NOVELTY - The test probe (100) is inserted through periosteum and/or soft tissue on a bone, such that the test probe contacts the bone. The test probe is inserted multiple times into same location of the bone, to create one or more microscopic fractures in the bone for evaluating the resistance of the bone to microscopic fracture. USE - For assessing risk of bone fracture of human and animal. ADVANTAGE - The diagnostic instrument directly determines indications of fracture risk through microcrack inducement, to enable multitudes of patients at risk to receive preventative therapy before suffering a fracture. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) diagnostic instrument for assessing bone fracture risk; (2) test instrument for determining properties of bone; and (3) combination of test probe and reference probe for diagnostic instrument.