A differential dissecting instrument (600, 3200) for differentially dissecting complex tissue comprising: a handle (610, 3212, 3412, 3820); an elongate member (620, 1410, 2620) having a first end and a second end, the first end connected to the handle; a differential dissecting member (350, 390, 630, 631, 1420, 1500, 1501, 1502, 1600, 1640, 1680, 1700, 1800, 1910, 2030, 2100, 2110, 2230, 2520, 2610, 2710, 2800, 3292, 3492, 3596, 3600, 3610, 3810, 4010) configured to be rotatably attached to the second end, the differential dissecting member comprising at least one tissue engaging surface (370, 540, 590, 850, 1010, 1520, 1620, 1690, 1710, 1810, 1910, 2009, 2034, 2111, 2232, 2860, 3503, 3660, 3690) and further comprising a three-dimensional surface having no sharp edges such that the differential dissecting member will not slice the complex tissue; and a mechanism configured to mechanically rotate the differential dissecting member around an axis of rotation thereby causing the at least one tissue engaging surface to move in at least one direction against the complex tissue, wherein the at least one tissue engaging surface is configured to selectively engage the complex tissue such that when the differential dissecting member is pressed into the complex tissue, the at least one tissue engaging surface moves across the complex tissue and the at least one tissue engaging surface disrupts at least one soft tissue in the complex tissue, but does not disrupt firm tissue in the complex tissue, and wherein the tissue engaging surface further comprises projections (375,1550, 2032) that extend outward from the tissue engaging surface, wherein the projections are configured to sweep through any gel-like material that covers tightly packed, organized arrays of fibrous components that are part of the firm tissue, the projections further configured to snag and tear loosely packed fibrous components of the soft tissue, but to slip off of, and not snag, the tightly packed, organized arrays of fibrous components in the firm tissue. a handle (610, 3212, 3412, 3820); an elongate member (620, 1410, 2620) having a first end and a second end, the first end connected to the handle; a differential dissecting member (350, 390, 630, 631, 1420, 1500, 1501, 1502, 1600, 1640, 1680, 1700, 1800, 1910, 2030, 2100, 2110, 2230, 2520, 2610, 2710, 2800, 3292, 3492, 3596, 3600, 3610, 3810, 4010) configured to be rotatably attached to the second end, the differential dissecting member comprising at least one tissue engaging surface (370, 540, 590, 850, 1010, 1520, 1620, 1690, 1710, 1810, 1910, 2009, 2034, 2111, 2232, 2860, 3503, 3660, 3690) and further comprising a three-dimensional surface having no sharp edges such that the differential dissecting member will not slice the complex tissue; and a mechanism configured to mechanically rotate the differential dissecting member around an axis of rotation thereby causing the at least one tissue engaging surface to move in at least one direction against the complex tissue, wherein the at least one tissue engaging surface is configured to selectively engage the complex tissue such that when the differential dissecting member is pressed into the complex tissue, the at least one tissue engaging surface moves across the complex tissue and the at least one tissue engaging surface disrupts at least one soft tissue in the complex tissue, but does not disrupt firm tissue in the complex tissue, and wherein the tissue engaging surface further comprises projections (375,1550, 2032) that extend outward from the tissue engaging surface, wherein the projections are configured to sweep through any gel-like material that covers tightly packed, organized arrays of fibrous components that are part of the firm tissue, the projections further configured to snag and tear loosely packed fibrous components of the soft tissue, but to slip off of, and not snag, the tightly packed, organized arrays of fibrous components in the firm tissue.