CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation-in-part of U.S. patent application Ser. No. 12/469,671, filed May 20, 2009, the disclosure of which is hereby incorporated by reference. 
    
    
     FIELD 
     The invention relates to a knee orthosis. More particularly, it refers to a pre-operative, post operative knee orthosis for stabilizing a knee joint of a person before or after surgery or after injury thereto, that applies an adjustable corrective and therapeutic force to the knee joint and surrounding muscles above and below the knee and which also removes pressure from a lower shin cuff of the knee orthosis when a patient using the novel knee orthosis of this present invention flexes the knee joint or performs a body squatting motion through rotation about a shin cuff hinge. 
     Background 
     Orthosis devices and appliances commonly referred to as “orthotics,” are known in the prior art and have been utilized for many years by orthotists (a maker and fitter of orthotics), physical therapists, and occupational therapists to assist in the rehabilitation of a patient&#39;s joints and associated limbs or adjacent skeletal parts of the patient&#39;s body related to a variety of conditions. An early example can be seen in U.S. Pat. No. 3,581,741 to Rosman, which discloses a knee brace comprising an upper rigid body portion and a lower rigid body portion pivotably coupled together on the lateral side in a manner so that they may pivot relative to each other about an axis generally perpendicular to the zone of overlap and may slide relative to each other in all radial directions generally parallel to the zone of overlap. 
     Webster&#39;s New College Dictionary defines “orthotics” as a branch of mechanical medical science that deals with the support and bracing of weak or ineffective joints or muscles. The word “ortho” actually comes from Greek and means “to straighten.” Orthotics are used to support, straighten, and stabilize affected joints and assist to correct normal human function as closely as possible. Orthotics used as knee braces have typically been designed to support and protect the knee joint that is associated with a variety of knee joint conditions, for alleviating pain associated with joint movement at the particular location being treated or for immobilizing the knee joint so that movement thereof in either the medial or lateral directions or rotation of the knee is eliminated or at least significantly reduced. 
     Repetitive use of a joint, such as the knee, over time tends to reduce the stability of the knee. In cases of injury through accident or sports related causes, instability of the knee can be exacerbated and worsened to the point that without immobilization or support of the knee joint by an orthotic, a person cannot bear the weight of their own body upon the knee joint. Or to do so results in great pain, which is usually treated with pain medications that can be addictive and hard on the liver and other important organs of the body. Further, when there is a lack of movement of a patient due to knee instability, a sedentary lifestyle is usually taken up, which can result in a reduction of body energy, weight gain, atrophied muscles concentrated around the knee joint, and a general depression of mental state due to the lack of ability of the person to be self-sufficient and mobile. 
     Therefore, it can be plainly seen that knee orthotics of all types are useful if they assist a person in returning to a more normal lifestyle or at least one that is significantly less sedentary when compared to the immobile person with an instable knee. It can be said that proper use of the knee joints is essential to complete body health and a proper state of mind. 
     It is well known, as complaints are abundant, that not all knee orthotics or braces that stabilize the knee are comfortable to wear. In fact, most knee orthotics apply unwanted pressure to the thigh and the shin of the patient when the patient walks, squats, or flexes the knee joint. This is because all prior art knee orthotics are typically made from very hard and rigid materials that do not flex and move with the changing conditions of the body (i.e., expansion and contraction of the leg musculature). Such areas of change include the knee joint area and the upper and lower leg when the patient is walking, flexing, or squatting. This can be particularly seen with the shin cuff that applies a great amount of pressure against the shin of the patient when the patient squats. This pressure, therefore, discourages the patient from performing any squatting action, which in turns encourages the patient to remain sedentary, resulting in the degradation of physical and mental state. 
     Further, prior art knee orthotics do not apply therapeutic and corrective forces to the knee joint area and the surrounding leg musculature area. Such is needed in combination with a flexible and pliable brace that incorporates a system for reducing or eliminating pressure placed against the shin of the patient when the patient walks or flexes the knee joint or when he squats his body. This can also include alone or together a system for reducing or eliminating pressure placed against the thigh of the patient when the patient walks or flexes the knee joint or when he squats. The specific elements that accomplish such pressure elimination include, in the present invention, flexible and pliable materials for one or both the shin or thigh cuffs, and hinged shin and thigh cuffs that permit rotation from a 90 degree position to a degree of at least 45 degrees, if not further. 
