Articular Cartilage Repair | Cartilage Transplant

What is articular cartilage repair or cartilage transplant?

Cartilage is found throughout your body, acting as a cushion between the bones of the joints. Articular cartilage, specifically, is a rare commodity that covers the ends of our bones and allows our bones to move and glide freely without any pain. This cartilage is tough, much like the cartilage (gristle) on the ends of chicken bones. Articular cartilage has no blood or nerve supply, meaning it has poor regenerative or healing potential. When the cartilage is damaged, the joint no longer moves freely and can cause pain. While no study has definitively proved the theory, we believe focal articular cartilage injury can lead to widespread cartilage loss – more commonly known as osteoarthritis.

The ideal candidate for cartilage repair or transplant are those who are younger, athletic, and with no other site of cartilage loss or injury. Often times, these patients have underlying bony anatomy that predisposed them to this cartilage loss, such as a bowlegged deformity (varus knees) or knock-knees (valgus knees). There are many ways to repair the knee’s articular cartilage. The best surgical procedure is selected based on a variety of factors, from age to physical demand to anatomic considerations. The goal is to reduce pain and restore knee function in the short to midterm (2-7 years). To date, it is unknown whether the procedure is likely to prevent or delay the need of a joint replacement! Dr. Prem Ramkumar, cartilage repair and cartilage transplant surgeon, has extensive knowledge in articular cartilage repairs and reconstruction. He is located in Long Beach and serves the Los Angeles, Orange County, and surrounding Southern California areas.

What articular cartilage repair and reconstruction options are available?

If you’re diagnosed with articular cartilage damage and need an articular cartilage repair, there are many options, including: 

• Chondroplasty
• Chondroplasty with Bone Marrow Aspirate Cell Concentrate
• Mosaicplasty or Osteochondral autograft transplant
• Osteochondral allograft transplant
• Matrix-associated autologous chondrocyte implantation (MACI)
• Particulate or minced juvenile articular cartilage

1 – What is chondroplasty and how is it done?

Chondroplasty is a minimally invasive arthroscopic outpatient surgical procedure to repair and reshape the damaged articular cartilage. Dr. Ramkumar will smooth the degenerative cartilage and trim any unstable flaps, eliminating any mechanical symptoms causing pain. This is successful in patients with mild to moderate cartilage damage. It’s also popular with in-season athletes who need a quick recovery. In patients over age 40, bone marrow aspirate concentrate is harvested from the pelvis and used to help stimulate a cartilage-like response at the defect when delivered directly to the area of injury.

2 – What is mosaicplasty and how is it done?

Mosaicplasty is a minimally invasive open surgical procedure used to repair the defect in the articular cartilage using healthy bone and cartilage from non-weight-bearing areas of the knee. The surgery works best on active adults under 45 years old, with smaller defects. The inserted grafts fill most of the defect, allowing the body to grow around the new cartilage to fill in any gaps. This is also known as osteochondral autograft transplant (OATS) or autologous osteochondral transfer (AOT). Since the plugs heal quickly, this is an excellent choice for high-demand athletes and other active adults.

3 – What is osteochondral allograft transplant (OCA) and how is it done?

The osteochondral allograft transplant (OCA) is similar to the OATS procedure, but the graft comes from a donor, not the patient. OCA is the preferred technique to address medium and large lesions involving the bone under the cartilage. After the procedure, the cartilage is stable and early weight bearing is allowed. These larger lesions requiring OCA carry a higher risk of failure compared to a graft from one’s own tissue as with the OATS. There is an element of maintenance after OCA to control synovitis and the potential of graft rejection. This may involve gel injections or reoperation with chondroplasty. There is always the chance the donor graft does not adequately take to the host bone.

4 – What is matrix-associated autologous chondrocyte implantation (MACI) and how is it done?

This is a two-stage procedure that involves harvesting your own cartilage, growing it in the lab for 6-8 weeks to create a scaffold patch, then re-implanting it over the damaged cartilage surface with glue. The cells and scaffold facilitate the creation of durable cartilage repair tissue. This option requires two procedures, does not allow for immediate weight bearing, and carries similar results to an OCA. The benefit is that the cartilage cells come from the patient’s own body, rather than a donor, and is less likely to be rejected. This option is not for patients with underlying bone injury.

5 – What is particulate or minced juvenile articular cartilage and how is it done?

This procedure uses articular cartilage harvested from a juvenile donor. During the surgery, the donor cartilage is grafted into the damaged cartilage, restoring the patient’s cartilage. Since juvenile cartilage cells regenerate quickly, the cartilage lesion has a higher chance of healing in the setting of a well contained defect. Dr. Ramkumar typically reserves this option for patellar lesions.

What is the recovery time for articular cartilage repair or replacement?

Recovery to a state of walking without assist devices is case-by-case dependent. Recovery to sport depends on your fitness, your cartilage lesion, your adherence to protocols, and your sport. Here are some general recovery guidelines for some of the above procedures, but Dr. Ramkumar will provide you with your specific expected timeline after taking into account all relevant considerations:

• Chondroplasty – 2-3 weeks
• OATS – 3-5 weeks
• Osteochondral allograft transplantation and juvenile minced cartilage implantation – 3-5 weeks
• MACI – 6-8 weeks after 2^nd surgery