Augmentation of bone healing of nonunion fracture using stem cell based tissue engineering in a dog: a case report.

A 4-year-old, intact male crossbreed dog, weighing 27 kg, was referred for the treatment of a nonun- ion fracture. The radiographs revealed displacement of the radius and ulna bone fracture fragment and a sclerotic fracture end of the radius. Autologous adipose derived stem cells (ADSCs) were isolated and expanded ex vivo in a culture. The ADSCs (3.2 × 107 cells) were seeded on a composition scaffold made from hydroxyapatite (HA) and chitosan (CH) fibers. The seeded scaffold with ADSCs was placed on the fracture site and the bone fracture was stabilized. A sample of seeded scaffold with ADSCs was taken to evaluate the extent of cell attachment and morphology on the scaffold using scanning electron microscopy (SEM). SEM showed that ADSCs adhered to the scaffold well and many bone nodules formed from the bone matrix secreted by ADSCs. Three months after surgery, the nonunion had successfully healed with no complications. The application of a composition scaffold of HA and CH containing ADSCs can be used to treat a nonunion fracture by augmenting bone healing and may decrease the risk of surgical failure of nonunion fractures.