Surgery – Instruments – Orthopedic instrumentation
Reexamination Certificate
1999-07-02
2001-04-17
Mancene, Gene (Department: 3732)
Surgery
Instruments
Orthopedic instrumentation
C606S092000, C606S094000
Reexamination Certificate
active
06217581
ABSTRACT:
FIELD OF THE INVENTION
The invention relates to devices for applying cement under pressure to bone cavities or interstices, for example for treating osteoporosis and to methods for repairing bone prosthesis in situ, particularly artificial hip joints.
BACKGROUND OF THE INVENTION
A conventional technique for treating hip diseased hip joints involves the replacement of the patients diseased hip joint by the substitution of a prosthetic hip joint having a pin which is anchored by cement in the femur cavity to secure the hip joint to the femur. When fitting the joint, the top of the femur in the region of the trabeculae is cut open and the bone marrow removed through the top opening by a scooping and suction technique, emptying the bone cavity or medullary canal for the receipt of the pin and a two-part epoxy cement injected into the cavity through the top opening to spread around the pin using a gun, similar in construction to a caulking gun. Caps of various selected sizes are required to be fitted around the gun nozzle to seal the top opening during injection in an attempt to permit a relatively modest pressure increase to perhaps 2-3 p.s.i. in an attempt to completely fill all interstices around the pin.
However, the pin is made of titanium which is much harder than the cement and as a result of the difference in hardness, after the joint has been in use for a number of years, typically about 10 years, hairline cracks or interstices develop at the interface of the titanium pin and epoxy cement. The conventional remedy has required that the entire joint (pin) be removed and replaced which is effectively a repeat of the earlier procedure which is an undesirable major operation.
It is also known to completely fill a medullary canal with cement through an opening cut in the bone in the upper end for the treatment of osteoporosis.
Examples of devices and mechanisms previously used to instal the artificial joint are described in the catalogue of Stryker Instruments, MI, PT No 1000-119 rev C; PT. NO. 1000-310 REV B1; BP NO 1000-340 for their bone preparation systems, third generation cementing technique and cement injection system.
SUMMARY OF THE INVENTION
It is one object of the invention to provide an apparatus and method which will obviate the requirement to remove and replace the artificial joint as a result of the development of hairline cracks or interstices at the interface of the prosthesis pin and cement.
It is another object of the invention to provide an apparatus and method permitting the injection of the cement at very high pressures into the bone cavity or medullary canal and interstices to ensure maximum intrusion of cement therein.
According to one aspect, the invention provides an adaptor for injecting cement dispensed under high pressure from a cement gun into a bone cavity or into an interstice in a joint formed between a prosthetic pin and cement in the cavity anchoring the pin in the cavity thereby to repair the joint, comprising an elongate body with leading, penetrating and rear, connecting ends, the body having a pointed penetrating shank which tapers outward as it extends rearward from the leading end and is formed with an external self-tapping screw thread and a fingerpiece protruding radially outward adjacent the rear end comprising a pair of wings which protrude forward while diverging in opposite radial directions and an internal cement passageway extending axially completely through the body communicating with leading and rear ends, the rear end being provided with means for attachment to a zerk attached to a cement outlet of the gun so that, with the zerk attached to the rear end, the leading end can be manually screwed into sealing engagement with a bore tapped into the bone and an outlet hose of the cement gun secured to the zerk so that cement dispensed under high pressure from the gun will be injected through the adaptor into the cavity or interstice to fill and seal the interstice securing the pin in the bone cavity.