     Summary 
     The knee orthosis of the present invention provides all of the advantages needed, which are mentioned above and that are currently deficient and wholly missing from the prior art. The present knee orthosis is used and indicated for increased medial, lateral, and rotational support and control of the knee joint following injury to, or reconstruction of, the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL), or protection of the collateral ligament of the knee. The present invention provides increased support for patients who have continued symptoms of significant knee instability such as giving way, which may be due to poor quadriceps or hamstring strength (i.e., hemiplegia), or for patients who have a desire to quickly resume activities after knee surgery. The present knee orthosis is also useful after total knee replacement or high tibia osteotomy. 
     To provide the above set forth benefits and improvements over the prior art, the present knee orthosis device includes two vertical struts, positioned on opposed sides of a knee joint in a generally parallel relationship, wherein each vertical strut has a hinge member located at a general middle portion thereof, and further wherein each vertical strut has a top and bottom end portion. Both polycentric and uni-centric hinges can be employed for the two hinges members, in any combination thereof. An upper thigh cuff attached at opposed ends to the upper end portions of the two vertical struts provides a means to secure the knee orthosis to the thigh of the patient. A secondary thigh strap is also employed to provide additional securing means and is positioned slightly below the thigh cuff. The thigh cuff is positioned posterior to the thigh, whereas the secondary thigh strap and a strap used to secure the thigh cuff are both positioned anterior to the thigh of the patient. 
     A shin cuff attaches at opposed ends to the lower end portions of the two vertical struts and is positioned anterior to the shin. The shin cuff has a strap member that wraps around the back of the shin of the patient for securing it to the patient&#39;s shin. A secondary shin strap is positioned slightly above the shin cuff but is positioned on the posterior side of the shin area of the patient. 
     The lower shin cuff has a pair of hinges located proximal to the shin cuff opposed ends and left and right vertical strut lower end portions for permitting the shin cuff to pivot downwardly away from a shin of a person wearing the knee orthosis when a person flexes the knee or performs a squatting motion thereby reducing or eliminating unwanted pressure that is usually applied to the shin of a patient of a person when they flex the knee, walk or squat. The shin cuff can pivot upwards of 60-75 degrees. 
     The novel knee orthosis of the present invention also employs a plurality of air bladders used as therapeutic  7  and corrective force elements for the device. The air bladders are removably positionable along inner surfaces of the two vertical struts and hinges. Any number from one to six air bladders can be employed such that force can be applied on both sides of the knee joint, at the knee joint, directly above the knee joint on the inner and outer thigh area and directly below the knee joint on the inner and outer shin area. When employed the air bladders also provide additional stabilization to the knee, prevent brace slippage and provide an extra degree of comfort to patient. 
     The novel knee orthosis also employs elastic thigh and cuff cushion members positioned along the inner surfaces of the thigh and shin cuff, respectively, for providing more comfort and support. The elasticity of these cushions allows them to bend and flex with the movements of the patient but return to their stable positions after movement by the patient such that the patient&#39;s knee joint is continuously stabilized regardless of the movement made by the patient using the knee orthosis of the present invention. 
     In a first alternate embodiment, the upper thigh cuff also has a pair of hinges located proximal to the thigh cuff opposed ends and left and right vertical strut upper end portions for permitting the thigh cuff to pivot upwardly away from a thigh of a person wearing the knee orthosis when a person flexes the knee or performs any other motion thereby reducing or eliminating unwanted pressure that is usually applied to the thigh of a patient of a person when they flex the knee, walk or squat. The thigh cuff can pivot upwards of 60-75 degrees or more. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention can be best understood by those having ordinary skill in the art by reference to the following detailed description when considered in conjunction with the accompanying drawings in which: 
         FIG. 1  is a left side perspective view of the knee orthosis of the present invention; 
         FIG. 2  is a right side perspective view of the knee orthosis of the present invention; 
         FIG. 3  is a front view of the knee orthosis of the present invention illustrating the shin cuff located at a lower end of the knee orthosis; 
         FIG. 4  is a front view of the knee orthosis of the present invention illustrating the thigh cuff located at an upper end of the knee orthosis; 
         FIG. 5  is a left side view of the knee orthosis of the present invention illustrating a polycentric hinge and deflection guide of a left side vertical strut and a left side shin cuff hinge; 
         FIG. 6  is a right side view of the knee orthosis of the present invention illustrating a uni-centric hinge and of a right side vertical strut and a right side shin cuff hinge; 
         FIG. 7  is a left side view of the knee orthosis of the present invention illustrating how the shin cuff angles downwardly away from a horizontal plane; and 
         FIG. 8  illustrates the inflation tubes of the air bladders used in conjunction with knee orthosis of the present invention as the therapeutic and corrective force employed to the knee joint area and the surrounding leg musculature. 
