FIELD OF THE INVENTION
The present invention relates generally to a surgical method of joining together a bone and a tissue, and more particularly to an anchoring device by which a tissue is firmly held on to a bone.
BACKGROUND OF THE INVENTION
The U.S. Pat. No. 6,007,566 discloses a system for anchoring tissue to bone. The system comprises an anchorlike implant which is provided with two flukes opposite to each other. The implant is fixed with a bone by means of the two flukes. The anchorlike implant of the prior art system often fails to bring about a good anchoring effect. In another words, the anchorlike implant is vulnerable to being pulled out of the bone in which it is implanted, due to the fact that the pointed flukes are apt to penetrate the bone at the time when the flukes are exerted on by a stress. The stress is bound to concentrate at the pointed end of the flukes of the anchorlike implant as the suturing threads are pulled by the tissue.
SUMMARY OF THE INVENTION
It is the primary objective of the present invention to provide a device for anchoring a tissue to a bone. The device comprises an implant, one or more sutures, and a pasty medicine.
The implant of the device is contractibe prior to being implanted in a bone. Upon completion of being implanted in the bone, the implant is filled with the pasty medicine and is therefore caused to expand to lodge in the bone. With the sutures, one or more pieces of the tissue are anchored to the bone. The sutures are fastened at one end with the implant such that other end of the sutures is extended out of the bone so as to join with the tissue pieces.
A device for anchoring a tissue to a bone according to one aspect of the present invention comprises:
an implant made of a flexible wall and provided with a holding portion and an injection port in communication with said holding portion, with said holding portion being enclosed by said flexible wall which is provided with a plurality of pores, each having a diameter smaller than 0.1 mm whereby said implant is contractible and is contracted prior to being inserted into the bone;
one or more sutures fastened with said implant; and
a pasty medicine capable of solidification injected into said holding portion via said injection port of said implant in the wake of insertion of said implant into the bone, thereby resulting in expansion of said implant so as to enable said implant to be securely lodged in the bone upon completion of the solidification of said pasty medicine.
Preferably, said flexible wall of said implant is of a one-layered construction.
Preferably, said flexible wall of said implant is of a laminated multi-layered construction.
Preferably, said sutures are fastened at one end with said implant.
Preferably, said injection port of said implant is provided with a suture hole for holding said sutures.
Preferably, said implant is integrally made of said flexible wall such that said implant takes the form of sac, bag, or ball.
Preferably, said pasty medicine is a mixture of a liquid and a bone cement. More preferably, said bone cement is selected from the group consisting of gypsum, calcium sulfate, calcium phosphate, poly(methylmethacrylate) and hydroxy apatite.
It is another objective of the present invention to provide a system by which a tissue is anchored to a bone in a surgical operation.
The system of the present invention comprises said implant, said one or more sutures, an injection tool, and said pasty medicine, wherein said injection tool is fastened detachably with said filling member, so that said pasty medicine is injected into said holding portion via said injection tool.
Preferably, said injection tool comprises a connection tube and a syringe formed of a barrel and a plunger, said connection tube being fastened detachably at one end with said injection port of said filling member, said connection tube further being fastened at other end with said barrel of said syringe; wherein said pasty medicine is injected into said holding portion of said filling member from said barrel by said plunger via said connection tube.
Preferably, said system of the present invention further comprises a sleeve receiving said connection tube and said implant prior to insertion of said implant into the bone, wherein said sutures protrude from said sleeve. More preferably, said sleeve is made of a material having an elasticity and has a longitudinal slit, so that said sleeve can be removed from said connection tube by expanding said longitudinal slit.
The pores of the flexible wall of the implant of the present invention allow the bone cells to grow thereinto to help the implant serving as an anchor.
The flexible wall of the implant of the device or system of the present invention is made of a biocompatible or biosynthetic material, such as threads made of titanium or goat intestine.
The flexible wall of the implant of the device or system of the present invention further contains an image-forming body, which is formed of a metal conductor, or graphite. The image-forming body enables the implant to be located in the bone by a ray imaging system, such as an X-ray machine.
If the average diameter of the pores of the flexible wall of the implant of the device or system of the present invention is close to 0.1 mm, the flexible wall is preferably formed of two or more layers which are laminated. Generally speaking, if the particle size of the pasty medicine, such as poly(methylmethacrylate), is relatively large, and the pasty medicine has a high viscosity, the flexible wall can be formed of two layers. If the particle size of the pasty medicine is relatively small, and the pasty medicine has a low viscosity, the flexible wall is preferably formed of three or more layers. In another words, the number of the wall layer depends on the viscosity or particle size of the pasty medicine. If the flexible wall is of a multi-layered construction, the wall layers are laminated in such a manner that the pores of the wall layers are not necessarily corresponding in location to one another.
The flexible wall of the implant of the device or system of the present invention is provided with a thread hole dimensioned to allow passage of one end of the sutures. When the implant of the device or system of the present invention is formed of biocompatible or biosynthetic threads by knitting, the thread hole can be formed by knitting near the injection port of the implant. Alternatively, the sutures can be integrally knitted to the flexible wall of the implant without forming the thread hole.
This specification contains such words as “front”, “rear”, “left”, and “right”. The word “front” refers to a direction in which the device or system of the present invention is moved by a surgeon toward a subject under the surgical treatment. The word “rear” refers to the opposite direction of the “front”. The word “left” refers to a direction in which the device or system of the present invention is moved by the surgeon toward the left arm of the surgeon. The word “right” refers to a direction toward the right arm of the surgeon.
The features and the advantages of the present invention will be more readily understood upon a thoughtful deliberation of the following detailed description of the preferred embodiments of the present invention with reference to the accompanying drawings.
The surgical process of anchoring a soft tissue, such as muscular tissue, to a bone tissue is described hereinafter with reference to FIGS. 5a-5 e. In the first place, a drilling tool 70 is used to make a hole 61 in a bone tissue 60, as illustrated in FIGS. 5a and 5 b. Thereafter, the contracted implant 11, the suturing threads 21, and the connection tube 41 of the injection device 40 are fitted into the sleeve 50, which is then inserted into the hole 61 of the bone tissue 60. The sleeve 50 is withdrawn from the hole 61. The pasty medicine 30, which is held in the receiving space 424 of the barrel 421 of the syringe 42 of the injection device 40 (not shown in FIGS. 5a and 5 b), is injected into the holding portion 114 of the implant 11, thereby resulting in expansion of the flexible wall 112 of the implant 11, as illustrated in FIG. 5c. As a result, the implant 11 is securely lodged in the bone tissue 60 upon solidification of the pasty medicine 30. By widening the slit 51 of the sleeve 50, the sleeve 50 is separated from the connection tube 41 before the connection tube 41 is disconnected with the injection port 115 of the implant 11, as shown in FIG. 5d. Upon completion of the removal of the connection tube 41 and the sleeve 50, the anchorage of two muscular tissues 80 is carried out by suturing, as shown in FIG. 5e. With two surgical sutures 21 along with two suturing needles 211, the two muscular tissues 80 are anchored to the bone tissue 60.