Treatment concept
Using a minimally invasive key-hole technique (arthroscopy), a small amount of cartilage cells (chondroblasts) is removed from a healthy, low-density cartilage area (around 250 milligrams) and cultivated in a nutrient solution (this can be either patient blood or an artificial alternative) in the laboratory. After about two to six weeks, the cells have multiplied to the extent that they can be introduced into the defective cartilage region. Therefore, 2 surgical procedures are usually necessary.
To ensure that the cells (which are in a solution) remain in place, they are injected under a membrane that has been sutured so finely over the cartilage defect that the suture is waterproof. This membrane can either be the patient’s own periosteum (also called periosteum, e.g. from the shin), or it can be replaced by a layer of connective tissue (collagen) from the pig or an artificial membrane. Some providers also attach the cartilage cells to collagen in the laboratory. Now there are many well-fed, endogenous cartilage cells in the area of the cartilage damage, which can significantly promote cartilage healing.
Field of application
Autologous cartilage transplantation is increasingly used for cartilage defects in the knee joint, especially to prevent the development of secondary arthrosis. Large cartilage defects, or smaller defects that have already been unsuccessfully treated elsewhere, are one of the main indications for autologous cartilage transplantation. In these cases, autologous cartilage transplantation is usually covered by the health insurance in Germany.
Alternatives
Alternatives to autologous cartilage transplantation are primarily a larger-area cartilage transplantation, in which a larger amount of cartilage tissue is introduced directly into the defect from a slightly loaded part of the joint, as well as various techniques within the framework of arthroscopy, which, by actively placing micro-injuries through small drill holes or by scraping, cause localized bleeding and initiate healing processes or smooth the damaged joint surface (so-called joint lavage or abrasion). Other surgical procedures such as joint replacement (endoprosthesis), joint stiffening (arthrodesis) or joint repositioning (corrective osteotomy) cannot be performed by means of arthroscopy, but require an open and thus larger operation with correspondingly higher risks and longer recovery time, but may still be the better choice under certain circumstances.Of course, omitting an intervention as well as a merely symptomatic treatment (e.g. with painkillers) are always alternatives that have to be considered carefully, especially if the risks always associated with an intervention are significantly increased by concomitant diseases or age, or if the chances of success are significantly reduced. Which decision to act (or not to act) is the best choice in an individual case – i.e. the one with the best ratio of risks and chances of recovery – depends on many factors such as concomitant diseases, age, joint malpositions, anatomical deviations from the norm, etc.
Irrespective of the therapeutic decision, the success of the therapy can never be guaranteed; the success or failure of the treatment is always random. Conversely, a failure or even the occurrence of serious complications does not automatically mean that the wrong treatment was chosen or that mistakes were made in its implementation. Like any operation, autologous cartilage transplantation also involves risks.
While scars and pain are to be expected regularly as a result of the surgical incisions, as well as minor bleeding during and after the operation, there are also more serious complications, which are very unlikely if the procedure is carried out properly, but can never be completely ruled out. These are particularly severe bleeding during or after the operation, which in the worst case also requires a blood transfusion with all its risks such as an immune reaction (which in the worst case can lead to shock and death) or infection. Injuries to surrounding tissues such as nerves and vessels or to the joint itself are also possible and can ultimately mean a new operation or permanent damage.
Despite working under sterile conditions, an infection of the operated region cannot always be prevented. In the worst conceivable scenario, it can develop into life-threatening sepsis or require stiffening of the joint. Likewise, allergic reactions to materials used during surgery or life-threatening complications caused by anesthesia are very rare but possible.
Furthermore, the success of the treatment can never be guaranteed one hundred percent. Despite these risks, the surgery required for autologous cartilage transplantation is a standard procedure, and the more serious complications listed above are very rare. Concerns are particularly appropriate if concomitant diseases are present or suspected, such as those affecting blood coagulation, the immune system, wound healing or cartilage metabolism, thereby increasing the risks of the procedure.
A reduced general condition or cardiovascular weakness due to previous illnesses or age can also increase the general anaesthetic and surgical risks. Weighing up the risks and chances of recovery when comparing treatment options is essential in each individual case and is not always easy. Patients should consider seeking more than just medical advice in their personal decision-making process. As with any upcoming operation, it is helpful for a broader assessment of the personal health situation and its optimal treatment to consult a specialist who can either carry out the operation himself (or have it carried out in his institution) or not.
