Femoral head resurfacing apparatus and methods
OwnerRobert Evansinventor
Life of this patent
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Abstract
A femoral head resurfacing apparatus includes a cap of hemispherical shape and stabilization structure (e.g., one or more non-shear fixation bars) that inserts into slots cut into the femoral head, so that the cap remains substantially immovable other than due northerly. A method of resurfacing the femoral head of a hip joint includes removing longitudinal slots or holes of bone in the femoral head, and attaching a hemispherical cap to the head, the cap having non-shear fixation bars or other stabilizing structure for mating engagement with the slots or holes.
Claims18
Femoral head resurfacing apparatus, comprising
- (a) a cap having a substantially hemispherical shape of substantially uniform thickness;
- and
- (b) a plurality of non-shear fixation bars, the non-shear fixation bars comprising a plurality of gear shaped teeth to encourage bone ingrowth between the teeth, an equatorial end of each non-shear fixation bar forming a hole configured to accept a screw for attaching mounting hardware to couple the cap with the femoral head.
Femoral head resurfacing apparatus, comprising
- (a) a cap having a substantially hemispherical shape of substantially uniform thickness, the cap configured to interface with a metal cup socket maintaining a clearance tolerance of 0.01 mm;
- and
- (b) a plurality of non-shear fixation bars for insertion into respective longitudinal slots cut into the femoral head, an equatorial end of each non-shear fixation bar forming a hole configured to accept a screw for attaching mounting hardware to couple the cap with the femoral head.
Femoral head resurfacing apparatus, comprising
- (a) a cap having a substantially hemispherical shape of substantially uniform thickness;
- the cap being fixed by a plurality of metal spring loaded absorption fixators, each fixator being screwed into the cap and femoral head, to prevent loosening of the cap and
- (b) a plurality of non-shear fixation bars for insertion into respective longitudinal slots cut into the femoral head, wherein the cap remains substantially immovable other than due northerly.
A method of resurfacing the femoral head of a hip joint, comprising the steps of:
- removing a plurality of longitudinal slots of bone in the femoral head;
- and
- attaching a hemispherical cap to the head, the cap forming a plurality of non-shear fixation bars for mating engagement with the slots.
A femoral head resurfacing cap, comprising:
- a hollow cap to mate with a plurality of longitudinal slots within a femoral head of the hip joint, the cap forming non-shear bars for mating engagement with the slots;
- and
- a plurality of spring-loaded absorption fixators for attaching the cap to the head.
A method for capping a femoral head with a shell, comprising the steps of:
- inserting a centering device in a centering hole of the femoral head;
- drilling a plurality of holes about the centering hole, a diameter of the holes being from between about 3 mm to 12 mm, a depth of the holes being about 6 mm;
- and
- inserting fin-like dowels, which are a part of a centering hole post, into the holes to prevent migration of the shell.
Dependencies are inferred from the claim text.