The defective zone is prepared using a curette. In this procedure, the area is cleaned down to the sub-chondral bone using debridement. Depending on the defect, a geometrical (rectangular, triangular or trapezoidal) form is prepared, which ensures that the graft has optimum primary stability.
It is advisable to remove all the damaged cartilage tissue. If the area to be treated is very deep, two grafts can be placed on top of each other. For even deeper defects, the sub-chondral bone can be built up with spongiosa, and the chondrocyte graft applied (Fig. 5).
The prepared area is measured and BioSeed®-C is cut to the right size (Fig. 6-7).
For the fixation of BioSeed®-C different methods are available:
- fibrin glue
- cartilage suture
- transosseous anchoring with knots
- bioresorbierbare Nägel (z.B. SmartNail™)
For treating large defects or defects without marginal cartilage, the graft should be fixed in a stable and secure manner. The fixation technique using bioresorbable nails is recommended for this procedure (Fig. 8-9).
This technique can be carried out by arthroscopy or arthrotomy. It comprises 1.5 cm deep holes with cone-headed Kirschner wires (Ø 1. 5 mm) to prepare the nail introduction site. Nails (Fig. 8) must be introduced into the graft perpendicularly to the defect using a surgical hammer.