Abstract:
A catheter holder designed to deliver a curable biomaterial to an intervertebral disc space. By securing the catheter to the catheter holder, the depth of insertion of the catheter into the disc space can be accurately controlled. The catheter holder optionally helps with insertion of a optional mold through the annulotomy and into the disc space created by the nuclectomy. The catheter holder helps keep the mold from being drawn too far into the disc space or pushed too far out of the disc space during polymer injection.

Description:
[0001]     The present application claims the benefit of U.S. Provisional Application Ser. No. 60/677,273 entitled Catheter Holder for Spinal Implants filed May 3, 2005; U.S. Provisional Application Ser. No. 60/708,245 entitled Catheter Holder for Spinal Implants filed Aug. 15, 2005; U.S. Provisional Application Ser. No. 60/708,244 entitled Multi-Lumen Mold For Intervertebral Prosthesis And Method Of Using Same filed on Aug. 15, 2005, all of which are hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to a method and apparatus for filling an intervertebral disc space with an in situ curable biomaterial using a catheter holder to releasably secure the delivery mechanism to the patient.  
       BACKGROUND OF THE INVENTION  
       [0003]     The intervertebral discs, which are located between adjacent vertebrae in the spine, provide structural support for the spine as well as the distribution of forces exerted on the spinal column. An intervertebral disc consists of three major components: cartilage endplates, nucleus pulposus, and annulus fibrosus. The central portion, the nucleus pulposus or nucleus, is relatively soft and gelatinous; being composed of about 70 to 90% water. The nucleus pulposus has a high proteoglycan content and contains a significant amount of Type II collagen and chondrocytes. Surrounding the nucleus is the annulus fibrosus, which has a more rigid consistency and contains an organized fibrous network of approximately 40% Type I collagen, 60% Type II collagen, and fibroblasts. The annular portion serves to provide peripheral mechanical support to the disc, afford torsional resistance, and contain the softer nucleus while resisting its hydrostatic pressure.  
         [0004]     Intervertebral discs, however, are susceptible to a number of injuries. Disc herniation occurs when the nucleus begins to extrude through an opening in the annulus, often to the extent that the herniated material impinges on nerve roots in the spine or spinal cord. The posterior and posterio-lateral portions of the annulus are most susceptible to attenuation or herniation, and therefore, are more vulnerable to hydrostatic pressures exerted by vertical compressive forces on the intervertebral disc. Various injuries and deterioration of the intervertebral disc and annulus fibrosus are discussed by Osti et al., Annular Tears and Disc Degeneration in the Lumbar Spine,  J. Bone and Joint Surgery,  74-B( 5 ), (1982) pp. 678-682; Osti et al., Annulus Tears and Intervertebral Disc Degeneration,  Spine,  15(8) (1990) pp. 762-767; Kamblin et al., Development of Degenerative Spondylosis of the Lumbar Spine after Partial Discectomy,  Spine,  20(5) (1995) pp. 599-607.  
         [0005]     Many treatments for intervertebral disc injury have involved the use of nuclear prostheses or disc spacers. A variety of prosthetic nuclear implants are known in the art. For example, U.S. Pat. No. 5,047,055 (Bao et al.) teaches a swellable hydrogel prosthetic nucleus. Other devices known in the art, such as intervertebral spacers, use wedges between vertebrae to reduce the pressure exerted on the disc by the spine. Intervertebral disc implants for spinal fusion are known in the art as well, such as disclosed in U.S. Pat. Nos. 5,425,772 (Brantigan) and U.S. Pat. No. 4,834,757 (Brantigan).  
         [0006]     Further approaches are directed toward fusion of the adjacent vertebrate, e.g., using a cage in the manner provided by Sulzer. Sulzer&#39;s BAK® Interbody Fusion System involves the use of hollow, threaded cylinders that are implanted between two or more vertebrae. The implants are packed with bone graft to facilitate the growth of vertebral bone. Fusion is achieved when adjoining vertebrae grow together through and around the implants, resulting in stabilization.  
         [0007]     Apparatuses and/or methods intended for use in disc repair have also been described but none appear to have been further developed, and certainly not to the point of commercialization. See, for instance, French Patent Appl. No. FR 2 639 823 (Garcia) and U.S. Pat. No. 6,187,048 (Milner et al.). Both references differ in several significant respects from each other and from the apparatus and method described below. For instance, neither reference teaches switching the flow of biomaterial between discrete operating parameters or methods of detecting ruptures in the mold. Further, neither reference teaches shunting an initial portion of a curing biomaterial in the course of delivering the biomaterial to the disc space.  
         [0008]     Prosthetic implants formed of biomaterials that can be delivered and cured in situ, using minimally invasive techniques to form a prosthetic nucleus within an intervertebral disc have been described in U.S. Pat. No. 5,556,429 (Felt) and U.S. Pat. No. 5,888,220 (Felt et al.), and U.S. Patent Publication No. US 2003/0195628 (Felt et al.), the disclosures of which are incorporated herein by reference. The disclosed method includes, for instance, the steps of inserting a collapsed mold apparatus (which in a preferred embodiment is described as a “mold”) through an opening within the annulus, and filling the mold to the point that the mold material expands with a flowable biomaterial that is adapted to cure in situ and provide a permanent disc replacement. Related methods are disclosed in U.S. Pat. No. 6,224,630 (Bao et al.), entitled “Implantable Tissue Repair Device” and U.S. Pat. No. 6,079,868 (Rydell), entitled “Static Mixer”, the disclosures of which are incorporated herein by reference.  
       BRIEF SUMMARY OF THE INVENTION  
       [0009]     The present invention relates to a method and apparatus for filling an intervertebral disc space with an in situ curable biomaterial using a catheter holder to releasably secure the delivery mechanism to the patient. The present catheter holder can be used, for example, to implant a prosthetic total disc, or a prosthetic disc nucleus, using minimally invasive techniques that leave the surrounding disc tissue substantially intact. The phrase intervertebral disc prosthesis is used generically to refer to both of these variations.  
