Abstract:
A surgical retractor and method for retracting tissue in a patient is anatomically designed for particular muscles and includes a light source the light beam of which is positionable relative to the surgical retractor. The surgical retractor has a pair of retraction blades carried on separate retraction portions held open by ratchet assemblies. Blades are manually retracted and held open by automatically engaging ratchet fingers and are designed to match muscle curvature, minimizing various risks and incision size. The first retraction portion carries the first blade and includes tines each with ratchet grooves, while the second retraction portion carries the second blade on a carriage that is movably carried on the tines. Resilient spring actuated fingers associated with the carriage has ratchet grooves that co-act with the ratchet grooves of the tines to provide the ratchet assemblies between the retraction portions that regulates movement of the carriage and the second blade relative to the first blade.

Description:
FIELD OF THE INVENTION 
       [0001]    The present disclosure relates to surgical retractors and devices for stabilizing tissue during a surgical procedure and, particularly, to surgical retractors for use in lower extremity, upper extremity, abdominal, rectal and other areas of the body during a surgical procedure. 
       BACKGROUND 
       [0002]    Many surgical procedures necessitate the use of one or more surgical devices to retract tissue at the surgical site. Such surgical devices are generally known as surgical retractors. A wide variety of surgical retractors have been patented, some for general use and some for specific use. Many of these surgical retractors however, fail to provide any advantages such as, but not limited to, a less complicated and safer surgical procedure that can reduce the risk of nerve damage, anatomical deformity, and cross-contamination, reduce tension on the retracted site, and provide limited incision length. 
         [0003]    Also, many surgical retractors do not take into account the anatomy of the surgical site and thus are not ergonomically designed. If the surgical retractor is not designed and/or made for a specific procedure and/or tissue (e.g. tissue, muscle, muscles, or muscle groups), the risk of damage as noted above is greater. In cases wherein no specific surgical retractor is available, surgical retractors or other surgical instruments not designed for the specific procedure may be used on tissue for which it is not specifically intended. For instance, when performing a muscular lengthening of the gastrocnemius and/or soleus muscles, a vaginal, anal or rectal speculum or standard metal retractor, which is not anatomically designed for the procedure, may be used. 
         [0004]    Moreover, it is vitally important to have adequate lighting for the surgical procedure. However, the availability or amount of light at the surgical site is typically lacking. In view of this, surgical instruments including retractors have been devised that include one or more light sources. Because heat is typically not desired during surgery, the surgical instruments and/or retractors use LEDs as the light source. However, the light sources are fixed with respect to the surgical instrument/retractor. This restricts the ability to provide light to a targeted area during surgery, such as at or in the incision or incision area. Therefore, it is easy to see that current surgical instruments/retractors restrict the visibility due to inadequate lighting within the working space. 
         [0005]    The present invention sufficiently addresses the above concerns. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention is an anatomically correct/designed (i.e. fit-for-purpose) surgical retractor with a positionable light source and method for retracting tissue in a body, such as, but not limited to, the lower extremity, upper extremity, abdominal, rectal and other areas of the body during a surgical procedure. 
         [0007]    The surgical retractor is anatomically designed for particular tissues e.g. a muscle or muscles) of the body and includes a light source the light beam of which can be positioned to shine on a particular area of or about the surgical retractor and/or tissue in order to provide surgical exposure and illumination. The surgical retractor has a pair of retraction blades carried on separate retraction portions that are held open by ratchet assemblies. The blades in an open position create a cutting channel that is wide enough to allow use of standard scalpel blades. 
         [0008]    Each blade may be fashioned as a loop having arms that extend from the retraction portion and which provide an open interior. The loops may be curved from their origin to their tip or otherwise provide a cured surface. This curvature may mimic the curvature of a specific muscle, muscles and/or tissue(s) intended to be retracted especially, but not necessarily, during or for a particular surgical procedure. 
         [0009]    The light source can be an assembly that may be integral to the retractor or as/part of an assembly that is supported on the surgical retractor. An LED or other suitable light source is used along with one or more batteries. In one form, the LED can be rotated to shine or position the light beam toward and/or on the one blade or the other blade. In another form, the LED slides along a section of the surgical retractor to position the light beam accordingly. Other manners of positioning the light beam of the light source may be used and are contemplated. 
