Which patients are suitable for knee cartilage cell transplantation?
Criteria for a viable patient for ACT
- Articular defect 2.5 - 10 cm² size
- Intact meniscus
- Physiological axis - no misalignment
- Free range of motion
- Intact ligaments in knee
Cartilage transplantation is not advisable for all patients. Ideally patients are between 15 and 55 years of age, although this is flexible.
If fitness and the general level of health is good, active people up to the age of 65 years have successfully received cartilage transplants and have gone on to enjoy sports such as skiing once more.
The following factors are more likely to be a barrier to successful transplants than the age of the patient:
- The patient is overweight (excess weight puts strain on joints)
Solution: presurgery weight control. - Malalignment of the bones in the leg eg. bow leggedness.
Solution: malalignment can be addressed by osteotomy during the same surgical appointment as cartilage transplant. - Joint surfaces opposite the area of damaged cartilage are also rough (often as a result of trauma), in this case a metal implant (Repicci inlay) has to be fitted.
- There is a genetically determined weakness in the cartilage tissue.
Solution: partial or full prosthesis. - Instability of the knee due to damaged ligaments.
Solution: ligaments must be reconstructed e.g. by ACL reconstruction - Instability of the knee due to missing or severely damaged meniscus.
Solution: A Repicci inlay might be preferable. - The area of the cartilage defect is too large (greater than 10 cm).
Solution: the surgeon may recommend a joint preserving Repicci inlay. - Due to another medical condition or very old age a quick recovery (weight bearing) time is important.
Solution: in this case a Repicci inlay might be more suitable due to the possibility of full weight bearing on the day after surgery.
A thorough evaluation of suitability is important for a good long term cartilage cell transplant result.
Sometimes younger patients have to be excluded following examination, particularly when a Repicci inlay or (partial knee replacement) is considered to be a better recommendation for long term joint preservation.
Prof. Dr. med. Sven Ostermeier, Consultant for Orthopaedic Knee Surgery
