Abstract:
A retractor system and method for locating and placing a polyaxial screw while substantially simultaneously retracting tissue is shown and described. The retractor has a channel that facilitates introducing a rod into the polyaxial screw. Various embodiments are shown, including one which utilized a reducer for moving the rod in the retractor.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application is a continuation of U.S. application Ser. No. 13/765,905 filed Feb. 13, 2013, which is a continuation of U.S. application Ser. No. 13/355,654 filed Jan. 23, 2012, now issued as U.S. Pat. No. 8,398,644, which is a continuation of U.S. application Ser. No. 12/477,489 filed Jun. 3, 2009, now issued as U.S. Pat. No. 8,142,436, which claims priority to provisional U.S. Application Ser. No. 61/059,417 filed Jun. 6, 2008, to which Applicant claims the benefit of the earlier filing date. These applications are incorporated herein by reference and made a part hereof 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    A retraction tube for use with a capless spinal screw which allows for the rotation of the screw locking body within, and relative to, the retraction tube. In another embodiment, a retraction tube for use with a capless spinal screw which attaches rigidly to said screw and is dimensioned to permit rotation of said tubular attachment relative to a fixation element. 
         [0004]    2. Description of the Related Art 
         [0005]    The placement of spinal screws is a common surgical procedure. There is a need to reduce the size of the incision necessary for the placement of such screws. Small tubular tissue retractors have been used to minimize incision size. More recently, tubular attachments have been developed which attach to the screws themselves, performing tissue retraction during the act of screw placement. Typically, the screws are engaged into bone, while the retraction tubes protrude upward through the skin. At this point a fixation element, typically a metallic rod, is placed either through or adjacent to the retraction tubes in order to engage the screws. Typically, a locking cap is then placed through the tube to lock the fixation element to the screws. As demonstrated in the prior art, such tubes attach rigidly to the screw body and do not permit the rotation of the screw body needed to perform locking of the fixation element to the screws. 
         [0006]    Recently, there has been the development of capless spinal screws which utilize rotation of the screw body to achieve locking of the fixation element to the capless screws. Current retraction tubes are not capable of being used with capless screws. Since capless screws require rotation of the screw body in order to perform rod locking, an improved retraction tube is needed which allows for rotational screw locking to take place within the tube. 
       SUMMARY OF THE INVENTION 
       [0007]    One object of the invention is to provide a retractor for retracting tissue and that is adapted to rotate or permit rotation of a capped or capless polyaxial screw. 
         [0008]    Another object of the invention is to provide a reducer for moving the rod in the retractor. 
         [0009]    In one aspect, an embodiment comprises a retractor/reducer assembly for use in combination with a reducer comprising a retractor comprising an elongated member for detachably mounting onto a polyaxial screw receiver having a rod-locking channel for receiving and locking onto a rod, said elongated member comprising a rod-receiving channel for receiving said rod and for guiding said rod into said rod-locking channel, said elongated member having a first end for receiving and detachably mounting onto said polyaxial screw receiver, and a reducer for rotatably mounting on said elongated member, at least a portion of said reducer extending over and at least partially surrounding said polyaxial screw receiver and having a generally helical channel for receiving said rod and for urging said rod to move in said rod-receiving channel of said retractor and into said rod-locking channel in response to rotation of said reducer while said screw is stationary. 
         [0010]    In another aspect, another embodiment comprises a reducer comprising an elongated tubular member having a generally helical reducer channel, said elongated tubular member being adapted and configured to mount onto a polyaxial screw receiver having a rod-locking channel, said generally helical reducer channel receiving a rod and causing said rod to move in said rod-locking channel said polyaxial screw receiver in response to a rotation of said elongated tubular member, at least a portion of said reducer extending over and at least partially surrounding said polyaxial screw receiver and having a generally helical channel for receiving said rod and for urging said rod to move into said rod-locking channel in response to rotation of said reducer while said screw is stationary. 
         [0011]    In still another aspect, another embodiment comprises a method for guiding or placing a rod in a screw in a patient during a surgical procedure comprising the steps of screwing the screw into bone, placing the rod in a generally helical channel of a reducer, and driving the rod into a channel of the screw in response to rotation of said reducer. 
         [0012]    The above mentioned aspects and the embodiments shown and described herein could be used alone or together and/or in combination with one or more of the features covered by one or more of the claims set forth herein, including but not limited to one or more of the following features or steps: 
         [0013]    The retractor wherein the elongated member comprises at least one inner wall for mounting onto an outer surface of the polyaxial screw receiver, the at least one inner wall being adapted to permit the polyaxial screw receiver to be rotated by rotating the elongated member until the rod becomes locked in the polyaxial screw receiver. 
         [0014]    The retractor wherein the elongated member comprises at least one inner wall for mounting onto an outer surface of the polyaxial screw receiver, the at least one inner wall being adapted to permit the polyaxial screw receiver to be rotated to lock the rod in the polyaxial screw receiver while the elongated member is held stationary. 
         [0015]    The retractor wherein the elongated member is adapted to permit the elongated member to be removed from the polyaxial screw receiver by moving the elongated member axially away from the polyaxial screw receiver after the polyaxial screw receiver has been rotated. 
         [0016]    The retractor wherein at least a portion of the rod-receiving channel comprises a shape or configuration that is generally the same as a shape or configuration of the rod-locking channel so that when the elongated member is mounted onto the polyaxial screw receiver, the rod-receiving channel and the rod-locking channel can become generally aligned to permit the rod to be received so that the elongated member can be rotated in a first direction to cause the polyaxial screw receiver to lock the rod in the polyaxial screw receiver and then rotated in a second direction generally opposite the first direction without unlocking the rod from the polyaxial screw receiver. 