         [0010]     Minimally invasive refers to a surgical mechanism, such as microsurgical, percutaneous, or endoscopic or arthroscopic surgical mechanism, that can be accomplished with minimal disruption of the pertinent musculature, for instance, without the need for open access to the tissue injury site or through minimal incisions (e.g., incisions of less than about 4 cm and preferably less than about 2 cm). Such surgical mechanism are typically accomplished by the use of visualization such as fiber optic or microscopic visualization, and provide a post-operative recovery time that is substantially less than the recovery time that accompanies the corresponding open surgical approach.  
         [0011]     The present catheter holder is designed to position and secure the catheter in the desired position in an intervertebral disc space during and following polymer injection. The present catheter holder can be used to inject biomaterial with or without a mold.  
         [0012]     In embodiments using a mold, the present catheter holder helps with insertion of the mold through the annulotomy and into the disc space created by the nuclectomy. By securing the catheter to the present catheter holder, the depth of insertion of the mold into the disc space can be accurately controlled during the delivery of biomaterial. In particular, the present catheter holder helps keep the mold from being drawn too far into the disc space or pushed too far out of the disc space during polymer injection. The present catheter holder can also receive other devices, such as a catheter cutter that cuts the catheter to the desired depth, imaging devices, and the like.  
         [0013]     In one embodiment, the catheter holder includes a member having at least one catheter channel, a proximal end and a distal end. A mounting flange is attached near the proximal end of the member. In one embodiment, the mounting flange is connected, directly or indirectly, to a secondary holding device.  
         [0014]     A surgical tool is preferably attached near the distal end of the member. In one embodiment, the surgical tool limits the depth of insertion into the intervertebral disc space. For example, the surgical tool may have a cross-sectional area greater than the cross-sectional area of the distal end of the member. The surgical tool is optionally releasably attached to the member. In one embodiment, a plurality of surgical tools having different geometric features from which the surgeon can select are provided.  
         [0015]     In another embodiment, the surgical tool is a nerve guard ring or a blood vessel retractor. The nerve guard ring preferably has an asymmetrical support surface. The surgical tool can also serve to support the annulus during injection of the biomaterial. In one embodiment, the surgical tool is both a nerve guard ring and a support structure for the annulus. In another embodiment, the surgical tool is a support structure is delivered through the catheter to a located inside the annulus. After the biomaterial is delivered and/or at least partially cured, the support structure is removed through the catheter. Alternatively, the support structure can be detached from the member and retained in the annulus. In one embodiment, the support structure is bio-resorbable.  
         [0016]     The member is preferably a hollow structure in fluid communication with the catheter channel. In one embodiment, the member includes an aperture in a side that is fluidly coupled to the catheter channel. The aperture is preferably configured to direct the catheter into the catheter channel at an acute angle.  
         [0017]     A securing mechanism is provided that secures a catheter extending through the catheter channel to the catheter holder. In one embodiment, the securing mechanism is a catheter locking pin sized to fit into the catheter channel. The catheter locking pin has a distal end configured to compressively secure a catheter in the catheter channel. The catheter locking pin can optionally include a spring portion. In another embodiment, the securing mechanism is a compression fitting adapted to secure a catheter in the catheter channel.  
         [0018]     The present invention is also directed to a catheter holder that can be secured to the patient with or without a secondary holding device. In one embodiment, an outer tube surrounds the catheter. A flexible material attaches the distal end of the catheter to the distal end of the outer tube. Displacement of the outer tube toward the distal end of the catheter causes the flexible material to expand outwardly away from the catheter. The expanded structure can be located in the annulotomy, inside the annulus, outside the annulus, or a combination thereof.  
         [0019]     In another embodiment, the catheter holder includes an expandable bladder located near at least the distal end of the tubular member. A delivery tube is fluidly coupled to the expandable bladder. Again, the expanded bladder can be located in the annulotomy, inside the annulus, outside the annulus, or a combination thereof. In one embodiment, the expandable bladder is attached directly to a balloon catheter. In another embodiment, a sheath extends around a portion of the expandable bladder to limit the location and/or amount of expansion.  
         [0020]     The present invention is also directed to an expandable coiled material located near the distal end of a tubular member. The proximal end of the expandable coiled material is attached to the tubular member near the distal end of the tubular member. The expandable coiled material has an outer diameter that contracts when a force directed away from the tubular member is applied to the distal end of the expandable coiled material. In operation, a tension force is applied to the coiled materials so it contracts around the catheter. The contracted coiled material is inserted into the annulotomy. The tension force is then release so the coiled material expands into the annulotomy, to secure the catheter thereto. When the procedure is competed, the tension force is again applied to the distal end of the coiled material to permit removal from the annulotomy.  
         [0021]     The present method and apparatus include a radiopaque portion on the catheter holder to assist in imaging the position of the mold in the intervertebral disc space before, during and/or after delivery of biomaterial. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0022]      FIG. 1  is an exemplary catheter and mold in accordance with the present invention.  
         [0023]      FIG. 2  is a side view of a catheter holder in accordance with the present invention.  
         [0024]      FIG. 3  is a top view of an extension on the catheter holder of  FIG. 2 .  
         [0025]      FIG. 4  is an enlarged view of a cut-out in the member of  FIG. 2 .  
         [0026]      FIG. 5  is a longitudinal-sectional view of an alternate cut-out in the member of  FIG. 2 .  
         [0027]      FIG. 6  is an enlarged view of the member of  FIG. 2 .  
         [0028]      FIG. 7  is a bottom view of the member of  FIG. 6 .  
         [0029]      FIG. 8  is a top view of an alternate catheter holder in accordance with the present invention.  
         [0030]      FIG. 9  is a side view of the catheter holder of  FIG. 8 .  
         [0031]      FIGS. 10 and 11  are side views of an alternate core with a spring region for use with the catheter holder of the present invention.  
