Abstract:
Disclosed is an implant holder for an implant device comprising a locking mechanism that in a first position causes a clamp coupled to an implant device to lock such that the clamp cannot be decoupled from the implant device, and in a second position causes the clamp to unlock the implant device such that the clamp remains coupled to the implant device in the absence of a sufficient decoupling force but is decoupled from the implant device in the presence of a sufficient decoupling force. Also disclosed are methods of implanting an implant device using an implant holder by coupling the implant device to the implant holder, locking the implant device and the implant holder, emplacing the implant device utilizing the implant holder, unlocking the implant device and the implant holder such that the implant device is still coupled to the implant holder but can be decoupled with sufficient force.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 12/757,443. entitled “Intervertebral Implant” (filed Apr. 9, 2010), the contents of which are incorporated herein by reference in their entirety. 
     
    
     BACKGROUND 
       [0002]    Historically, complete removal of a disc from between adjacent vertebrae resulted in the need to immovably fuse the adjacent vertebrae together, and this “spinal fusion” procedures is still used today as a widely-accepted surgical treatment for disc removal stemming from, for example, a degenerative disc disease or disc injury. However, in many instances, disc arthoplasty—the insertion of an artificial intervertebral disc into the intervertebral space between adjacent vertebrae—may be preferable to spinal fusion as the former may help preserve some limited universal movement of the adjacent vertebrae with respect to each other whereas the latter does not. As such, the objective of total disc replacement is not only to diminish pain caused by a degenerated disc, but also to restore anatomy (disc height) and maintain mobility in the functional spinal unit so that the spine remains in an adapted “sagittal balance” (the alignment equilibrium of the trunk, legs, and pelvis necessary to maintain the damping effect of the spine). 
         [0003]    Several forms of intervertebral implants include an upper part mounted to an adjacent vertebra, a lower part mounted to another adjacent vertebra, and a rotation-assist insert located between these two parts. In addition these intervertebral implants are often very small—perhaps ten millimeters wide and a few millimeters high—and are thus difficult for surgeons to hold, orient, and emplace when using just their fingers. Nevertheless, implantation of these intervertebral devices (or “implant devices”) requires precise and careful emplacement in order to ensure correction functioning. 
       SUMMARY 
       [0004]    To assist with the correct emplacement of an implant device, an insertion tool comprising an implant holder may be utilized. Generally the implant holder must be able to firmly affix to the implant device in order to allow the surgeon to use the necessary pressure and force required to properly emplace the implant device, but then disengage from the implant device once the implant device is correctly positioned and enable the implant holder to be completely withdrawn. 
         [0005]    Disclosed herein are various embodiments directed to an implant holder for an implant device comprising a clamp for coupling to and decoupling from the implant device, and a locking mechanism that, in a first position, causes the clamp to lock the implant device such that the clamp cannot be decoupled from the implant device, and in a second position, causes the clamp to unlock the implant device such that the clamp remains coupled to the implant device in the absence of a sufficient decoupling force (such as a surgeon force, defined later herein) but is decoupled from the implant device in the presence of a sufficient decoupling force. 
         [0006]    Also disclosed herein are several methods of implanting an implant device using an implant holder comprising coupling the implant device to the implant holder, locking the implant device and the implant holder, emplacing the implant device utilizing the implant holder, unlocking the implant device and the implant holder such that the implant device is still coupled to the implant holder, and uncoupling the implant device from the implant holder and withdrawing the implant holder. 