         [0010]    In one form, the surgical retractor is characterized by a first retraction portion or arm having a first blade, and a second retraction portion or arm having a second blade, the second retraction portion movably carried on the first retraction portion. Particularly, the first retraction portion includes guide bars each with ratchet grooves of a ratchet assembly, while the second retraction portion includes a carriage movably carried on the guide bars, the second blade extending from the carriage. Resilient spring actuated fingers are associated with the carriage. The resilient spring actuated fingers have ratchet grooves that cooperate and/or co-act with the ratchet grooves of the guide bars to provide ratchet assemblies, ratchets, or ratcheting mechanisms between the first and second retraction portions that allows and prevents movement of the carriage and thus the second blade relative to the first blade. 
         [0011]    In one embodiment, the surgical retractor is designed to be used for the gastrocnemius muscle and the soleus muscle in an intra-muscular approach such as a Baumann procedure (isolated recession of the gastrocnemius muscle and/or the soleus muscle or plantaris tendon or other procedure. It may also be used in a more traditional Strayer procedure below the myotendenous junction from a medial approach. In this approach, the blades of the retraction portions are inserted between the gastrocnemius muscle and the soleus muscle. The LED light source and battery system provides a light source whose light beam is positionable relative to the retractor to provide light on or towards one blade (e.g. adjacent the gastrocnemius muscle), the other blade (e.g. adjacent the soleus muscle), tissue, or other area. 
         [0012]    The present surgical retractor is ergonomically designed to make it easy to maneuver and use. 
         [0013]    The surgical retractor is preferably, but not necessarily, for single use only. However, the surgical retractor may be made for multiple use. The surgical retractor may be, and preferably is, pre-sterilized and packed in a sterile packaging reducing set-up time, cleaning costs, and risk of infections. It may be used in both adult and pediatric patients. 
         [0014]    Although the present surgical retractor is particularly designed for use in the lower extremities, the present surgical retractor may also be used in any areas of the body such as the upper extremity, abdominal and rectal where curved blades and a lighted design may be beneficial. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    The above mentioned and other features of this invention, and the manner of attaining them, will become apparent and the invention itself will be better understood by reference to the following description of the invention taken in conjunction with the accompanying drawings, wherein: 
           [0016]      FIG. 1  is an isometric view of a surgical retractor fashioned in accordance with the present principles; 
           [0017]      FIG. 2  is another isometric view of the surgical retractor of  FIG. 1  shown in conjunction with a soleus muscle; 
           [0018]      FIG. 3  is another isometric view of the surgical retractor of  FIG. 1  shown in conjunction with a gastrocnemius muscle; 
           [0019]      FIG. 4  is a side view of the surgical retractor of  FIG. 1  shown in conjunction with both a soleus muscle and a gastrocnemius muscle; 
           [0020]      FIG. 5  is a view of the surgical retractor of  FIG. 4  taken along line  5 - 5  thereof showing a light beam pattern from the light of the surgical retractor relative to retraction arms of the surgical retractor and to exemplary muscles being held by the retraction arms; 
           [0021]      FIG. 6  is a sectional view of the surgical retractor of  FIG. 4  taken along line  6 - 6  thereof showing the light beam pattern from the surgical retractor light and the light portion of the surgical retractor in sectional; 
           [0022]      FIG. 7  is a sectional view of the surgical retractor of  FIG. 4  taken along line  7 - 7  thereof; 
           [0023]      FIG. 8  is a side view of the surgical retractor of  FIG. 1 ; 
           [0024]      FIG. 9  is a sectional view of the surgical retractor of  FIG. 8  taken along line  9 - 9  thereof; 
           [0025]      FIG. 10  is a top view of the surgical retractor of  FIG. 1  relative to a soleus muscle and a gastrocnemius muscle, the surgical retractor in an un-retracted position; and 
           [0026]      FIG. 11  is a top view of the surgical retractor as shown in  FIG. 10  with the surgical retractor in a retracted position. 
