LOCAL INJECTION OF HUMAN DENTAL PULP STEM CELLS FOR TREATMENT OF JUVENILE AVASCULAR NECROSIS OF THE FEMORAL HEAD: PRELIMINARY RESULTS IN IMMATURE PIGS

INJEÇÃO LOCAL DE CÉLULAS TRONCO DE POLPA DENTÁRIA HUMANA PARA TRATAMENTO DA NECROSE AVASCULAR JUVENIL DA CABEÇA FEMORAL: RESULTADOS PRELIMINARES EM PORCOS IMATUROS

ABSTRACT

Introduction:  Legg-Calvé-Perthes disease is a major cause of hip joint deformities in children. Currently, experimental research is directed at investigating biological therapies, including the use of human dental pulp stem cells (hDPSC), which have not yet been studied for this purpose in swine models. This study aimed to evaluate whether local injection of hDPSC induces bone mineralization in the proximal femoral epiphysis in an experimental model of avascular necrosis of the femoral head in immature pigs.

Methods:  Ten immature pigs underwent surgery to induce osteonecrosis of the proximal femoral epiphysis on the right side. In the intervention group (IG), hDPSC injections were performed immediately after osteonecrosis induction, and in the control group (CG), no additional procedure was performed. Left hips were used as controls. After 8 weeks, all animals were euthanized, and macroscopic, radiographic, and histological evaluations were performed.

Results:  Bone mineralization was greater in the right hips of the IG compared to the CG (p = 0.0356), with an average mineralization index increase of 77.78% after hDPSC injection. Radiographic evaluation of the epiphyseal index showed a greater collapse in the right IG hips compared to the right CG hips (p < 0.001) and macroscopic evaluation showed a higher chance of the femoral head being flat (p = 0,049).

Conclusion:  The injection of hDPSC into the proximal femoral epiphysis with induced osteonecrosis increases bone mineralization in immature pigs, but these treated hips show more deformity compared to the untreated hips. Level of Evidence IV, Case Series .

Keywords:
Legg-Calvé-Perthes Disease. Ischemia. Models; Animal. Swine. Dental Pulp. Stem Cells. Biological Treatment