Knee Osteochondritis Dissecans (OCD)
PFS or Patellofemoral Syndrome can cause knee pain typically at the front of the knee and under the knee cap. Pain is usually worse after prolonged sitting or going down stairs.
PFS is also known as "movie-goers knee" because pain often begins upon standing after a period of prolonged sitting.
PFS or Patellofemoral Syndrome can cause knee pain typically at the front of the knee and under the knee cap. Pain is usually worse after prolonged sitting or going down stairs.
What is OCD?
Osteochondritis Dissecans (OCD) is a condition that can affect the knee joint and is most commonly seen in children and adolescents. The condition involves both the bone (osteo) and articular cartilage (chondritis), which is the smooth covering of the end of the bone. OCD is damage or degeneration of this cartilage and bone complex. Various types of OCD lesions exist, ranging from mild to severe. Severe OCD lesions can lead to cartilage defects and free-floating pieces of cartilage and bone within the knee joint. While we will focus on OCD lesions of the knee in this section, it’s important to realize that OCD lesions can occur in other joints such as the elbow and ankle
What causes an OCD lesion?
The actual cause of OCD is unknown, however, it is thought that a lack of blood supply to the subchondral bone can cause structural damage to the bone, which supports the cartilage. The combination of this and some form of trauma can cause the cartilage and bone complex to be damaged. The exact cause of this disrupted blood supply is unknown, although possible causes include trauma or repetitive stresses (i.e. running, jumping, etc.), medications such as prolonged use of steroids, and sometimes it just happens. As in many orthopedic conditions, a hereditary component may have a role.
Symptoms:
The most common symptoms are poorly localized knee pain and recurrent episodes of knee swelling associated with activity. Mechanical symptoms (i.e. knee locking/catching/buckling) are evidence of advanced disease, often related to free-floating pieces of cartilage and subchondral bone disrupting joint motion.
Diagnostic Testing:
X-rays are usually first ordered to evaluate for fracture and arthritis. An MRI is usually ordered to further characterize the OCD lesion (i.e. size, degree of subchondral bone involvement, etc…)
Treatment Options:
Treatment depends on the age of the patient, severity of the OCD lesion, and activity level of the patient.
Stable lesions are often able to be treated nonoperatively. The stability of the OCD is usually best determined by the findings on the MRI, based on the presence of edema around the OCD lesion. Nonoperative treatment consists of at least 6 and often 12 weeks of restricted weightbearing and a special knee brace (i.e. unloader brace) that is designed to take pressure off the OCD lesion and allow for healing.
Surgical Treatment:
Unstable lesions, patients who have mechanical symptoms (locking, catching, buckling), and those patients failing nonoperative management are usually indicated for surgery. There are a variety of surgical techniques used to treat OCD lesions. It is important to realize that the most appropriate treatment is dependent on a host of factors that are case dependent.
Dr. Steven Lee will perform a knee arthroscopy, which entails making small incisions (1 inch in length) in the knee and using a small video camera and other small instruments to access the lesion. From there, the treatment will depend on the status of the OCD. If the OCD piece is large and structurally sound enough, Dr. Lee will make every attempt to heal this piece with various pins or screws. If the piece is large enough and not able to be repaired, a graft either from yourself (autograft) or from a donor (allograft) may be utilized.
For the smallest lesions, microfracture surgery may be employed, which involves cleaning the cartilage defect surface and then drilling into the bone of the cartilage defect. Drilling into the bone releases growth factors from the bone marrow that helps create pathways for new blood vessels to nourish the affected area, leading to filling in of the cartilage defect with fibrocartilage. While fibrocartilage is not the same as articular cartilage, it is structurally similar and can lead to a significant decrease in symptoms.
Dr. Steven Lee is currently the Associate Director of the NISMAT, the first institute in the country dedicated to sports medicine research, and is part of the teaching faculty of the Lenox Hill Sports Medicine Fellowship program, the oldest fellowship in the country. As such, he is not only current with the most advanced techniques available today to treat this complex problem, but is also involved in research to advance the treatment for the future.
Recovery Expectations:
While the post-op protocol varies depending on the procedure formed, patients can generally expect to leave the operating room immobilized in a knee brace and remain non-weightbearing with crutches. Crutches and a knee brace are usually required for at 6 weeks after surgery. After this, an unloader brace may be prescribed. This period of nonweightbearing and immobilization is very important towards OCD lesion healing. Patients can then expect to undergo anywhere from 6-12 weeks of physical therapy in an effort to regain back motion and strength of the affected joint. Most patients return to sports 4-6 months after surgery.
Immediate Post-Operative Instructions
Please refer to the following pages for more information:
*It is important to note that all of the information above is not specific to anyone and is subject to change based on many different factors including but not limited to individual patient, diagnosis, and treatment specific variables. It is provided as an educational service and is not intended to serve as medical advice. Anyone seeking specific orthopedic advice or assistance should consult Dr. Steven Lee or an orthopedic specialist of your choice.
*Dr. Steven Lee is a board certified orthopedic surgeon and is double fellowship trained in the areas of Hand and Upper Extremity Surgery, and Sports Medicine. He has offices in New York City, Scarsdale, and Westbury Long Island.