       
    
    
       [0027]    Although the drawings represent a form of various features and components according to the present invention, the drawings are not necessarily to scale and certain features may be enhanced in order to better illustrate and explain the present invention. The exemplification set out herein is not to be construed as limiting the scope of the invention in any manner. 
       DETAILED DESCRIPTION 
       [0028]    Those of skill in the art will understand that various details of the invention may be changed without departing from the spirit and scope of the invention. Furthermore, the foregoing description is for illustration only, and not for the purpose of limitation. 
         [0029]    Referring to the Figures, there is shown a surgical retractor  10  for retracting tissue such as muscles during a surgical procedure. The surgical retractor  10  is preferably, but not necessarily, designed for one time use and thus in this form is disposable. In a multiple use form, the surgical retractor  10  may be made from a suitable metal, metal alloy, or other material that allows the surgical retractor  10  to be used multiple times and/or be cleaned and/or sterilized as necessary. The surgical retractor  10 , with the exception of various components associated with light assembly  16  of the surgical retractor  10 , is thus also preferably, but not necessarily, made from one or more appropriate plastics such as are known in the art. However, other suitable materials such as metal may be used. As pointed out above in the Summary of the Invention, the surgical retractor  10  may be used in lower extremity, upper extremity, abdominal, rectal and other areas of the body during a surgical procedure, particularly, but not necessarily, for retraction of muscles during a surgical procedure. 
         [0030]    With respect to the Figures, the surgical retractor  10  is shown in several of the figures with respect to the gastrocnemius muscle G and the soleus muscle S of the body, it being appreciated that such is only illustrative, and not restrictive, of use of the present surgical retractor  10  for any particular tissue, muscle, muscles, muscle groups. One surgical procedure using the present surgical retractor  10  regarding the gastrocnemius muscle G and the soleus muscle S is a Baumann procedure where the surgical retractor is inserted between the gastrocnemius muscle G and the soleus muscle S. In particular, a Baumann procedure consists of intramuscular lengthening (recession) of the gastrocnemius muscle in the deep interval between the soleus and gastrocnemius muscles. The goal of the procedure is to increase ankle dorsiflexion when ankle movement is restricted by a contracted gastrocnemius muscle. Unlike a Vulpius procedure, which only lengthens the superficial gastrocnemius aponeurosis, the Baumann procedure can do an isolated lengthening of the deep gastrocnemius aponeurosis, but which may also lengthen the superficial soleus aponeurosis. Another procedure is the Strayer procedure which is a posteromedial surgical treatment option for clinically relevant gastrocnemius equinus contracture. Identifying and protecting the sural nerve is an important component of the procedure. 
         [0031]    The present surgical retractor  10  may further be used to lengthen the plantaris tendon to treat ankle equinus or muscular contracture, or as a supplementary treatment of plantar fasciitis, hallux valgus, symptomatic adult acquired flatfoot, metatarsalgia, and/or diabetic foot ulcers, it being appreciated that the aforementioned surgical procedures are only illustrative, and not restrictive, of use of the present surgical retractor  10  for any particular surgical procedure or tissue. 
         [0032]    In general, the surgical retractor  10  has a first retraction arm  12 , a second retraction arm  14  (the nomenclature first and second being arbitrary), and the light assembly  16 , the light assembly  16  carried on the first retraction arm  12 , while the second retraction arm  14  is supported on and movable with respect to the first retraction arm  12 . It should be appreciated that other configurations are contemplated. 
         [0033]    The first retraction arm  12  is characterized by an elongated U-shaped body  18  defining an arced or curved end segment  19 , a first tine  20  extending from a first end of the arced end segment  19 , and a second tine  21  extending from a second end of the arced end segment  19 . A tab or flange  26  extends from a side of the arced end segment  19  in order to provide a place for a user to hold and/or push against the frame  12 , particularly, but not necessarily, during positioning of the surgical retractor  10 . As such, an inner surface  27  of the tab  26  is preferably, but not necessarily, ribbed or otherwise textured. Of course, other manners of providing a finger or hand grip may be used and are contemplated. 
