The Subchondroplasty® (SCP®) Procedure is a minimally-invasive, fluoroscopically-assisted procedure that targets and fills subchondral bone defects through the delivery of AccuFill® Bone Substitute Material (BSM), a nanocrystalline, highly porous injectable calcium phosphate (CaP) which is a a hard-setting bone substitute material that is replaced with new bone during the healing process.
The SCP® Procedure is usually performed along with arthroscopy for visualization and treatment of findings inside the joint. In some cases, an open or mini-open procedure is necessary for access to the defect.
The surgeon will base a diagnosis of a subchondral bone defect on a patient's clinical history, physical exam and MRI findings.
Subchondral bone defects are often referred to as Bone Marrow Lesions, or BML, a term for a finding on an MRI that represents an often painful, abnormal area or defect inside the bone.
Bone marrow lesions (sometimes called Bone Marrow Edema, or BME) are small defects typically found in subchondral bone, the region below the cortical bone near a joint. They can only be seen on certain MRI sequences, appearing as a hazy white area against the background of darker bone.
Pathologists have shown that BML represent a healing response surrounding small defects in the subchondral bone, such as microtrabecular fractures. This type of defect can be found throughout the extremities and pelvis. They can be found in any bone that sees weight-bearing or repetitive motion stress.
The causes of a BML defect are not specifically known. In some cases, these defects are a result of a bone injury that doesn’t heal properly. In other cases, BML may be a stress reaction that forms from overuse or poor joint mechanics.
It is known that:
• Obesity and poor diet are thought to increase the likelihood of developing BML
• BML are more commonly found in middle-aged patients than in younger patients
• Patients with poor joint alignment are more likely to develop BML
• Adults who quickly increase activity may develop BML
AccuFill® BSM is an engineered calcium phosphate mineral compound. It flows readily to fill the subchondral bone defect and hardens quickly into a biomimetic implant once injected. AccuFill® BSM mimics the properties of cancellous bone and is replaced with new bone during the healing process. It's important to note that the use of AccuFill® BSM is not intended to be intrinsic to the stability of the bony structure. Radiological studies need be used to confirm that the adjacent cortical bone is intact.
Patients are typically treated in an outpatient setting, returning home the same day of the procedure. Postoperatively, the doctor will recommend a short recovery course, similar to that of arthroscopy.
It’s important to note that recovery from The SCP® Procedure is different for every patient. However, the following is common for most patients:
• For the first 48-72 hours after surgery, patients will often experience significant pain in the operative area. The doctor will likely prescribe pain medication to treat these symptoms. Always follow the doctor’s advice closely.
• For the initial period, most doctors will recommend walking and standing with crutch support. The use of crutches is typically reduced as tolerated.
• The doctor will also recommend a course of physical therapy and activities to help regain strength and maintain mobility of the joint.
As with every surgical procedure, there are risks and potential complications. Individual results will vary. Success depends on factors such as age, weight and activity level. A health care team can help determine if the patient is healthy enough for surgery. Consult a doctor for a complete assessment of possible risks before deciding to have surgery.
A course of conservative treatment—to include pain medications, joint braces, crutches, physical therapy and/or injections into the joint—may allow the body to heal bone defects sometimes referred to as BML, and is usually recommended before proceeding with any surgical procedure.
If the bone does not heal with conservative care, a doctor may recommend surgery.
Results of any surgical procedure vary from patient to patient. A patient should consult with their doctor to decide what is appropriate for their situation. Should it become necessary, total joint replacement is still another option.
Many surgeons believe that chronic BML will not heal without intervention and can only be detected on MRI. Only your doctor can tell you if you have this condition. And only your doctor can tell you if The Subchondroplasty® Procedure may be right for you.
source: Zimmer Knee Creations, Inc.