         [0007]    This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    To facilitate an understanding of and for the purpose of illustrating the present disclosure, exemplary features and implementations are disclosed in the accompanying drawings, it being understood, however, that the present disclosure is not limited to the precise arrangements and instrumentalities shown, and wherein similar reference characters denote similar elements throughout the several views, and wherein: 
           [0009]      FIG. 1A  is a perspective view of a pair of vertebral bodies separated by an intervertebral space; 
           [0010]      FIG. 1B  is a side elevation view illustrating the insertion of an intervertebral implant into the intervertebral space between the two vertebral bodies of  FIG. 1A ; 
           [0011]      FIG. 1C  is a perspective view of the vertebral bodies of  FIGS. 1A and 1B  with an intervertebral implant inserted into the intervertebral space; 
           [0012]      FIG. 2A  is a perspective view of the intervertebral implant illustrated in  FIG. 1B  which includes first and second endplates and an articulation disposed between the endplates; 
           [0013]      FIG. 2B  is a side elevation view of the intervertebral implant illustrated in  FIG. 2A ; 
           [0014]      FIG. 3A  is a perspective view of an exemplary implementation of an implant holder clamp utilized by several implant holder embodiments disclosed herein; 
           [0015]      FIG. 3B  is a top elevation view of the exemplary implementation of the clamp of  FIG. 3A ; 
           [0016]      FIG. 3C  is a side elevation view of the exemplary implementation of the clamp of  FIGS. 3A and 3B ; 
           [0017]      FIG. 4A  is a perspective view of the implant holder clamp of  FIGS. 3A ,  3 B, and  3 C being coupled to an intervertebral implant of  FIGS. 2A and 2B  (the latter still housed in sterile packaging); 
           [0018]      FIG. 4B  is a top view of the implant holder coupled to the intervertebral implant (and together removed from the sterile packaging of  FIG. 4A ); 
           [0019]      FIG. 4C  is a side elevation view of the implant holder coupled to the intervertebral implant illustrated in  FIG. 4B ; 
           [0020]      FIG. 5  a top view of an exemplary implementation of an implant holder sleeve (or guide member) utilized by several implant holder embodiments disclosed herein; 
           [0021]      FIG. 6  a top view of an exemplary implementation of an implant holder shaft (or rotation member) utilized by several implant holder embodiments disclosed herein; 
           [0022]      FIG. 7  is a top view of the shaft of  FIG. 6  translationally and rotationally coupled with the sleeve of  FIG. 5 ; 
           [0023]      FIG. 8A  is top view of the sleeve and shaft combination of  FIG. 7  coupled to the clamp and implant combination of  FIGS. 4B and 4C  in an unlocked configuration; 
           [0024]      FIG. 8B  is top view of the distal end of the sleeve and shaft combination coupled to the clamp and implant combination in the unlocked configuration illustrated in  FIG. 8A ; 
           [0025]      FIG. 9A  is perspective view of the implant and the distal end of the implant holder (comprising the clamp, sleeve, and shaft) of  FIGS. 8A and 8B  in a locked configuration; 
           [0026]      FIG. 9B  is top view of the implant and the distal end of the implant holder (comprising the clamp, sleeve, and shaft) in the locked configuration illustrated in  FIG. 9A ; 
           [0027]      FIG. 10A  is a perspective view of an exemplary implementation of an implant holder emplacement stop system utilized by certain implant holder embodiments disclosed herein; 
           [0028]      FIG. 10B  is a side elevation view of the exemplary implementation of the stop system of  FIG. 10A ; 
           [0029]      FIG. 10C  is a top elevation view of the exemplary implementation of the stop system of  FIGS. 10A and 10B ; 
           [0030]      FIG. 11A  is a perspective view of the exemplary implementation of an implant holder emplacement stop system of  FIGS. 10A ,  10 B, and  10 C connectively coupled to the top side of the implant holder sleeve of  FIG. 5 ; 
           [0031]      FIG. 11B  is a perspective view of the exemplary implementation of an implant holder emplacement stop system of  11 A in an alternative configuration connectively coupled to the bottom side of the implant holder sleeve; 
           [0032]      FIG. 11C  is a perspective view of the proximal end of the stop system illustrated in  FIG. 11A ; and 
           [0033]      FIG. 12  is an operational flow diagram illustrating a method for emplacing an implant using certain embodiments of the implant holder disclosed herein. 
       
    
    
     DETAILED DESCRIPTION 
       [0034]    Certain terminology is used in the following description for convenience only and is not limiting. The words “right”, “left”, “lower”, and “upper” designate direction in the drawings to which reference is made. The words “inner”, “outer” refer to directions toward and away from, respectively, the geometric center of the described feature or device. The words “distal” and “proximal” refer to directions taken in context of the item described and, with regard to the instruments herein described, are typically based on the perspective of the surgeon using such instruments. The words “anterior”, “posterior”, “superior”, “inferior”, “medial”, “lateral”, and related words and/or phrases designate preferred positions and orientation in the human body to which reference is made. The terminology includes the above-listed words, derivatives thereof, and words of similar import. 