         [0017]    The retractor wherein the elongated member comprises an end having a first recessed wall and a second recessed wall that generally opposes the first recessed wall, the first and second recessed walls defining a first shape that generally complements a second shape of an outer surface of the polyaxial screw receiver. 
         [0018]    The retractor wherein the first and second shapes are arcuate and dimensioned to enable the end of the elongated member to be fit onto the polyaxial screw receiver with a press or interference fit. 
         [0019]    The retractor wherein a frictional engagement between the first and second recessed walls and the outer surface is less than a coupling strength between the polyaxial screw receiver and the rod, thereby permitting the elongated member to rotate after the polyaxial screw receiver is locked onto the rod and without unlocking the polyaxial screw receiver from the rod. 
         [0020]    The retractor wherein the elongated member adapted to permit the elongated member to be removed from the polyaxial screw receiver by moving the elongated member axially away from the polyaxial screw receiver after the rod is locked in the polyaxial screw receiver. 
         [0021]    The retractor wherein the rod-receiving channel traverses a majority of a longitudinal length of the elongated member. 
         [0022]    The retractor wherein the rod-locking channel is not entirely straight and the rod-receiving channel is generally straight. 
         [0023]    The retractor wherein neither of the rod-locking channel nor the rod-receiving channel is straight. 
         [0024]    The retractor wherein the elongated member comprises a first end having a recessed area adapted to capture the polyaxial screw receiver with a frictional engagement that permits the polyaxial screw receiver to be rotated by the elongated member and permit the elongated member to rotate or move independent of any movement of the polyaxial screw receiver. 
         [0025]    The retractor wherein the first end comprises a coupler or aligner for facilitating coupling or aligning, respectively, the elongated member to the polyaxial screw receiver. 
         [0026]    The retractor wherein the coupler comprises at least one projection on at least one of the elongated member or the polyaxial screw receiver and a generally complementary receiving area on the other of the polyaxial screw receiver or the at least one of the elongated member, respectively, for receiving the at least one projection to facilitate coupling the elongated member to the polyaxial screw receiver. 
         [0027]    The retractor wherein the coupler or aligner causes the rod-locking channel and the rod-receiving channel to become generally aligned when the elongated member is mounted onto the polyaxial screw receiver. 
         [0028]    The retractor wherein the elongated member is generally tubular and comprises a first arcuate wall and a second arcuate wall generally opposing the first arcuate wall, the first and second arcuate walls having ends that are spaced to define the rod-receiving channel, the elongated member is sized to permit a tool to be used to screw the screw after it is received in the polyaxial screw receiver and the elongated member is mounted onto the polyaxial screw receiver. 
         [0029]    The retractor wherein the elongated member comprises a first end for mounting onto the polyaxial screw receiver and a second end opposite the first end, the second end having a stabilizer for holding the elongated member. 
         [0030]    The retractor wherein the retractor further comprises a reducer for rotatably mounting on the elongated member, the reducer urging the rod to move in the rod-receiving channel and into the rod-locking channel. 
         [0031]    The retractor wherein the reducer comprises a reducer channel. 
         [0032]    The retractor wherein the reducer channel is non-linear. 
         [0033]    The retractor wherein the reducer channel is helical, the reducer further comprising a tubular wall having a first cut out area and a second cut out area, the first and second cut out areas being spaced approximately 180 degrees and defining the reducer channel. 
         [0034]    The retractor wherein the reducer comprises a grip for manually rotating the reducer about the elongated member. 
         [0035]    The retractor wherein the reducer comprises an internal reducer receiving area adapted and dimensioned to receive the elongated member so that the reducer can be rotatably mounted thereon. 
         [0036]    The retractor wherein the elongated member is tubular and the reducer is adapted and dimensioned to be rotatably mounted inside the elongated member. 
         [0037]    The retractor wherein the rod-receiving channel of the elongated member and the reducer channel are adapted to receive the rod and cooperate to guide and urge rod into the rod-locking channel upon rotation of the reducer. 
         [0038]    The retractor wherein an end of the reducer comprises at least one stop to prevent over rotation of the reducer once the rod is captured in a seat of the rod-locking channel or the polyaxial screw receiver. 
         [0039]    The reducer wherein the reducer channel is non-linear. 
         [0040]    The reducer wherein the reducer channel is helical, the reducer further comprising a tubular wall having a first cut out area and a second cut out area, the first and second cut out areas being spaced approximately 180 degrees and defining the helical reducer channel. 
         [0041]    The reducer wherein the reducer comprises a grip for manually rotating the reducer about the elongated member. 
         [0042]    The reducer wherein the reducer comprises an internal reducer receiving area adapted and dimensioned to receive the elongated member of the retractor so that the reducer can be rotatably mounted on the elongated member. 
         [0043]    The reducer wherein the elongated member of the retractor and the reducer are both tubular, the reducer being adapted and dimensioned to be rotatably mounted inside the elongated member. 
         [0044]    The reducer wherein the reducer comprises at least one stop associated with the reducer channel to prevent over rotation of the reducer once the rod is captured in a seat of the rod-locking channel or the polyaxial screw receiver. 
         [0045]    The retractor wherein the retractor body further comprises at least one inner wall for mounting onto an outer surface of the polyaxial screw receiver, the at least one inner wall being adapted to cause the polyaxial screw receiver to rotate by rotating the retractor body until the rod becomes locked in the polyaxial screw receiver. 
         [0046]    The retractor wherein the retractor body comprises at least one inner wall for mounting onto an outer surface of the polyaxial screw receiver, the at least one inner wall being adapted to permit the polyaxial screw receiver to be rotated to lock the rod in the polyaxial screw receiver while the retractor body is held stationary. 
