the failed graft are removed so the surgeon can see the true footprints of the ligament. Screws, buttons or pins may need to be taken out if they sit where the new tunnel must go; if they are well out of the way, some are left in place to avoid creating extra holes in the bone (Cleveland Clinic).

Tunnels are the central puzzle. If the original tunnels were in a good position and have not widened, the surgeon may be able to reuse them, sometimes drilling slightly larger to reach fresh bone. If they were malpositioned, new tunnels have to be created that avoid breaking into the old ones, which is like drilling a new hole in a wall already weakened by an earlier one. Surgeons use different drilling angles, divergent tunnels, or specialized fixation to work around this. Occasionally the old tunnel must be filled with bone graft and allowed to heal before a new one can be made, which is the basis of two-stage surgery.

Graft choice widens. A hamstring or patellar tendon already harvested from that knee is gone, so the surgeon may take tissue from the quadriceps tendon, from the opposite knee, or use donor tissue (Johns Hopkins Medicine).

Finally, revision surgeons look beyond the ACL more aggressively than they might at a first operation, adding procedures to the meniscus, the lateral side of the knee or even the bone alignment when those contributed to failure. The operation is usually longer, and the planning behind it is far more individualized.

Which graft is used the second time? A comparison

No single graft is right for every revision. The choice depends on what was used before, the size of the tunnels, the sport the person wants to return to, and the surgeon’s experience. The main options are summarized below; the evidence does not crown a clear winner, and reputable patient guidance describes each as a reasonable choice in the right circumstances (Mayo Clinic; Johns Hopkins Medicine).

Graft	What it is	Often chosen when	Common trade-offs discussed
Bone-patellar tendon-bone (own tissue)	Middle strip of the kneecap tendon with a bone block at each end	Not used at the first surgery; tunnels need bone-to-bone healing	Front-of-knee pain and kneeling discomfort; very secure bony fixation
Quadriceps tendon (own tissue)	Strip of the thick tendon above the kneecap, with or without a bone block	Both hamstring and patellar tendon already used or unsuitable; a large graft is needed	Thigh weakness early on; large, robust graft diameter
Hamstring tendons (own tissue)	Two tendons from the inner thigh folded into a bundle	Not harvested previously; patient prefers to avoid kneecap-area harvest	Soft tissue only, so tunnel healing is slower; some hamstring weakness
Opposite-knee tissue	Any of the above taken from the uninjured leg	Same-side options exhausted	Both knees recover at once; second harvest site
Donor tissue (allograft)	Screened tendon from a tissue bank	Avoiding another harvest; multiple ligaments need rebuilding	Slower biological incorporation; younger, high-demand patients are often steered toward own tissue

A few themes recur in surgical discussions. Own tissue tends to incorporate faster than donor tissue, which matters in a knee that has already failed once. Bone blocks help when tunnels are enlarged because bone heals to bone predictably. Graft thickness is checked against the patient’s size, since an undersized graft is one of the recognized technical reasons a first reconstruction can stretch. Whichever option is chosen, the reasoning should be explained in plain terms, and it is fair to ask why this graft, for this knee, now.

When is two-stage ACL revision needed?

Two-stage revision means the ligament is not rebuilt at the first operation. Instead, the surgeon removes the failed graft and hardware, cleans out the old tunnels and packs them with bone graft, then waits for that bone to heal before returning months later to drill fresh tunnels and place the new ligament (Cleveland Clinic).

The usual trigger is tunnel widening. After a first reconstruction, the bone around a tunnel can slowly erode, sometimes because the graft moved slightly with each step, sometimes because fluid from the joint tracked into the tunnel, sometimes because the fixation sat far from the joint and allowed the graft to piston. On a CT scan the tunnel looks like a cavern rather than a drill hole. A new graft placed into a cavern has nothing to heal against and cannot be held tightly, so the bone must be rebuilt first.

Other reasons include tunnels so badly positioned that a new one would inevitably merge with the old, hardware that cannot be removed without leaving a large defect, an infection that must be fully cleared, and a knee so stiff that motion has to be restored before a graft is placed.

The interval between stages is measured in months rather than weeks, because bone graft needs time to consolidate, and the surgeon will typically confirm healing on imaging before scheduling the second operation. During that interval people are usually encouraged to keep the knee moving and the thigh muscles working, often with a brace for pivoting activities.