         [0032]      FIGS. 12 and 13  are front and side views of an alternate catheter holder in accordance with the present invention.  
         [0033]      FIG. 14  is a side view of an alternate catheter holder in accordance with the present invention.  
         [0034]      FIG. 15  is a side view of an alternate catheter holder in accordance with the present invention.  
         [0035]      FIG. 16  is a side view of an alternate catheter holder in accordance with the present invention.  
         [0036]      FIGS. 17A and 18A  are side views of an alternate catheter holder engaged with the annulotomy in accordance with the present invention.  
         [0037]      FIGS. 17B and 18B  are side views of an alternate catheter holder engaged above the annulotomy in accordance with the present invention.  
         [0038]      FIGS. 19A and 20A  are side views of an alternate catheter holder engaged with the annulotomy in accordance with the present invention.  
         [0039]      FIGS. 19B and 20B  are side views of an alternate catheter holder engaged with the annulotomy in accordance with the present invention.  
         [0040]      FIG. 20C  is an enlarged side view of an expandable catheter holder positioned to straddle the annulotomy in accordance with the present invention.  
         [0041]     FIGS.  21  is a cross-sectional view of an intervertebral disc with an alternate catheter holder in accordance with the present invention.  
         [0042]      FIG. 22  is a cross-sectional view of an intervertebral disc with an alternate catheter holder in accordance with the present invention.  
         [0043]      FIG. 23  is a side view of the strap of  FIG. 22 .  
         [0044]      FIG. 24  is a cross-sectional view of an intervertebral disc with an alternate catheter holder in accordance with the present invention.  
         [0045]      FIG. 25  is a top view of the surgical tool of  FIG. 24 .  
         [0046]      FIG. 26  is a side view of the surgical tool of  FIG. 24 .  
         [0047]      FIG. 27  is a front view of the catheter holder of  FIG. 24 .  
         [0048]      FIG. 28  is a side view of the catheter holder of  FIG. 24 .  
         [0049]      FIG. 29  is a top view of an alternate surgical tool in accordance with the present invention.  
         [0050]      FIG. 30  is a side view of the surgical tool of  FIG. 29 .  
         [0051]      FIGS. 31-33  illustrate various views of an alternate mounting flange in accordance with the present invention.  
         [0052]      FIG. 34  is a side view of a surgical tool insertion tool in accordance with the present invention.  
         [0053]      FIG. 35  illustrates a cross-sectional view of an intervertebral disc of an alternate catheter holder in accordance with the present invention.  
         [0054]      FIG. 36  is a side sectional view of an alternate catheter holder in accordance with the present invention.  
         [0055]      FIG. 37  is a cross-sectional view of the catheter holder of  FIG. 36  engaged with an annulus. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0056]      FIG. 1  illustrates an exemplary catheter  11  with mold or balloon  13  located on the distal end for use with the catheter holders of the present invention. In the illustrated embodiment, biomaterial  23  is delivered to the mold  13  through the catheter  11 . Secondary tube  11 ′ evacuates air from the mold  13  before, during and/or after the biomaterial  23  is delivered. The secondary tube  11 ′ can either be inside or outside the catheter  11 , or can enter the mold  13  from another side, such as in a multi-lumen mold. Various multi-lumen molds are disclosed in commonly assigned U.S. patent application Ser. No. ______, entitled Multi-Lumen Mold For Intervertebral Prosthesis And Method Of Using Same filed on the same date herewith (Attorney Docket No. 321297), which is hereby incorporated by reference. Alternatively, the catheter holder of the present invention can be used to inject biomaterial directly into the annulus of a patient, without the use of the mold or balloon  13 .  
         [0057]     Surgical tool  25  is located on the catheter  11 . In the illustrated embodiment, the surgical tool  25  is a stop that limits the depth of insertion of the mold  13  into the annulus (see e.g.,  FIG. 2 ). The location of the stop  25  on the catheter  11  can either be fixed or adjustable. In one embodiment, the stop  25  includes a slip-fit mechanism to permit it to be moved to different locations along the catheter  11 .  
         [0058]      FIGS. 2-7  illustrate a first embodiment of a catheter holder  30  in accordance with the present invention. In the illustrated embodiment, the catheter holder  30  includes a member  32  with a mounting flange  34  on a proximal end  36  and a surgical tool  38  on a distal end  40 . The member  32  is preferably rigid or semi-rigid. The member  32  includes a catheter channel  42  adapted to receive catheter  44 . In an alternate embodiment, the mounting flange can be attached to the member  32  at a variety of locations. The member  32  can be constructed from a variety of radiopaque or radiolucent materials, such as metal, plastic or a variety of composites. In one embodiment, the member  32  is constructed from a radio-translucent plastic.  
         [0059]     In the illustrated embodiment, the mounting flange  34  is attached to a secondary holding device  46  that is preferably attached, directly or indirectly through additional components, to some fixed structure, such as an operating table. In another embodiment, the secondary holding device  46  can include a handle that is gripped by a member of the operating staff to hold the catheter holder  30  in the desired location. In yet another alternate embodiment, the secondary holding device  46  is attached, directly or indirectly through additional components, to the patient, such as for example, using a retractor, Steinmann pins, a harness fitted to the patient, or a variety of other devices.  
         [0060]     As used herein, “secondary holding device” refers to a mechanism that can be, directly or indirectly through additional components, releasably attached to the patient, releasably attached to an external structure, gripped by the surgical staff, or any combination thereof. The secondary holding device  46  preferably that limits movement of the catheter holder  30  along at least the z-axis  68 , and more preferably along the x-axis, y-axis and z-axis. Although  FIG. 2  illustrates the secondary holding device  46  attached near the proximal end  36 , the secondary holding device  46  can attach to the catheter holder  30  anywhere along the exposed or accessible portion of the member  32 .  
