초록 ▼

Method and apparatus for promoting a spinal fusion between neighboring vertebrae. Apparatus may be located within the intervertebral disc space and preferably includes a pair of engaging plates for contacting the vertebrae. An alignment device may be used to alter the vertical distance between the e

Method and apparatus for promoting a spinal fusion between neighboring vertebrae. Apparatus may be located within the intervertebral disc space and preferably includes a pair of engaging plates for contacting the vertebrae. An alignment device may be used to alter the vertical distance between the engaging plates to customize the apparatus to fit a given patient. In one embodiment, the alignment device includes a pair of struts having a predetermined height and extending between the engaging plates from an anterior end to a posterior end of the apparatus. In another embodiment, the alignment device includes a rotatable connector and cam pins for adjusting the distance between the engaging plates. The alignment device is preferably adapted to vary the distance between the engaging plates such that the height of the apparatus proximate the anterior end is greater than that proximate the posterior end whereby the natural lordosis of the spine is maintained after the apparatus is installed. The apparatus may further include a load-sharing member to allow stress to be imparted to bone in the vicinity of the apparatus to promote bone growth in accordance with Wolff's law.

대표청구항 ▼

Method and apparatus for promoting a spinal fusion between neighboring vertebrae. Apparatus may be located within the intervertebral disc space and preferably includes a pair of engaging plates for contacting the vertebrae. An alignment device may be used to alter the vertical distance between the e