Staging is a source of frustration, and understandably so; it doubles the surgeries and stretches the timeline. The reasoning is that a single-stage revision into poor bone is one of the recognized paths to a second failure. Asking the surgeon to show you the tunnel measurements on the CT, and to explain the threshold they use for staging, usually makes the plan easier to accept.

Fixing the whole knee: meniscus, alignment and the lateral side

A revision surgeon’s mantra is that the graft did not fail alone. The ACL shares the job of stabilizing the knee with several partners, and if any of them is compromised the new graft inherits the extra work.

The meniscus is the most common partner. These two crescent-shaped cartilage cushions do more than absorb shock; the medial meniscus in particular acts as a secondary brake on forward sliding of the shin. A knee that has lost a large part of it puts noticeably more strain on the ACL. Where possible, torn meniscus is repaired at revision. Specific tears at the back of the lateral meniscus, called ramp lesions and root tears, are now actively sought because they are easy to miss and important for stability (Mayo Clinic).

The lateral side of the knee is the second partner. A thickened band of tissue on the outer knee, the anterolateral complex, helps control rotation. In revision cases, and in some high-risk first operations, surgeons may add a lateral extra-articular tenodesis: a strip of the iliotibial band on the outside of the thigh is routed under a ligament and fixed to the femur to act as a rotational check-rein. The aim is to protect the new graft during the months when it is weakest.

The third partner is bone shape. If the top of the shin bone slopes steeply backward, gravity and muscle pull tend to push the tibia forward with every step, loading the ACL constantly. When the slope is unusually steep and the graft has already failed once, some surgeons discuss a slope-correcting osteotomy, an operation that removes a wedge of bone to flatten the plateau. It is a bigger procedure with its own recovery and is reserved for selected cases.

Each addition lengthens surgery and rehabilitation. Each is also a direct response to a specific reason the last graft failed, which is why the workup before revision is so thorough.

Revision ACL surgery recovery: what the weeks and months look like

Recovery after revision follows the same shape as after a first reconstruction, but the pace is usually slower and the milestones more cautious. Published patient guidance for primary surgery gives the framework; revision programs typically stretch each phase (MedlinePlus; NHS).

The first days are about swelling, pain control and protecting the repair. Most people go home the same day or after one night with crutches and often a brace, and are encouraged to straighten the knee fully and gently bend it early, because stiffness is a known risk in a knee that has been operated on twice. Pain relief is directed by the surgical team; the goal is enough comfort to do the exercises, not to feel nothing. Anticlotting measures, from early walking to compression or medication where indicated, are decided by the team based on individual risk.

Weeks two to six usually bring weaning off crutches, a normal walking pattern, and the start of quadriceps and hip strengthening. If the meniscus was repaired or an osteotomy was performed, weight-bearing may be restricted for longer, and the therapist will set those limits with the surgeon.

The middle months focus on strength, balance and control. Stationary cycling, leg press, step-downs and single-leg balance work rebuild the muscle that guards the graft. Straight-line jogging is usually introduced only once strength and hop tests approach the uninjured side.

Return to pivoting sport is the last and most debated milestone. For a first reconstruction, NHS guidance describes around six months as a common point to consider sport, while Mayo Clinic notes that many surgeons now recommend waiting at least nine months, with athletes often taking a year or more (NHS; Mayo Clinic). After revision, teams tend to sit at the longer end of these ranges, and many use objective criteria rather than the calendar: symmetrical strength, confident landing mechanics and a knee that no longer swells with load. Milestones are individual, and the timeline belongs to the treating team, not to a chart.

What people often get wrong about ACL re-tear after surgery

“The graft failed, so the first surgeon did a bad job.” Technical error is one cause, but a well-placed graft can still tear under a genuinely violent injury, and biology varies from person to person. Most surgeons who see revisions describe a mix of factors rather than a single culprit. Asking for the operative report and imaging from the first surgery is reasonable; assuming blame is not.

“If it hurts, the graft has failed.” Pain after ACL reconstruction has many sources: kneecap tracking, scar tissue, a prominent screw, or the meniscus. Instability, the knee giving way, is the signature of graft failure, and it can occur with surprisingly little pain (Cleveland Clinic).

“The graft was fully healed at six months, so it was safe to play.” Six months is when many people feel strong. The tissue, however, is still remodeling well beyond that point, which is why Mayo Clinic notes the trend toward waiting nine months or longer for pivoting sport (Mayo Clinic). Feeling ready and being ready are different measurements.