         [0061]     The proximal end  36  of the member  32  includes an opening  33  that communicates with the catheter channel  42 . The proximal end  36  can be used as an access port for performing other steps in the procedure. For example, the proximal end  36  can be used as a guide for performing the annulotomy  91  (aperture in the annulus  86 ); performing the nuclectomy (removal of nucleus material  98 ); evaluating the nuclectomy or the annulus  86 ; imaging the annulus  86 ; implanting the mold  13 ; delivering the biomaterial; and/or cutting the catheter  44  as close to the neck of the mold  13  as possible. Disclosure related to evaluating the nuclectomy or the annulus is found in U.S. patent application Ser. No. 10/984,493, entitled “Multi-Sage Biomaterial Injection System for Spinal Implants, which is incorporated by reference.  
         [0062]     The present invention is suitable for accessing the annulus  86  from any of the available access directions, including posterior, posterior lateral, lateral, anterior, or anterolateral. For procedures using the anterior approach, the distal end  40  is preferably longer than used for the posterior approaches.  
         [0063]     In the illustrated embodiment, the mounting flange  34  also includes extension  48  designed to releaseably engage with the catheter  44 . As best illustrated in  FIG. 3 , the extension  48  in the present embodiment includes a slot  50  which is sized to loosely guide or to compressively engage with the catheter  44 . In one embodiment, the slot  50  forms a friction fit with the catheter  44 .  
         [0064]     In the illustrated embodiment, the surgical tool  38  has a cross-sectional area greater than the cross-sectional area of the distal end  40  of the member  32 . The surgical tool  38  of  FIG. 2  is adapted to limit the depth of insertion of the member  32  into the annulus  86 . In the illustrated embodiment, the surgical tool  38  positions the member  32  against the annulus  86 . The surgical tool  38  can optionally serve as a nerve guard ring, a blood vessel retractor, and/or a tamp or support structure for the annulus  86  during injection of the biomaterial, as will be discussed in greater detail below.  
         [0065]     As used herein, “surgical tool” refers to one or more of a stop, a tamp or support structure, a blood vessel retractor, and/or a nerve guard ring that attaches near distal end of the member of the present catheter holder. The stop limits the depth of insertion of the catheter into the annulus. The tamp or support structure typically supports an annulus during and/or after delivery of biomaterial. The blood vessel retractor is typically used for anterior or anterolateral entry. The nerve guard ring is typically used for posterior or posterolateral entry. The surgical tools are preferably interchangeable, permitting the surgeon to select one or more while performing the procedure. Various embodiments of the surgical tool are disclosed herein.  
         [0066]     As best illustrated in  FIGS. 6 and 7 , the nerve guard ring  52  includes a support surface  54  with an opening  56  along a portion of its perimeter  58 . The nerve guard ring  52  preferably can rotate around the distal end  40  of the member  32 , thereby eliminating the need for right-hand and left-hand versions of the present catheter holder  30 .  
         [0067]     The position of the nerve guard ring  52  along the distal end  40  of the member  32  is preferably adjustable. In one embodiment, the nerve guard ring  52  can move a distance “d” to adjust how far the distal end  40  penetrates into the annulus  86 . By adjusting the position of the nerve guard ring  52 , the surgeon can precisely control how far bottom edge  41  of the member  32  penetrates into the annulus  86 . The bottom edge  41  then can be used as a reference surface or datum for positioning the catheter  44  relative to the catheter holder  30 , and in particular, for positioning the optional mold  90  in the cavity  84 .  
         [0068]     In the illustrated embodiment, the bottom edge  41  of the member  32  has a contour corresponding to the desired shape of the implant. As the mold  90  is filed with biomaterial, it expands against the bottom edge  41 , causing it and biomaterial  23  to conform to the shape of the bottom edge  41 . When the biomaterial is cured, it will retain the shape of the bottom edge  41 . Alternatively, the bottom edge  41  can be flat or a variety of other shapes.  
         [0069]     Turning back to  FIG. 2 , an annulotomy or opening  91  is formed in the annulus  86  of intervertebral disc  64  located between opposing vertebrate  82 . The surgical tool  38  limits how far the member  32  penetrates into the patient  60 , and in particular, into the annulus  86  and the cavity  84  formed by the nuclectomy. The intervertebral disc  64  and/or tissue  62  adjacent to the intervertebral disc  64  provides a force  66  acting on the surgical tool  38  that limits movement of the catheter holder  30  along the z-axis  68 . The tissue surrounding the distal end  40  assists in limiting movement of the distal end  40  along the x-axis and y-axis that intersect the distal end  40 .  
         [0070]     The secondary holding device  46  limits movement of the proximal end  36  of the catheter holder  30  along the z-axis  68  and preferably along the x-axis and y-axis that intersects the proximal end  36 . In one embodiment, the secondary holding device  46  provides a counter acting force  70  generally along the z-axis. In the illustrated embodiment, the forces  66  and  70  assist in retaining the catheter holder  30  relative to the patient  60 .  
         [0071]     In one embodiment, the member  32  is preferably sufficiently rigid so as to not bend or buckle when subjected to the forces  66  and  70 . In another embodiment, the member  32  bends elastically a small amount when subjected to the forces  66  and  70  to applying more constant pressure on the patient  60 . In the illustrated embodiment, the forces  66  and  70  are parallel and opposing. In another embodiment, the forces  66  are  70  are co-axial. The forces  66 ,  70  do not need to be co-axial or parallel to secure the catheter holder  30  to the patient  60 . For example, the forces  66 ,  70  can be at an acute angle relative to each other.  
         [0072]     In the illustrated embodiment, member  32  is a hollow tube with a cut-out  72  near the distal end  40 . The cut-out  72  is preferably located on the same side of the member  32  as the extension  48 . The catheter  44  is inserted into cut-out  72 , preferably at an acute angle, through the catheter channel  42  and into the intervertebral disc  64  of the patient  60 . Since the position of the catheter holder  30  is fixed relative to the patient  60 , the depth to which the catheter  44  penetrates into cavity  84  formed in the annulus  86  can be set and fixed by securing the catheter  44  to the catheter holder  30 .  
