Patent Publication Number: US-2011054611-A1

Title: Implant Structure

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to medical implant structures. More particularly, the present invention relates to an implant structure for medical repair and fixation of damaged bones. 
     2. Description of Related Art 
     Owing to advancements in medical technology, an ageing society is here with us today. With an ever-increasing ageing population, geriatric care and medical treatment for chronic diseases are becoming more important. 
     In such an ageing society, degenerative arthritis, which is common among people over 50, is drawing attention. The elderly with severe degenerative arthritis usually have aching knees and thus are crippled to the detriment of their daily routine. 
     Degenerative arthritis develops because of wear and tear of the cartilage of a joint and ends up with the deformed joint and cracks on the surface of the bone involved. Hence, degenerative arthritis is treated with medication or surgery, depending on the damage done to the bone. Where a joint affected by degenerative arthritis is worn out to the extent that medication or rehabilitative therapy is inadequate to alleviate symptoms of degenerative arthritis, a surgeon replaces the damaged joint with an implant to restore joint functions. 
       FIG. 1  is a perspective view of a conventional implant structure  10 .  FIG. 2  is an exploded perspective view of the conventional implant structure  10 . Referring to  FIG. 1  and  FIG. 2 , the conventional implant structure  10  comprises a fixing mechanism  11 , a coupling mechanism  12 , and an implant mechanism  13 . The fixing mechanism  11  is configured to be implanted in a damaged bone. After the fixing mechanism  11  has been fixed in position to the bone, the implant mechanism  13  can be coupled to the fixing mechanism  11  by means of the coupling mechanism  12 , such that the implant structure  10  is fixed in position to the damaged bone. 
     Human joints are evolved to be heavy-duty in terms of frequency of use and directions of applied forces. Hence, given time, the fixing mechanism  11  of the implant structure  10  implanted in the bone of a patient is likely to be loosened and displaced under the forces exerted upon the implant structure  10  (which acts as a substitute for the otherwise damaged joint of a patient), and the coupling mechanism  12  may deform so that the implant mechanism  13  becomes disconnected from the fixing mechanism  11 . Thus, the service life of the implant structure  10  is shortened significantly. 
     Furthermore, in situations where the implant mechanism  13  of the implant structure  10  is relatively large, a plurality of said fixing mechanisms  11  are essential to enhancement of the bonding of the implant structure  10  and the damaged bone. In such situations, accurate alignment of the implant mechanism  13  and the fixing mechanism  11  is of vital importance, and as a consequence, it is rather difficult to implant the implant structure  10  in the damaged bone. 
     SUMMARY OF THE INVENTION 
     The present invention provides an implant structure having a nailing portion formed with a barb unit for enhancing the bonding between the implant structure and a bone to thereby prevent the implant structure from displacement. 
     The present invention provides an implant structure having an implant body and a nailing portion, wherein the implant body and the nailing portion are integrally formed as a unitary structure to thereby prevent separation of the implant body and the nailing portion. 
     The present invention provides an implant structure having an implant body and a nailing portion, wherein the implant body and the nailing portion are integrally formed as a unitary structure to thereby streamline implantation of the implant structure in a bone; hence, implantation of the implant structure is simplified. 
     To achieve the above and other objectives, the present invention provides an implant structure, comprising: an implant body having a first surface, a second surface, and a third surface, with the first and second surfaces adjoining via a rim shared therebetween and the second and third surfaces adjoining via a rim shared therebetween; and at least one nailing portion having a bone-contacting surface with at least one barb unit formed thereon, wherein the implant body and the said nailing portion are integrally formed as a unitary structure. 
     Implementation of the present invention involves at the least the inventive steps as follows: 
     1. With the implant body and the nailing portion being integrally formed as a unitary structure, separation of the implant body and the nailing portion is prevented. 
     2. The nailing portion is formed with the barb unit for enhancing the bonding of the implant structure and a bone to thereby prevent the implant structure from loosening or displacement. 
