Abstract:
A system for correcting pectus excavatum includes a pectus bar having an elongated main body portion with posterior and anterior sides and opposing ends, and a lateral cross section. A pectus bar extraction tool has a handle, the handle having a head at an end of the handle. The head has an elongated slot for receiving the pectus bar. The slot is dimensioned to receive the lateral cross section of pectus bar such that the pectus bar can be positioned in the slot and the handle manipulated to impart a force on the pectus bar. A pectus bar extraction tool and a method for removing a pectus bar are also disclosed.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This Application is a Continuation-in-Part of U.S. Non-Provisional application Ser. No. 12/692,232, filed Jan. 22, 2010, entitled SURGICAL TOOL FOR PECTUS BAR EXTRACTION. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    Pectus excavatum (PE), also called sunken or funnel chest, is a congenital chest wall deformity which is characterized, in most cases, by a deep depression of the sternum. Very often other problems can accompany this condition, like scoliosis and breathing issues. The correction of pectus excavatum (PE) and similar chest deformities has two main goals. Using the minimally-invasive Nuss procedure, one or two metal bars are placed to change the chest geometry which, in most cases, effects a positive result on a patient&#39;s physiology. Secondly, subjective aesthetic improvement may be achieved. 
         [0003]    According to the Nuss procedure, incisions are made under the skin in the lateral chest wall at each lateral side of the patient and a skin tunnel is raised from the incision to the top of the pectus ridge. A tool known as a pectus introducer is inserted through the incision and used to create a tunnel for the pectus bar. The pectus introducer is advanced under the sternum and then through the opposite lateral incision. The pectus bar is shaped to fit the patient. The pectus bar is then inserted through the tunnel, with the convexity facing posteriorly. The pectus bar is then inverted to raise the sternum and anterior chest wall. The pectus bar is secured in place, for which one or more stabilizers can be used, and the incisions are closed. 
         [0004]    The pectus bar remains in the patient for a treatment period lasting about 2 years or until the physician determines that the correction is complete and then is removed. Tissue grows around and in some cases directly adheres to the pectus bar, making removal difficult. Currently, surgical tools for removing the bars have proved inadequate for many surgeons. 
       SUMMARY OF THE INVENTION 
       [0005]    A pectus bar extraction tool for removing a pectus bar having posterior and anterior sides, includes a handle, an engagement member and a lever arm. The engagement member is fixed to and extends from the handle extending from the anterior to the posterior side of the pectus bar to engage the posterior side of the pectus bar. The lever arm is fixed to and extends from the handle opposite to the engagement member to rest upon the pectus bar on the anterior side of the pectus bar and act as a fulcrum. 
         [0006]    The engagement member can provide a protrusion adapted for placement through an aperture in the pectus bar. The protrusion can be a hook. The width of the hook can be less than one-half of the width of the pectus bar. The hook extends distally to the handle. 
         [0007]    The lever arm can comprise lateral side members for engaging lateral side portions of the pectus bar. A web can be provided between the lateral side members, and can be dimensioned so that the pectus bar will fit between the lateral side members and contact the web. The lateral side members can be rails. 
         [0008]    The handle can include an indented portion. The indented portion assists in gripping when the handle is in proximity to a surface, such as an operating room table. 
         [0009]    A system for correcting pectus excavatum can include a pectus bar and a pectus bar extraction tool. The pectus bar has an elongated main body portion with posterior and anterior sides and opposing ends, and structure at the ends for engaging the pectus bar extraction tool. The pectus bar extraction tool can include a handle and an engagement member fixed to the handle for cooperating with the engagement structure on the pectus bar to engage the extraction tool to the pectus bar. The engagement member of the pectus bar extraction tool can extend under the pectus bar to engage the posterior side of the pectus bar. The pectus bar extraction tool can have a lever portion for engaging the pectus bar on the anterior side. 
         [0010]    A method for extracting a pectus bar from a patient includes the step of providing a pectus bar having an elongated main body portion with posterior and anterior sides and opposing ends, and engagement structure at the ends for engaging a pectus bar extraction tool, the pectus bar having been surgically implanted in the patient. A pectus bar extraction tool having a handle and an engagement member fixed to the handle for cooperating with the engagement structure on the pectus bar is also provided. The engagement member on the pectus bar extraction tool is engaged to the engagement structure on an opposing end of the pectus bar. A second pectus bar extraction tool can be engaged to the engagement structure at the other opposing end of the pectus bar. Using the handles, the extraction tools are manipulated to apply a straightening force to the pectus bar so as to at least partially straighten the pectus bar, whereby the pectus bar can be removed from the patient. 
