Subchondroplasty Procedure

There are many reasons to see an orthopedic surgeon for knee pain. One such reason is the development of a Bone Marrow Lesion which may give you similar signs and symptoms as a meniscus tear would (e.g knee pain localized to one area of the knee, pain with activity, possible swelling).

Bone Marrow Lesions (BML) are often-painful defects of the spongy cancellous bone near a joint. They can be found in the bone near any joint that experiences weight-bearing or repetitive motion stress and strain. In some patients, these defects are a result of a bone injury that doesn’t heal properly. In others, BML defects are a stress reaction from overuse or altered joint mechanics. Most commonly we see these lesions around the knee joint in either the tibia or femur.

BML are typically not visible on X-rays. They are diagnosed using certain types of MRI, where they appear as a hazy white area against the background of darker bone. The hazy white area is referred to as bone marrow edema and represents an inflammatory response within the bone. Pathologists have shown that these BML represent a healing response surrounding trauma, such as microtrabecular fractures of the subchondral bone. These may be read as “insufficiency fractures” on the MRI report.

If this healing response fails, physicians usually recommend a course of conservative care, including pain medications, antiinflammatories, crutches, joint braces, injections, among others. In some patients, this treatment will allow the body to heal the subchondral bone defect. If conservative care is unsuccessful, however, the Subchondroplasty (SCP®) procedure may be an option.

The SCP® Procedure is usually performed along with arthroscopy (“scoping”) of the nearby joint, to allow for treatment of any pathology inside the joint. This is usually done in the operating room under general anesthesia. Two or three small incisions are made around the knee during the procedure. During the SCP® surgery, a small, drillable cannula is inserted minimally-invasively into the area of the bone defect. Intraoperative X-ray is used to assist with targeting the defect. Bone Substitute Material is then hydrated and mixed into an injectable paste, and is delivered through the cannula to fill the bone defect. Once the BSM has hardened, the cannulas are removed and surgical wounds closed.

Patients go home about an hour after the procedure. Some patients may require the use of crutches for a few days following the procedure, but may progress to full weight-bearing as early as the day of surgery.
The ideal candidate does not have much arthritis in the knee joint, but instead has an isolated lesion with surrounding edema (inflammation within the bone) which is painful.