         [0073]     In one embodiment, the catheter  32  is secured to the slot  50  of the extension  48 . In another embodiment, catheter locking pin or core  92  is inserted along the z-axis  68  into the proximal end  36  of the catheter holder  30 . The tapered tip  94  of the core  92  compresses the catheter  44  against edge  100  in the cut-out  72 . In one embodiment, the tapered tip  94  may include a cutting edge. The core  92  can be fixedly engaged with the catheter holder  30  using a cap  93  that has threads that mate with threads  106  on the proximal end  36 . The cap  93  can be used to set the proper locking tension on the catheter  44 .  
         [0074]     Once the catheter  44  is maneuvered along catheter channel  42  to the proper depth within the intervertebral disc  64 , biomaterial is delivered through the catheter  44  to mold  90  located in the cavity  84  or directly into the cavity  84  formed in the annulus  86 . Various implant procedures, implant molds, and biomaterials related to intervertebral disc replacement suitable for use with the present invention are disclosed in U.S. Pat. No. 5,556,429 (Felt); U.S. Pat. No. 6,306,177 (Felt, et al.); U.S. Pat. No. 6,248,131 (Felt, et al.); U.S. Pat. No. 5,795,353 (Felt); U.S. Pat. No. 6,079,868 (Rydell); U.S. Pat. No. 6,443,988 (Felt, et al.); U.S. Pat. No. 6,140,452 (Felt, et al.); U.S. Pat. No. 5,888,220 (Felt, et al.); U.S. Pat. No. 6,224,630 (Bao, et al.), and U.S. patent application Ser. Nos. 10/365,868 and 10/365,842, all of which are hereby incorporated by reference.  
         [0075]     In some embodiments, the annulus  86  can itself serve as a suitable mold for receiving the biomaterial. Optionally, the interior surface of the annular shell can be treated or covered with a suitable material in order to enhance its integrity and use as a mold. Although the embodiments herein disclose the use of a mold mounted on the end of the catheter, the present catheter holders are equally applicable to the delivery of biomaterial directly into the annulus.  
         [0076]     The catheter holder and method of the present invention can also be used to repair other joints, including diarthroidal and amphiarthroidal joints. Examples of suitable diarthroidal joints include the ginglymus (a hinge joint, as in the interphalangeal joints and the joint between the humerus and the ulna); throchoides (a pivot joint, as in superior radio-ulnar articulation and atlanto-axial joint); condyloid (ovoid head with elliptical cavity, as in the wrist joint); reciprocal reception (saddle joint formed of convex and concave surfaces, as in the carpo-metacarpal joint of the thumb); enarthrosis (ball and socket joint, as in the hip and shoulder joints) and arthrodia (gliding joint, as in the carpal and tarsal articulations). The present catheter holders can also be used for a variety of other procedures, including those listed above.  
         [0077]     As best illustrated in  FIG. 4 , the cut-out  72  in the member  32  optionally includes a flared edge  100  designed to minimize damage to the catheter  44 .  FIG. 5  illustrates an alternate embodiment of the member  32  with an angled groove  102  located at the lower end of the cut-out  72 . The groove  102  preferably has a diameter slightly larger than the diameter of the catheter  44 . The cut-out  72  is preferably configured to create a smooth transition of the catheter  44  into the catheter channel  42 .  
         [0078]     The core  92  can optionally be used to cut the catheter  44  after the biomaterial is cured. In one embodiment, the core  92  is rotated or advanced further into the member  32 , severing catheter  44  and cured biomaterial at a location near the edge  100 . For example, the threads  106  can be used to advance the core  92  toward the edge  100 . Alternatively, the core  92  is removed and the catheter  44  is manually cut near the edge  100 .  
         [0079]      FIGS. 8 and 9  illustrate an alternate catheter holder  120  in accordance with the present invention. As best illustrated in  FIG. 8 , mounting flange  122  is offset from extension  124  by approximately 90 degrees. Extension  124  includes a slot  126  sized to receive a catheter. The catheter holder  120  includes a core  128  which is positioned in the center of the member  130 , as discussed above. Once the core  128  is positioned in the member  130 , bail  132  is rotated around pivot point  134  along the direction  136  to secure proximal end  138  of the core  128  within the member  130 . The tapered end  140  of the core  128  secures a catheter against the edge  142  of the cut-out  143 , as discussed above.  
         [0080]     Distal end  40  of the member  130  includes surgical tool  144  as discussed above. An optional radiopaque marker band  146  can be located on the distal end  40  of the member  130 . The radiopaque band  146  can optionally be used for imaging during the implant procedure.  
         [0081]      FIGS. 10 and 11  illustrate front and side views of an alternate core  150  for use in the member  130  of  FIG. 9 . The core  150  includes a spring region  152  that assists in applying more constant pressure on the catheter. In the illustrated embodiment, the spring region  152  is a serpentine or corrugated region formed in the core  150 . In an alternate embodiment, the core  150  can be a two-piece telescoping structure with an internal spring to provide a predictable spring force. The spring region  152  is particularly useful in accommodating for tolerances and materials when working with plastic parts.  
         [0082]      FIGS. 12 and 13  illustrate an alternate catheter holder  200  in accordance with the present invention. The catheter holder  200  includes a member  202  with an upper tubular member  204  and a lower tubular member  206 . Mounting flange  208  is preferably attached to the upper tubular member  204  or the member  202 . Surgical tool  210  is attached at the distal end  212  of the lower tubular member  206 . Catheter  214  is inserted through the tubular members  204  and  206  as discussed above. Tubular member  204  preferably includes a compression member  216  to secure the catheter  214  relative to the length of the catheter holder  200 .  
         [0083]      FIG. 14  illustrates an alternate catheter holder  250  in accordance with the present invention. The catheter holder  250  includes a curved member  252  with an upper tubular member  254  and a lower tubular member  256 . Mounting flange  258  is attached to the upper tubular member  254 . The mounting flange  258  preferably includes an opening  264  co-axially aligned with lower tubular member  256 . The opening  264  and the lower tubular member  256  are provided to receive and position other devices used in the implant procedure, such as imaging catheters, catheter cutters, and the like.  