         [0011]    A system for correcting pectus excavatum includes a pectus bar having an elongated main body portion with posterior and anterior sides and opposing ends, and a lateral cross section. A pectus bar extraction tool includes a handle having a head at an end. The head includes an elongated slot for receiving the pectus bar. The slot is dimensioned to receive the lateral cross section of the pectus bar such that the pectus bar can be positioned in the slot and the handle manipulated to impart a force on the pectus bar. 
         [0012]    The handle has a long axis and the elongated slot has a long axis. The long axis of the handle and the long axis of the slot can be substantially perpendicular. 
         [0013]    The height of the slot can be no more than 2 mm greater than the height of the lateral cross section of the pectus bar, and the width of the slot can be no more than 2 mm greater than the width of the lateral cross section of the pectus bar. The height of the slot can be no more than 1 mm greater than the height of the lateral cross section of the pectus bar, and the width of the slot can be no more than 1 mm greater than the width of the lateral cross section of the pectus bar. 
         [0014]    The pectus bar extraction tool can comprise an engagement member and the pectus bar can comprise structure at the opposing ends for engaging the engagement member. The engagement member of the pectus bar extraction tool when engaged to the pectus bar extends from the anterior to the posterior sides of the pectus bar to engage the posterior side of the pectus bar. 
         [0015]    The head of the pectus bar extraction tool can further comprise a lever arm for engaging the pectus bar on the anterior side of the pectus bar. The engagement member and the lever arm can be aligned along an axis and extend oppositely from one another. The axis of the elongated slot can be transverse to the axis of the lever arm and engagement member. The engagement member can be a curved projection for extending from the anterior to the posterior sides of the pectus bar to engage the posterior side of the pectus bar. The projection can be a hook. The width of the hook can be less than one-half of the width of the pectus bar. The lever arm can comprise a step for contacting the pectus bar. The step can be provided at an end of the head and the hook can be provided at an opposite end of the head. 
         [0016]    A pectus bar extraction tool for removing an elongated pectus bar from a patient, the pectus bar having anterior and posterior sides and a lateral cross section, the extraction tool comprising a handle having a head at an end of the handle, the head comprising an elongated slot for receiving the pectus bar, the slot being dimensioned to receive the lateral cross section of the pectus bar such that the pectus bar can be positioned in the slot. 
         [0017]    The handle has a long axis and the elongated slot has a long axis, and the long axis of the handle and the long axis of the slot can be substantially perpendicular. The head of the pectus bar extraction tool can further comprise a lever arm for engaging the pectus bar on the anterior side of the pectus bar. The lever arm can include lateral side members for engaging lateral side portions of the pectus bar. The lateral side members can be rails. 
         [0018]    A method for extracting a pectus bar from a patient can include the step of providing a pectus bar having an elongated main body portion with posterior and anterior sides and opposing ends, and a lateral cross section, where the pectus bar has been surgically implanted in the patient. A pectus bar extraction tool is provided. The pectus bar extraction tool comprises a handle. The handle has a head at an end of the handle. The head comprises an elongated slot for receiving the pectus bar. The slot is dimensioned to receive the lateral cross section of pectus bar such that the pectus bar can be positioned in the slot and the handle manipulated to impart a force on the pectus bar. 
         [0019]    The pectus bar extraction tool is engaged to the pectus bar by positioning the pectus bar extraction tool adjacent an end of the pectus bar and moving the pectus bar extraction tool relative to the end of the pectus bar such that the end enters the slot of the pectus bar extraction tool. The pectus bar extraction tool is moved to a desired position on the pectus bar. The pectus bar extraction tool is then manipulated to apply a force to the pectus bar. 
         [0020]    A second pectus bar extraction tool can be engaged to another opposing end of the pectus bar by positioning the other opposing end through an slot in the head of the second pectus bar extraction tool. The handles can then be used to apply forces from the first and second pectus bar extraction tools to the pectus bar. 
         [0021]    The pectus bar extraction tool can further comprise an engagement member fixed to the head for cooperating with engagement structure on the pectus bar. The engagement member on the head comprises a projection and the engagement structure on the pectus bar comprises an aperture for receiving the projection. The projection on the pectus bar extraction tool is positioned in the aperture of the pectus bar. The handle is manipulated to apply a force from the projection to the pectus bar. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    There is shown in the drawings embodiments which are presently preferred, it being understood, however, that the invention can be embodied in other forms without departing from the spirit or essential attributes thereof. 