         [0047]    The retractor wherein the retractor body is adapted to permit the retractor body to be removed from the polyaxial screw receiver by moving the retractor body axially away from the polyaxial screw receiver after the polyaxial screw receiver has been rotated. 
         [0048]    The retractor wherein at least a portion of the rod-receiving channel comprises a shape or configuration that is generally the same as a shape or configuration of the rod-locking channel so that when the retractor body is mounted onto the polyaxial screw receiver, the rod-receiving channel and the rod-locking channel become generally aligned to enable the retractor body to be rotated in a first direction to cause the polyaxial screw receiver to rotate and lock the rod in the polyaxial screw receiver and then rotated in a second direction generally opposite the first direction without rotating the polyaxial screw receiver in the second direction. 
         [0049]    The retractor wherein the retractor body comprises an end having a first recessed wall and a second recessed wall that generally opposes the first recessed wall, the first and second recessed walls cooperating to define a female receiving area that generally complements and mates with an outer surface of the polyaxial screw receiver. 
         [0050]    The retractor wherein the end of the retractor body fits onto the polyaxial screw receiver with a press or interference fit. 
         [0051]    The retractor wherein a frictional engagement between the first and second recessed walls and the outer surface is less than a coupling strength between the polyaxial screw receiver and the rod, thereby permitting the retractor body to rotate after the polyaxial screw receiver is locked onto the rod without unlocking the polyaxial screw receiver from the rod. 
         [0052]    The retractor wherein the retractor body is adapted to permit the retractor body to be removed from the polyaxial screw receiver by moving the retractor body axially away from the polyaxial screw receiver after the rod is locked in the polyaxial screw receiver. 
         [0053]    The retractor wherein the rod-receiving channel traverses a majority of a longitudinal length of the retractor body. 
         [0054]    The retractor wherein the rod-locking channel is not entirely straight and the rod-receiving channel is generally straight. 
         [0055]    The retractor wherein neither the rod-locking channel nor the rod-receiving channel are straight. 
         [0056]    The retractor wherein the retractor body comprises a first end having a recessed area adapted to capture the polyaxial screw receiver with a frictional engagement that permits the polyaxial screw receiver to be rotated by the retractor body and permit the retractor body to rotate or move independent of any movement of the polyaxial screw receiver. 
         [0057]    The retractor wherein the first end comprises a coupler or aligner for facilitating coupling or aligning the retractor body to the polyaxial screw receiver. 
         [0058]    The retractor wherein the coupler comprises at least one projection on at least one of the retractor body or the polyaxial screw receiver and a generally complementary receiving area on the other of the polyaxial screw receiver or the at least one of the retractor body, respectively, for receiving the at least one projection to facilitate coupling the retractor body to the polyaxial screw receiver. 
         [0059]    The retractor wherein the coupler causes the rod-locking channel and the rod-receiving channel to become generally aligned when the retractor body is mounted onto the polyaxial screw receiver. 
         [0060]    The retractor wherein the retractor body is generally tubular and comprises a first arcuate wall and a second arcuate wall generally opposing the first arcuate wall, the first and second arcuate walls having ends that are spaced to define the rod-receiving channel, the retractor body is sized to permit a tool to be used to screw the screw after it is received in the polyaxial screw receiver and the retractor body is mounted onto the polyaxial screw receiver. 
         [0061]    The retractor wherein the retractor body comprises a first end for mounting onto the polyaxial screw receiver and a second end opposite the first end, the second end having a stabilizer for holding the retractor body. 
         [0062]    The retractor wherein the retractor further comprises a reducer for rotatably mounting on the retractor body, the reducer urging the rod to move in the rod-receiving channel and into the rod-locking channel. 
         [0063]    The retractor wherein the reducer comprises a reducer channel. 
         [0064]    The retractor wherein the reducer channel is non-linear. 
         [0065]    The retractor wherein the reducer channel is helical, the reducer further comprising a tubular wall having a first cut out area and a second cut out area, the first and second cut out areas being spaced approximately 180 degrees and defining the helical reducer channel. 
         [0066]    The retractor wherein the reducer comprises a grip for manually rotating the reducer about the retractor body. 
         [0067]    The retractor wherein the reducer comprises an internal reducer receiving area adapted and dimensioned to receive the retractor body so that the reducer can be rotatably mounted thereon. 
         [0068]    The retractor wherein the retractor body is tubular and the reducer is adapted and dimensioned to be rotatably mounted inside the retractor body. 
         [0069]    The retractor wherein the rod-receiving channel of the retractor body and the reducer channel are adapted to receive the rod and cooperate to guide and urge the rod into the rod-locking channel upon rotation of the reducer. 
         [0070]    The retractor wherein the reducer comprises at least one stop associated with the reducer channel to prevent over rotation of the reducer once the rod is captured in a seat of the rod-locking channel or the polyaxial screw receiver. 
         [0071]    These and other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims. 
