An apparatus comprising: an elongated anatomical support member; two buttressing members (12d, 12e), wherein said buttressing members (12d, 12e) and said elongated anatomical support member comprise at least one layer of laminar sheeting, and wherein said buttressing members (12d, 12e) are engaged with respective sides of said elongated anatomical support member, and wherein said buttressing members (12d, 12e) are further configured to resist lateral flexing of at least a portion of said elongated anatomical support member on the sides where said buttressing members (12d, 12e) are engaged with said elongated anatomical support member such that normal anatomic loading forces in the direction of gravity put upon said anatomic support member are not transmitted to said buttressing members (12d, 12e), and in which said resisting of lateral flexing of said elongated anatomical support member is perpendicular to the plane formed by said laminar sheeting of said elongated anatomical support member; a radiolucent rotatable joint formed by engaging said buttressing members (12d, 12e) and said elongated anatomical support member with turntable bearings (12x, 12y) and two lateral supports (12f, 12ee) thereby providing a fixed axis for rotation of the said elongated anatomical support member in the plane formed by said laminar sheeting of said elongated anatomical support member; and, at least a portion of said laminar sheeting of said elongated anatomical support member proximal to said fixed axis is configured to be substantially perpendicular to said fixed axis, yet substantially parallel to said buttressing members (12d, 12e), and at least a portion of said laminar sheeting and said buttressing members are substantially artifact-free and formed of material/(s) that does/do not cause substantial radiographic or nuclear imaging artifacts when medically imaged thereby, and in which said substantially artifact-free portion of said laminar sheeting of said radiolucent rotatable joint is configured to engage with said turntable bearings (12x, 12y) thereby forming a buttressed rotatable joint apparatus. an elongated anatomical support member; two buttressing members (12d, 12e), wherein said buttressing members (12d, 12e) and said elongated anatomical support member comprise at least one layer of laminar sheeting, and wherein said buttressing members (12d, 12e) are engaged with respective sides of said elongated anatomical support member, and wherein said buttressing members (12d, 12e) are further configured to resist lateral flexing of at least a portion of said elongated anatomical support member on the sides where said buttressing members (12d, 12e) are engaged with said elongated anatomical support member such that normal anatomic loading forces in the direction of gravity put upon said anatomic support member are not transmitted to said buttressing members (12d, 12e), and in which said resisting of lateral flexing of said elongated anatomical support member is perpendicular to the plane formed by said laminar sheeting of said elongated anatomical support member; a radiolucent rotatable joint formed by engaging said buttressing members (12d, 12e) and said elongated anatomical support member with turntable bearings (12x, 12y) and two lateral supports (12f, 12ee) thereby providing a fixed axis for rotation of the said elongated anatomical support member in the plane formed by said laminar sheeting of said elongated anatomical support member; and, at least a portion of said laminar sheeting of said elongated anatomical support member proximal to said fixed axis is configured to be substantially perpendicular to said fixed axis, yet substantially parallel to said buttressing members (12d, 12e), and at least a portion of said laminar sheeting and said buttressing members are substantially artifact-free and formed of material/(s) that does/do not cause substantial radiographic or nuclear imaging artifacts when medically imaged thereby, and in which said substantially artifact-free portion of said laminar sheeting of said radiolucent rotatable joint is configured to engage with said turntable bearings (12x, 12y) thereby forming a buttressed rotatable joint apparatus.