JOIN USAutologous Chondrocyte Implantation (ACI) is a new surgical technique to treat cartilage injuries, enlightens Dr Chandrashekar P.
Articular cartilage is the white shiny covering over the ends of the bone. Articular cartilage has a very unique feature as it is smooth yet tough, and serves well as the bearing surfaces of the joint. Over time, however, cartilage degeneration can lead to osteoarthritis, pain, and disability of the joint. Articular cartilage is produced by chondrocytes, which are cells that divide or multiply very slowly. This is one of the reasons that articular cartilage injuries do not repair well and can lead to continued degeneration and deterioration of joint condition. Articular cartilage injuries can be focal, which is localized and contained, or global, which can lead to joint osteoarthritis.
Causes of articular injury* Injury or trauma, including sports injuries* Repetitive excessive use of the joint* Congenital abnormalities * Hormonal disorders like Osteo-Chondritis Dessicans (OCD)
Symptoms
Most cartilage injuries will lead to swelling, pain, and locking in the joint. The most common joint with symptomatic cartilage injuries are knee, shoulder, elbow, hip and knee. Before your doctor decides which cartilage repair approach is best for you, you will have to undergo a Magnetic Resonance Imaging (MRI) test to determine the severity, size and location of your cartilage injuries. Sometimes MRI misses out cartilage lesion and which are picked up from arthroscopy during surgery.
New surgical technique
Autologous Chondrocyte Implantation (ACI) is the first step to culture human chondrocytes and re-implant them to treat cartilage injuries. Articular cartilage is biopsied or taken from the patient’s knee during arthroscopic surgery. The chondrocytes from the cartilage are then isolated and grown in the laboratory over a 3-4 week period. After a sufficient number of chondrocytes has been cultured, they are injected back into the defective area of the knee. Over a period of time they form what is known as hyaline-like cartilage which resembles the native joint cartilage. This technique is the first cell-based type treatment of cartilage injuries.
Following implantation there is a period of restricted weight-bearing for up to 6-8 weeks. During this time, physical therapy emphasizing range-of-motion of the knee and strengthening activities is prescribed. A surgeon may also recommend the use of continuous passive motion (CPM) machine to improve the graft’s success. Return to light sports activities is typically allowed at approximately 6 months with return to full sports activities between 9 and 12 months following the procedure based on the recovery.
Eligibility for chondrocyte transfer
* Age: 15 to 60 years* Body mass index (BMI): less than or equal to 35* Focal articular cartilage defect down to but not through the subchondral bone on a load bearing surface of the femoral condyle * No active inflammatory or other arthritis, clinically and by X-ray* Presence of disabling pain and/or knee locking* No degenerative arthritis (osteoarthritis)* Size of defect measures less than 7 mm in depth, less than 6.0 cm in length, and area ranging from 1.6 to 10 sq cm* Stable knee with intact meniscus and normal joint space on X-ray
(The writer is a joint replacement surgeon)