         [0034]    The first retraction arm  12  has a first blade  30  that extends outwardly from a side of the first and second tines  20 ,  21 . The first blade  30  is defined by a body  34  that generally forms a loop that extends from a side of the first tine  20  to a same side of the second tine  21 , and defining an elongated “U” shape with an open interior. Particularly, the body  34  has an upper leg  31  that extends from the side of the first tine  20  to an arched end  33 , and a lower leg  32  that extends from the side of the second tine  21  to the arched end  33 . The body  34  defines a blade that is generally transverse to the first and second tines  20 ,  21  but which preferably, but not necessarily, includes a curvature or bow (see additionally  FIGS. 10-11 ) in order to be anatomically correct with respect to the muscle (tissue) that the blade  30  will contact. As such, and in keeping with the present surgical retractor  10  embodied as a gastrocnemius muscle G/soleus muscle S retractor, the blade  30  is curved in like manner as the gastrocnemius muscle G. The blade  30  is made with other curvature(s) or no curvature depending on the muscle(s) or muscle group(s) being retracted. In this manner, the present surgical retractor  10  may be anatomically designed such that the surgical retractor  10  is fit for a particular purpose and/or surgical procedure. 
         [0035]    A depression or notch  28  is provided in the upper surface of the first tine  20  proximate the arced end segment  19 . The depression  28  preferably, but not necessarily, includes serrations or the like to provide a gripping area. Likewise, a depression or notch  29  is provided in the lower surface of the second tine  21  proximate the arced end segment  19 . The depression  29  preferably, but not necessarily, includes serrations or the like to provide a gripping area. The serrated depressions  28  and  29  allow a user to easily grasp or hold the first retraction arm  12  during use. 
         [0036]    As best seen in  FIG. 9 , an end  22  of the first tine  20  includes teeth, serrations or the like  24  on a lower surface thereof, while an end  23  of the second tine  21  includes teeth, serrations or the like  25  on an upper surface thereof, each forming a part of a ratchet or ratcheting mechanism that provides controlled movement and positional holding of the second retraction arm  14  relative to the first retraction arm  12 . The interaction of the second retraction arm  14  relative to the first retraction arm  12  is discussed below. 
         [0037]    The second retraction arm  14  is characterized by a carriage  46  defined by a generally U-shaped body  51  having an upper limb  47  and a lower limb  48 . A depression or notch  49  is provided in the upper surface of the upper limb  47 , the depression  49  preferably, but not necessarily, including serrations or the like to provide a gripping area. Likewise, a depression or notch  50  is provided in the lower surface of the lower limb  48 , the depression  50  preferably, but not necessarily, including serrations or the like to provide a gripping area. The serrated depressions  49  and  50  allow a user to easily grasp or hold the carriage  46  during use. 
         [0038]    The carriage  46  is movably supported on and by the first and second tines  20 ,  21  of the first retraction arm  12 . Particularly, the upper limb  47  of the carriage body  51  has a bore  66  (see, e.g.,  FIGS. 7 and 9 ) that is shaped complementary to the shape of the first tine  20  such that the first tine  20  extends through the bore  66 . The lower limb  48  of the carriage body  51  has a bore  67  (see, e.g.,  FIGS. 7 and 9 ) that is shaped complementary to the shape of the second tine  21  such that the second tine  21  extends through the bore  67 . The carriage  46  thus slides or moves along the first and second tines  20 ,  21 . Such movement is controlled by upper and lower ratchet/ratcheting mechanisms between the first retraction arm  12  and the second retraction arm  14 . As indicated above, the first tine  20  has a first ratchet portion  24  of the upper ratchet/ratcheting mechanism that include serrations along the lower surface of the end  22  of the first tine  20 , while the second tine  21  has a first ratchet portion  25  of the lower ratchet/ratcheting mechanism that include serrations along the upper surface of the end  23  of the second tine  21 . 