         [0084]     Surgical tool  260  is attached to the lower tubular member  256 . Catheter  262  is inserted through the tubular members  254 ,  256  and into the patient as discussed above. Compression member  266  is preferably provided on the upper tubular member  254  to secure the catheter  262  relative to the length of the catheter holder  250 .  
         [0085]      FIG. 15  is a side view of an alternate catheter holder  300  in accordance with the present invention. Member  302  includes a tubular portion  304  on the proximal end  308  and tubular portion  306  on the distal end  310 . The tubular portions  304 ,  306  are provided to receive and position other devices used in the implant procedure, such as imaging catheters, catheter cutters, and the like.  
         [0086]     Mounting flange  312  is attached to the tubular member  304  on the proximal end. Surgical tool  314  is attached to the tubular member  306  on the distal end  310 . Catheter guide  316  is positioned at an angle relative to the member  302 . Extension  318  attaches the distal end  306  of the member  302  to the catheter guide  316 . Compression screw  320  is provided on the catheter guide  316  to secure a catheter relative to the catheter holder  300 .  
         [0087]      FIG. 16  is a side view of an alternate catheter holder  350  in accordance with the present invention. Catheter locking pin  352  is positioned through the tubular portion  354  of the member  356 . Distal end  358  of the catheter locking pin  352  compressively engages with catheter  360  against edge  362  of the member  356  to secure it in place relative to the catheter holder  350 . Threaded member  364  can be used to advance the catheter locking pin  352  toward the catheter  360 , such as for example to fix the position of the catheter  360  relative to the catheter holder  350 , or to cut the catheter  360  and cured biomaterial contained within using a sharpened distal end  358 .  
         [0088]      FIGS. 17A and 18A  illustrate an alternate catheter holder  400 A that can optionally be used without a secondary holding device. The catheter  404 A is secured to the annulus  86 , and in particular, within the annulotomy  91 .  
         [0089]     Outer sleeve  402 A surrounds the catheter  404 A. Distal end  406 A of the outer sleeve  402 A is attached to the catheter  404 A by a flexible material  408 A. The flexible material  408 A can be rubber, silicone, or any other elastically or plastically expandable material. In one embodiment, the flexible material  408 A forms a continuous structure, such as for example a disc or a toroid. In another embodiment, the flexible material  408 A can be a multi-lobed structure, which can optionally be constructed from metal.  
         [0090]     As best illustrated in  FIG. 18A , the outer tube  402 A is displaced in the direction  410 A relative to the catheter  404 A, causing the flexible material  408 A to deform in an outward direction  412 A. Protrusions  414 A expand into the edges of the annulotomy  91  in the annulus  86 , forming an interference or compression fit. The present embodiment secures the catheter holder  400 A from movement in either direction along the axis  416 A, preferably without a secondary holding device.  
         [0091]     In one embodiment, the external surface of the protrusions  414 A can optionally include a variety of surface features  415 A to releasably engage with the edge of the annulotomy  91 , such as for example ridges, spikes, and the like. The surface features serve to more securely anchor the protrusions  414 A to the annulotomy  91 . A variety of the embodiments disclosed herein can also benefit from the use of such surface features. In one embodiment, the resulting protrusions  414 A operate as a surgical tools such as a stop, discussed in other embodiments herein.  
         [0092]      FIGS. 17B and 18B  illustrate an alternate catheter holder  400 B in which the protrusions  414 B are deployed subcutaneous, outside of the annulus  86 . In this embodiment, the surgical tool  420 B is positioned against the edge of the annulotomy  91  establishes a frame of reference for the procedure, providing greater accuracy. The outer tube  402 B is displaced in the direction  410 B relative to the catheter  404 B as discussed above, causing the flexible material  408 B to deform in an outward direction  412 B. The present embodiment secures the catheter holder  400 B from movement in either direction along the axis  416 B, preferably without a secondary holding device. In one embodiment, the resulting protrusions  414 B operate as a surgical tools making the stop  420 B unnecessary, discussed in other embodiments herein.  
         [0093]      FIGS. 19A and 20A  illustrate an alternate catheter holder  450 A that can optionally be used without a secondary holding device. The catheter  464 A is secured to the annulus  86 , and in particular, within the edges of the annulotomy  91 . Expandable bladder  452 A is fitted on external surface  454 A of tubular member  456 A. Delivery tube  458 A is in fluid communication with the expandable bladder  452 A.  
         [0094]     The expandable bladder  452 A is positioned within the annulotomy  91 . As best illustrated in  FIG. 20A  a fluid is delivered to the expandable bladder  452 A through the delivery tube  458 A, causing it to inflate. The inflated bladder  460 A forms an interference or compression fit within the annulotomy  91 . The inflated bladder  460 A serves to secure the tubular member  456 A along either direction of axis  462 A, using the edge of the annulotomy  91  and the surgical tool  474 A as the frame of reference for the procedure. Delivery catheter  464 A, or a variety of other devices, can be inserted through the tubular member  456 A. In an alternate embodiment, the bladder  452 A can be located directly on the catheter  464 A, obviating the tubular member  456 A. In one embodiment, the inflated bladder  460 A operates as a surgical tool such as a stop, making the surgical tool  474 A unnecessary.  
         [0095]      FIGS. 19B and 20B  illustrate an alternate catheter holder  450 B in accordance with the present invention. The expandable bladder  452 B is positioned outside the annulotomy  91 . As best illustrated in  FIG. 20B  a fluid is delivered to the expandable bladder  452 B through the delivery tube  458 B, causing it to inflate. The inflated bladder  460 B is deployed subcutaneous, outside of the annulus  86 . The inflated bladder  460 B forms an interference or compression fit within the tissue outside of the annulus  86  to secure the tubular member  456 B along either direction of axis  462 B. The inflated bladder  460 B can alternately be located in the annulotomy  91 , outside the annulus  86 , inside the annulus  86 , or a combination thereof. In one embodiment, the inflated bladder  460 B operates as a surgical tools such as a stop.  
