An experimental investigation into the correlation between the diameter of reimplanted cartilage blocks and efficacy of cartilage regeneration after auricular reconstruction.

Abstract

Preventing thoracic deformities during auricular reconstruction is a challenge for surgeons who utilize multiple costal cartilage grafts to fabricate a 3-dimensional framework. Reimplantation of cartilage blocks reduces thoracic deformities, but there is no consensus on how to maximize the effectiveness of reimplantation. We aimed to investigate the correlation between the block diameter and the efficacy of cartilage regeneration at the donor site in a rabbit model. Seventy-two rabbits were randomly placed into 6 groups: those with reimplanted cartilage blocks with a diameter of (1) 0.7 mm, (2) 0.6 mm, (3) 0.5 mm, (4) 0.4 mm, (5) 0.3 mm, and (6) the control group. Cartilage blocks of various diameters were shredded and returned to the perichondrial pocket at the donor site. The efficacy of promoting biomechanical strength, cartilage tissue growth, activation of chondrocyte proliferation, and stimulation of cartilage-specific extracellular matrix secretion was assessed. The diameter of the implanted cartilage block was a highly correlated factor during regeneration. Smaller diameters with appropriate interstitial spaces between blocks promoted better cartilage tissue growth, chondrocyte proliferation, and extracellular matrix secretion. According to our findings, 0.4 mm is the maximum diameter for achieving the best regeneration performance (range, 0.3-0.7 mm).