“A revision is just the same operation again.” Revision involves removing old tissue and possibly hardware, navigating existing tunnels, often choosing a different graft and sometimes adding procedures to the meniscus or lateral knee. It is a distinct operation with its own planning.

“Donor tissue is always weaker” or “my own tissue is always better.” Neither absolute holds. Donor grafts incorporate more slowly and are used more selectively in young, high-demand athletes, but they remain an appropriate option in many revision scenarios (Johns Hopkins Medicine).

“Once I have had two surgeries, sport is over.” Many people return to activity after revision. What changes is the length and rigor of the pathway back, and the seriousness with which the whole knee, not just the ligament, is addressed.

Can acl graft failure be prevented the second time?

Nobody can promise a graft will hold. What a careful team can do is remove as many of the known contributors as possible, and this is where the thorough workup before revision pays off.

Technical factors come first. Anatomic tunnel placement, a graft sized to the patient, secure fixation close to the joint, and staged bone grafting when tunnels are widened are all within the surgeon’s control. So is the decision to repair a torn meniscus rather than remove it, and to address a lax lateral side or a steep tibial slope when those are present.

Biological factors are shared. Choosing own tissue over donor tissue for a young athlete, allowing enough time for the graft to mature, and avoiding smoking, which impairs tendon and bone healing, all tilt the odds. Good nutrition and management of conditions such as diabetes support healing as well; these are conversations for the surgical team and primary care clinician rather than reasons for self-directed changes to any prescribed medicine.

Behavioral factors belong largely to the patient and therapist. Completing the full rehabilitation program, meeting objective strength and hop criteria before running or pivoting, and progressing gradually through sport-specific drills all matter. Injury-prevention programs that train landing mechanics, hip and trunk control, and deceleration have been widely adopted in team sports and are commonly built into late-stage rehabilitation (Mayo Clinic).

Sport choice is the hardest conversation. The activities most likely to tear a graft are the same ones people most want to return to. Some choose to return with a longer runway and ongoing prevention training. Others decide that the second time changes the math and shift toward lower-pivot activities. Both are legitimate. The role of the care team is to lay out the evidence honestly, without either alarm or false reassurance, and then support the decision the person makes.

Questions to ask your care team

Revision planning generates a great deal of information in a short time. Bringing a written list, and a second pair of ears, makes the consultations more useful. The questions below are the ones revision patients most often wish they had asked earlier.

• What do you believe caused my graft to fail, and which findings on the exam or imaging support that?
• Were my original tunnels in a good position? Can they be reused, or will you need new ones?
• Do my tunnels show widening on CT, and does that mean a one-stage or two-stage plan?
• Which graft do you recommend for me, and why that one over the alternatives?
• Will hardware from the first surgery be removed, and does that change the recovery?
• Did I have any meniscus, cartilage, side-ligament or alignment problems that need attention at the same time?
• Are you planning a lateral extra-articular procedure, and what is the reasoning in my case?
• What will weight-bearing, bracing and motion restrictions look like in the first six weeks, and do any additional procedures change them?
• Which objective tests will you use to decide when I can run, cut and return to sport, rather than a date on the calendar?
• What are the main risks of this revision for me specifically, including stiffness, infection, clots and the possibility of another failure?
• If I chose not to have surgery, what would you expect for my knee over the next several years?
• Who do I contact after hours if something feels wrong, and what signs should prompt that call?

None of these questions has a single correct answer. A team that welcomes them and explains its reasoning is giving you something more valuable than any statistic: a plan you understand well enough to follow.

When to call your doctor

Two situations call for contacting a clinician, and they look different.

The first is the knee that has previously been reconstructed and now feels wrong. Seek assessment promptly if the knee gives way, buckles or feels like it slips out of place, particularly after a pop or a twisting injury; if it swells within a few hours of an incident; if it locks or cannot fully straighten; or if you have a persistent sense that it can no longer be trusted on stairs, slopes or uneven ground. These are the features that suggest graft or meniscus injury and warrant examination and imaging rather than waiting (MedlinePlus; Mayo Clinic). A knee that hurts without any of these is still worth reporting, but is less likely to be a failed graft.

The second is the knee that has just undergone revision surgery. Contact the surgical team the same day, or seek urgent care, for any of the following red flags:

• Fever, chills, or a wound that becomes increasingly red, hot, swollen or leaks fluid or pus.
• Calf pain, calf swelling or tenderness, which can signal a blood clot.
• Sudden shortness of breath, chest pain or coughing up blood, which can signal a clot that has traveled to the lungs; call emergency services.
• Pain that escalates rather than settles, or is not controlled by the plan you were given.
• Numbness, persistent tingling, or a foot that is cold or pale.
• A sudden inability to bear weight, a new pop, or a feeling that the knee has shifted.
• Rapidly increasing swelling that makes the knee feel tight and hard to bend.

