Indications which may be subjected to excessive impacts or stresses; segmental defects; fractures of the growth plate; significant impairment proximal to the graft site; metabolic or systemic disorders that affect bone or wound healing; when stabilization of fracture is not possible; where intraoperative soft tissue coverage is not planned or possible; infected sites. Severe vascular or neurological disease. Uncontrolled diabetes. Severe degenerative bone disease. Uncooperative patients who will not or cannot follow post-op instructions, including those who abuse drugs &/or alcohol. Hypercalcemia. History of or active Pott's disease. Renal compromised patients. Pregnancy.