     
    
     
       DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS 
         [0072]      FIG. 1  is perspective view of a retraction device or apparatus according to one embodiment of the invention; 
           [0073]      FIG. 2  is a sectional view of a retraction device or apparatus, taken along line  2 - 2  of  FIG. 1 ; 
           [0074]      FIG. 3  is a sectional view taken along line  3 - 3  of  FIG. 1 ; 
           [0075]      FIG. 4  is a view of the retraction device or apparatus; 
           [0076]      FIG. 5  is a sectional view of the retraction device or apparatus, taken along line  5 - 5  of  FIG. 4 ; 
           [0077]      FIG. 6  is a fragmentary view, partly in cross-section, of a retraction device or apparatus with a capless screw engaged; 
           [0078]      FIG. 7  is a fragmentary view of a retraction device or apparatus with a capless screw engaged; 
           [0079]      FIG. 8  is a fragmentary view, similar to  FIG. 7 , showing another position thereof; 
           [0080]      FIG. 9  is an exploded view of another embodiment of a retraction device or apparatus; 
           [0081]      FIG. 10  is a view similar to  FIG. 9 , showing the retractor mounted on a capless polyaxial screw; 
           [0082]      FIG. 11  is a fragmentary view of the retraction device or apparatus and capless screw rigidly fixed and showing a rod in a first position; 
           [0083]      FIG. 12  is a view similar to  FIG. 11  with the rod moved to another position; 
           [0084]      FIG. 13  is an enlarged fragmentary view showing the retraction device or apparatus and screw with a locking interface so that rotation of the tube in turn causes rotation of the receiver into a locking position; 
           [0085]      FIG. 14  is a perspective view of another embodiment showing a retractor and a reducer; 
           [0086]      FIGS. 15-17  are various views illustrating the reducer urging or forcing the rod into a rod-locking channel of the receiver; 
           [0087]      FIG. 18  is a view illustrating the reducer being removed from the retractor; 
           [0088]      FIG. 19  is a view illustrating the retractor rotating the receiver after the rod is received in the rod-locking channel and the reducer has been removed from the retractor; 
           [0089]      FIG. 20  is a sectional view taken along the lines  20 - 20  in  FIG. 17 ; and 
           [0090]      FIG. 21  is an exploded view showing reducer that fits inside the retractor. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0091]    Referring now to  FIGS. 1-21 , a retraction tube system is shown comprising a retractor, retraction device or apparatus  10 . A first illustrative embodiment is shown relative to  FIGS. 1-8  wherein a retractor, retraction device or apparatus  10  is shown. As illustrated in  FIG. 1 , the retractor, retraction device or apparatus  10  comprises a generally tubular or cylindrical retractor body  12  having an inner wall  12   a  that defines an aperture  14 . The retractor, retraction device or apparatus  10  in the illustration being shown is tubular and cylindrical in cross section. A pair of cut-outs  16  and  18  is provided in the retractor body  12 . The cut-outs  16  and  18  define a first elongated portion, leg or wall  20  and a second elongated portion, leg or wall  22  as shown. The cut-outs  16  and  18  also cooperate to define a rod-receiving channel  26  for receiving a rod  28 . 
         [0092]    Note that an end  20   a  ( FIG. 1 ) of the first elongated portion  20  has an inner wall  20   c  ( FIG. 2 ) having a recessed wall  20   a   1 , and an end  22   a  of the second elongated portion  22  has an inner wall  22   c  ( FIG. 2 ) having a recessed wall  22   a   1 . The recessed walls  20   a   1  and  22   a   2  cooperate to define an area  24  for receiving a polyaxial screw  29  ( FIGS. 8 and 9 ). In the illustration being described, the polyaxial screw  29  comprises a capless receiver or polyaxial screw receiver  30  and a screw  29   a  ( FIG. 8 ) that is received in the capless receiver  30 . The polyaxial screw  29  may be of the type as shown and illustrated in U.S. Pub. Patent Application Nos. 2007/0043357A1, now issued as U.S. Pat. No. 7,717,943; 2007/0123867A1; 20060155278A1, now issued as U.S. Pat. No. 7,662,172; 2007/0123862A1, now issued as U.S. Pat. No. 7,604,655; 2008/0097457A1, now issued as U.S. Pat. No. 8,012,185; 2008/0071277A1, now issued as U.S. Pat. No. 8,092,504; 2008/0249576A1, now issued as U.S. Pat. No. 8,097,025; 2007/0093827A1, now issued as U.S. Pat. No. 7,686,835, all of which are assigned to the same assignee as the present application and which are incorporated herein by reference and made a part hereof. The polyaxial screw  29  may comprise at least one inner member (not shown), such as a compression member (not shown), of the type disclosed in one or more of the cited applications. 
         [0093]    Note that the receiver  30  comprises a generally L-shaped rod-locking channel or slot  30   a  ( FIGS. 6-8 ) conventionally known. The rod-locking channel  30   a  has an opening  30   a   1 , a seat  30   a   2 , and a seat  30   a   3  as shown in  FIG. 6 . The receiver  30  comprises an outer surface  30   b  that has a diameter that is dimensioned or adapted to permit the receiver  30  to be received in the receiving area  24  and rotate within and relative to the retraction device or apparatus  10  after the receiver  30  is received between the recessed walls  20   a   1  and  22   a   1  in the receiving area  24 . Note that the outer wall  30   b  of receiver  30  may comprise a lip or flange  30   b   1  having a retaining function described later herein. 
         [0094]    As best illustrated in  FIGS. 1 and 7 , notice that the retractor body  12  has the pair of generally opposed walls, legs, portions  20  and  22  ( FIG. 1 ). The walls, legs or portions  20  and  22  are arcuate or curved in cross-section. The recessed walls  20   a   1  and  22   a   1  and associated cut-outs  16  and  18  cooperate to define the rod-receiving channel  26  that receives the rod  28  ( FIG. 7 ). The retractor body  12  comprises at least one or a plurality of lips or flanges  20   b  and  22   b  integrally formed in walls  20  and  22  and that engage and cooperate with the lip or flange  30   b   1  on receiver  30  to retain the receiver  30  in the area  24  and on the retractor body  12 . In the illustration being described the first and second elongated portions or legs  20  and  22  are resilient and elastic so that they can deflect to receive the receiver  30  when it is received in the area  24  between the inner walls  20   a   1  and  22   a   1 . In the illustration being described, a friction or interference fit is provided so that the receiver  30  can be slid onto and rotated within the retractor body  12  in the embodiment shown in  FIGS. 1-8 . 