     3. With the implant body and the nailing portion being integrally formed as a unitary structure in advance, implantation is simplified. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The features and advantages of present invention are described in detail hereunder to enable persons skilled in the art to understand and implement the disclosure of the present invention and readily apprehend objectives and advantages of the present invention with references made to the disclosure contained in the specification, the claims, and accompanying drawings, wherein: 
         FIG. 1  is a perspective view of a conventional implant structure; 
         FIG. 2  is an exploded perspective view of the conventional implant structure; 
         FIG. 3  is a perspective view of a first embodiment of an implant structure according to the present invention; 
         FIG. 4  is a perspective view of a second embodiment of the implant structure according to the present invention; and 
         FIG. 5  is a perspective view of a third embodiment of the implant structure according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to  FIG. 3 , there is shown a perspective view of a first embodiment of an implant structure  20  according to the present invention. As shown in the drawing, the implant structure  20  includes an implant body  21  and at least one nailing portion  22 . 
     Referring to  FIG. 3 , the implant body  21  has a first surface  211 , a second surface  212 , and a third surface  213 . After the implant body  21  has been implanted in a bone, the first surface  211  defines the bone-bone contact surface of a joint implanted with the implant structure  20 . Hence, the profile of the first surface  211  is designed as needed, so as to maintain the flatness of the surface of the bone repaired. The second surface  212  and the first surface  211  adjoin via a rim shared therebetween, in order that the implant body  21  to have a certain thickness. The third surface  213  and the second surface  212  adjoin via a rim shared therebetween, so that the implant body  21  has a bottom side. In the first embodiment, the second surface  212  and the third surface  213  are perpendicular to each other, and the implant body  21  is made of alloy or metal. 
     Referring to  FIG. 3 , the third surface  213  of the implant body  21  is further provided with a plurality of fixing units  214  thereon. The fixing units  214  are needle-shaped and thereby assist in fixing the third surface  213  to the surface of the bone and enhancing the bonding between the implant structure  20  and the bone. Likewise, the fixing units  214  are made of alloy or metal. 
     Referring to  FIG. 3 , the nailing portion  22  and the implant body  21  are integrally formed as a unitary structure. The nailing portion  22  is formed on and extends from the third surface  213 . The nailing portion  22  has a bone-contacting surface with at least one barb unit  215  formed thereon. Referring to  FIG. 4  and  FIG. 5 , there are shown perspective views of second and third embodiments of the implant structure according to the present invention, respectively. As shown in the drawings, implant structures  30  and  40  comprise two said nailing portions  22  and three said nailing portions  22 , respectively. Each of the nailing portions  22  of the implant structures  30  and  40  has a bone-contacting surface with the at least one barb unit  215  formed thereon. When two or more said barb units  215  are provided, the barb units  215  are preferably positioned on two opposing sides of the nailing portion  22  for improved fixing. 
     To be implanted in a bone, the implant structure  20  that comes in a single piece is not screwed into the bone as taught by the prior art but is directly nailed into the bone. Hence, the at least one barb unit  215  on the bone-contacting surface of the nailing portion  22  engage with the bone so as to counterbalance an upward pull exerted upon the implant structure  20 . Also, with the implant structure  20  being a unitary structure, separation between the implant body  21  and the nailing portion  22  is efficiently prevented. 
     Referring to  FIG. 4  and  FIG. 5 , with the two said nailing portions  22  and three said nailing portions  22 , respectively situated on the implant structures  30  and  40 , the latter serves as artificial joints. Thus, the implant structures  30  and  40  can better oppose a rotational force exerted thereon and thus are unlikely to loosen. Since the implant body  21  and the nailing portions  22  of each of the implant structures  30  and  40  are integrally formed as a unitary structure, artificial joint implantation surgery is easier than ever before, and the resultant bonding between the implant structures  30  and  40  with the bone is stronger than ever before. 
     Referring to  FIG. 3  through  FIG. 5 , each of the nailing portions  22  of the implant structures  20 ,  30 , and  40  is further provided with at least one recess  216  or at least one cavity  217 . The said recess  216  or the said cavity  217  serves to receive a metal frame (not shown). The metal frame is coated with hydroxylapatite for providing a favorable growth environment for the bone with a view to promoting osteogenesis and enhancing the bonding between the implant structures  20 ,  30 ,  40  and the bone. 
     The foregoing descriptions of the embodiments are provided to illustrate the features of the present invention and enable those in the art to gain insight into the present invention and implement the present invention, but are not intended to restrict the scope of the present invention. It should be understood by those in the art that equivalent modifications and variations in the aforesaid embodiments of the present invention can be made without departing from the spirit and principle in the disclosure of the present invention and still fall within the scope of the invention as set forth in the appended claims.