         [0039]    A second ratchet portion of the upper ratchet/ratcheting mechanism includes an upper, resilient finger  52  that extends from the end of the body  51  of the carriage  46  with an actuator  54  situated on the end of the resilient finger  52 , the actuator  54  at least partially surrounding the end  22  of the first tine  20 . The actuator  54  has a serrated notch  56  that provides an area to be grasped by a user&#39;s finger. As best seen in  FIG. 9 , the finger  52  is resilient through a reduced thickness portion  76  of the finger  52  allowing for flexibility and spring action of the finger  52  and thus the actuator  54  relative to the first tine  20 . The actuator  54  has serrations  80  that face and mesh with the serrations  24  of the first tine  20 . The finger  52  and the actuator  54  are normally biased in a latched position as shown in  FIG. 9 . Depressing the actuator  54  disengages the actuator serrations  80  from the serrations  24  of the first tine  20  to allow movement of the actuator  54  and thus the upper limb  47  of the carriage body  51 . 
         [0040]    A second ratchet portion of the lower ratchet/ratcheting mechanism includes a lower, resilient finger  53  that extends from the end of the body  51  of the carriage  46  with an actuator  55  situated on the end of the resilient finger  53 , the actuator  55  at least partially surrounding the end  23  of the second tine  21 . The actuator  55  has a serrated notch  57  that provides an area to be grasped by a user&#39;s finger. As best seen in  FIG. 9 , the finger  53  is resilient through a reduced thickness portion  77  of the finger  53  allowing for flexibility and spring action of the finger  53  and thus the actuator  55  relative to the second tine  21 . The actuator  55  has serrations  81  that face and mesh with the serrations  25  of the second tine  21 . The finger  53  and the actuator  55  are normally biased in a latched position as shown in  FIG. 9 . Depressing the actuator  55  disengages the actuator serrations  81  from the serrations  25  of the second tine  21  to allow movement of the actuator  55  and thus the lower limb  48  of the carriage body  51 . 
         [0041]    As best seen in  FIG. 3 , the second retraction arm  14  has a second blade  60  that extends outwardly from a side of the carriage  46 . The second blade  60  is defined by a body  64  that generally forms a loop that extends from a side of the upper limb  47  of the carriage body  51  to a same side of the lower limb  48  of the carriage body  51 , and defining an elongated “U” shape with an open interior. Particularly, the body  64  has an upper leg  61  that extends from the side of the upper limb  47  of the carriage body  51  to an arched end  63 , and a lower leg  62  that extends from the side of the lower limb  48  of the carriage body  51  to the arched end  63 . The body  64  defines a blade that is generally transverse to the carriage body  51  and the first and second tines  20 ,  21  but which preferably, but not necessarily, includes a curvature or bow (see additionally  FIGS. 10-11 ) in order to be anatomically correct with respect to the muscle (tissue) that the blade  60  will contact. As such, and in keeping with the present surgical retractor  10  embodied as a gastrocnemius muscle G/soleus muscle S retractor, the blade  60  is curved in like manner as the soleus muscle S. The blade  60  is made with other curvature(s) or no curvature depending on the muscle(s) or muscle group(s) being retracted. In this manner, the present surgical retractor  10  may be anatomically designed such that the surgical retractor  10  is fit for a particular purpose and/or surgical procedure. 
         [0042]    The carriage  46  and thus the blade  60  (the second retraction arm  14 ) is movable (adjustable) along the first and second tines  20 ,  21  of the first retraction arm  12 . The carriage  46  moves freely in the retracting/opening direction (i.e. away from the second blade  30 ) by free ratcheting of the upper and lower ratchet mechanisms through spring action of actuators  54 ,  55 . Movement in the un-retracting/closing direction (i.e. towards the second blade  30 ) however, requires manual actuation by depressing both actuators  54  and  55  to overcome the spring bias of the upper and lower ratchet mechanisms thereby releasing the ratchets and allow sliding movement of the carriage  46 . Such movement is indicated by the two oppositely pointing arrows in  FIGS. 2 and 5 . 
         [0043]    In  FIG. 10 , the surgical retractor  10  is in a fully un-retracted position as represented by the arrow extending from the left side of the carriage  46  towards the end  22  of the first tine  20  indicating that the carriage  46  and thus the blade  60  is movable away from the blade  30  to provide tissue retraction. In this position, the blade  60  is closest to the blade  30  and, in particular, the arched end  63  of the blade body  64  of the blade  60  abuts the arched end  33  of the blade body  34  of the blade  30 . In  FIG. 11 , the surgical retractor  10  is in a retracted position as represented by the arrow extending from the right side of the carriage  46  towards the arced end segment  19  of the body  18  of the first retraction arm  12  indicating that the carriage  46  and thus the blade  60  is movable towards the blade  30  for un-retraction. In this position, the blade  60  is a distance from the blade  30 . 