Recovering knees ache, swell and stiffen, and most of that is expected. The team that operated on you would rather hear about a symptom that turns out to be nothing than miss one that mattered. When in doubt, call.

Frequently asked questions

Why do ACL grafts fail after surgery?

Grafts fail for three overlapping reasons: a new injury during sport or a fall, technical issues such as a tunnel drilled away from the ligament’s natural attachment or fixation that loosened, and biological factors like returning to pivoting activity before the tendon has remodeled into ligament-like tissue. Missed meniscus tears, lax side ligaments or a steep tibial slope can add strain. Most revision surgeons find more than one contributor when they review a failed knee.

What does an ACL re-tear after surgery feel like?

The hallmark is the knee giving way or feeling unstable when turning, stepping off a curb or changing direction, sometimes with a pop and swelling after a specific incident, sometimes as a gradual loss of confidence in the joint. Pain may be mild. Because these features overlap with other knee problems, any new instability in a reconstructed knee should be examined by a clinician rather than self-diagnosed.

How is a failed ACL graft diagnosed?

Diagnosis combines history, physical examination and imaging. Manual tests such as the Lachman and pivot shift assess how much the shin slides and rotates. MRI shows whether the graft is intact and reveals meniscus or cartilage damage. X-rays and often CT show tunnel position, hardware and tunnel widening. No single test is conclusive; surgeons weigh all three together before recommending revision.

How does revision ACL reconstruction differ from a first ACL surgery?

Revision involves removing the failed graft and often the old hardware, deciding whether existing tunnels can be reused or must be avoided, choosing a graft from a site not used previously, and frequently addressing the meniscus, lateral knee or bone alignment at the same time. It is typically a longer operation with more individualized planning, and rehabilitation is usually more cautious than after a primary reconstruction.

When is two-stage ACL revision necessary?

Two-stage revision is usually chosen when the old bone tunnels have widened so much that a new graft could not be held securely, when malpositioned tunnels would overlap new ones, when hardware removal leaves a large defect, or when infection or severe stiffness must be resolved first. The first operation cleans out and bone-grafts the tunnels; the ligament is rebuilt months later once imaging confirms the bone has healed.

What graft is best for revision ACL surgery?

There is no single best graft. Options include the patellar tendon, quadriceps tendon or hamstrings from the same or opposite leg, and donor tissue. Surgeons weigh what was used before, tunnel size, the patient’s age and sport, and the need for bone blocks that heal reliably in enlarged tunnels. Own tissue tends to incorporate faster, which is why it is often favored for young, high-demand athletes.

How long is revision ACL surgery recovery?

Recovery follows the same phases as a first reconstruction but usually at a slower pace. Guidance for primary surgery describes several months before running and around six months or longer before sport, with Mayo Clinic noting many surgeons now advise waiting nine months or more for pivoting activities. Revision programs tend to sit at the longer end of those ranges and rely on strength and hop testing rather than dates.

Can I return to sport after a revision ACL reconstruction?

Many people do return to activity after revision, although the pathway is longer and more structured than after a first surgery. Whether and when to return to cutting and pivoting sports depends on objective testing, how the whole knee has been addressed, and personal priorities. Some people choose to shift toward lower-pivot activities. This decision belongs to the individual in partnership with their surgeon and physical therapist.

What is a lateral extra-articular tenodesis and why is it added at revision?

A lateral extra-articular tenodesis uses a strip of the iliotibial band on the outer thigh, routed and fixed to the femur to act as an additional check on rotation of the knee. Surgeons add it in some revision cases and selected high-risk first operations to share load with the new graft during its vulnerable healing months. Whether it is appropriate depends on the individual knee and the surgeon’s assessment.

Does a failed ACL graft mean the first surgery was done badly?

Not necessarily. Technical problems such as tunnel position are one recognized cause, but a well-placed graft can still tear under a violent injury, and healing varies between people. Age, sport, graft type, timing of return and companion injuries all play a part. Reviewing the original operative notes and imaging with the revision surgeon helps clarify which factors applied without assigning blame.

References

• MedlinePlus: Anterior cruciate ligament (ACL) reconstruction
• NHS: Knee ligament surgery

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.