         [0095]    During a surgical procedure, a surgeon makes an incision and the retraction device or apparatus  10 , which has an assembly of the receiver  30  and screw  29   a  after the screw  29   a  is received in the receiver  30  and the receiver  30  is received in the receiving area  24 , is inserted through the incision and the screw  29   a  is screwed into bone with a screw driver (not shown) inserted through the aperture  14  of retractor body  12 . The retractor, retraction device or apparatus  10  causes the tissue to be retracted during the act of the placement of the polyaxial screw  29 . 
         [0096]    It should be understood that after the screw  29   a  is placed and screwed into the bone of the patient, a tool  32  ( FIG. 7 ) may be inserted into the aperture  14  of the retractor body  12  in the illustration of  FIGS. 1-8 . The tool  32  comprises a working end  32   a  that is received in the channel or slot  30   a  of the receiver  30 . After the rod  28  has been positioned in the desired position subsequent to screw  29   a  placement, the tool  32  can be received in the channel or slot  30   a  and the receiver  30  rotated (clockwise in the illustration being described) in order to lock the receiver  30  onto the rod  28 . It should be understood that in the illustration being described the retraction device or apparatus  10  does not rotate during the rotation of the receiver  30 . 
         [0097]    Moreover, as with the second embodiment described later, it should be understood that the retraction device or apparatus  10  may be mounted onto the receiver  30  and then the screw  29   a  placed or screwed into the bone, thereby providing a single unit for the surgeon to substantially simultaneously place the screw  29   a  and retract the tissue. It should be understood that the screw  29   a  and receiver  30  could alternatively be placed or screwed into the bone and then the retraction device or apparatus  10  placed over and mounted on the receiver  30  if desired. 
         [0098]    Note that the retractor body  12  comprises the rod-receiving channel  26  that is generally elongated and traverses a majority or substantially all of the length of the retractor body  12 . The rod-receiving channel  26  is aligned with the opening  30   a   1  of the rod-locking channel  30   a  so that when a rod  28  is placed in the rod-receiving channel  26  of the retractor body  12  it can be easily aligned with and guided into the opening  30   a   1  of the rod-locking channel  30   a  and downward toward the seat  30   a   2 , as illustrated in  FIGS. 6 and 7 . 
         [0099]    After the rod  28  is positioned in the seat  30   a   2 , the tool  32  ( FIG. 7 ) can be used to rotate the receiver  30  to lock the rod  28  in the receiver  30 . After the receiver  30  locks the rod  28  therein, the retractor body  12  can be removed and dismounted from the receiver  30  by pulling it away from the receiver  30 . In this illustration, the rod-receiving channel  26  in the retractor body  12  is substantially linear or straight, while the rod-locking channel  30   a  in the receiver  30  is not straight and is generally L-shaped as shown.  FIGS. 7 and 8  illustrate the receiver  30  after it has been rotated from the unlocked position ( FIG. 7 ) to the locked position ( FIG. 8 ) using the tool  32 . 
         [0100]    In the illustrations described herein, the retractor body  12  is tubular and cylindrical, but it should be understood that it could take different forms, such as a solid form, without departing from the scope of the invention. For example, the retractor body  12  could be non-cylindrical (e.g., hexagonal, octagonal, square or like). 
         [0101]    In the illustration being described, an indicia  39   a  ( FIG. 8 ) may be provided on the retractor body  12  and a second indicia  39   b  provided on the outer surface  30   b  to facilitate aligning the rod-receiving channel  26  with the opening  30   a   1  of the rod-locking channel  30   a . Alternatively, and as described later herein relative to other embodiments, a coupler  31 ′ ( FIG. 9 ) may be provided that facilitates coupling and aligning the retractor body  12 ′ to the receiver  30 ′. 
         [0102]    Note that a dimension or width (as viewed in  FIG. 4 ) of the rod-receiving channel  26  is substantially the same as a dimension or width of the inlet  30   a   1  of the rod-locking channel  30   a . Advantageously, the channel  26 ′ and retractor body  12 ′ provide an alignment guide for receiving the rod  28 ′ and directing the rod  28 ′ through the slot or channel  26 ′ and into the rod-locking channel  30   a ′ of the receiver  30 . 
         [0103]      FIGS. 9-13  illustrate another embodiment of the invention. Like parts are identified with the same part numbers in this embodiment, except that an apostrophe (“′”) has been added to the part numbers in this embodiment. 
         [0104]    In this embodiment, the retraction device or apparatus  10 ′ rotates with the receiver  30 ′ during locking of the rod  28 ′ in the receiver  30 ′. In this illustration, note that the retractor body  12 ′ of retraction device or apparatus  10 ′ comprises a generally L-shaped rod-receiving channel  34 ′ ( FIG. 10 ) that has a shape and dimension that generally complements a shape and dimension of the rod-locking channel  30   a ′ of the receiver  30 ′. As best illustrated in  FIGS. 11 and 12 , the rod  28 ′ is inserted into an elongated portion  34   a ′ of the rod-receiving channel  34 ′ and then moved downward (as viewed) into opening  30   a   1 ′. Notice that after the rod  28 ′ is placed in the seat  30   a   2 ′ of rod-locking channel  30   a ′ of the receiver  30 ′ both the retraction device or apparatus  10 ′ and the receiver  30 ′, are rotated together to the locked position, as illustrated in  FIGS. 11 and 12 . 
