Purpose
To compare five different one-step treatments for a single patella full-thickness
cartilage lesion in an animal model (New Zealand rabbits).
Methods
Pre-clinical randomized controlled trial in 20 New Zealand white rabbits and 40 knees
with five different type of treatments:
1. Control group (debridement, natural history)
2. Nanofractures (1 mm)
3. Nanofractures plus fibrin glue
4. Bone marrow aspirate
5. Autologus minced cartilage
A 4-mm full-thickness cartilage lesion was created in the patella of the rabbits through an open
approach. Every knee was randomized for a different treatment. Rabbits were fed and taken care
at the university’s vivarium. After 20-weeks of follow-up the patellae were extracted and the
cartilage was studied microscopically. The outcomes studied were the percentage of filling for
the cartilage defect and the 14 quality items from ICRS (International Cartilage Repair Society)
II.
Results
There were no statistically significant differences when comparing the five groups
together. However, the worst quality in repair was observed in the control group and the
nanofractures group. There were statistically significant differences for some variables when
comparing nanofractures head-to-head with other treatments. Nanofractures plus was better in
surface architecture, subchondral bone and mid/deep zone assessment. Bone marrow aspirate
was superior in basal integration, chondrocyte clustering and mid/deep zone assessment.
Meanwhile, minced cartilage was only superior in subchondral bone quality.
Conclusion
One-step cartilage lesion treatment for the patella with nanofractures plus fibrin
glue, bone marrow aspirate and autologous minced cartilage, were superior to traditional
nanofractures. These treatments should be studied further in pre-clinical and clinical studies as
they could be cheap, effective and easy ways of treating these types of injuries in a single
surgery.