According to another aspect, the invention provides a kit for injecting cement into a bone cavity or into an interstice in a joint formed between a prosthetic pin and cement in a femur cavity achoring the pin in the cavity thereby to fill the cavity and repairing the joint comprising a hydraulic, trigger action high pressure gun, two flexible hoses, a zerk, two adapters, two plugs and a pressure release valve, each adaptor comprising an elongate body with leading, penetrating and rear, connecting ends, the body having a pointed penetrating shank which tapers outward as it extends rearward from the leading end and is formed with an external screw thread and a fingerpiece protruding radially outward adjacent the rear end and an internal glue passageway extending axially completely through the body communicating with leading and rear ends, the rear end being formed with an internal screw thread for attachment to a zerk so that the adapters with one having a zerk attached to a rear end can be manually screwed into sealing engagement with respective bores tapped into a femur into communication with an interstice therein and the outlet hose of the gun secured to the zerk and the pressure release valve secured between the other adapter and the other hose so that cement dispensed under high pressure from the gun injected through the one adapter into the femur cavity will fill the interstice and seal the joint, with the adapters subsequently unscrewed from the respective bores and the plugs fitted in respective bores to seal the cavity.
The invention includes a method for repairing a hairline crack or interstice in a joint between a prosthetic anchoring pin and a anchoring cement in bone receiving the pin, without removing the pin from the bone and a method for treating osteoporosis in which the marrow is displaced from the medullary canal by injection of cement under high pressure to reinforce the bone.
The screw threaded adaptor and zerk seal against back pressure enabling a lever operated, hydraulic action, gun known for greasing automobiles and which is widely available at low cost to be used for regluing operations to apply glue rapidly under very high pressure (e.g 7,500 psi-10,500 p.s.i.). Furthermore, as the adapters have fingerpieces they may, with zerks attached, readily be screwed by hand into pilot bores tapped in the boney mass
Aspects of various devices described herein are described in my application Ser. No. 08/969,949 filed Nov. 25, 1997 which is a continuation in part application of Ser. No. 08/544,557 filed Oct. 18, 1995, the disclosure of which is incorporated herein by reference.
REFERENCES:
patent: 131408 (1872-09-01), Peacock
patent: 2040126 (1936-05-01), Grieve
patent: 2570588 (1951-10-01), Nylund
patent: 3352336 (1967-11-01), Smith
patent: 3892621 (1975-07-01), Salonen
patent: 4132516 (1979-01-01), Story
patent: 4338925 (1982-07-01), Miller
patent: 4420358 (1983-12-01), Kindt
patent: 4555286 (1985-11-01), Orisaka et al.
patent: 4576152 (1986-03-01), Muller
patent: 4593685 (1986-06-01), McKay et al.
patent: 4625722 (1986-12-01), Murray
patent: 4627434 (1986-12-01), Murray
patent: 4780162 (1988-10-01), Forler et al.
patent: 4815454 (1989-03-01), Dozier, Jr.
patent: 4826373 (1989-05-01), Nakaro
patent: 4865229 (1989-09-01), Schneider
patent: 4869403 (1989-09-01), Bruning
patent: 4976372 (1990-12-01), Rogers, Jr.
patent: 5115844 (1992-05-01), Hanson
patent: 5178712 (1993-01-01), Sakai et al.
patent: 5214987 (1993-06-01), Fenton
patent: 5249716 (1993-10-01), Sullivan
patent: 5249899 (1993-10-01), Wilson
patent: 5370273 (1994-12-01), Rohloff et al.
patent: 5928468 (1999-07-01), Tolson
patent: 6045555 (2000-04-01), Miller
K-P Manufacturing Co, (Minneapolis) Catalogue Pages Showing Grease Guns n.3-5486-35582 (Page 2); Inflating Needles Part Nos 3197; Grease Fitting 3-5331-35368; Grease Gun Hose & Accessories Part Nos 3-2015-32127.
K-P Manufacturing Co, Minneapolis, Catalogue Published 1984 Pages Showing Grease Guns No. 3-5486-35582 (Page 2); Grease Fitting 3-5331-35368; Grease Gun Hose & Accessories Parts 3-2015-32127.
Nation
Mancene Gene
Priddy Michael B.
Usher Robert W. J.
LandOfFree
High pressure cement injection device for bone repair does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with High pressure cement injection device for bone repair, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High pressure cement injection device for bone repair will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2469227