         [0096]      FIG. 20C  illustrates an alternate interface of the inflated bladder  460 C with the annulus  86 . The inflated bladder  460 C extends across the depth of the annulotomy  91  so that a portion  466 C is located outside the annulus  86  and a portion  468 C is located inside the annulus  86 . In the embodiment of  FIG. 20C , the inflated bladder  460 C has a generally hourglass shape. The portion  466 C limits movement of the catheter holder  450 C in the direction  470 C and the portion  468 C limits movement of the catheter holder  450 C in the direction  472 C.  
         [0097]      FIG. 21  is a side sectional view of an alternate catheter holder  500  in accordance with the present invention. Catheter  502  is optionally fitted with an expandable bladder  504 . Sheath  506  can optionally be slid over the delivery tube  502  and expandable bladder  504  to control the location and degree of expansion of the bladder  504 . In the illustrated embodiment, the expanded bladder  504  engaged with edges of the annulotomy  512  in the annulus  514 . The embodiment of  FIG. 21  is particularly useful when biomaterials are injected into the annulus  512  without mold  516 , since the bladder  504  not only fixes the catheter holder  500  relative to the annulus  86 , it also seals the annulotomy  91  to allow biomaterial to be injected under pressure without leaking out. As discussed above, the inflated bladder  504  limits movement of the catheter holder  500  along either direction of the axis  510 , making it unnecessary to secure the proximal end of the catheter  502  to the surgical table or other fixed structure.  
         [0098]      FIGS. 22 and 23  illustrate an alternate catheter holder  550  in accordance with the present invention. Expandable strap  552  is positioned around the catheter  554 . Proximal end  553  of the expandable strap  552  is preferably attached to the catheter  554 .  
         [0099]     As best illustrated in  FIG. 23 , when force  556  is applied to distal end  558  of this strap  552 , the portion surrounding the catheter  554  contracts concentrically inward. The mold  562  attached to the distal end of the catheter  554  is then positioned in the cavity  566  formed inside annulus  570 . When the force  556  is released, the strap  552  expands to its substantially original shape to form a friction or interference fit with the annulotomy  568  in the annulus  570 . When the procedure is completed, the surgeon reapplies the force  556  to contract the strap  552 , and the strap  552  is removed from the annulotomy.  
         [0100]      FIG. 24  is a cross-sectional view of an annulus  86  engaged with an alternate catheter holder  600  in accordance with the present invention. Distal end  602  of member  604  includes cut-out  606  that permits catheter  608  to be inserted into the annular cavity  84  formed in the annulus  86 . In the illustrated embodiment, surgical tool  610  operates to support region  612  of the annulus  86  and to retract and protect blood vessels and nerves. In the illustrated embodiment, the surgical tool  610  can also operate as a nerve guard ring.  
         [0101]     In operation, as a fluid, such as a curable biomaterial, is delivered through the catheter  608 , the mold  614  inflates within the cavity  84 . Alternatively, the biomaterial is injected directly into the annulus  86  without use of the mold  614 . In some applications, the inflated mold  614  or the biomaterial located in the annulus  86  exert pressure  616  on the annulus  86 , such as region  612 . Portion  618  of the surgical tool  610  provides a counteracting force  620  that restrains deformation of the annulus  86 . In particular, the portion  618  prevents the annulus  86  from impinging on spinal column  622 . The surgical tool  610  is particularly useful when the portion  612  of the annulus  86  is diseased or otherwise weakened, and hence, prone to distend or deform when subjected to the pressure of the biomaterial.  
         [0102]     Depending upon the size of the portion  618 , the surgical tool  610  can optionally be positioned in the patient before the member  604 .  FIG. 34  illustrates one possible embodiment of an insertion tool  750  in accordance with the present invention. Member  754  forms an articulating connection between distal end  752  and the member  756 . Member  754  articulates through at least one degree of freedom, and preferably two or more degrees of freedom. In the illustrated embodiment, member  754  is a pivot point around which the distal end  752  rotates along arc  758  relative to the member  754 . The distal end  752  mechanically engages with a surgical tool, such as the surgical tools in  FIGS. 26 and 30 .  
         [0103]     In the embodiment of  FIG. 24  the surgical tool  610  is preferably releasably attached to the distal end  602  of the member  604 , such as by a snap-fit arrangement, a mechanical release or a variety of other mechanisms. In particular, the surgeon inserts the surgical tool  610  into the patient against the annulus  86 . The opening  624  (see  FIGS. 25-26 ) on the surgical tool  610  is aligned with the annulotomy  91 . The catheter holder  600  is then inserted into the annulotomy  91  so that the distal end  602  engaged with the opening  624  on the surgical tool  610 . Once the mold  614  or the annulus  86  is filled with curable biomaterial, the sequence is reversed to remove the surgical tool  610  from the patient.  
         [0104]     In an alternate embodiment, second catheter holder  652  is optionally engaged with posterolateral annulotomy  654 , in accordance with the present invention. In the illustrated embodiment, the catheter holder  652  includes a second lumen  656  fluidly coupled to the mold  614  and a visualization device  658 , such as an endoscope.  
         [0105]     The second catheter holder  652  provides a second discrete access port  654  into the annulus  86  that optionally can be used to form the annular cavity  84 , to image any phase of the procedure, to deliver the biomaterial to the mold  614  through the second lumen  656 , to draw a vacuum on the mold  614  before, during and/or after delivery of the biomaterial, and to secure the prosthesis in the intervertebral disc space during and after delivery of the biomaterial. Various multi-lumen molds and mechanisms for securing a prosthesis in the annulus are disclosed in U.S. Provisional application entitled Multi-Lumen Mold for Intervertebral Prosthesis and Method of Using Same, filed on the same date herewith (attorney docket no. 319570), which is hereby incorporated by reference.  