         [0035]    In addition, various components are described herein as extending horizontally along a longitudinal direction “L” and lateral direction “A”, and vertically along a transverse direction “T”. Unless otherwise specified herein, the terms “lateral”, “longitudinal”, and “transverse” are used to describe the orthogonal directional components of various items. It should be appreciated that while the longitudinal and lateral directions are illustrated as extending along a horizontal plane, and that the transverse direction is illustrated as extending along a vertical plane, the planes that encompass the various directions may differ during use. For instance, when an implant is emplaced into an intervertebral space, the transverse direction T extends generally along the superior-inferior (or caudal-cranial) direction, while the plane defined by the longitudinal direction L and the lateral direction A lie generally in the anatomical plane defined by the anterior-posterior direction and the medial-lateral direction. Accordingly, the directional terms “vertical” and “horizontal” are used to describe the components merely for the purposes of clarity and illustration and are not meant to be limiting. 
         [0036]      FIG. 1A  is a perspective view of a pair of vertebral bodies  12   a  and  12   b  separated by an intervertebral space  14 .  FIG. 1B  is a side elevation view illustrating the insertion of an intervertebral implant  10  into the intervertebral space  14  between the two vertebral bodies  12   a  and  12   b  of  FIG. 1A .  FIG. 1C  is a perspective view of the vertebral bodies  12   a  and  12   b  of  FIGS. 1A and 1B  with the intervertebral implant  10  inserted into the intervertebral space  14 . 
         [0037]    Referring to  FIGS. 1A ,  1 B, and  1 C (collectively referred to herein as “FIG.  1 ”), a superior vertebral body  12   a  defines a superior vertebral surface  15   a  of an intervertebral space  14 , and an adjacent inferior vertebral body  12   b  defines an inferior vertebral surface  15   b  of the intervertebral space  14 . The intervertebral space  14  may be created by a discectomy where the disc material (not shown) normally found between the two vertebral bodies  12   a  and  12   b  has been removed to prepare the intervertebral space  14  to receive an orthopedic implant such as, for example, the intervertebral implant  10 . 
         [0038]    During operation the implant  10  is aligned with the intervertebral space  14 . The vertebral bodies  12   a  and  12   b  are retracted such that the anterior ends  96  of the vertebral bodies are separated generally along the caudal-cranial dimension a distance greater than the posterior ends  98  of the vertebral bodies  12   a  and  12   b  are separated. The implant  10  may then be inserted into the intervertebral space  14  to achieve restoration of “height” (that is, anatomically correct separation of the superior vertebral surface  15   a  from inferior vertebral surface  15   b ) while maintaining mobility. 
         [0039]      FIG. 2A  is a perspective view of the intervertebral implant  10  illustrated in  FIG. 1B  which includes first and second endplates ( 20  and  22  respectively) together forming an articulation disposed between the endplates.  FIG. 2B  is a side elevation view of the intervertebral implant illustrated in  FIG. 2A . 
         [0040]    Referring now to  FIGS. 2A and 2B  (collectively referred to herein as “FIG.  2 ”), and with reference to  FIG. 1 , the implant  10  may include a first or upper component, such as a first or upper endplate  20  adapted to engage the superior vertebral body  12   a , and a second or lower component, such as a second or lower endplate  22  adapted to engage the inferior vertebral body  12   b . The endplates  20  and  22  each carry complementary first and second joint members  75  and  77 , respectively, that provide rounded mating surfaces (concave for joint member  75  and convex for joint member  77 ) in operative contact with each other so as to provide an articulating joint that allows the endplates  20  and  22  360-degree universal movement relative to each other. The upper and lower endplates  20  and  22  can thus pivot relative to each other about a lateral axis, for instance to accommodate flexions and extensions of the vertebrae  12   a  and  12   b . Similarly, the upper and lower endplates  20  and  22  can pivot relative to each other about a longitudinal axis, for instance to accommodate lateral bending of the vertebrae  12   a  and  12   b . The pivot axis can also lie in any orientation within the horizontal plane defined by the longitudinal and lateral directions. 