           [0023]      FIG. 1  is a side elevation of a pectus bar extraction tool according to the invention. 
           [0024]      FIG. 2  is a perspective view of a distal end of the extraction tool. 
           [0025]      FIG. 3  is a front elevation. 
           [0026]      FIG. 4  is a cross section taken along line  4 - 4  in  FIG. 3 . 
           [0027]      FIG. 5  is a cross section illustrating the extraction tool engaged to a pectus bar. 
           [0028]      FIG. 6  is a cross section through the human anatomy illustrating the use of extraction tools according to the invention to remove a pectus bar according to a method of the invention, in a first mode of operation. 
           [0029]      FIG. 7  is a cross section through the human anatomy illustrating the use of extraction tools to remove a pectus bar according to a method of the invention, in a second mode of operation. 
           [0030]      FIG. 8  is a perspective view of a pectus bar extraction tool according to an alternative embodiment. 
           [0031]      FIG. 9  is a rear elevation of an extraction tool head. 
           [0032]      FIG. 10  is a cross-section taken along A-A in  FIG. 9 . 
           [0033]      FIG. 11  is a side elevation. 
           [0034]      FIG. 12  is a bottom view. 
           [0035]      FIG. 13  is a perspective view, partially broken away, and showing the extraction tool engaged to a pectus bar. 
           [0036]      FIG. 14  is a side elevation. 
           [0037]      FIG. 15  is a cross-section taken along line A-A in  FIG. 14 . 
           [0038]      FIG. 16  is a schematic diagram illustrating a use of the pectus bar extraction tool according to the alternative embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0039]    A pectus bar extraction tool according to the invention is shown in  FIGS. 1-7 . The extraction tool  10  according to the invention includes an elongated handle  12 . An engagement member  16  is fixed to and extends from the handle  12 . The engagement member  16  extends under a pectus bar  20  to engage the posterior side  32  of a pectus bar  20 . A lever arm  24  is fixed to and extends from the handle  12  oppositely from the engagement member  16  for engaging the pectus bar  20  on the anterior side  28  of the pectus bar  20 . 
         [0040]    The engagement member  16  can be in the shape of a protrusion extending distally and outwardly relative to the handle  12  so as to provide a hook or claw shape. The dimensions of the engagement member can vary, and in one aspect the width of the hook is less than one-half the width of the pectus bar  20 . The hook or other engagement member  16  can be provided with a rounded or blunt end so as to avoid damage to tissue during the pectus bar removal process. Other dimensions and configurations of the engagement member  16  are possible. A tongue and groove engagement, a flange and slot, hooks and loops, or various other detachable mechanical engagement structures are possible. The attachment should be secure enough to apply the forces required to straighten the pectus bar  20  and to free the pectus bar from surrounding tissue, and the attachment should be made from the anterior side  28  of the pectus bar  20  to the extent possible so that excessive cutting or tearing of tissue is not required to position the engagement member under or around the pectus bar  20 . 
         [0041]    The lever arm  24  engages an anterior surface  28  of the pectus bar  20  while the engagement member  16  engages a posterior surface  32  ( FIG. 5 ). The handle  12  can then be manipulated to rotate the engagement member  16  in the direction of the arrow, and the lever arm  24  will contact the anterior surface  28  so as to straighten the pectus bar  20  and to pry the pectus bar  20  from tissue to which it may be connected. 
         [0042]    The lever arm  24  can comprise a web  36  and lateral side members such as rails  40 . The web  36  provides a contact surface for the pectus bar  20  that is a distance from the handle  12  and engagement member  16  so as to act as a lever to lend additional force to the engagement member  16  and pry the pectus bar  20  from surrounding tissue. The lateral side members are positioned so as to receive the pectus bar  20  between them, and with the web  36 , to provide for secure engagement of the pectus bar  20  so that the engagement member  16  does not become disengaged from the pectus bar  20  and is stabilized on the bar. 
         [0043]    The handle  12  can be fashioned in different shapes and sizes. In one embodiment, the handle  12  has a curved portion  44  to offset the proximal portion  48  of the handle which is gripped by the user, from the distal portion  52 . This will allow for gripping of the proximal portion  48  of the handle  12  when it is horizontal and adjacent to a surface such as an operating room table. An opening  54  can be provided in the proximal portion  48  to further facilitate gripping. The length of the handle can be adjusted for the preference of the user, the amount of leverage that is necessary, or the particular removal procedure that will be performed. 