     
    
    
     DETAILED DESCRIPTION 
     Throughout the following detailed description the same reference numerals refer to the same elements in all figures. 
     Referring to  FIGS. 1 and 2 , a knee orthosis  10  of the present is shown. As shown, knee orthosis  10  has a left side and right side vertical strut,  12  and  14 , respectively. Struts  12  and  14  are generally parallel and when knee orthosis  10  is employed on a patient, run along medial and lateral sides of a knee joint and thigh and shin area of the patient. Each strut has its own hinge  16  and  18  positioned intermediate top and bottom portions of struts  12  and  14  such that knee orthosis  10  pivots about said hinges when the knee joint of the patient is flexed. In the embodiment shown in  FIGS. 1 and 2 , hinge  16  is a polycentric hinge and hinge  18  is a uni-centric hinge. However, nothing herein limits the use of knee orthosis to this embodiment shown and described herein in this preferred embodiment could be employed. In fact, any combination of hinges could be employed. 
     Referring to  FIG. 3 , and also with continuing reference to  FIGS. 1 and 2 , an anterior positioned shin cuff  20  is shown that has opposed ends  22  and  24 . Shin cuff opposed ends  22  and  24  attach to lower ends  26  and  28  of left and right side vertical struts  12  and  14 . Attached along an inner surface (not shown) of shin cuff  20  is a flexible shin cushion pad  30  which is removably attached to said shin cuff  20  inner surface. Shin cuff cushion  30  is very pliable, with a shape capable of being manipulated and then able to return to its normal resting state, as shown in  FIG. 3 . It is attached to shin cuff  20  inner surface by hook and loop material. 
     With continuing reference to  FIG. 3 , it is shown that shin cuff  20  has a shin cuff strap  32  that wraps behind the shin of a patient for securing thereto. Further, a secondary shin strap  34 , with a positionable cushion pad  36 , is positioned slightly above shin cuff strap  32  and is used to provide extra securing means for the knee orthosis  10  to the patient. Both shin cuff strap  32  and secondary shin strap  34  each have opposed ends which loop through D-rings (see  FIGS. 5 and 6 ) and then attach to themselves by hook and loop material. 
     Referring now to  FIG. 4 , and also with continuing reference to  FIGS. 1 and 2 , a posterior thigh cuff  38  is shown that has opposed ends  40  and  42 . Thigh cuff opposed ends  40  and  42  attach to upper ends  44  and  46  of left and right side vertical struts  12  and  14 . Attached along an inner surface (not shown) of thigh cuff  38  is a flexible thigh cushion pad  48  that is removably attached to thigh cuff  38  inner surface. Thigh cuff cushion pad  48  is very pliable, with a shape capable of being manipulated and then able to return to its normal resting state, as shown in  FIG. 4 . It is attached to thigh cuff  38  inner surface by hook and loop material. 
     With continuing reference to  FIG. 4 , it is shown that thigh cuff  38  has a thigh cuff strap  50  which wraps in front of the thigh of a patient for securing thereto. Further, a secondary thigh strap  52 , with a positionable cushion pad  54  is positioned slightly below thigh cuff strap  50  and is used to provide extra securing means for the knee orthosis  10  to the patient. Both thigh cuff strap  50  and secondary thigh strap  52  each have opposed ends which loop through D-rings (see  FIGS. 1 and 2 ) and then attach to themselves by hook and loop material. 
     Referring now to  FIG. 5 , it is shown that polycentric hinge  16  includes a deflection guide  56 , which optionally includes a plurality of setting blocks  58  and a tensile member  60 . The tensile member  60  is attached at opposed ends to knee orthosis  10 , and stretches over the plurality of setting blocks  58  to provide a force to knee orthosis  10  to assist patients in gait kinetics and musculature exercise. The tensile member  60  may be any component capable of providing a tensile force, including but not limited to one or more elastic bands, o-rings, coil springs, rubber bands, or resilient member. 
     The deflection guide  56  acts to keep the tensile member  60  some distance away from the axis of rotation of the hinge  16 / 18 . If the tensile member is allowed to move beyond the hinge  16 / 18  it either becomes ineffective by providing no extension force, or counter-productive by creating a bending, rather than extending, force. 