         [0041]    In addition to the concave mating surfaces  75 , the upper endplate  20  also comprises an upper endplate body  21  that defines a longitudinally front end  23 , which provides a leading end with respect to insertion of the implant  10  into the intervertebral disc space  14 . The upper endplate body  21  further defines an opposing longitudinal rear end  25 , which provides a trailing end with respect to insertion of the implant  10  into the intervertebral disc space  14 . The upper endplate body  21  further defines opposing first and second lateral sides  27  and  29 , respectively, connected between the front and rear ends  23  and  25  respectively. The upper endplate body  21  further presents an upper (or outer) transverse bone facing surface  24 , and an opposing lower (or inner) transverse surface  43 . The upper endplate  20  includes a plurality of bone fixation spikes  39  projecting transversely outward, or up, from the bone facing surface  24  of the upper endplate body  21 . 
         [0042]    Similarly, in addition to the convex mating surfaces  77 , the lower endplate  22  also comprises a lower endplate body  37  that defines a longitudinally front end  47 , which provides a leading end with respect to insertion of the implant  10  into the intervertebral disc space  14 . The lower endplate body  37  further defines an opposing longitudinal rear end  31 , which provides a trailing end with respect to insertion of the implant  10  into the intervertebral disc space  14 . The lower endplate body  37  further defines opposing first and second lateral sides  33  and  35 , respectively, connected between the front and rear ends  47  and  31  respectively. The lower endplate body  37  further presents a lower (or outer) transverse bone facing surface  26 , and an opposing upper (or inner) transverse surface  45 . The lower endplate  22  includes a plurality of bone fixation spikes  41  projecting transversely outward, or down, from the bone facing surface  26  of the lower endplate body  37 . 
         [0043]    The front ends  23  and  47  of the endplates  20  and  22  define the front end  11  of the implant  10  corresponding to the posterior of the intervertebral space  14  for emplacement, while the rear ends  25  and  31  of the endplates  20  and  22  define the back end  13  of the implant  10  corresponding to the opposing anterior of the intervertebral space  14  for emplacement. Otherwise stated, the front end  11  is emplaced into the posterior region (proximate to posterior ends  98 ) of the intervertebral space  14  and the back end  13  is emplaced into the anterior region (proximate to anterior ends  96 ) of the intervertebral space  14 . 
         [0044]    To facilitate emplacement using an implant holder (various embodiments of which are described in detail later herein), the upper endplate  20  includes laterally opposing notches  85  that are external engagement features extending into the rear end  25  of the endplate body  21  that are sized and shaped to receive the upper portion of the distal end of an insertion tool (or implant holder) configured to insert the implant into an intervertebral space. The lower endplate  22  includes laterally opposing notches  87  extending into the rear end  31  of the endplate body  37  that are sized and shaped to receive the lower portion of an insertion tool configured to insert the implant  10  into an intervertebral space. 
         [0045]    As the implant  10  is inserted into the intervertebral space  14 , the spikes  39  and  41  initially slide freely into the intervertebral space  14 , and prior to full insertion begin to bite into the respective vertebral surfaces  15   a  and  15   b . Once the implant  10  has been fully inserted into the intervertebral space  14 , the retraction of the vertebral bodies  12   a  and  12   b  is released, thereby causing the surfaces  15   a  and  15   b  to return to their normal direction of extension, whereby the spikes  39  and  41  project into the vertebral surfaces  15   a  and  15   b.    
         [0046]    Since it may be challenging to manually handle the implant  10  because of its small size (e.g., less than ten millimeters wide, ten millimeters long, and only a few millimeters thick), a separate instrument—referred to as an implant holder or insertion tool—may be used to emplace the vertebral implant  10 . In general, the implant  10  is fixed to the implant holder, and then the surgeon directly manipulates the implant holder to emplace the implant  10  (without ever directly touching the implant in some embodiments). When the implant  10  is seemingly in place, the surgeon then uses X-rays to check position of the implant  10  (typically in profile) to see whether the implant  10  is properly placed or whether it must still be further maneuvered into a better position, and the surgeon adjusts the implants position as necessary by continuing to manipulate the implant holder. Once the desired emplacement of the implant  10  is seemingly achieved, the implant holder is then detached from the implant  10  and withdrawn, leaving behind the emplaced implant  10 . 