         [0044]    The invention can be used with pectus bars having a variety of shapes and sizes. The pectus bar  20  has at least one aperture  56 . The engagement member  16  extends through the aperture  56  so as to engage the posterior surface  32 . The pectus bar  20  is generally elongated and planar, and with differing dimensions according to the size and shape of the patient and the particular characteristics of the patient. The pectus bar  20  is usually made from a material that is pliable, so that the pectus bar  20  can be shaped in the operating room by the surgeon to fit the particular patient. The pectus bar  20  can be made from surgical quality metals or plastics. 
         [0045]    A method for extracting a pectus bar from a patient is shown in  FIGS. 6-7 . The engagement member  16  of the pectus bar extraction tool  10  is positioned through the aperture  56  and thereby engaged to the pectus bar  20 . Preferably two extraction tools  10  are provided, one for each end of the pectus bar  20  at each lateral side  64  of the patient. The second pectus bar extraction tool is engaged to the engagement structure at the other end of the pectus bar  20 . The handles of the pectus bar extraction tools  10  are used to apply a straightening force to the pectus bar so as to at least partially straighten the pectus bar  20 , as depicted by the arrows in  FIG. 6 . A twisting motion can then be applied to the handles to assist in dislodging the pectus bar  20  from surrounding tissue, as depicted by the arrows in  FIG. 7 . The pectus bar  20  can then be removed from the patient from a position posterior to the sternum  60 . 
         [0046]    There is shown in  FIGS. 8-16  an alternative pectus bar extraction tool  70 . The extraction tool  70  has a head  74  communicating with a handle  94  with a long axis  95  ( FIG. 10 ). The handle  94  can have a grip portion  98  to facilitate grasping and manipulation of the tool  70 . A pectus bar engagement slot  90  is provided in the head  74 . The slot  90  can be elongated and can have a long axis  99  extending through the slot  90  (see  FIG. 12 ). The long axis  95  of the handle  94  and the long axis  99  of the elongated slot  90  can be substantially perpendicular. As used herein, substantially perpendicular means 90°, or 90°±20°, ±15°, ±10°, or ±5°. The slot  90  is dimensioned to receive the lateral cross-section of the pectus bar  20  such that the pectus bar  20  can be positioned in the slot  90  and the handle  94  manipulated to impart a force on the pectus bar  20 . The height of the slot  90  is greater than the height of the lateral cross section of the pectus bar, and the width of the slot  90  is greater than the width of the lateral cross section of the pectus bar. 
         [0047]    The slot  90  can be provided according to different constructions of the head  74 . In the embodiment shown, the slot  90  comprises an opening  91  on each lateral side of the head  74 . An open-faced groove  85  formed by top wall  92  and side walls  93  is fashioned in the head  74  between the openings  91  and is dimensioned to receive the pectus bar  20 . The groove  85  adjoins the openings  91 , such that the top wall  92  and side walls  93  of the groove  85  also form the top and side walls of the openings  91 . The opening  91  has a bottom wall  89 . It is alternatively possible to fashion a fully-enclosed slot  90  in the head  74 . Other constructions for the slot  90  are possible. 
         [0048]    The height and width of the slot  90 , and/or the openings  91  forming a part of the slot  90 , are selected relative to the cross-sectional dimensions of the pectus bar  20  such that a significant amount of play between the tool  70  and the pectus bar  20  is not possible. The dimensions of the slot  90  are preferably just wide enough receive the pectus bar  20 . In one aspect, the height and width dimensions of the slot  90  are each no more than 1 mm greater than the height and width dimensions of the pectus bar  20 . This results in a gap (distances a and b in  FIG. 14A ) of no more than 1 mm. In another aspect the height and width of the slot  90  are no more than 0.5 mm to 2 mm greater than the height and width of the pectus bar  20 , or any length there between. In one example, the dimensions of the lateral cross-section of the pectus bar  20  is 2.9 mm in height and a 12.7 mm in width, and the dimensions of the slot  90  are about 3.9 mm in height and 13.7 mm in width. This will provide small gaps a and b between the pectus bar  20  and the walls  92 ,  93  of the slot  90  so that the extraction tool  70  can slip easily over the pectus bar  20 , but without significant play between the pectus bar  20  and the walls  92 ,  93  of the slot  90 . The tool  70  may thereby be used to manipulate the pectus bar  20  without undue wobble or play. The desired difference in dimensions between the slot  90  and the lateral cross sectional dimensions of the pectus bar  20  can vary, for example, for pectus bars having greater dimensions the gap distances a and b can be greater, while for pectus bars having smaller distances the gap distances can be less. The gap distances a and b should be greater than 0 but no more than 1% to 30% of the respective height or width dimension of the pectus bar  20 , or any percentage there between, such as 5%, 10%, 15%, 20%, or 25%. 
