What is an articular cartilage injury?
An articular cartilage injury occurs when there is damage to the joint surface. Injuries to the cartilage can be partial thickness (part of the way down to bone) or full-thickness (all the way down to bone). The problem with articular cartilage injuries is that they have very limited ability to heal.
How is the articular cartilage injured?
Cartilage injuries can occur from trauma, such a football tackle or twisting injury, or gradually over time. In addition, there are certain diseases, such as osteochondritis dessicans, which causes damage to an area of cartilage and bone in the knee without a definite cause. When there is significant loss of the articular cartilage, the knee is considered to have “arthritis”.
How do I know my articular cartilage is injured?
Injuries to the articular cartilage most typically cause pain in the knee in the area of the damage. In addition, patients can get swelling, locking, or buckling of the knee. In some cases, it can be difficult to know for sure if cartilage damage is the reason for knee pain.
Do I need x-rays, MRI’s or any other test?
A set of x-rays is usually ordered to evaluate the bones and cartilage around the knee. The x-rays are primarily used to evaluate for arthritis and severity of the articular cartilage injury of the knee joint. If the damage is small, the x-rays may appear normal. A MRI may be ordered to look for damage to the articular cartilage and rule out any other injuries to the knee. In some cases, the damage cannot be seen on the MRI, even though it is present.
Is there other damage to the knee when the articular cartilage is injured?
There is frequently other damage to the knee in cases of articular cartilage damage, which occur at the time of the injury. These include ligament tears or tears of the meniscus. If surgery is needed, all of the injuries will be addressed at the time of surgery.
What are the treatment options for articular cartilage injuries?
Some patients with an articular cartilage injury improve with conservative treatment. The treatment includes exercises, use of anti-inflammatory medications (NSAIDs), and possibly an injection of steroid. The exercise may include a program you can do at home or formal physical therapy. Depending on the extent of the damage, some patients get better with these treatments and do not require surgery. If patients do not get better with conservative therapy, or have a large articular cartilage lesion, surgery may be necessary.
How are articular cartilage injuries treated with surgery?
The surgery for articular cartilage injuries depends on the extent of the problem. There are several surgical options, and which procedure is best depends on several factors. These factors include the patient’s age and activity level, the size of the lesion, and the chronicity (age) of the lesion.
What are the treatment options for articular cartilage injuries?
Some patients with an articular cartilage injury improve
with conservative treatment. The treatment includes exercises, use of anti-inflammatory medications (NSAIDs), and possibly an injection of steroid. The exercise may include a program you can do at home or formal physical therapy. Depending on the extent of the damage, some patients get better with these treatments and do not require surgery. If patients do not get better with conservative therapy, or have a large articular cartilage lesion, surgery may be necessary.
How are articular cartilage injuries treated with surgery?
The surgery for articular cartilage injuries depends on the extent of the problem. There are several surgical options, and which procedure is best depends on several factors. These factors include the patient’s age and activity level, the size of the lesion, and the chronicity (age) of the lesion.
The first step in evaluating the lesion is usually arthroscopy. The arthroscope is a fiber optic instrument (narrower than a pen) which is put into the knee joint through small incisions. A camera is attached to the arthroscope and the image is viewed on a TV monitor. The arthroscope allows me to fully evaluate the entire knee joint, including the knee cap (patella), the cartilage surfaces, the meniscus, the ligaments (ACL & PCL), and the joint lining. Small instruments ranging from 3-5 millimeters in size are inserted through additional incisions so that I can feel the joint structures for any damage, diagnose the injury, and then repair, reconstruct, or remove the damaged tissue.
Once the lesion is evaluated, there are several options for treatment. These include:
- Smoothing of the lesion and removing loose edges only (debridement)
- Techniques to stimulate scar cartilage to grow into the lesion (microfracture)
- Techniques to replace the lesion with new cartilage (osteochondral autografts, osteochondral allografts, or autologous chondrocyte implantation). Each of these techniques is briefly described below.
What is debridement of the articular cartilage?
Debridement is performed by using small arthroscopic instruments, such as a mechanical shaver, to smooth the cartilage edges. This is performed so that there are no loose edges to irritate the joint, and to prevent the area of damage from expanding. Debridement is primarily used for small lesions, or when severe arthritis is found that involves the entire knee joint. Many patients can do well with debridement.
What is the microfracture technique?
Microfracture is a technique to attempt to repair damaged articular cartilage. Small holes are poked into the bone in order to allow blood and marrow healing elements into the area of missing cartilage. This technique allows scar cartilage (fibrocartilage) to fill the area where the cartilage is missing. This technique is easy to perform and can create good results in a lot of patients. However, since the cartilage is scar cartilage, it may not be as durable as other techniques to restore cartilage defects. Microfracture can be performed during an arthroscopy, and no other incision or surgery is needed.
What is an osteochondral AUTOGRAFT?
An osteochondral autograft is a technique to take a small piece of cartilage and bone from one area of the knee and put it in the area that the cartilage is missing. The cartilage is taken from an area in the knee that feels minimal stress, so it is thought that patients do not notice that the piece of cartilage is missing. This technique can be very effective for small areas of missing cartilage. An osteochondral autograft can often be performed by arthroscopic techniques, but sometimes requires an open incision on the knee.
What is an osteochondral ALLOGRAFT?
An osteochondral allograft is a technique to take a piece of cartilage and bone from a cadaver (as opposed to your own knee) and place it in the area that the cartilage is missing. This technique is good when there is a large area of cartilage that is missing, or if there is both bone and cartilage missing (such as cases of osteochondritis dessicans). The donor allograft is testing for bacteria, hepatitis, and HIV. However, there is always a small chance of disease transmission from an allograft. An osteochondral allograft usually requires an open incision on the knee.
What is Autologous chondrocyte implantation?
Autologous chondrocyte implantation is a technique to restore cartilage from your own knee in the area of the cartilage injury. The technique first involves performing an arthroscopy and taking a small piece of cartilage from your knee (biopsy), which is then sent to a lab in Boston. The lab then grows more cartilage cells from the cells given in the biopsy. A second surgery is then performed (about 4 to 12 weeks later) to implant the cartilage cells. This involves an open incision on the front of the knee. A small piece of the outer layer of the bone, called the periosteum, is taken from the lower leg and is sewn in place in the area of the cartilage defect. The cartilage cells are then injected in the area of the defect, and the periosteum is sealed. In many cases, this cartilage then grows into nearly normal articular cartilage.
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