         [0105]    After the receiver  30 ′ is locked onto the rod  28 , the retraction device or apparatus  10 ′ may be rotated relative to the receiver  30 ′ in a counterclockwise direction in the illustration being described and then removed or detached from the receiver  30 ′. In this regard, the frictional fit engagement and clamping force between the recessed wall  20   a   1 ′ and  22   a   1 ′ and the outer surface  30   b ′ of the receiver  30 ′ is less than the coupling strength between the receiver  30 ′ and the rod  28 ′, thereby permitting the retraction device or apparatus  10 ′ to rotate after the receiver  30 ′ is locked onto the rod  28 ′ and without rotating and unlocking the receiver  30 ′ from the rod  28 ′. 
         [0106]    As illustrated in  FIGS. 9-11 , the receiver  30 ′ may comprise a coupler  31 ′, such as a notch, tooth or other male projections  20   a   2 ′ and  22   a   2 ′ that are received in notched-out areas or slots  30   d   1 ′ and  30   d   2 ′, respectfully. This feature facilitates locking the retraction device or apparatus  10 ′ to the receiver  30 ′. This feature also reduces or facilitates reducing undesired rotation of the retraction device or apparatus  10 ′ relative to the receiver  30 ′ during rotation of the retraction device or apparatus  10 ′ and receiver  30 ′ and locking of the receiver  30 ′ onto the rod  28 ′. The coupler  31 ′ also facilitates automatic or quick alignment of channel  34 ′ with the rod-locking channel  30   a ′ when the retractor body  12 ′ is mounted on the receiver  30 ′. 
         [0107]    Referring now to  FIGS. 14-21 , another embodiment of the invention is shown. In this embodiment, like parts are identified with the same part numbers, except that a double apostrophe (“″”) mark has been added to the part numbers in  FIGS. 14-21 . In this embodiment, an implant system is shown comprising a polyaxial screw assembly similar to the assembly shown in  FIGS. 6-13 . This embodiment further comprises a reducer  60 ″, which will be described later herein. The retractor body  12 ″ is detachably mounted onto the polyaxial screw  29 ″ and receiver or polyaxial screw receiver  30 ″ in the manner describer earlier. 
         [0108]    As with the embodiments illustrated in  FIGS. 6-13 , the retractor body  12 ″ detachably mounts onto the outer wall  30   b  of the polyaxial screw receiver  30 ″. The retractor body  12 ″ further comprises a rod-receiving channel  34 ″. The rod-receiving channel  34 ″ becomes generally aligned with an opening  30   a   1 ″ and ultimately to the seat  30   a   2 ″. As with the prior embodiments, the rod-receiving channel  34 ″ and the retractor body  12 ″ is adapted to facilitate urging and guiding the rod  28 ″ into the channel opening  30   a   1 ″ and ultimately to the seat  30   a   2 ″ in the manner described herein. 
         [0109]    The retractor body  12 ″ comprises the first elongated portion, leg or wall  20 ″ and the second elongated portion, leg or wall  22 ″ as shown. An end  20   a ″ of the first elongated portion  20 ″ has the inner or recessed wall  20   a   1 ″, and end  22   a ″ of the second elongated portion  22 ″ comprises the inner or recessed wall  22   a   1 ″. The recessed walls  20   a   1 ″ and  22   a   1 ″ cooperate to define the area  24 ″ for receiving the polyaxial screw receiver  30 ″. 
         [0110]    As with prior embodiments, the first and second recessed walls  20   a   1 ″ and  22   a   1 ″ of the first and second elongated portions  20 ″ and  22 ″ are dimensioned and adapted to be mounted onto the outer surface  30   b ″ of the polyaxial screw receiver  30 ″. A friction, press or interference fit is provided so that rotating the retractor body  12 ″ will cause the polyaxial screw receiver  30 ″ to rotate as in the embodiment illustrated in  FIGS. 9-13 . This rotation is performed after the rod  28 ″ has been received in rod-receiving channel  34 ″, guided into and received in the opening  30   a   1 ″ and seat  30   a   2 ″ of the rod-locking channel  30   a ″ in order to cause the rod  28 ″ to be received in the locking seat  30   a   3 ″ of the polyaxial screw receiver  30 ″. As mentioned, the first and second elongated portions or legs  20 ″ and  22 ″ are elastic and resilient and permit the ends  20   a ″ and  22   a ″ to separate to receive the polyaxial screw receiver  30 ″ until it is captured in the receiving area  24 ″. As with the prior embodiment, notice that the polyaxial screw receiver  30 ″ may comprise the edge or lip  30   b   1 ″. The retractor body  12 ″ comprises the internal lip or flanges  20   b ″ and  22   b ″ that cooperate with the lip  30   b   1 ″ to retain the retractor body  12 ″ on the polyaxial screw receiver  30 ″. 
         [0111]    The at least one inner wall, such as recessed wall  20   a   1 ″ and recessed wall  22   a   1 ″, is adapted to frictionally engage the outer surface  30   b ″ so that by rotating the retractor body  12 ″, the receiver  30 ″ will also rotate until the rod  28 ″ becomes locked in the rod-locking channel  30   a ″ of polyaxial screw receiver  30 ″. In another illustrative embodiment, the at least one inner wall, such as inner wall  20   a   1 ″ and inner wall  22   a   1 ″, are mounted on the polyaxial screw receiver  30 ″ and are adapted to permit the polyaxial screw receiver  30 ″ to be rotated to lock the rod  28 ″ in the polyaxial screw receiver  30 ″ while the retractor body  12 ″ is held stationary as in the embodiment of  FIGS. 1-8 . In that application, the retractor body  12 ″ is held stationary while a tool, such as the tool  32 ″ in  FIG. 7 , is used to rotate the retractor body  12 ″ to the locked position whereupon the rod  28 ″ becomes locked in the polyaxial screw receiver  30 ″. 
