Knee osteonecrosis

If a large portion of the bone surface is affected, or if your pain does not improve with non-surgical treatment, surgery may be recommended. 

There are several different procedures depending on the extent of the injury, age, and length of time:

Arthroscopic debridement to help promote blood flow and induce a healing reaction

• Decompression perforations (microfractures) This procedure consists of creating channels to decompress and encourage new blood vessels to nourish the affected areas of the knee.
• Osteochondral graft (bone and cartilage). A bone graft is healthy bone tissue that is transplanted to an area of the body where it is needed. The tissue can be taken from a donor (allograft) or from another bone in your body (autograft) using various techniques such as mosaic-pasty.
• Autologous chondrocyte implantation (ACI). This is a two-stage procedure. In the first stage, your doctor performs an arthroscopic procedure to remove a small amount of cartilage-producing cells (chondrocytes) from your knee.

These chondrocytes are sent to a laboratory where they are cultured (multiplied) for up to 6 weeks to get more cells.

In the second stage, your doctor performs another procedure to implant the chondrocytes in the area of your knee with cartilage loss. The cells then grow in the joint, replacing the damaged cartilage with healthy cartilage.

Osteotomy: In an osteotomy, a change in the bone's load axis is performed. Changing the weight of the damaged side of the joint will help relieve pain and improve function.

Total or unicompartmental (partial) knee prosthesis If the disease has progressed to the point where the bone has already collapsed, you may need surgery to replace the damaged parts of your knee.

For most patients, treatment for osteonecrosis is successful in relieving pain and improving function.

However, results vary depending on the stage of the disease at diagnosis and the type of treatment.