         [0047]    Various implant holders are disclosed herein comprise three functional components: a clamp, a sleeve, and a shaft. While these components are disclosed as distinct, separate, and interchangeable pieces that can be operatively coupled together for utilization, it will be readily understood and appreciated that these three functional components can also be formed as a single tool wherein the components are inseparable, or as a two-part tool wherein any two of the three operational components are formed as a single item. Similarly, an optional fourth component—an emplacement stop system—is also herein disclosed as a separate fourth piece for use with the implant holder but which can also be formed as part of the implant holder (namely the sleeve). Accordingly, nothing herein is intended to limit the embodiments described herein to separable components but, instead, a single formed piece may comprise one or more than one of the operational components described herein. 
         [0048]      FIG. 3A  is a perspective view of an exemplary implementation of an implant holder clamp  100  (or clamp) utilized by several implant holder embodiments disclosed herein.  FIG. 3B  is a top elevation view of the exemplary implementation of the clamp  100  of  FIG. 3A .  FIG. 3C  is a side elevation view of the exemplary implementation of the clamp  100  of  FIGS. 3A and 3B . 
         [0049]    Referring to  FIGS. 3A ,  3 B, and  3 C (collectively referred to herein as “FIG.  3 ”), the implant holder clamp  100  essentially comprises a U-shaped fork with two arms  102  and  104  fixedly coupled to a stem  106 . As illustrated, the stem  106  may comprise a substantially solid rod  110  with a shallow threaded hole  112  at the proximal end for attaching to the threaded end of a shaft. The stem is also fixedly coupled to each arm  102  and  104  proximate to a flexion hole  114 . The arms  102  and  104  are separated from each other by the flexion hole  114  and by a lateral gap  118  running from the flexion hole  114  to the distal end of the clamp  100 . Moreover, each arm  102  and  104  comprises a flexion portion  116 —in part formed by the flexion hole  114 —which provides the arms  102  and  104  with limited flexibility such that they can be moved toward or away from each other relative to their resting position (as illustrated) with the application of force (which also has the effect of decreasing or increasing the width of the lateral gap  118  running between the arms  102  and  104 ). 
         [0050]    The amount of force necessary to slightly separate the two arms  102  and  104  is dependent upon the thickness of the flexion portion  116  and the material from which the flexion portions (and, ostensibly, the entire stem) is made. For various embodiments disclosed herein, the amount of force required is low enough to enable a surgeon of ordinary strength and dexterity to affix an implant  10  onto the arms  102  and  104  of the implant holder clamp  100  as well as enable the implant  10  to detach and remain in position when emplaced in the intervertebral space  14  as the implant holder clamp  100  is withdrawn using a retraction force applied by the surgeon, but yet high enough to prevent the implant  10  from becoming inadvertently detached from the implant holder clamp  100  such as while the implant  10  is being emplaced in a forward longitudinal direction using the implant holder clamp  100 . This force is hereafter referred to as a “surgeon force” and an implant  10  that is attached and detached to an implant holder clamp  100  using surgeon force is said to be “loosely coupled.” In contrast, and as described later herein, when the implant cannot be decoupled from the implant holder using surgeon force, the implant is said to be “fixedly coupled.” 
         [0051]    Referring again to  FIG. 3 , each arm  102  and  104  further comprises a central body  120  featuring two of four clamping elements  132  (one superior and one inferior), half of a U-shaped central spacer  130 , and one of a pair of locking surfaces  126 . In normal operation, the four central-projecting clamping elements  132  are able to engage the notches  85  and  87  of the implant device  10  with the application of surgeon force as previously described. However, the locking surfaces  126  of each arm  102  and  104  enable the application of a locking force (for example, by operation of the shaft and sleeve discussed later herein) to fixedly couple the implant  10  to the clamp  100  by preventing the arms  102  and  104  from flexibly opening. Separately, the U-shaped central spacer  130  formed by both arms  102  and  104  semi-circumferentially abut against the convex joint member  77  of the articulating joint of the implant  10  as well as the upper and lower endplates  20  and  22  in order to maintain in parallel the lower (or inner) transverse surface  43  of the upper endplate  20  and the upper (or inner) transverse surface  45  of the lower endplate  22  to give temporary solidity to the implant  10  during its emplacement. 
