Section Chief of Pediatric Orthopedic Surgery at the Hackensack University Medical Center, Dr. Amit Merchant, and Vice Chairman of the Department of Orthopedic Surgery at the same medical center, Yair Kissin, MD, talk about a new way to treat ACL tears without using the patient’s healthy tissue or a cadaver.
Interview conducted by Ivanhoe Broadcast News in 2023.
What does BEAR stand for?
Merchant: BEAR stands for Bridge Enhanced ACL Restoration. This is a relatively newer technique of repairing the anterior cruciate ligament and we’ve enhanced it by putting in a bovine collagen graft to help improve the healing environment and allow the ACL to heal itself.
How do you perform this procedure?
Merchant: The BEAR procedure is performed by doing an ACL repair. This is typically done by wrapping sutures around the torn piece of ACL and reattaching it to the bone. What makes BEAR more innovative than former ACL treatments is that we’re also including a collagen graft and we’re placing it into the space where the ACL sits. This creates a small microenvironment of lots of healing factors and regenerative factors that allow the ACL to not only heal itself, but to bring about its normal strength and thickness.
What are the advantages and disadvantages of this procedure?
Merchant: The advantage of performing the BEAR procedure is that we are allowed to restore a patient’s native ACL. We are not removing any of their own tissue. There is some data that shows by preserving as much of the patient’s native ACL, you are also preserving some of those proprioceptive nerve fibers. Proprioceptive fibers help with keeping a knee more stable, allowing a patient to sense if there are abnormal movements happening. Other advantages are the reducing of donor site morbidity. Typically for an ACL reconstruction, we are taking tendon or ligament from another part of the knee to create a new ACL. Now, we have the option of not doing that part of the surgery at all. We’re not having to deal with loss of tendon or ligaments from other parts of the knee
Does an individual heal quicker when given the BEAR procedure?
Merchant: I wouldn’t say they heal any quicker because we they still adhering to the same rehabilitation program. I would say that patients are experiencing less pain. They do feel that they’re back to their normal self at a much faster stage. But, we still are treating them as a reconstruction in terms of their physical therapy, how fast they can advance in their stages of therapy, and how quickly we can get them back into sports.
Are there individuals who don’t qualify for it?
Merchant: Yes, the BEAR is not a blanket procedure that’s going to take over the world. There are certain factors that really allows us to give this option. For starters, we need what we call an ACL stump. An ACL stump is when the injury happens in the middle of the ACL or more towards the higher end of the ACL, this has a better chance of going through a BEAR procedure. Someone that’s torn their ACL towards the lower end, or it’s got badly damaged and a bunch of fibers shredded, don’t have that option of doing the BEAR procedure. They would receive the ACL reconstruction.
Are there age limits?
Merchant: As of now, there are some guidelines with the BEAR procedure. I believe their current guideline says patients no younger than 14 years of age. But there have been reports of younger patients being used for the BEAR procedure.
When was this procedure introduced to the world?
Merchant: BEAR has been around for a number of years. It’s been around for almost eight years. It was developed at a Boston Children’s Hospital. It was recently approved by the FDA and that is what allowed us to really bring this new technology to Hackensack Medical Center.
Can you tell us about the first patient at your hospital who recieved the BEAR procedure?
Merchant: Yes, we have our very first patient who had the BEAR procedure done just about two months ago. So far, it’s been a remarkable recovery. The patient has been having less pain than what we typically expect and their ability to ambulate and move has been much faster. That’s been nice to see.
How did they injure their ACL?
Merchant: Karis is a very avid soccer player. She’s on a high school level with goals of playing in college. This was a soccer-related injury, and we immediately obtained imaging. We got an MRI of her knee, and it showed a very high-grade tear of her ACL.
She’ll be encouraged to wait at least nine months before returning to sports — is this correct?
Merchant: Absolutely. Despite BEAR having all of its wonderful data showing that there’s excellent recovery, there’s still data that shows that returning to sports sooner than nine months has a very high risk of re-ruptures. Nine months is the absolute minimum but the average is usually 12 months. Some patients will take longer than 12 months to get back into their same competitive level of sports.
BEAR seems to be an exceptional procedure. Can we assume there aren’t disadvantages?
