Using Mesenchymal Stem Cells to Fill Bone Void Defects in Patients With Benign Bone Lesions

Orthobiologics have recently become a mainstay in treating bony defects whether related to trauma, tumor, or other various reconstructive entities.1 Historically, benign bone growths that were excised, would be filled with either cement, autograft bone, or allograft substances. More recently, other substances have been utilized. These substances carry any or all osteoinductive, osteoconductive, or osteogenic properties. Various materials have been used to fill bony voids specifically related to benign bone growths. Trinity™ by Blackstone Medical inc. is an allograft substance that has recently began utilization. The difference in Trinity compared to various other allografts is that it utilizes mesenchymal stem cells (MSC) along with an allograft carrier to incorporate and induce bone formation. Previously, in order for stem cells to be included in grafting, it would require bone marrow aspiration and the morbidity that is associated with iliac crest bone grafting. Trinity MSC's are pre-immunodepleted and therefore, do not stimulate local T-cell proliferation but instead are activated to act as osteoblasts and stimulate bone formation. This local response, could accelerate healing, earlier weight-bearing, healing, and filing of bone voids in patients that have had excision of bony masses. In previous animal models, the use of MSC's have been shown to increase bone healing in critical sized defects. Trinity is currently approved for FDA use in bone defects specifically within the spine or trauma. It has not been shown to have any significant adverse events over standard bone substitute products. We hypothesize benign bone lesions that undergo curettage and filling with Trinity will heal faster than bone lesions filled with basic bone grafting.