Telescopic vertebral prosthesis

Details Telescopic vertebral prosthesis Telescopic vertebral prosthesis

1999-10-15

2001-01-23

Philogene, Pedro (Department: 3732)

Prosthesis (i.e., artificial body members), parts thereof, or ai

Implantable prosthesis

Bone

C623S017130, C623S017150, C606S071000, C606S075000

Reexamination Certificate

active

06176881

ABSTRACT:

FIELD OF THE INVENTION
The present invention concerns a device for replacing vertebrae from the human spinal column.
BACKGROUND OF THE INVENTION
If a vertebra becomes diseased or suffers a defect, it must be removed from the spinal column. Some spacer implants for replacement of missing vertebrae are known from the related art. The implant includes mutually displaceable parts which permit an adjustment of the length of the implant by means of catch mechanisms, among other things, and two special end plates which serve to anchor the implant in the adjacent intact vertebrae. Such vertebral prostheses or implants are known, for example, from Austrian Patent R 24426 RASHEED or German Patent No. 196 04 246 A1 JEANSON.
The disadvantage of the these and similar vertebral prostheses is that the two mutually displaceable parts are not closed hollow cylinders and therefore the entire vertebral prosthesis has a low rigidity.
The object of this invention is to obtain the biomechanical and physiological properties of the spinal column despite the removal of a vertebra by using a stable vertebral prosthesis that is adjustable in length. Additionally, ease of handling of the vertebral implant in the course of the surgery is also very important.
This invention achieves this object with a device having the features of claim
1
.
SUMMARY OF THE INVENTION
The present invention relates to a vertebral bone prosthetic device having a rigid interior hollow body provided with an outer surface and a catch mechanism thereon. An exterior hollow body has a hole bored therein along a central axis, and is configured and dimensioned to be slidably received by the interior hollow body along the central axis. At least one elastic element projects into the hole thereby reducing the diameter of the bore, and the at least one elastic element engages the catch mechanism for securing the interior hollow body to the exterior hollow body.
In a preferred embodiment of the invention, the vertebral bone prosthetic device has a groove that defines a contact surface, with the groove and the spring having mating conical tapers. At least one hollow body is angled with respect to the central axis, and at least one hollow body has a non-circular cross section.
In another preferred embodiment of the vertebral bone prosthetic device, each catch mechanism includes at least one face defined by a face plane and the at least one face is oriented transverse to a top plane defined by a top end of the interior hollow body. The spring has a pressure-loaded side, with the catch mechanism disposed on the pressure-loaded side.
One embodiment of the device according to this invention includes two telescoping hollow cylinders. The interior hollow cylinder is provided with a catch mechanism on its outer periphery. The exterior hollow cylinder has at least one elastic element which latches into the catch mechanism of the interior hollow cylinder and fixes the length of the device. With the catch mechanism and the latchable elastic element, the device according to this invention can be lengthened and adjusted during surgery.
Another embodiment of the device according to this invention includes two coaxially arranged hollow bodies that are displaceable along said axis relative to one another, a spring mounted in a groove provided in the exterior hollow body and end plates that serve to anchor the device in the adjacent vertebrae. The interior hollow body is provided with a catch mechanism on its outer surface. On its inner surface, the spring has a catch mechanism which fixes the interior hollow body in the axial direction when it latches into the catch mechanism on said interior hollow body. The spring can also be spread from the outside by using an auxiliary instrument through an opening in the exterior hollow body thereby allowing controlled in situ compression. An embodiment with three hollow bodies that can slide into each other is also possible, with the outer and interior hollow cylindrical surfaces each being designed as in the two-part variant described above.
The advantages achieved through this variant of the invention are to be seen essentially as the fact that a spring with a catch mechanism is built into the device according to this invention to fix the length of the implant. The overall height of the implant can thus be reduced, and when the clearance is small, it can be inserted between adjacent vertebrae, which thus permits the use of this prosthesis even in the vicinity of the cervical vertebrae. By spreading the spring, the vertebral prosthesis according to this invention can be compressed again and removed. In addition, the two hollow cylinders may have relatively thick walls and thus may form a very stable prosthesis.


REFERENCES:
patent: 4554914 (1985-11-01), Kapp et al.
patent: 5236460 (1993-08-01), Barber
patent: 5489308 (1996-02-01), Kuslich et al.
patent: 5702453 (1997-12-01), Rabbe et al.
patent: 5723013 (1998-03-01), Jeanson et al.
patent: 5989290 (1999-11-01), Biedermann et al.
patent: 6015436 (2000-01-01), Schonhoffer
patent: 2088066 (1992-01-01), None
patent: 37 41 487 A1 (1989-06-01), None
patent: 40 12 622 C1 (1991-07-01), None
patent: 195 00 170 C1 (1996-02-01), None
patent: 196 04 246 A1 (1996-08-01), None
patent: 0 490 159 A1 (1992-06-01), None
patent: WO 92/01428 (1992-02-01), None
patent: WO 94/18913 (1994-09-01), None

Affiliated with

Also associated with

Rating

Telescopic vertebral prosthesis does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Telescopic vertebral prosthesis, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Telescopic vertebral prosthesis will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2448410