SyCaP: A synthetic non-degrading, non-drug releasing cartilage implant
Cartilage defects are found in 63% of arthroscopic procedures, often in middle-aged patients. Operations to restore the cartilage are often unsuccessful and provide little benefit to patients in this age range. Currently metal implants are the method of choice for the treatment of these defects. However, since the biomechanical properties of these metal implants do not correspond to those of cartilage, these implants cause a gradual increase in the amount of cartilage damage in the surrounding tissue. In addition to this, when metal implants are used MRI diagnostics can no longer be used to visualise and monitor the wound area. The aim of this project is to develop a non-resorbable implant for the treatment of cartilage defects. The biomechanical properties of the implant will be tailored to match the natural tissue and will lead to improved healing and a better clinical outcome compared to the current metal implants. Unlike the metal implants, the solutions developed here will still allow the use of non-invasive MRI imaging to monitor the healing progress.
Project status 2016-2017
The first 12 months of this project have resulted in the development of various designs. These were created and experimentally evaluated for initial fixation during implantation and for their ability to preserve healthy environmental cartilage from wearing. In addition, various types of coatings were evaluated for the likelihood that they would stimulate bone ingrowth and therewith ensure long-term fixation.
All this work has resulted in the selection of viable prototypes and a promising coating method for stimulating long-term bone integration. Molds were developed to create these designs for testing in a goat study, and surgical tools were designed for appropriate implantation of the implants in these goats.
Finally, a short-term in vivo study was started for the first evaluations of the new implant. We are currently looking forward to obtaining the first results from this in vivo study, which should then lead to improvements in the design of the implant before a final long-term in vivo trial is run at the end of the project.
Project Status 2017-2018
In 2017, a short-term study was performed on the integration of our implant with the bone. Based on this highly valuable study, the SyCap team was able to select the most promising designs for further development. Subsequently, we were able to use the results to significantly improve the implants on three separate aspects: the design, the mechanical properties of the materials that make contact to bone, and the coatings that stimulate osseointegration. We implemented all these changes as planned, and tested and documented all innovations extensively. This was a major achievement.
Based on the encouraging developments, we have decided to adjust and extend the original project, mainly to include an additional short-term study to proof the superior osseo- integration performance of the current design. The next step in the project is to run a new short-term study in the first half of 2018. If the osseointegration results are as anticipated, we’ll proceed to the final long-term trial in Q4, to demonstrate that the implant is able to stop the progression of osteoarthritis in patients with isolated cartilage defects.
René van Donkelaar, PhD
Eindhoven University of Technology