Bone marrow stimulation
Bone marrow stimulation locally is a long established method of cartilage repair in focal chondral defect. Breaking through the underlying bone (subchondral bone) one prepares minute canals for the mesenchymal stem cells to travel to the site of chondral lesion.
For small focal chondral lesions (size smaller than 2 cm2) it is the easiest and most widely used technique. The rational is that proper way must be established for the mesenchymal stem cells located in the bone marrow to pass through the bone and repair the chondral lesion. Drilling is one of the basic methods and cutting a hole with an awl is another one. Firstly a coagulum is formed at the site of the lesion that would transform into scar and finally into fibrocartilage.
The method requires 6 week partial weight bearing postoperatively (crutches) and gradual return to full weight bearing afterwards.
Fibrocartilage is formed at the site of the repair, which is of poorer quality when compared to hyaline cartilage, but it may bring acceptable relief for the patient. In the long term bone marrow stimulation is believed to deteriorate and usually other, more sophisticated technique must be utilized.
