US 6,981,989 B1
Rotatable and reversibly expandable spinal hydraulic prosthetic device
Lewis W. Fleischmann, Pikesville, Md. (US); and Christopher Galuardi, Owings Mills, Md. (US)
Assigned to X-Pantu-Flex DRD Limited Liability Company, Lutherville, Md. (US)
Filed on Apr. 22, 2003, as Appl. No. 10/419,899.
Int. Cl. A61F 2/44 (2006.01)
U.S. Cl. 623—17.11 31 Claims
OG exemplary drawing
 
1. A rotatable and reversibly expandable spinal hydraulic prosthetic device comprising:
(a) an upper crown plate member for engaging a vertebra;
(b) at least one center bearings plate member rotationally coupled to said upper crown plate member;
(c) a lower crown plate member for engaging a vertebra, coupled to said center bearing plate member;
(d) at least one reversibly displaceable bellows member having a fluid contained therein and sandwiched between said lower crown plate member and said center bearings plate member for resisting shearing force loads between said upper crown plate member and said lower crown plate member; and,
(e) a dashpot mechanism interposed between said center bearings plate and said lower crown plate member for dampening shock loads.