The invention provides instruments and methods for prophylactic treatment of an osteoporotic vertebral body or for treating a vertebral compression fracture (VCF). In one exemplary method, a probe system uses a high speed rotational elastomeric cutter having an optional expandable abrasive surface for abrading or cutting at least one path or region within vertebral cancellous bone. Irrigation and aspiration sources are included in the probe system for removing abraded bone debris. In one embodiment, the high speed rotational abrader uses a tissue-selective abrading surface that abrades or cuts bone but does not cut soft tissue. In another embodiment, an expandable abrading surface allows the treatment of bone with low pressures to create paths or spaces without explosive expansion forces known in prior art balloon procedures that are designed to crush and compact cancellous bone in a vertebra. After the creation of a path or space, an in-situ hardenable bone cement volume is introduced into each path or space to support the vertebra.