A new resorbable bone void filler in trauma: early clinical experience and histologic evaluation

Six patients with traumatic bone injuries were treated by packing ultraporous beta-tricalcium phosphate (beta-TCP), a synthetic bone void filler, into defect sites using firm finger pressure. Radiographs showed new bone consolidating in treated sites after as little as 2 months. A biopsy obtained from a fractured calcaneus 9 months after surgery showed new bone growing within the ultraporous scaffold. Regions of newly mineralized bone and woven bone in the scaffold suggested that the defect site was undergoing repair. Some new bone had developed lamellar architecture. Higher radiodensity and slower resorption of ultraporous bone void filler in this human case, relative to that seen in a canine study, is attributed to slower metabolism in humans relative to dogs and to greater packing pressures used in the clinic. The histology specimen did not indicate untoward inflammatory response or significant foreign body reaction. Thus, this first human histology report supports the use of biocompatible ultraporous beta-TCP to enhance new bone formation in bone defects.