Non-unions occur mostly due to fracture stability, decrease in blood supply,
or both. The cause of non-union is subcategorised into biological and mechanical
factors. There are several risk factors for non-union which include -but are not limited
to smoking, diabetes mellitus, infection, open or compound fractures, senility,
inadequate nutrition and some drugs like NSAIDs.
Mechanical factors include the application of electric fields, physical stimulation and
ultrasound. The biological materials include osteoconductive agents such as tricalcium
phosphate (TCP), hydroxyapatite (HA) preferably with added Osteoinductive agents,
which enhance migration, proliferation and differentiation of cells to promote fracture
healing. Such agents as Platelets rich plasma (PRP), Bone marrow aspirate concentrate
(BMAC), and Bone morphogenetic protein (BMP).
Keywords: Bone defects, Bone Marrow Aspirate Concentrate (BMAC), Delayed
union, Expanded stem cells, Fracture, Malunion, MSCs, Non-union.