New technique for preparing cartilage for intracordal injection: the freezing and grinding method.

Objectives/hypothesis: We developed a technique for preparing harvested cartilage that creates finer, more uniform pieces by freezing with liquid nitrogen and grinding with a mortar and pestle. Herein, we report the application of this new technique for intracordal cartilage injection.

Study Design: Experimental study.

Methods: Human cartilage was obtained from surgical cases. In the standard method, harvested cartilage was prepared with scissors and a knife. In the experimental group, harvested cartilage was frozen with liquid nitrogen and ground with a mortar and pestle.

Results: It took an average of 60 minutes to manipulate cartilage using the standard technique, whereas it took an average of 10 minutes using the freezing and grinding method (P<0.001). The average size of cartilage flakes generated by the standard and new techniques were 727 and 48.6 μm, respectively. The cartilage flakes produced using scissors and a knife were able to pass through a 19-gauge needle, whereas those created using the freezing and grinding method were able to pass through a 24-gauge needle.

Conclusions: Using the freezing and grinding method, cartilage was broken into fine, uniform pieces that could pass through a 24-gauge needle. This new technique will facilitate the production of commercial cartilage material for intracordal injection.