Purpose / Introduction: To date, there are no satisfactory solutions to the meniscal originated knee
pain post meniscal tear repair. In this study a newly developed polyurethane material that has the
intended properties of reducing pain and inducing tissue growth in a damaged meniscus is tested.
Materials and Methods: All patients will be imaged using conventional and dynamic MR imaging
techniques at 1 week and 3, 12 and 24 months after surgery.
The influx of gadolinium contrast in a tissue during the first three minutes after injection gives a
measure of the vascularisation, capillary permeability, perfusion and composition of the interstitial
fluid. It can be measured using dynamic MRI and is represented as a Time Intensity Curve (TIC). This
curve permits an evaluation of the healing process after surgery.
Discussion / Conclusion: Thus far 11 patients have received meniscal implants. Eight medial and three
lateral menisci were operated. All implants covered the posterior horn with 3 reaching halfway into the
meniscal body and one extending into the anterior horn. The average length of the scaffold meniscus
measured on MR imaging was 45mm.
In the first week after surgery, the capsule and suture area display fast and intense enhancement typical
for post-operative inflammation and the formation of early scar-tissue. There is no enhancement in the
base or the tip of the scaffold meniscus. After three months the speed and intensity of enhancement in
the capsule and suture area between the remnants of the native meniscus and the scaffold have
decreased indicating maturation of scar-tissue. However, the base of the scaffold meniscus now shows
enhancement. This can only be explained by proliferation of blood vessels from the capsule and theresidual meniscus wall into the scaffold meniscus. The tip of the matrix shows limited enhancement in
some patients after three months.
On anatomical MR images, the signal intensity (SI) of the implanted scaffold is close to that of water
on both T1- and T2-weighted spin echo and turbo spin echo sequences in the first week. After three
months the SI decreases but is still clearly higher than that of the native meniscus. The implants in the
posterior horn all had a normal position and no loosening of the sutures or tears of the scaffold were
found. After three months, one of the patients had slight expulsion of body of the scaffold meniscus but
this is a common finding in transplanted menisci