         [0112]    As with the embodiment illustrated in  FIGS. 9-13 , the rod-receiving channel  34 ″ comprises a shape, configuration and/or dimension that is generally the same as the shape, configuration or dimension of the rod-locking channel  30   a ″ so that when the retractor body  12 ″ is mounted on the polyaxial screw receiver  30 ″, the rod-receiving channel  34 ″ and rod-locking channel  30   a ″ become generally aligned. It should be understood that, as with the prior embodiments, the receiving area  24 ″ generally defines a female receiving area that generally complements the shape of the outer surface of the polyaxial screw receiver  30 ″. This alignment enables the retractor body  12 ″ to be rotated in a first direction, such as in a clockwise direction, to cause the polyaxial screw receiver  30 ″ to rotate and lock the rod  28 ″ in the polyaxial screw receiver  30 ″ after the rod  28 ″ has been moved through the rod-receiving channel  34 ″ and into the rod-locking channel  30   a ″. Thereafter, the retractor body  12 ″ may be rotated in a second direction, which is generally opposite the first direction, after the polyaxial screw receiver  30 ″ is locked onto the rod  28 ″ and without rotating the polyaxial screw receiver  30 ″ in the second direction as mentioned earlier. In this regard, after the rod  28 ″ has become locked in the polyaxial screw receiver  30 ″, the retractor body  12 ″ can be rotated so as to align the rod-receiving channel  34 ″ with the rod  28 ″ so that the retractor body  12 ″ can be moved axially (in the direction of arrow A in  FIG. 18 ) away from the polyaxial screw receiver  30 ″ and dismounted therefrom. 
         [0113]    The retractor body  12 ″ is fit or mounted onto the polyaxial screw receiver  30 ″ with a friction, press or interference fit. As mentioned earlier, the frictional engagement and gripping strength between the first and second inner walls  20   a   1 ″ and  22   a   1 ″ and the outer surface  30   b ″ of the polyaxial screw receiver  30 ″ is less than a frictional engagement and coupling strength between the polyaxial screw receiver  30 ″ and the rod  28 ″. This permits the retractor body  12 ″ to rotate (counterclockwise in the illustration) about the outer wall or surface  30   b ″ after the polyaxial screw receiver  30 ″ is locked onto the rod  28 ″ and without unlocking or rotating the polyaxial screw receiver  30 ″ to the unlock position. 
         [0114]    As illustrated in  FIG. 14 , the rod-receiving channel  34 ″ is generally L-shaped like the embodiment of  FIGS. 11-13 . A portion  34   a ″ ( FIG. 14 ) traverses a substantial or majority of a length of the retractor body  12 ″. It should be understood, however, that the retractor body  12 ″ of the type illustrated in  FIGS. 1-20  could also be used with this embodiment and comprise a channel, like the channel  26 ″ that is substantially straight or linear, that traverses a majority of a length of the retractor body  12 ″. Thus, the rod-receiving channel  34 ″ could be entirely straight or linear even though the rod-locking channel  30   a ″ is not entirely straight. Alternatively, both the rod-locking channel  30   a ″ and the rod-receiving channel  34 ″ could be either linear or non-linear as illustrated in the figures. 
         [0115]    As with the embodiment shown in  FIGS. 11-13 , the retraction device or apparatus  10 ″ may comprise the coupler  31 ″ for facilitating coupling and securing the retractor body  12 ″ onto the receiver  30 ″. In the illustration described, the coupler  31 ″ may comprise the at least one or a plurality of projection  20   a   2 ″ and  22   a   2 ″ in the walls  20 ″ and  22 ″ of the retractor body  12 ″. As described earlier herein, the projections  20   a   2 ″ and  22   a   2 ″ mate with and are received in the notched-out areas  30   d   1 ″ and  30   d   2 ″ in receiver  30 ″. The notched-out areas  30   d   1 ″ and  30   d   2 ″ each have a shape that generally complements the shape of the projections  20   a   2 ″ and  22   a   2 ″. 
         [0116]    As with the embodiment illustrated in  FIG. 10 , for example, the coupler  31 ″ facilitates securing the retractor body  12 ″ to the receiver  30 ″ and causing the rod-locking channel  30   a ″ and rod-receiving channel  34 ″ to become generally aligned. If a coupler  31 ″ is not provided, the indicia or marking  39   a ,  39   b  ( FIG. 8 ) or other means for aligning the rod-receiving channel  34 ″ with the opening  30   a   1 ″ of the rod-locking channel  30   a ″ may be provided. 
         [0117]    As with the prior embodiments, the retractor body  12 ″ is generally tubular and comprises the first wall  20 ″ and the second wall  22 ″ that are defined by the cut-out cut-outs  16 ″ and  18 . The cut-outs  16 ″ and  18 ″ cooperate to define the rod-receiving channel  34 ″ as with the prior illustrative embodiment. 
         [0118]    As with prior embodiments, the retractor body  12 ″ is sized and adapted to permit a tool, such as the tool  32 ″ ( FIG. 7 ), to be placed in the aperture  14 ″ in order to either rotatably drive the receiver  30 ″ or to engage the head (not shown) of the screw  29   a ″ in order to screw the screw  29   a ″ into bone during the surgical procedure. 