     Nothing herein limits the use of only one deflection guide  56 , nor does anything herein limit which side deflection guide  56  is employed in the case that only one deflection guide  56  is employed with knee orthosis  10 , as shown in the preferred embodiment. 
     When a strut  12 / 14  is bent across hinge  16 / 18 , the deformation/elongation of tensile member  60  provides a force to aid in leg extension, or straightening of the knee joint. In some examples, the tensile member  60  is in a contracted or relaxed state when the strut  12 / 14  is in a generally parallel relationship, and in an extended or stretched state when the strut  12 / 14  is in a generally bent. As a result of creating a force that aids in leg extension, the tensile member  60  acts as a motion accelerating mechanism. The force that is created by the tensile member  60  is either a constant force regardless of length through use of a constant force spring or equivalent, or more commonly the force increases as the tensile member  60  experiences greater deformation/elongation. 
     Referring now to both  FIGS. 5 and 6 , it is shown that knee orthosis  10  also includes a shin cuff hinge assembly  62  on both left and right lower ends,  26  and  28 , of left and right vertical struts,  12  and  14 . Each shin cuff hinge assembly  62  contains a pivoting axis  64 , a setting block  66  and a shin tensile member  68 , attached at opposed ends to knee orthosis  10 , for stretching over setting block  66 . The shin tensile member  68  may be any component capable of providing a tensile force, including but not limited to one or more elastic bands, coil springs, rubber bands, or resilient member. As shown in  FIG. 7 , shin cuff  20  pivots downwardly about both axis  64 , so that shin cuff  20  reduces the pressure applied against the shin of the patient when he walks, flexes his knee or squats down. Shin tensile member  68  provides a means to return shin cuff  20  to its normal resting state when the patient ceases to walk, flex his knee or squat down. 
     Referring back to  FIGS. 1 and 2 , it can be seen that a plurality of air bladders  70  are employed along inner surfaces of the left and right vertical struts  12  and  14 . Bladders  70  are attached to knee orthosis  10  by hook and loop material and are therefore removably attachable. Although only four air bladders  70  are shown, nothing herein limits the use of more or less than four bladders. For example, in an alternate embodiment, six air bladders  70  are employed to provide corrective and therapeutic force to the knee joint area at the knee joint on both sides, above the knee joint on both sides and below the knee joints on both sides. 
     Referring to  FIG. 8 , a set of inflation tubes  72  are shown, which are used to inflate or deflate air bladders  70  depending on therapist or patient preferences. 
     In the preferred embodiment, knee orthosis  10  is made from highly pliable, semi-rigid materials that permit knee orthosis  10  to bend, flex, and move with the movements of the patient, but all the while maintaining the knee in a completely stabilized and immobile state. However, nothing herein limits the use of more rigid, less pliable materials if necessary. 
     Although not shown, the upper thigh cuff can also employ a pair of hinges located proximal to the thigh cuff opposed ends and left and right vertical strut upper end portions for permitting the thigh cuff to pivot upwardly away from a thigh of a person wearing the knee orthosis when a person flexes the knee or performs any other motion thereby reducing or eliminating unwanted pressure that is usually applied to the thigh of a patient of a person when they flex the knee, walk or squat. The thigh cuff can pivot upwards of 60-75 degrees or more. The present invention can employ a hinged shin cuff, a hinged thigh cuff, or both a hinged shin and hinged thigh cuff. 
     Equivalent elements can be substituted for the ones set forth above such that they perform in substantially the same manner in substantially the same way for achieving substantially the same result. 
     It is believed that the system and method as described and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely exemplary and explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.
A disclosed knee orthosis has two vertical struts positioned on opposed sides of a knee joint in a generally parallel relationship. Each vertical strut has a hinge member located at a general middle portion; each vertical strut has a top and bottom end portion. An upper thigh cuff attaches at opposed ends to the upper end portions of the two vertical struts whereas a lower shin cuff attaches at opposed ends to the lower end portions. The lower shin cuff has a pair of hinges located proximal to the shin cuff opposed ends for permitting the shin cuff to pivot downwardly away from a shin of a person wearing the knee orthosis. An alternate embodiment employs hinges located proximal to the thigh cuff opposed ends for permitting the thigh cuff to pivot upwardly away from a thigh of a person when the same motion is performed.