         [0052]    In addition, each arm also comprises an optical control channel  122  on the upper surface of the arms  102  and  104  to enable the surgeon to visually gauge the location of the back end  13  of the implant  10  when the surgeon uses X-rays to check position of the implant  10  in profile (or laterally). For example, when the clamp  100  and the implant  10  are both made of radio-opaque materials (or any other situation where it is difficult to tell apart the implant  10  from the clamp  100  using X-rays), this optical control channel  122  provides an X-ray-visible feature that enables the surgeon to differentiate between the two components and better determine how far the back end  13  of the implant  10  is embedded (or “implanted” or “emplaced”) in the intervertebral space  14 . To this end, the optical control channel  122  may simply comprise a straight line-of-sight channel (with the arms in the resting position) or, alternatively, it may be coated or filled with X-ray reflective or deflective material to make it even more easily identified using an X-ray. Likewise, the channel may also be shaped differently—such as, for example, narrower medially but wider laterally to provide a less-specific by easier-to-identify reference point—and/or the clamp  100  may comprise more than one channel—such as, for example, a second optical control channel running on the lower endplate running parallel to the first optical control channel  122 . 
         [0053]      FIG. 4A  is a perspective view of the implant holder clamp  100  of  FIGS. 3A ,  3 B, and  3 C being coupled to an intervertebral implant  10  of  FIGS. 2A and 2B  (the latter still housed in sterile packaging  400 .  FIG. 4B  is a top view of the implant holder  100  coupled to the intervertebral implant  10  (and together removed from the sterile packaging  400  of  FIG. 4A ).  FIG. 4C  is a side elevation view of the implant holder  10  coupled to the intervertebral implant  10  illustrated in  FIG. 4B . Referring to  FIGS. 4A ,  4 B, and  4 C (collectively referred to herein as “FIG.  4 ”), the implant  10  is removed from its sterile packing longitudinally moving the implant holder  100  with surgeon force to loosely couple with the implant and then retracting the implant holder  100  and the implant  10  from the packaging—which, as illustrated, may be accomplished without the person performing the coupling directly touching the implant  10 . With particular reference to  FIG. 4B , it should be noted that the left edge of the optical control channel  122  of the implant holder  100  is substantially aligned with the back end  13  of the implant  10  such that the back end  13  of the implant can be accurately determined by locating the optical control channel  122  during the surgeon&#39;s aforementioned X-ray checks. 
         [0054]      FIG. 5  a top view of an exemplary implementation of an implant holder sleeve (or guide member)  200  utilized by several implant holder embodiments disclosed herein. Referring to  FIG. 5 , the sleeve  200  comprises a hollow body  210  featuring, at its proximal end, an attachment surface  240 , a service collar  212 , and the proximal opening of the hollow channel  214  running the length of the sleeve  200 . The attachment surface  240  may be used for mounting supplemental devices to the sleeve  200  (such as the stop system discussed later herein, for example). At the distal end, the hollow body  210  features a clamp coupler  216  which in turn comprises two locking tines  220  and the distal opening of the hollow channel  214  in a terminus surface  218 . The two locking tines  220  each comprise a locking surface  222  that are together geometrically angled to substantially match the geometric angle of the two locking surfaces  126  of the implant holder clamp  100 . 
         [0055]      FIG. 6  a top view of an exemplary implementation of an implant holder shaft  300  (or rotation member) utilized by several implant holder embodiments disclosed herein. Referring to  FIG. 6 , the sleeve  200  comprises a rod  310  featuring, at its proximal end, an in-hole stabilizer  314 , a mating collar  312 , and a rotation knob  316 . At its distal end, the rod  210  further comprises a threaded post  318  for engaging the threaded hole  112  of the implant holder clamp  100 . 
         [0056]      FIG. 7  is a top view of the shaft  300  of  FIG. 6  translationally and rotationally coupled with the sleeve  200  of  FIG. 5 , such that the distal end of the shaft (featuring the threaded post  318 ) is inserted through the proximal opening of the hollow channel  214  and runs the length of the sleeve  200  to distal end, wherein the sleeve  200  circumferentially and encloses the distal and medial portions of the shaft  300 . 