         [0119]    One feature of the embodiment shown in  FIGS. 14-21  is the use of a reducer  60 ″ for urging or driving the rod  28 ″ in the rod-receiving channel  34 ″ until it is received in the opening  30   a   1 ″ and seats  30   a   2 ″,  30   a   3 ″ of the rod-locking channel  30   a ″. The reducer  50 ″ comprises a non-linear reducer channel  66 ″ which in the embodiment illustrated in  FIGS. 14-21  is helical. Note in the illustration being described that reducer  60 ″ comprises a tubular wall  61 ″ having a first cut-out  62 ″ and a second cut-out  64 ″ which cooperate to define the reducer channel  66 ″. The rod  28 ″ may be placed through the cut outs  62 ″ and  64 ″ as illustrated in  FIG. 14  and into the reducer channel  66 ″. In the illustration being described, the first and second cut-outs  62 ″ and  64 ″ define wall portions  61   a ″ and  61   b ″ that are helical. The cut outs  62 ″ and  64 ″ and wall portions  61   a ″ and  61   b ″ and are spaced approximately 180° apart to define the helical reducer channel  66 ″. An end  61   c  of the wall  61 ″ comprises a generally circular knob or grip  68 ″ for facilitating gripping the reducer  60 ″. The grip  68 ″ is integrally formed with the tubular wall  61 ″ and capable of rotating the wall  61 ″ upon rotation of the grip  68 ″. The grip  68 ″ also comprises an annular flange  72 ″ that engages and cooperates with a seat  74 ″ in the retractor body  12 ″ so that the reducer  60 ″ may be rotatably mounted onto the retractor body  12 ″. As shown in  FIG. 21 , another embodiment is provided where the tubular wall  61 ″ is dimensioned and adapted to be received in the aperture  14 ″ inside the retractor body  12 ″ as shown. 
         [0120]    As best illustrated in  FIG. 14 , the reducer  60 ″ comprises an area  80 ″ that is dimensioned and adapted to receive and permit rotation of the retractor body  12 ″ inside the reducer  60 . The rod  28 ″ is placed and traversed through the reducer channel  66 ″ and through the rod-receiving channel  34 ″ as shown. The reducer knob, grip or handle  68 ″ is rotated which causes the rod  28 ″ to traverse the length of both the reducer channel  66 ″ and the rod-receiving channel  34 ″ in the retractor body  12 ″, as illustrated in  FIGS. 15-17 . 
         [0121]    The ends of the tubular wall portions  61   a ″ and  61   b ″ each comprise a stop  82 ″ ( FIG. 17 ) that engages and captures the rod  28 ″ when the rod  28 ″ has reached the end of its travel in the reducer channel  66 ″ and is received in the seat  30   a   2 ″ of the rod-locking channel  30   a ″, as illustrated in  FIGS. 17 and 18 . In the illustration, the stop  82 ″ comprises a curved seat  82   a ″ formed or provided at the ends of the wall portions  61   a ″ and  61   b ″. The curved seat  82   a ″ captures and engages the rod  28 ″ as shown in  FIG. 17 . 
         [0122]    After the rod  28 ″ is received in the seat  30   a   2 ″ of the rod-locking channel  30   a ″ of the receiver  30 ″, the reducer  60 ″ may be removed from the retractor body  12 ″ by moving the reducer  60 ″ axially in the direction of arrow B in  FIG. 18 . After the reducer  60 ″ has been removed from the retractor body  12 ″, the receiver  30 ″ may be rotated (in a clockwise direction in the illustration being described) to lock the rod  28 ″ in the receiver  30 ″ in the manner described earlier relative to  FIGS. 9-13 . Alternatively, the retractor body  12 ″ may be rotated by using the tool  32 ″ in the manner illustrated in  FIG. 7  relative to the prior embodiment. 
         [0123]    In order to stabilize or retain the retractor body  12 ″ in a stationary position during rotation of the reducer  60 ″, a stabilizer  40 ″ ( FIGS. 15 and 16 ) or means for stabilizing the retractor body  12 ″ may be provided. In the illustration being described, the stabilizer  40 ″ may take the form of a plurality of apertures  40   a ″ and  40   b ″ in the retractor body  12 ″ wall. During use, a tool (not shown), such as a screwdriver or other elongated shafted tool or dow, may be placed through the apertures  40   a ″ and  40   b ″ and used to hold the retractor body  12 ″ stationary during rotation of the knob  68 ″ of reducer  60 ″. The tool (not shown) may also be used to rotate the retractor body  12 ″ in order to rotate the receiver  30 ″ to an unlocked or locked position and to pull or detach the retractor body  12 ″ from the receiver  30 ″. 
         [0124]    It should be appreciated that a length of the reducer  58 ″ is selected so that when the rod  28 ″ has reached the stops  82 ″ at the ends of the wall portions  61   a ″ and  60   b ″, respectively, the rod  28 ″ is seated at the seat  30   a   2 ″. This facilitates properly situating and seating the rod  28 ″ in the rod-locking channel  30   a ″ before the receiver  30 ″ is rotated from the open position shown in  FIG. 18  to the locked position illustrated in  FIG. 19 . 
         [0125]    In the illustration being described, the retraction device or apparatus  10  is made of stainless steel, but it should be understood that it could be made of any suitable material that is capable of performing the functions described herein. Thus, for example, the retraction device or apparatus  10  could be made of a polymer material, plastic, composite material, metallic material, such as titanium, or other suitable material. 
         [0126]    Advantageously, the retractor and reducer systems and methods described herein provide means, system and apparatus for guiding or placing a polyaxial screw in a patient and/or situating a rod in the polyaxial screw, while substantially simultaneously retracting tissue during a surgical procedure. 
         [0127]    While the form of apparatus herein and methods described constitutes a preferred embodiment of this invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention.