System and Method for Replacing Degenerated Spinal Disks

An artificial spinal disk adapted to be positioned between adjacent vertebrae of a spine, comprising:

• a first portion, including:
• a first upper plate;
• a first lower plate positioned opposite the first upper plate such that a gap having a maximum width exists between the first lower plate and the first upper plate;
• a first device that can urge the first upper and first lower plates apart;
• and
• wherein when the first upper plate and the first lower plate are urged together, the gap between a portion of each of the first upper plate and the first lower plate narrows, such that the gap between a remaining portion of each of the first upper plate and the first lower plate is no wider than the maximum width;
• a second portion, including:
• a second upper plate;
• a second lower plate positioned opposite the second upper plate such that a gap having a maximum width exists between the second lower plate and the second upper plate;
• a second device that can urge the second upper and second lower plates apart;
• wherein when the second upper plate and the second lower plate are urged together, the gap between a portion of each of the second upper plate and the second lower plate narrows, such that the gap between a remaining portion of each of the second upper plate and the second lower plate is no wider than the maximum width;
• a device that can join the first portion with the second portion.

A artificial spinal disk for substituting at least a portion of a spinal disk between adjacent vertebrae, comprising:

• an upper housing adapted to be positioned adjacent to a first vertebra;
• a lower housing positioned opposite the upper housing, the lower housing adapted to be positioned adjacent to a second vertebra;
• an first spacer positioned between the upper housing and the lower housing;
• a second spacer positioned between the upper housing and the lower housing;
• wherein the first spacer and the second spacer urge a gap between the upper housing and the lower housing;
• a shaft;
• the first spacer and the second spacer mounted on the shaft, one or both of the first spacer and the second spacer being movable along the shaft;
• a resisting mechanism adapted to urge the first and second spacer apart;
• and
• wherein when a force is applied to the upper housing and the lower housing such that the resisting mechanism is overcome, the gap is reduced;
• a latch mechanism on at least one of the upper housing and the lower housing;
• a receiving mechanism that can receive the latch mechanism on at least the other of the upper housing and the lower housing;
• and
• wherein the latch mechanism prevents the upper and lower housing from expanding beyond a desired distance.

An artificial replacement disk that is positionable between vertebrae comprising:

• a first housing including a first cavity and a second cavity;
• a second housing including a third cavity and a fourth cavity;
• wherein the first cavity and the third cavities are aligned with each other and are provide along an anterior/posterior line relative to a spine when the disk is implanted in a spine;
• wherein the second cavity and the fourth cavities are aligned with each other and are provide along an anterior/posterior line relative to a spine when the disk is implanted in a spine;
• a first spacer and a second spacer, said first and second spacers mounted on a first shaft with a first resisting member located between the first and the second spacers, which first resisting member can urge said first and second spacers apart;
• and
• said first and second spacers partially located in said first cavity and partially located in said second cavity;
• a third spacer and a fourth spacer, said third and fourth spacers mounted on a second shaft with a second resisting member located between the first and the second spacers, which second resisting member can urge said third and fourth spacers apart;
• and
• said third and fourth spacers partially located in said third cavity and partially located in said fourth cavity;
• and
• when the first housing is urged toward the second housing at least one of the first and the second spacers move relative to each other and against the first resisting member and the third and fourth spaces move relative to each other and against the second resisting member.

An artificial replacement disk that is positionable between vertebrae comprising:

• an upper housing including an upper cavity;
• a lower housing including a lower cavity;
• a first spacer and a second spacer, said first and second spacers mounted on a shaft with a resisting member located between the first and the second spacers, which resisting member can urge said first and second spacers apart;
• and
• said first and second spacers partially located in said upper cavity and partially located in said lower cavity.

An artificial replacement disk that is positionable between vertebrae comprising:

• an upper housing including an upper cavity;
• a lower housing including a lower cavity;
• a first spacer and a second spacer, said first and second spacers mounted on a shaft with a resisting member located between the first and the second spacers, which resisting member can urge said first and second spacers apart;
• and
• said first and second spacers partially located in said upper cavity and partially located in said lower cavity;
• and
• wherein the first and second spacers are oval in cross-section.

An artificial replacement disk that is positionable between vertebrae comprising:

• an upper housing including an upper cavity;
• a lower housing including a lower cavity;
• a first spacer and a second spacer, said first and second spacers mounted on a shaft with a resisting member located between the first and the second spacers, which resisting member can urge said first and second spacers apart;
• and
• said first and second spacers partially located in said upper cavity and partially located in said lower cavity;
• and
• wherein the first and second spacers are elliptical in cross-section.