A surgical implant having a surface treatment which contains primary cavities and secondary cavities. The primary cavities are larger than the secondary cavities and the primary cavities have an average length ranging from 20-500 micrometers. The surface treatment includes recasted material adjacent to a plurality of the primary cavities.

Compositions and methods for etching an implantable device having a cobalt chrome surface are disclosed. The compositions generally include at least two mineral acids, iron (Fe), and certain component metals of the cobalt chrome to be etched. For example, when etching a cobalt chromium molybdenum alloy, the metals may include chromium (Cr), molybdenum (Mo), and optionally, cobalt (Co). The at least two mineral acids may include hydrochloric acid (HCl), nitric acid (HNO.sub.3), and hydrofluoric acid (HF). Alternatively, the composition may be an electrolyte composition useful for electrochemical etching of the implantable device. These compositions and methods may generate nanoscale geometry on the surface of the implantable device to provide implants with improved osseointegration, biocompatibility, and healing after surgery.

An oblique expanding fusion cage device including a body with a superior portion and an inferior portion. The superior portion and the inferior portion have a proximal end and a distal end. The fusion cage device also includes a pathway, an opening, and an expanding member. The pathway travels from the proximal end to the distal end of the device between the superior and inferior portions. The opening in the proximal end of the body enables access to the pathway. The expanding member may be re movably inserted into the opening and is moveable toward the distal end of the body, wherein the expanding member engages the superior portion and the inferior portion as the expanding member moves distally within the pathway.

A surgical implant having a surface treatment which contains primary cavities and secondary cavities. The primary cavities are larger than the secondary cavities and the primary cavities have an average length ranging from 20-500 micrometers. The surface treatment includes recasted material adjacent to a plurality of the primary cavities.

A modular acetabular cup assembly for use with multiple bearing liners is disclosed. The acetabular cup assembly includes a shell having a tapered inner wall and two circumferential grooves. The shell may be used with polyethylene, ceramic, metal, and other types of liners.

A titanium 6 Al/4V alloy is provided with a surface topography that is similar to the Osseotite surface produced on commercially pure titanium. Native oxide is removed from the Ti 6Al/4V alloy, followed by contacting the metal at ambient temperature with an aqueous hydrochloric acid solution containing a relatively small amount of hydrofluoric acid.

A modular acetabular cup assembly for use with multiple bearing liners is disclosed. The acetabular cup assembly includes a shell having a tapered inner wall and two circumferential grooves. The shell may be used with polyethylene, ceramic, metal, and other types of liners.

An oblique expanding fusion cage device including a body with a superior portion and an inferior portion. The superior portion and the inferior portion have a proximal end and a distal end. The fusion cage device also includes a pathway, an opening, and an expanding member. The pathway travels from the proximal end to the distal end of the device between the superior and inferior portions. The opening in the proximal end of the body enables access to the pathway. The expanding member may be removably inserted into the opening and is moveable toward the distal end of the body, wherein the expanding member engages the superior portion and the inferior portion as the expanding member moves distally within the pathway.

Medical devices in accordance with various embodiments of the present invention employ one or more coaxial screw gear sleeve mechanisms. In various embodiments, coaxial screw gear sleeve mechanisms include a post with a threaded exterior surface and a corresponding sleeve configured to surround the post, the corresponding sleeve having a threaded interior surface configured to interface with the threaded exterior surface of the post and a geared exterior surface. A drive mechanism can be configured to interface with the geared exterior surface of the sleeve, causing the device to expand.

A ball and socket assembly including a ball component with a notch formed therein. The socket is a one-piece structure including an opening sized to receive the ball component. The ball is a capable of being inserted into the socket when the notch, cavity, or undercut is properly oriented relative to the opening of the one-piece socket.