How a Graft Is Selected
Dr. Montgomery: Hi, I'm Dr. Ken Montgomery from Tri-County Orthopedics. I'm an orthopedic surgeon who specializes in sports medicine as well as hand and upper extremity surgery.
When the anterior cruciate ligament is torn, the quality of the tissue left is no longer good enough to perform a repair. As a result, we need to take good quality tissue from somewhere else to reconstruct the anterior cruciate ligament and create a new graft. This is tissue that we can either obtain from the patient themselves or from somebody else. We take that tissue and we use it to create a new healthy anterior cruciate ligament.
There are many different kinds of graft available to use for an anterior cruciate ligament reconstruction. A few are very popular. There are two options where we take them from the patient themselves, and those are the patella tendon—or at least the central third of the patella tendon. The other option is taking it from the patient themselves is to use the hamstring tendons on the inner side of their knee.
Finally, another option is to take a graft from somebody else. We call that an allograft or cadaver graft. Just like somebody can donate their kidney or liver, they can also donate tendons and ligaments, and those can be used for a ligament reconstruction as well.
One of the most commonly used grafts is the central third of the patella tendon. This is often called the bone tendon bone graft. The central third of the patella tendon is used to create a new anterior cruciate ligament graft.
This graft has a long track record and has been shown to stand up to even high aggressive sports. It's frequently used for athletes participating in aggressive contact athletics at a high level. The advantages are the long track record that this graft has and the fact that we know over the years the patients tend to do well.
The disadvantage of this graft is it's a little bit more invasive. Because the graft harvest involves cutting into the bone, there tends to be a little bit more bleeding, a little bit more soreness after the operation, and also patients can have pain in the front of their knee after they've had this graft taken. That pain is usually temporary. It can last anywhere from several months to as long as a year but typically subsides over time.
I tend to use this graft most commonly in very active athletes who participate in high-end contact sports, typically younger patients in their teens and early twenties, or patients who have very loose ligaments otherwise where it becomes an ideal graft.
The hamstring tendon graft is another graft that's frequently chosen. This is a graft where we take the medial hamstrings from the knee and use them to reconstruct the anterior cruciate ligament. It's a less invasive procedure than the patella tendon graft, and therefore there tends to be less bleeding, pain, and discomfort for the first several days and even the first month after the procedure.
There also tends to be less pain in the front of the knee in the later recovery. Patients, of course, can have some weakness in the hamstrings, and this is countered by performing a hamstring strengthening program as part of the rehabilitation.
This graft is ideal for many patients and is in fact one of the most popular grafts being used in the country. It's cosmetically appealing since it's a much smaller incision than that for the patella tendon graft. So many women will prefer this graft. Because of patients having hyperlaxity or very loose knees and joints from time to time, in those patients it may not be an ideal graft. So, in those patients I may choose a different graft option.
Another graft option is called the allograft or cadaver graft. This essentially is taking the graft from somebody else. So, rather than taking the graft from your own knee, and therefore having the pain and discomfort that comes from either harvesting your own hamstrings or your patella tendon, a person who's died can essentially donate their ligaments or tendons, and these grafts can be used quite easily to do a ligament reconstruction.
The advantage is that the patient, obviously, is going to have less pain or discomfort in the first several weeks after the operation. The disadvantage is that you always heal your own body's tissue to your own body more than you would heal somebody else's tissue. So, there's a small percentage that you may not accept or receive the graft well. In fact, we know that for younger patients, 25 and younger, this graft tends to have a higher failure rate and therefore is probably not something that we should routinely recommend for young patients unless there are not other good options.
There are a number of factors that a patient and their surgeon should consider when selecting a graft for an individual patient. Some of the most important—the patient's age, their activity level, and which sports they're participating in—should all be on the forefront of how the decision is made on which graft should be chosen. Other factors that come into play—what's life going to be like for the first month to six weeks after surgery. That can have an impact on which graft you choose as well.
There are multiple different graft options that are available to the patient. I would recommend that you find a surgeon who feels comfortable using any and all graft options. That way the surgeon can choose the graft that fits your needs the best rather than choose the graft that fits their needs the best. Find a surgeon that can do each operation equally well, and that way the pros and cons can be delivered in an honest fashion and you can help the surgeon determine what's the best graft for you.