Cartilage helps a joint glide smoothly and acts as a cushion between bony structures. But as we age, it’s vulnerable to wear and tear, or it can be damaged due to an injury. This deterioration process is called osteoarthritis.
Cartilage transplants can help reduce pain and increase function by restoring the joint’s natural anatomy. At the same time, the procedure may slow the progression of osteoarthritis and help patients delay the need for a more invasive procedure, particularly those considered too young to undergo total joint replacement.
Advances in preserving donor tissue as well as the technique and tools used to place newly grown or donor cartilage have greatly improved in the last several years, making the outcome of this course of treatment more predictable.
Most commonly performed in the knee, cartilage transplantation may also benefit patients with early joint damage in the shoulder, elbow and ankle. These procedures are not intended for patients who have been told they have bone-on-bone arthritis or if they have been told they need a joint replacement.
Factors that affect the success of these procedures include age (ideally under 45 years) and prior surgical history. These are complex situations that require careful consideration of both patient factors as well as issues specific to the knee itself.
Osteochondral Autograft Transplantation
In some cases, a patient’s own cartilage may be harvested and transferred from one part of the joint to another during a single procedure. The surgeon will remove a small piece of healthy cartilage and bone, typically from a non-weight-bearing area of the joint. The graft will then be used to plug, or fill in, the area of reduced cartilage.
Osteochondral Allograft Transplantation
Just like an organ, such as a heart or kidney, cartilage can also be donated. When donor cartilage is used, the surgeon shapes the graft to fit precisely into the patient’s area of reduced cartilage and underlying damaged bone, creating a smoother and more natural surface. This procedure is well suited for active individuals or those who have failed other cartilage procedures.
Autologous Chondrocyte Implantation
This is a two-stage procedure that requires the harvest of cartilage from a patient’s knee during an initial staging procedure. Subsequently, the cells are grown in a lab where they can later be implanted during a second surgical procedure. This procedure is typically utilized for cartilage defects in the patellofemoral joint (behind the knee cap) or in young patients who have lost areas of the cartilage surface with relatively normal underlying bone.
For patients who have had the meniscus completely removed in a previous surgery, a meniscus transplant can be an option. Using this technique, surgeons transplant size-matched, donated meniscus cartilage which has been tested to ensure that it is free of any transmittable disease. Unlike other forms of tissue transplantation, this procedure does not require patients to be on medication to prevent tissue rejection.
To replace meniscus cartilage, surgeons can arthroscopically, through small incisions, sew in a meniscus transplant that heals and functions much like the patient’s own meniscus. This leads to a more stable and less painful knee that might otherwise have developed progressive arthritis.