Method and apparatus for promoting a spinal fusion between neighboring vertebrae. Apparatus may be located within the intervertebral disc space and preferably includes a pair of engaging plates for contacting the vertebrae. An alignment device may be used to alter the vertical distance between the engaging plates to customize the apparatus to fit a given patient. In one embodiment, the alignment device includes a pair of struts having a predetermined height and extending between the engaging plates from an anterior end to a posterior end of the apparatus. In another embodiment, the alignment device includes a rotatable connector and cam pins for adjusting the distance between the engaging plates. The alignment device is preferably adapted to vary the distance between the engaging plates such that the height of the apparatus proximate the anterior end is greater than that proximate the posterior end whereby the natural lordosis of the spine is maintained after the apparatus is installed. The apparatus may further include a load-sharing member to allow stress to be imparted to bone in the vicinity of the apparatus to promote bone growth in accordance with Wolff's law. An ophthalmic lens as defined in claim 1 wherein each of the first and second lenses has an optical axis, the power of each of the first and second lenses changes along a power curve in a radially outward direction from the associated optical axis and the power curve for the first lens is different from the power curve of the second lens. 11. An ophthalmic lens system as defined in claim 10 which provides a reduced level of suppression relative to a similar lens combination with lenses having substantially similar power curves. 12. An ophthalmic lens system as defined in claim 1 wherein the first lens provides better visual acuity for objects at infinity than the second lens. 13. An ophthalmic lens system as defined in claim 1 wherein the second lens has a zone with an intermediate add power for intermediate vision correction and the zone has optical aberrations which increase the depth of focus of the zone. 14. An ophthalmic lens system as defined in claim 13 wherein the zone extends radially outwardly and has progressively increasing powers as the zone extends radially outwardly. 15. An ophthalmic lens system as defined in claim 1 wherein the first and second lenses are intraocular lenses. 16. An ophthalmic lens system as defined in claim 1 wherein the first and second lenses are selected from the group consisting of contact lenses and corneal inlays. 17. An ophthalmic lens system for improving the vision of a patient comprising: a first multifocal ophthalmic lens for use with one eye of a patient, the first lens having a power including a first baseline diopter power for distance vision correction for the patient; a second multifocal ophthalmic lens for use with the other eye of the patient, the second lens having a second baseline diopter power other than for distance vision correction, a power including an intermediate add power for intermediate vision correction for the patient and a maximum power which is less than the full add power required for near vision correction for the patient; the first lens providing better visual acuity for objects at infinity than the second lens; and each of the first and second lenses being adapted for implantation in an eye or to be disposed on or in a cornea of an eye. 18. An ophthalmic lens system as defined in claim 17 wherein the second baseline diopter power is more myopic than the first baseline diopter power. 19. An ophthalmic lens system as defined in claim 17 wherein the second baseline diopter power is for intermediate vision correction. 20. An ophthalmic lens system as defined in claim 17 wherein the maximum add power of any region of the second lens is no greater than about the intermediate add power. 21. An ophthalmic lens system as defined in claim 17 wherein the maximum add power of any region of the first lens is less than the full add power required for near vision correction for the patient. 22. An ophthalmic lens system as defined in claim 17 wherein the maximum add power of any region of the first lens is no greater than about the intermediate add power. 23. An ophthalmic lens system as defined in claim 17 wherein the second lens is biased for near vision correction for the patient. 24. An ophthalmic lens system as defined in claim 17 wherein each of the first and second lenses has an optical axis, the power of each of the first and second lenses changes along a power curve in a radially outward direction from the associated optical axis and the power curve for the first lens is substantially similar to the power curve for the second lens. 25. An ophthalmic lens as defined in claim 17 wherein each of the first and second lenses has an optical axis, the power of each of the first and second lenses changes along a power curve in a radially outward direction from the associated optical axis and the power curve for the first lens is different from the power curve of the second lens. 26. An ophthalmic lens system as defined in claim 25 which provides a reduced level of suppression relative to a similar lens combination in which the power curves of the first and second lens are substantially similar. 27. The ophthalmic lens systems as defined in claim 17 wherein the first and second lenses are intraocular lenses. 28. An ophthalmic lens system as defined in claim 17 wherein the first and second lenses are selected from the group consisting of contact lenses and corneal inlays. 29. An ophthalmic lens system for improving the vision of a patient comprising: a first multifocal lens for use with one eye of the patient, the first lens having a first optical axis and a first baseline diopter power for distance vision correction, the power of the first lens changes along a first power curve in a radially outward direction from the first optical axis; a second multifocal lens for use with the other eye of the patient, the second lens having a second optical axis and a second baseline diopter power for other than distance vision correction, the power of the second lens changes along a second power curve in a radially outward direction from the second optical axis; the first and second power curves being substantially similar; and each of the first and second lenses being adapted for implantation in an eye or to be disposed on or in a cornea of an eye. 30. An ophthalmic lens system of claim 29 wherein the maximum add power of any region of the second lens is less than the full add power required for near vision; and the first lens providing better visual acuity for objects at infinity than the second lens and the second lens providing better visual acuity from intermediate to near distance than the first lens. 31. An ophthalmic lens system as defined in claim 29 wherein the second baseline diopter power is more myopic than the first baseline power. 32. An ophthalmic lens system as defined in claim 29 wherein the second baseline diopter power is for intermediate vision correction. 33. An ophthalmic lens system as defined in claim 29 wherein the best visual acuity provided by the second lens is for objects at intermediate distances. 34. An ophthalmic lens system as defined in claim 29 wherein the first and second lenses are intraocular lenses. 35. An ophthalmic lens system as defined in claim 29 wherein the first and second lenses are selected from the group consisting of contact lenses and corneal inlays. 36. An ophthalmic lens system for improving the vision of a patient comprising: a first multifocal ophthalmic lens for use with one eye of a patient, the first lens having a first baseline diopter power and being biased for distance vision; a second multifocal ophthalmic lens for use with the other eye of the patient, the second lens having a second baseline diopter power different from the first baseline diopter power and a maximum power less than the add power required for full near vision correction for the patient, and being biased for intermediate vision; and each of the first and second lenses being adapted for implantation in an eye or to be disposed on or in the cornea. 37. An ophthalmic lens system as defined in claim 36 wherein each of said lenses is an intraocular lens. 38. An ophthalmic lens system as defined in claim 36 wherein the first and second lenses are selected from the group consisting of contact lenses and corneal inlays.