Cement restrictor for total hip operations

Claim 2

A cement restrictor device adapted for use in a hip replacement operation, which device comprises: a raised cap-like upper element defining a cavity therein, the upper element having a continuous solid upper surface, the lower edge of the element adjoined to a peripheral lid element extending outwardly from the lower edge thereof, the lower crown portion of the cap-like element generally adjacent to the adjoinment to the lid element characterized by a plurality of peripheral passages therein to permit the passage of a cement material therethrough, whereby the upper element may be inserted into a hole in a bone of about the size of the upper element and cement applied to the interior cavity and forced through the passageway so as to lock the device between the lid element and the cement into the hole in the bone.

Claim 3

The device of claim 1 wherein the upper cap-like element is a hemispherical dome-like element.

Claim 4

The device of claim 1 wherein the device comprises a polymeric material of olefinic resin or nylon.

Claim 5

The device of claim 1 wherein the passageways are generally equally spaced about the periphery and the number of passageways ranges from about 5 to 15.

Claim 6

The device of claim 1 wherein the diameter of the cavity is about one-half the diameter of the lid element.

Claim 7

The device of claim 1 wherein the passageways comprise a plurality of slots about the periphery.

Claim 8

A cement restrictor device adapted for use in an operation to lock the device into a hole in a bone, which device comprises: a hemispherical dome-like raised upper element defining a cavity therein, the upper element having a continuous solid upper surface, the lower edge of the upper element adjoined to a peripheral flat lid element extending outwardly from the lower edge thereof, the lower crown portion of the upper element generally adjacent to the lid element characterized by a plurality of equally spaced slot passageways therein to permit the passage of cement therethrough, the device composed entirely of a medically acceptable polymeric material, whereby the dome-like element may be inserted into a hole in a pelvic bone, cement applied to the cavity and forced through the slot passageways and hardened to lock the device into the hole between the hardened beads of cement and the lid element.

Claim 9

A cement restrictor device adapted for use in an operation to lock the device into a hole in a bone, which device comprises: a hemispherical dome-like raised upper element defining a cavity therein, the upper element having a continuous solid upper surface, the lower edge of the upper element adjoined to a peripheral flat lid element extending outwardly from the lower edge thereof, the lower crown portion of the upper element generally adjacent to the lid element characterized by a plurality of equally spaced slot passageways therein to permit the passage of cement therethrough, the device composed entirely of a medically acceptable polymeric material, whereby the dome-like element may be inserted into a hole in a pelvic bone, cement applied to the cavity and forced through the slot passageways and hardened to lock the device into the hole between the hardened beads of cement and the lid element.

Claim 10

In a method of replacing a diseased or damaged hip which comprises: a. reaming a cavity into the pelvic bone of a patient; b. drilling a plurality of holes into the bone to provide a means to anchor a socket element therein by the use of a hardenable cement; c. inserting in the holes a cement restrictor device which comprises a raised cap-like upper element defining a cavity therein, the upper element having a continuous solid upper surface, the lower edge of the element adjoined to a peripheral lid element extending outwardly from the lower edge thereof, the lower crown portion of the cap-like element generally adjacent to the adjoinment to the lid element characterized by a plurality of peripheral passages therein to permit the passage of a cement material therethrough; d. applying a cement material to the interior of the reameD cavity and forcing some of the cement through the passageways of the cement restrictor device; e. inserting a prosthetic socket element into the cement-coated cavity; and f. hardening the cement to secure the cement restrictor to the holes and the socket element within the cavity.

Claim 11

In a method of replacing a diseased or damaged hip which comprises: a. reaming a cavity into the pelvic bone of a patient; b. drilling a plurality of holes into the bone to provide a means to anchor a socket element therein by the use of a hardenable cement; c. inserting in the holes a cement restrictor device which comprises a raised cap-like upper element defining a cavity therein, the upper element having a continuous solid upper surface, the lower edge of the element adjoined to a peripheral lid element extending outwardly from the lower edge thereof, the lower crown portion of the cap-like element generally adjacent to the adjoinment to the lid element characterized by a plurality of peripheral passages therein to permit the passage of a cement material therethrough; d. applying a cement material to the interior of the reameD cavity and forcing some of the cement through the passageways of the cement restrictor device; e. inserting a prosthetic socket element into the cement-coated cavity; and f. hardening the cement to secure the cement restrictor to the holes and the socket element within the cavity.

Claim 12

The method of claim 8 wherein the cement restrictor device and the socket element are composed of the same or similar polymeric material.

Claim 13

The method of claim 8 wherein the cement restrictor device is composed of high-density polyethylene.

Claim 14

The method of claim 8 wherein the cement material is a dough-like composition of polymethylmethacrylate.

Claim 15

The method of claim 8 wherein the passageways in the cement restrictor device are slot passageways equally distributed about the periphery, the device is composed of a polymeric material, and the upper element comprises a hemispherical dome-like element.