         [0044]    The light assembly  16  is carried on the first retraction arm  12 . With reference to  FIG. 6  the light assembly  16  is shown as having a generally cylindrical housing  36  that is situated on a side of the second tine  21  generally opposite the first blade  30 . The housing  36  may take forms other than cylindrical as well as be positioned at different locations on and along the surgical retractor  10 . In this form, and as best seen in  FIG. 5 , the housing  36  is situated opposite to where the lower leg  32  of the blade  30  joins the second tine  21 . A light module or assembly  38  is releasably retained in the housing  36 . A retention flange  41  helps retain the light module  38  in the housing  36 . Particularly, the retention flange  41  is a small finger that protrudes out of the side of the light module  38  that will depress inwardly as it is pushed through the housing  36 . Once completely through the housing  36 , the flange  41  springs outwardly to lock the light module  38  in the housing  36 . The light module  38  includes a light source  39  that is preferably, but not necessarily, a light emitting diode (LED). Other types of light sources may be used and are contemplated. However, an LED generates little heat that could interfere with the surgery and is thus preferred, but other low heat or no heat generating light sources may be used. The LED  39  is electrically connected to an electrical power source, embodied as three (3) disk style batteries b 1 , b 2 , b 3  stacked upon one another to provide electrical contact between adjacent batteries. Other manners of providing electrical power may be used as well as other styles and/or number of batteries used. The batteries b 1 , b 2 , b 3  are biased against one another for electrical contact via an electrically conducting spring  70  or the like that is, in turn, electrically connected to the LED  39  in order to complete an electrical circuit for turning on the light. An insulator  17  (not shown in  FIGS. 5 and 6 , as the light module  38  is depicted in  FIGS. 5 and 6  in the on mode and therefore shining or projecting a beam of light LP), is provided that extends from the outside to the inside of the housing  36  and between the two batteries b 2  and b 3 . The insulator  17  creates an open circuit to the light electrical circuit so that the light is normally off. Removal of the insulator  17  by pulling it out of the housing completes the light electrical circuit to turn the light on. This is accomplished during use of the surgical retractor  10 . Other manners of interrupting and/or making contact between the batteries and the light source may be employed and are contemplated. 
         [0045]    The light module  38  is able to be positioned so as to shine the light beam emanating from the light source of the light module  38  on or at a particular area of the surgical retractor  10  and/or on or at a particular tissue or tissue area. While this may be achieved in various manners, the light module  38  of the surgical retractor  10  is able to rotate relative to the housing  36 , as indicated by the two-headed arrow on the top of the light module  38  of  FIG. 5 , such that the light beam or pattern LP (see  FIGS. 5 and 6 ) can shine upon a particular area of the surgical retractor  10  and thus a particular area of a muscle G, S, blade  30 ,  60  or incision (as indicated by the two, oppositely pointing arrows at the top of the light beam LP of  FIG. 5 ). Rotation of the light module  38  is accomplished by grasping the lower portion (essentially forming a knob) of the light module  38  that extends from the housing  36  and turning as desired. 
         [0046]    Another or additional manner of achieving light beam positioning is to allow the light module  38 , an equivalent thereof that holds the light source, or the light source itself, to move, slide or otherwise shift position along the surgical retractor  10  or a portion thereof. The light source may also move up or down, or angularly to likewise position the light beam. Still further manners are contemplated. 
         [0047]    Various Figures include lines and arrows delineating dimensions, component or part tolerances, or other features and/or aspects regarding one form of the surgical retractor  10 . It should be appreciated that these dimensions, component or part tolerances, or other features (e.g. specification of the surgical retractor) are exemplary and can change as necessary. For example, forms of the present surgical retractor  10  for muscles or tissues other than the gastrocnemius and soleus would necessitate a change in specification. 