         [0106]     As best illustrated in  FIGS. 25 and 26 , the surgical tool  610  includes an opening  624  sized to engage with distal end  602  of the member  604 . An optional anti-rotation feature  626 , such as a notch, is provided to engage with a corresponding feature  628  on the distal end  602 . The portion  618  includes a width “W”, a length “L” and an optional curvature “C”. The desired width, length and curvature can vary with the patient. In another embodiment, the portion  618  has a curvilinear shape with varying radii of curvature. In another embodiment, the portion  618  has a constant radius of curvature. The present invention includes a kit having a plurality of interchangeable surgical tools  610  having a variety of widths, lengths, and curvatures.  
         [0107]      FIGS. 27 and 28  illustrate front and side views of the member  604  of  FIG. 24  with an alternate surgical tool  650  engaged with distal end  602 . The member  604  is preferably constructed from a radio-translucent plastic, with a plurality of radiopaque markers  630  attached or embedded therein. Alternatively, the member  604  is constructed from a radiopaque material. The radiopaque markers  630  can have a variety of shapes and can be arranged in a variety of configurations, such as for example the straight lines arranged at fixed intervals illustrated in  FIGS. 27 and 28 .  
         [0108]     As best illustrated in  FIGS. 29 and 30 , the surgical tool  650  includes the same opening  624  and anti-rotation feature  626  as the surgical tool  610 . The surgical tools  610  and  650  are preferably interchangeable with the distal end  602  of the member  604 .  
         [0109]      FIGS. 31-33  illustrate an alternate mounting flange  700  in accordance with the present invention. Extension  702  includes a slot  704  sized to receive a catheter  608 . Recess  706  and slot  708  are preferably configured to engage with a mounting arm attached to a fixed location, such as the surgical table. Once such mounting arm is a component of a micro-discectomy system sold by Medtronic under the trade name MetrX®.  
         [0110]      FIG. 35  is a side view of an alternate catheter holder  800  in accordance with the present invention. Member  802  includes a primary lumen  804  and a secondary lumen  806 . In the illustrated embodiment,  804  is a working lumen and  806  is a visualization lumen. The relative sizes of the lumens  804 ,  806  are schematically illustrated and can vary with the application.  
         [0111]     Surgical tool  808  engages with the annulus  86  adjacent to the annulotomy  91 . The location of the surgical tool  808  along the member  802  is optionally adjustable with a snap-fit sliding motion. A second surgical tool, reinforcing member  810  is delivered to the cavity  84  into the annulus  86  preferably through the member  802 . The reinforcing member  810  operates to support region  812  of the annulus  86 . The reinforcing member  810  is optionally a shaped memory metal, such as for example nitinol.  
         [0112]     In operation, as a fluid, such as a curable biomaterial, is delivered through the catheter  804 , the mold  814  inflates within the cavity  84 . In some applications, the inflated mold  814  exerts pressure  816  on the annulus  86 , such as at the region  812 . Alternatively, in an embodiment where the biomaterial is injected directly into the annulus  86  without the use of a mold  814 , the biomaterial exerts pressure  816  on the region  812 .  
         [0113]     The surgical tool  810  provides a counteracting force  820  and/or distributes the force  816  over a larger surface area to temporarily reinforce the region  812  of the annulus  86 . In particular, the surgical tool  810  prevents the annulus  86  from protruding into the spinal cord  822 . The surgical tool  810  is particularly useful when the portion  812  of the annulus  86  is diseased or otherwise weakened, and hence, prone to distend or deform when subjected to the pressure of the inflated mold  814 . Preferably after the biomaterial is at least partially cured, the reinforcing member  810  is removed from the annulus  86  through the member  802 . In an alternate embodiment, the surgical tool  810  can engage with an exterior surface of the annulus  86 , such as illustrated in  FIG. 24 .  
         [0114]     In another embodiment, the surgical tool  810  is released from the member  802  and remains in the annulus  86  after the procedure is completed. The surgical tool  810  is preferably release from the member  802  after the biomaterial is at least partially cured. In one embodiment, the surgical tool  810  is constructed from a bio-resorbable material.  
         [0115]      FIG. 36  is a side sectional view of an alternate catheter holder  850  in accordance with the present invention. The member  852  includes one or more outer engagement wires  854 ,  856  and one or more inner engagement wires  858 ,  860 . Catheter  862  and mold  864  are preferably located in center region  866  of member  852 .  
         [0116]     As illustrated in  FIG. 37 , member  852  is located adjacent to annulus  86 . The inner engagement wires  858 ,  860  are extended from the member  852  so that curved portions  870 ,  872  engage with inner surface  874  of the annulus  86  adjacent to the annulotomy  91 . The outer engagement wires  854 ,  856  are also extended from the member  852  so that curved portions  874 ,  876  engage with outer surface  878  of the annulus  86  adjacent to the annulotomy. The engagement wires  858 ,  860  prevent the catheter holder  850  from moving in a direction  880 , while the engagement wires  854 ,  856  prevent movement in direction  882 . The catheter holder  850  can be used with or without a secondary holding device. The catheter  862  can be positioned in and secured to the member  852  using any of the methods disclosed herein.  
         [0117]     The catheter holder of the present invention can also be used with the method of implanting a prosthetic nucleus disclosed in a commonly assigned U.S. Patent Application entitled Lordosis Creating Nucleus Replacement Method And Apparatus (Attorney Docket No. 318946), filed on the same date herewith, the disclosure of which are incorporated herein by reference.  
         [0118]     Patents and patent applications disclosed herein, including those cited in the Background of the Invention, are hereby incorporated by reference. Other embodiments of the invention are possible. Many of the features of the various embodiments can be combined with features from other embodiments. In particular, any of the present catheter holder can be combined with the surgical tools, multi-lumen molds and/or entry ports discussed herein. It is to be understood that the above description is intended to be illustrative, and not restrictive. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.