Subchondroplasty is a minimally invasive procedure that primarily targets and fills subchondral bone defects. These defects, also known as Bone Marrow Lesions (BML) occur in the spongy cancellous bone that lies under the cortical bone. As a fairly new technique in the market, Subchondroplasty procedure is mostly used to treat pain that occurs as a result of osteoarthritis.

The SCP procedure is performed with the use of a bone marrow substitute which is filled into the bone marrow lesions and is normally performed along with arthroscopy of the nearby joint. This allows the orthopedic surgeon to visualize and treat any defects inside the joint.

Often, the surgeon will base a diagnosis of a subchondral bone defect on the patient’s clinical history, physical exam, and MRI findings. Bone marrow lesions usually represent a healing response surrounding small defects in the subchondral bone.

Causes of a Bone Marrow Lesion (BML)

Bone marrow defects usually occur when the joints are unable to carry the weight of the individual hence becoming chronically damaged. This can be as a result of:

• Osteoarthritis
• A bone injury that doesn’t heal properly
• Stress reaction that forms from overuse of poor joint mechanics
• Obesity
• Patients with poor joint alignment are more likely to develop BML
• The rapid increase of activity in adults

Idea Candidate for Subchondroplasty Procedure

An ideal candidate for subchondroplasty procedure should present some of the following indications:

• Generally, individuals with bone marrow defects
• Individuals with an isolated Bone Marrow Lesion
• Those with a healthy weight
• Those with subchondral bone stress that’s likely to heal on its own
• Individuals with repetitive microinjuries that lead to bone marrow lesions

Subchondroplasty Procedure

The SCP procedure normally consists of four major components: preoperative plan, targeting the bone defect, assessing the defect, and filling the bone defect.

The procedure is done under local anesthesia, which is administered to the patient at the beginning. Then specialist places a reference frame on the patient’s tibia bone. Using this frame, a pin is inserted under the guidance of fluoroscopic imaging. The pin is further inserted into the desired depth inside the bone with the use of a cannulated drill. The specialist then removes the frame, leaving the pin inside.

A cannula is the placed over the pin which is slid into the bone until it is firmly. At the back of the cannular, the lock of the syringe, which is filled with the bone substitute is attached. The bone substitute material is then injected into the subchondral bone by applying steady pressure. Afterwards the delivery syringe is detached from the cannular after injecting the bone substitute.

The doctor then inserts a trocar into the cannula to fill the bone substitute, which is left, in the bone. Finally, the doctor removes the cannula and confirms the final placing of the substitute by fluoroscopic imaging.

Advantages of Subchondroplasty

• The procedure is minimally invasive
• It is an outpatient procedure – same day discharge
• It may lead to significant pain reduction
• Does not hinder total knee replacement if required in the future
• The procedure ensures fast recovery and resumption of normal activities.

What You Should Expect After Subchondroplasty Procedure

After the procedure, you will experience pain and discomfort for up to two days after which it will decrease gradually in the next 1 – 2 weeks. To relieve the discomfort, pain medications will be prescribed. Additionally, crutches will also be recommended for up to two weeks in order to decrease weight bearing on the treated leg. This is followed by physiotherapy which can last for up to four months, while normal activities like exercise can be resumed after 6 – 8 weeks or as advised by your physiotherapist.