         [0049]    The length L of the slot  90  ( FIG. 12 ) is preferably no more than 2 times the length of the head  74  as measured along the axis  97 . The length L will be limited by the dimensions of the head  74 . The length L should not be too small or a bending force will be applied to the pectus bar  20  when the extraction tool is used to apply a force to the pectus bar  20 . The length L should not be too long, as a slot  90  that is too long will be difficult to position over a curved section of the pectus bar  20 . 
         [0050]    As can be seen in  FIGS. 13-15 , the head  74  can be positioned over the pectus bar  20  by positioning the tool  70  such that the end  100  of the pectus bar  20  enters the slot  90 . The tool  70  is then moved laterally inward from the end  100  in the direction indicated by the arrow  102  such that tool  70  engages the pectus bar  20  ( FIG. 13 ). 
         [0051]    The operation of the alternative extraction tool  70  is shown in  FIG. 16 . The extraction tool  70  is positioned laterally inward from the end  100  of the pectus bar  20 . The extraction tool  70  is then used to lift and pry the pectus bar  20 , as indicated by the arrows  103 - 104 . The pectus bar  20  will be securely engaged within the slot  90  such that slippage and wobble are minimized. A second extraction tool  70  can be positioned over the opposite end  100  of the pectus bar  20 . The two tools  70  can then be manipulated in the fashion shown in  FIG. 16  to manipulate the pectus bar  20 . 
         [0052]    The alternative extraction tool  70  can have additional structure to assist in removal of the pectus bar  20 . In one embodiment, the head  74  has an engagement member  78  as previously described fixed to and extending from the head  74 . The head  74  can also have a lever arm  86  and lateral side rails  82 . A protruding flange or step  83  can be provided to engage the pectus bar  20  in a downward and countervailing direction to the upward force imparted by the engagement member  78 . The engagement member  78  and lever arm  86  can be aligned along an axis  97  ( FIG. 12 ) and extend oppositely to one another relative to the axis  95  of the handle  94 . The axis  99  of the slot  90  can be transverse to, and can be substantially perpendicular to, the axis  97 . As used herein, substantially perpendicular means 90°, or 90°±20°, ±15°, ±10°, or ±5°. As previously described the pectus bar  20  can fit between the rails  82  to assist in aligning the engagement tool  70  and to prevent twisting. The engagement member  78  extends through an aperture in the pectus bar  20  and to an opposite side of the pectus bar  20  to engage the pectus bar  20 . The handle  94  can thereby be manipulated to force the lever arm  86  against the pectus bar  20 , while prying upward against the anterior side of the pectus bar  20  using the engagement member  78 , as shown in  FIG. 5 . 
         [0053]    The engagement member  78  is first used to lift the ends  100  of the pectus bar  20  from the tissue of the patient. The engagement member  78  is engaged to the pectus bar  20  by placing the engagement member  78  through the aperture  56 , whereby the pectus bar  20  can be pried and lifted from the tissue in which the pectus bar  20  has been embedded during the remodeling process. The engagement member  78  can be a protrusion or a hook. The diameter and material of the hook  78  can be adapted for the stresses that will be applied to the hook  78 . The diameter of the hook should be as large as will permit insertion through the aperture  56  of the pectus bar  20  without collision. A high strength metal such as 17-4 H900 stainless steel can be used to provide additional strength to the hook  78 . Lifting the pectus bar  20  out of the tissue enables the end  100  of the pectus bar  20  to be positioned in the slot  90 . The tool  74  can then be moved to any desired position on the pectus bar  20  to impart lifting and prying forces wherever desired. 
         [0054]    The length of the head  74  along the axis  97  ( FIG. 12 ) can vary. Increasing this length will decrease the forces acting on the hook  78 . The longer the head  74 , the longer the incision must be on the side of the patient. This incision length is typically about 30 mm to 40 mm. In one aspect this length can be from 20 mm to 30 mm, and in another aspect can be 22 mm to 27 mm. 
         [0055]    The step  83  can be provided at an end of the head  74  that is opposite to the end having the hook  78  so as to insure that the distance from the point of contact between the pectus bar  20  and the step  83  of the lever arm  86  is as far as possible from the point of contact of the hook  78  with the pectus bar  20 . This will act to decrease the forces acting on the hook  78 . 
         [0056]    This invention can be embodied in other forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be had to the following claims rather than the foregoing specification as indicating the scope of the invention.