Cartilage Injuries in the knee: Evaluation and Treatment

Matthew A. Handling, M.D.

Cartilage is the strong and smooth substance that makes up the gliding surfaces in our joints. It is made up of cells call chondrocytes. Cartilage injuries can occur in any joint but are most-commonly found in weight bearing joints like the knee and ankle. The goal of treatment for any cartilage defect or injury is preserving the person’s normal cartilage to prevent future osteoarthritis. Unfortunately, our bodies do not have the ability to heal or repair a cartilage defect with normal cartilage cells. Luckily, there are many different types of surgical options for cartilage injuries.

The symptoms that people feel for focal cartilage defects include pain, swelling, stiffness, and locking or catching, which can interfere with activities. Traumatic injuries like a knee-cap dislocation or an ACL tear can cause a cartilage defect, but also repetitive overload can produce cartilage damage. An OCD or Osteochondritis dissecans is a specific type of cartilage lesion that occurs in children. Most cartilage defects are diagnosed on an MRI study. This helps determine the size and location of the defect which aids in surgical planning. An MRI will also pick up any other injuries in a knee such as a ligament tear (ACL) or meniscus tear.  

Surgical treatment options include:

1. Debridement/Chondroplasty – This technique involves shaving any loose cartilage back to a stable rim to prevent catching. Benefits include early weight bearing and a quicker recovery, but downsides are that this procedure doesn’t restore normal joint cartilage 
2. Fixation of unstable or loose cartilage fragment – This treatment involves fixing an acute cartilage fragment back into its normal position in the joint with bioabsorbable screws or darts. This is commonly used for Osteochondritis dissecans. The benefits include maintaining the patient’s own cartilage, but the downside is sometimes poor healing.
3. Microfracture – This technique involves poking holes in the bone underneath a cartilage defect to access bone marrow elements and growth factors that can promote healing. This is typically only used for small cartilage defects and heals by forming fibrocartilage (scar tissue cartilage) and not normal articular cartilage. 
4. Osteochondral Autograft – This treatment involves taking an osteochondral (bone + cartilage) plug from a non-weight bearing surface of the knee and moving it to a weight bearing part of the knee. The benefits are moving the patient’s own normal cartilage to area that is damaged. The downside is it can only be used for small defects. 
5. Osteochondral Allograft – This technique involves using a donated bone and cartilage plug/graft. The benefits include using this for larger cartilage defects with good results. Downsides include having to wait for the donor plug to become available.
6. Matrix-Induced Autologous Chondrocyte Implantation – This surgery is a two-stage procedure, with first stage involving a cartilage biopsy at time of arthroscopy. The cell biopsy is then sent to a laboratory for growing cartilage cells which are then re-implanted into the cartilage defect. 

Cartilage injuries can be a challenging problem for patients. The above treatment options will be individualized to each patient based on location, size, and depth of the injury to the cartilage. If you have cartilage injury or would like a second opinion, then contact Dr. Matthew Handling at First State Orthopaedics and make an appointment today.