Merchant: The disadvantage of performing the BEAR procedure is that it cannot be utilized for every single patient. Patients with a completely shredded or torn ACL where we physically cannot do the repair, this is not an option for them. The way that we are able to repair the ACL is by drilling holes into the femur and into the tibia. That’s how we’re able to anchor the ACL and repair it back to the bone. In a child that’s very skeletally immature, there’s always the fear of – ‘If you have to drill through a growth plate, and things are going to be tethered to hold it in place, are we going to affect the overall growth of that leg?’
Wouldn’t that be true of any ACL surgery? The possibility for growth issues?
Merchant: To a certain degree, yes. For the skeletally mature child, we wouldn’t expect to be much of a growth disturbance. That’s things that we plan preoperatively. We can predict how much more growth is expected, and depending on that, we can determine do they get a standard BEAR procedure or reconstruction with what we call transphyseal techniques. If they aren’t skeletally mature, we’d have to implement a more physeal-sparing technique so that we preserve the growth plates as best as possible.
You mentioned earlier that Bear has been around for a number of years, how are patients doing years post treatment?
Merchant: It’s been around for a number of years, but we don’t have 15-year data or 20-year data on what’s happening to patients that have received a BEAR. Are we essentially saving their knee from premature arthritis? It typically takes 20-30 years for someone to develop arthritis. Are we successfully preventing that from happening?
What else would you like to tell us regarding this topic?
Merchant: I would say another advantage of the BEAR procedure is not having to remove any donor tissue. God forbid, if a patient has a re-rupture of their ACL from a BEAR procedure, we still have what’s necessary to perform a reconstruction.
Can you describe the diferent options there are when performing a traditional ACL resconctruction surgery?
Kissin: During an ACL reconstruction, a ligament from somewhere else in the body is taken and used to replace the torn ACL. There’s an option to use either a part of the patient’s own knee (which is called an autograft) or to use a cadaver graft, which is from a donor’s body. In patients, generally speaking, who are more active like the high-school athletes, college athletes, pros, semi-pros, they would get their own ligament because that’s the more reliable and a little bit more structurally sound ligament. Patients who are older and maybe have a career and a family, but still want to recreationally ski or play their sports, will get a cadaver surgery because the advantage is that it’s a little less surgical trauma. But, it’s also a slightly less reliable ligament. There are certainly pluses and minuses, however, of taking a graft from the patient’s own knee. When you take the front of the knee ligament, you can have pain in the front of the knee. You can even have a fracture of the patella. You can have residual tendinitis. When you take a patient’s hamstring, you can have hamstring weakness. So we rob Peter to pay Paul a little bit to do this operation. Then we go to traditional surgery which is arthroscopically done where we drill holes where the old ACL was. We put this new ligament that we have choices of as we discussed and hold that in with a variety of fixation tools like screws or pins or things like that.
What’s the recovery time on average?
Kissin: The recovery time has certainly shifted. I think when I even first started my career, a few years back, we were sending patients back to sports at the five to six month range and we saw that there were quite a few re-ruptures. Now that needle has moved to more like nine to 12 months of recovery. Patients won’t be happy to hear that they can’t play next season, but it’s a very importnt thing to tell them – despite their tears. These are season ending injuries.
Which group of people is more susceptible to having this injury?
Kissin: The most common injury group are the patients who put the most mileage in twisting sports on their knees. The high school and college basketball players, football players, soccer players, skiers, lacrosse players, and tennis players. It’s very seasonal. As a sports medicine surgeon, we know who to expect in September versus November versus January versus April.
How many of these traditional surgeries would you say you do every year?
Kissin: About two to four of these every week on a Friday.
How many ACL surgeries are done in the United States?
Kissin: About 250 to 300,000. When I was in training in the mid-2000s, that number was closer to 100,000. It’s certainly evolved over time, qand with the advances in medicine these days they might be changing the paradigm a little.
END OF INTERVIEW
This information is intended for additional research purposes only. It is not to be used as a prescription or advice from Ivanhoe Broadcast News, Inc. or any medical professional interviewed. Ivanhoe Broadcast News, Inc. assumes no responsibility for the depth or accuracy of physician statements. Procedures or medicines apply to different people and medical factors; always consult your physician on medical matters.
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