         [0057]      FIG. 8A  is top view of the sleeve  200  and shaft  300  combination of  FIG. 7  (also referred to herein as the “locking mechanism”) coupled to the clamp  100  and implant  10  combination of  FIGS. 4B and 4C  in an unlocked configuration.  FIG. 8B  is top view of the distal end of the sleeve and shaft combination coupled to the clamp and implant combination in the unlocked configuration illustrated in  FIG. 8A . Referring to  FIGS. 8A and 8B  (collectively referred to herein as “FIG.  8 ”), the stem  110  (not shown) of the implant holder  100  movably resides in the distal opening of the hollow channel  214  proximate to the terminus surface  218  of the sleeve  200 , and the threaded hole  112  of the implant holder  100  is partially coupled to the threaded post  318  of the shaft  300 . As the shaft  300  continues to be rotated (via the rotation knob  316  in a tightening direction), the threaded post  318  will continue draw the stem  110  (not shown) into the hollow channel  214  and move the implant holder  100  and its pair of locking surfaces  126  closer and closer to the clamp coupler  216  and its locking surfaces  222 . As such, rotating the shaft  300  within the sleeve  200  permits the surgeon (or a skilled assistant) to selectively determine to lock or unlock the clamp  100  which, in turn, determines whether the implant  10  is fixedly coupled (when locked) or loosely coupled (when unlocked) to the clamp  100 . 
         [0058]      FIG. 9A  is perspective view of the implant  10  and the distal end of the implant holder (comprising the clamp  100 , sleeve  200 , and shaft  300 ) of  FIGS. 8A and 8B  in a locked configuration.  FIG. 8B  is top view of the implant  10  and the distal end of the implant holder (comprising the clamp  100 , sleeve  200 , and shaft  300 ) in the locked configuration illustrated in  FIG. 9A . Referring to  FIGS. 9A and 9B  (collectively referred to herein as “FIG.  9 ”), the stem  110  (not shown) of the implant holder  100  has been maximally retracted into the distal opening of the hollow channel  214  proximate to the terminus surface  218  of the sleeve  200  by rotation of the threaded post  318  via the rotation knob  316 . In this configuration, the implant holder&#39;s  100  pair of locking surfaces  126  are in direct contact with the clamp coupler&#39;s  216  locking surfaces  222  which, in turn, prevents the arms  102  and  104  (not shown) and their corresponding clamping elements  132  from flexibly opening and decoupling from the implant  10 —that is, the implant  10  is “locked” or fixedly coupled to the clamp  100  of the implant holder (i.e., in a “locked position”). As such, the surgeon may emplace, move, and even withdraw the implant  10  and implant holder clamp  100  using surgeon force without leaving the implant  10  behind (as would be the case in an unlocked configuration) or risking the implant  10  from becoming inadvertently decoupled from the clamp  100 . 
         [0059]    To unlock the implant  10  from the clamp  100 —such as when the surgeon has satisfactorily emplaced the implant  10  into the intervertebral space  14 , for example—the surgeon merely rotates the shaft  200  in a loosening direction opposite the tightening direction (via the rotation knob  316 ) to separate the locking surfaces  126  of the implant holder clamp  100  from the locking surfaces  222  of the implant holder sleeve  200  and again return to a configuration akin to that shown in  FIG. 8 , in which instance the implant  10  is again only loosely coupled to the clamp  100  and can be removed by surgeon force from the clamp  100 . 
         [0060]      FIG. 10A  is a perspective view of an exemplary implementation of an implant holder emplacement stop system  500  utilized by certain implant holder embodiments disclosed herein.  FIG. 10B  is a side elevation view of the exemplary implementation of the stop system  500  of  FIG. 10A .  FIG. 10C  is a top elevation view of the exemplary implementation of the stop system of  FIGS. 10A and 10B . Referring to  FIGS. 10A ,  10 B, and  10 C (collectively referred to herein as “FIG.  10 ”), the stop system comprises a clip  502  for clipping to an attachment surface  240  of an implant holder sleeve  200  and rotatably mounting a threaded rotor  504  engaging the threaded proximal end  506 ′ of a stop body  506 . The distal end of the stop body  506  is coupled to a slidable sleeve  508  that, in turn, is coupled to a stop rod  510  ending in a stop surface  512  comprising the most distal end of the stop system  500 . For certain embodiments, the stop system  512  may be used to reduce risk of penetration into spinal canal during the implantation procedure. 