         [0048]    In  FIG. 4 , dimension d 1  corresponding to 0.784 inches (19.91 millimeters) is given for the distance between the top of the light housing  38  and the bottom of the first tine  20 . In  FIG. 7 , dimension d 2  corresponding to 0.375 inches (9.53 millimeters) is given for the width of the second tine  21  (and of the first tine  20 ), while dimension d 3  corresponding to 0.250 (6.35 millimeters) is given for the height of the second tine  21  (and of the first tine  20 ). In  FIG. 8 , dimension of d 4  corresponding to 1.0 inches (25.4 millimeters) is given for the distance between the bottom of the upper leg  61  and the top of the lower leg  62  of the blade  60 , while dimension of d 5  corresponding to 1.50 inches (38.1 millimeters) is given for the distance between the top of the upper leg  61  and the bottom of the lower leg  62  of the blade  60 . In  FIG. 9 , dimension of d 6  corresponding to 0.200 inches (5.08 millimeters) is given for ratchet pitch for the serrations  24  of the first tine  20  and the serrations  80  of the finger  52  forming an upper ratchet mechanism, and for the serrations  25  of the second tine  21  and the serrations  81  of the finger  53  forming a lower ratchet mechanism. 
         [0049]    In  FIG. 10 , dimension d 7  corresponding to 0.911 inches (23.13 millimeters) is given for the width of the blades  30  and  60  at a line between the two arrows illustrating incision insertion width when the surgical retractor  10  is in the closed position, while dimension d 8  corresponding to 0.931 inches (23.64 millimeters) of width of the blades  30  and  60  at a line between the two arrows illustrating maximum retraction width when the surgical retractor  10  is in the closed position. In  FIG. 11 , dimension d 9  corresponding to 4.906 inches (124.62 millimeters) is given for the length of the blade  60 , and a radius r 1  corresponding to 11.394 inches (289.42 millimeters) is given for the radius of curvature of the blade  60 , dimension d 10  corresponding to 1.50 inches (38 millimeters) is given for the distance or length of retraction of the blade  60  relative to the blade  30  (tissue), and a radius r 2  corresponding to 5.89 inches (149.6 millimeters) is given for the radius of curvature of the blade  30 . 
         [0050]    The surgical retractor  10  is preferably, but not necessarily, ergonomically designed so that it can be inserted into a patient&#39;s incision by utilizing one&#39;s left or right hand. Particularly, when the surgical retractor  10  is in the closed or un-retracted position, the blades  30  and  60  are inserted into the incision. After insertion of the blades  30 ,  60 , the grooved tab  26  of the first retractor portion  12  is manipulated by the thumb while the second retractor portion  14  is grasped by the other hand. The surgical retractor  10  is manually retracted by the user to move the blade  60  away from the blade  30  to create a gap between the blades  30  and  60  for scalpel clearance. The upper and lower ratchet mechanisms incrementally ratchet along the first and second tines, preventing back movement of the carriage, and temporarily fixing position of the carriage and thus the second blade relative to the first blade. When the actuators  54 ,  55  are released, the upper and lower ratchet mechanisms will automatically hold the carriage  46  of the second retraction portion  14  and thus the blade  60  of the second retraction portion  14  relative to the first and second tines  20 ,  21  of the first retraction portion  14  and thus the blade  30  during surgery. The LED is actuated by removing the plastic insulator  17  that protrudes form the side of the housing  36 . This may be done before the blades  30 ,  60  are inserted into the incision. The LED is manipulated as appropriate to shine the light beam onto the desired incision area, muscle (tissue) and/or blade. Manipulation of the LED may be done as much as needed. Manipulation of the actuator  54 ,  55  releases the associated ratchets to allow the carriage  46  of the second retractor portion  14  and thus the blade  60  to be returned manually to a closed position. Other manners of utilizing the present surgical retractor  10  are contemplated and consistent with the present teachings. 
         [0051]    While the invention has been illustrated and described in detail in the foregoing drawings and description, the same is to be considered as illustrative and not restrictive in character, it being understood that only an illustrative form thereof has been show and described and that all changes and modifications that are within the scope of the following claims are desired to be protected.