Osteochondritis dissecans

Patients in their teens and twenties who have knee pain can often have a condition called osteochondritis dissecans, or OCD.  In this condition, there is an area of bone and cartilage in the knee which is becoming loose, and painful.  The reasons why OCD’s occur is not completely understood; however, diagnosing and managing them correctly is critical to ensure the long term function of the knee.

An OCD lesion can be difficult to spot on xray, but MRI is very accurate. These OCD’s typically occur on the inside of the knee, but can occur anywhere, including on the knee cap.

It is important to treat OCD lesions, as they can become loose, and detach from the knee, leaving a large and painful bone and cartilage defect.

In very young patients who have a lot of growing to do, and where the OCD is mostly still attached, a period of 6 or 12 months from sport can give the lesion a chance to heal.  If the lesion does not heal after 12 months, if the patient is older and mostly grown (i.e 15 o4 16), or if the OCD is becoming loose, surgery may be indicated.

There are two main options for surgery.  If the OCD is very stable, and attached to the bone underneath it, drilling the lesion with a wire can encourage blood flow and healing. 

If the OCD is starting to detach, it is best to fix with screws. 

Postoperative rehabilitation

OCD surgery is performed as day surgery at Women’s College Hospital. Someone must come and pick you up and take you home. All patients will be provided with a script for medications that should be filled at the hospital prior to going home. Medications will usually be Celebrex in the morning for 3 days, Aspirin at night for two weeks, and Tylenol regularly for the first week. A script for Oxycodone will also be provided.

Patients must use crutches for 6 weeks, and wear a brace to sleep and walk for the first 6 weeks. The brace is removed after 2 days to begin bending the knee, when sitting in a chair.  If possible, patients should rent a Gameready machine, which provides ice and compression to the knee, significantly reducing postoperative pain. The information for the rental company will be provided to you.

Physiotherapy is required twice a week, immediately after surgery.  A physiotherapy referral and protocol will be provided for you on the day of surgery. Patients are seen in clinic two weeks after surgery, for wound review. 

Patients should take a week off school after the surgery.  

Risks of surgery

OCD drilling / fixation is a safe operation.  It is typically done arthroscopically, with a 1/1000 risk of deep infection, major stiffness, DVT/PE, and major nerve or blood vessel damage. Patients can get local areas of numbness around the graft harvest incisions, which typically improves over a year or two. Occasionally the surgery is done open, raising the risk of infection to 1/100.

The biggest risk of surgery is that the OCD will not heal. Unfortunately, only 70-80% of OCD treated with screws healed.  Healing will be assessed with a combination of CT scan and MR after surgery.  Most times the screws will be removed 6 months after surgery, in a second operation – it can sometimes be difficult to remove the screws, which is why they are removed 6 months after surgery. 

If the OCD does not heal, further surgery may be required, in the form of cartilage restoration procedures such as AMIC or osteochondral allograft, or with an osteotomy.