         [0061]      FIG. 11A  is a perspective view of the exemplary implementation of an implant holder emplacement stop system of  FIGS. 10A ,  10 B, and  10 C connectively coupled to the top side of the implant holder sleeve  200  of  FIG. 5 .  FIG. 11B  is a perspective view of the exemplary implementation of an implant holder emplacement stop system of  11 A in an alternative configuration connectively coupled to the bottom side of the implant holder sleeve.  FIG. 11C  is a perspective view of the proximal end of the stop system illustrated in  FIG. 11A . Referring to  FIGS. 11A ,  11 B, and  11 C (collectively referred to herein as “FIG.  11 ”), by rotating the threaded rotor  504  the surgeon can longitudinally move the stop  512  to correspond to a desired depth such that when used, the stop will abut up against the anterior surface of a vertebrae (such as superior vertebral body  12   a ) and prevent the implant  10  from being emplaced any deeper into the intervertebral space  14 . 
         [0062]      FIG. 12  is an operational flow diagram illustrating a method for emplacing an implant  10  using certain embodiments of the implant holder disclosed herein. Referring to  FIG. 12 , at  602  the surgeon (or a qualified assistant) couples the shaft  300  to the sleeve  200  by inserting the shaft  300  into the sleeve  200  as previously discussed herein. At  604 , the surgeon also couples (that is, loosely couples in an unlocked configuration) the clamp  100  to the implant  10 . At  606  the surgeon them coupled the clamp  100  and implant  10  combination to the sleeve  200  and shaft  300  combination (or “locking mechanism”) which initially is still in the unlocked configuration (or “unlocked position”). In an alternative approach, the surgeon could first couple the clamp, sleeve, and shaft in an unlocked configuration, and then couple this three-part assembly to the implant. In other words, there are several ways in which each of the clamp  100 , sleeve  200 , shaft  300 , and implant  10  are coupled, and thus the order presented in  FIG. 12  is only exemplary and is in no way limiting. 
         [0063]    At  608  the surgeon then locks the implant  10  into the implant holder by engaging the locking surfaces  126  of the clamp  100  with the locking surfaces  222  of the sleeve  200  and, at  610 , the surgeon then proceeds to emplace the implant  10  using the assembled implant holder (with or without the optional stop system  500 ). After emplacing the implant  10 , the surgeon then uses X-rays (and the optical control channel  122  as an X-ray-visible reference point) to determine if the implant is emplaced in a suitable location. If not (as determined at  614 ), at  624  the surgeon reiteratively re-emplaces the implant  10  by continuing to manipulate the implant  10  via the implant holder and, returning to  612 , checking implant  10  until it is properly emplaced. 
         [0064]    Once properly emplaced, at  616  the implant  10  and implant holder are unlocked and, at step  618 , the implant holder is withdrawn (or retracted) using surgeon force. At  620 , if the embedding of the implant  10  is stable, the implant should remain embedded and, if so, the surgeon can then conclude the embedding portion of the procedure. However, if the implant  10  is not stable and continues to be loosely coupled to the implant holder when withdrawn, then the surgeon needs to re-emplace the implant (or a different implant) at step  624  and continue again from there. 
         [0065]    As will readily appreciated by those of skill in the art, the various components described herein can be formed from a variety of biocompatible materials, such as cobalt chromium molybdenum (CoCrMo), titanium and titanium alloys, stainless steel or other metals, as well as ceramics or polymers such as polyetheretherketone (PEEK), polyetherketoneketone (PEKK), bioresorbable materials, and bonegraft (for example allograft and xenograft). A coating may be added or applied to the various components described herein to improve physical or chemical properties, or to help ensure bony in or on growth of medication. Examples of coatings include plasma-sprayed titanium coating or Hydroxypatite. Moreover, skilled artisans will also appreciate that the various components herein described can be constructed with any dimensions desirable for implantation of any intervertebral space along the spine and, in addition to use as a disc replacement device, are also readily configurable for use with a range of bone-anchored orthopedic prostheses, such as a spinal fusion implant, an interbody spacer, an intervertebral cage, a corpectomy device, hip and knee replacement implants, long bone replacement plates, intramedulary nails and rods, bone fixation plates (such as for fixation of craniomaxillofacial fractures), veterinary implants, and tips for guide wires, and the like. 
         [0066]    The subject matter described above is provided by way of illustration only and should not be construed as limiting. Various modifications and changes may be made to the subject matter described herein without following the example embodiments and applications illustrated and described, and without departing from the true spirit and scope of the present invention, which is set forth in the following claims.