Abstract: A system is described for long-term controlled release delivery of a drug or a therapeutic agent. According to the invention, one or more drugs or therapeutic agents contained in microspheres are mixed with a temperature sensitive hydrogel which is then introduced directly to the desired situs of the drug or therapeutic agent. The temperature sensitive hydrogel may also contain a drug or a therapeutic agent, for example, a pain relieving drug, for a short-term controlled release. The temperature sensitive hydrogel is in liquid state at room temperature, but upon injection, shortly becomes gelatinous. This system is particularly suitable for treatment of diseases, disorders, or conditions, for example, tumors, discogenic back pain, or arthritis, warranting localized administration of a drug or a therapeutic agent. In addition, the specification provides a method for production of a drug- or therapeutic agent-containing microspheres.

Abstract: The methods and compositions disclosed herein describes a solution containing at least one block co-polymer that is a liquid at lower temperatures and transitions to a gel at higher temperatures. The compositions are useful, for example, as an alternative to saline or silicone-gel as fillers for prostheses.

Abstract: The present invention is directed to a polymeric prosthesis precoated with a bone cement compatible polymer. The bone cement compatible polymer coating, is provided by an activated powder mixture of polymethyl methacrylate and ultra high molecular weight polyethylene which is bonded to the outer surface of the prosthesis by sintering. Once bonded to a polymeric prosthesis in accordance with the present invention, the precoat strengthens the interface between a bone cement and a prosthesis when the prosthesis is later implanted. The inner layer of the prosthesis may be provided of cross-linked UHMWPE powder sintered with virgin UHMWPE powder or fibers to provide a intermediate layer(s) of the coating present on the prosthesis. The precoat also decreases the likelihood that the prosthesis will loosen and break away from the cement over time.

Abstract: The present invention is directed to a polymeric prosthesis precoated with a bone cement compatible polymer. The bone cement compatible polymer coating, is provided by an activated powder mixture of polymethyl methacrylate and ultra high molecular weight polyethylene which is bonded to the outer surface of the prosthesis by sintering. Once bonded to a polymeric prosthesis in accordance with the present invention, the precoat strengthens the interface between a bone cement and a prosthesis when the prosthesis is later implanted. The inner layer of the prosthesis may be provided of cross-linked UHMWPE powder sintered with virgin UHMWPE powder or fibers to provide a intermediate layer(s) of the coating present on the prosthesis. The precoat also decreases the likelihood that the prosthesis will loosen and break away from the cement over time.

Abstract: An improved method for reinforcing a prosthetic implant and an implant product are provided. The method includes embedding a support structure in a bed of bone cement surrounding the distal end of a prosthetic device. The support structure counteracts hoop-stress imparted to the implant, decreases creep of the bone cement, and further reinforces the bone cement bed. In various embodiments, the support structure can be in the form of a metal coil, in the shape of a wire mesh, or in the design of a coil reinforced centralizer. Prior to being implanted, the support structure can be precoated with bone cement or can be prefabricated with a prosthetic device.

Abstract: The present invention is directed to a polymeric prosthesis precoated with a bone cement compatible polymer. The bone cement compatible polymer coating, is provided by an activated powder mixture of polymethyl methacrylate and ultra high molecular weight polyethylene which is bonded to the outer surface of the prosthesis by sintering. Once bonded to a polymeric prosthesis in accordance with the present invention, the precoat strengthens the interface between a bone cement and a prosthesis when the prosthesis is later implanted. The inner layer of the prosthesis may be provided of cross-linked UHMWPE powder sintered with virgin UHMWPE powder or fibers to provide a intermediate layer(s) of the coating present on the prosthesis. The precoat also decreases the likelihood that the prosthesis will loosen and break away from the cement over time.

Abstract: The present invention discloses a nut to be used in a spinal screw and plate assembly to affix the screw and plate assembly to the spinal bone. The nut has a polymer insert that when contacted with a screw allows a bone plate and screw structure to relax over time.

Abstract: An improved method for reinforcing a prosthetic implant and an implant product are provided. The method includes embedding a support structure in a bed of bone cement surrounding the distal end of a prosthetic device. The support structure counteracts hoop-stress imparted to the implant, decreases creep of the bone cement, and further reinforces the bone cement bed. In various embodiments, the support structure can be in the form of a metal coil or in the shape of a wire mesh. Prior to being implanted, the support structure can be precoated with bone cement or can be prefabricated with a prosthetic device.

Abstract: The present invention is directed to a polymeric prosthesis precoated with a bone cement compatible polymer. The bone cement compatible polymer coating, which can be polymethyl methacrylate, is bonded to the outer surface of the prosthesis. For instance, in one embodiment, the bone cement compatible polymer coating is believed to be copolymerized with the polymeric prosthesis. Once bonded to a polymeric prosthesis in accordance with the present invention, the precoat strengthens the interface between a bone cement and a prosthesis when the prosthesis is later implanted. The precoat also decreases the likelihood that the prosthesis will loosen and break away from the cement over time. The polymeric implant product of the present invention is particularly well suited for use as an acetabular cup or a tibia plateau in replacing hip joints and knee joints respectively.

Abstract: A process of orthopedic implantation of prosthetic devices such as hip and knee joints. The prepared bed of the bone cavity is lined with a pre-coating mixture of bone cement and resorbable particles, followed by filling of the bed with substantially pure bone cement and thereafter the prosthesis is positioned into the fully prepared bed. In this manner, resorbable particles along the lined prepared bed wall are resorbed by the patients body and replaced with new bone tissue ingrowth. As a result bonding of the bone cement to the bone is substantially improved, without weakening the bonding of the implant to the bone cement.

Abstract: A non-stress-shielding bone fracture healing compression device is to be used with screws, pins or nails for attaching the device to bone tissue. A rigid plate has at least two openings therethrough for purposes of attaching the plate to the bone with screws, pins or nails. At least one of the openings is a relaxation opening that has an opening surface shaped at least in part as a truncated spherical section and has an entrance hole through the top of the plate and an exit hole through the bottom of the plate. The polymer member is shaped to conform to the opening surface and to form circular entrance and exit holes concentric with the respective relaxation opening surface entrance and exit holes. The polymer member can be either resorbable material or viscoelastic material and can be configured to cover either all or less than all of the opening surface of the relaxation opening.

Abstract: An apparatus for connecting a structure with a vertebral body of a spinal column and for transmitting a load between the structure and the vertebral body. The apparatus includes a fastener with a threaded portion for threaded engagement with a surface defining an opening in the vertebral body to connect the vertebral body with the structure. A spacer is adapted to be located between the fastener and the structure for transmitting load therebetween. The spacer is made of a material which plastically deforms as a function of time and load applied thereto to decrease the load transmitted between the vertebral body and the structure.

Abstract: A pair of screens in the barrel of a bone cement syringe improves the strength of the bone cement by breaking large bubbles into many small bubbles.

Abstract: An improved process for orthopedic implantation of a prosthesis where the prosthesis has a polymer coating on substantially the entire surface of same that is to be affixed to the bone by bone cement, the polymer coating being substantially completely polymerized and exhibiting a virtually pore free outer surface. After preparation of the bone cavity, a bone cement, preferably a self-curing acrylic is inserted into the bone cavity, after which the precoated prosthesis is properly positioned therein. The polymeric coating on the prosthesis should be compatible with the bone cement to achieve a chemical bond therebetween. A precoated prosthesis is also disclosed and claimed.