Abstract:
A linear motion therapy device that has a single semi-enclosed worm-driven actuator (guide bar) with one end attached to a cantilevered and adjustable foot and heel support. The opposite end of the actuator is attached to a corset the person wears while in a supine position called a thoracic lumbar spine orthosis (TLSO). Next to the corset, but attached to the actuator is a motor, a height adjustment screw, and a stabilizer plate. A cord is attached to a push button hand control device for moving the foot support along the guide bar in a forward or reverse direction. Movement can be stopped at any time. A patient also wears a constraint that wraps around the thigh called a thigh support that attaches to the actuator with a pivotal and adjustable arm. This device can be adjusted to either leg.

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     Technical Field 
       [0001]    The presently claimed invention relates to therapy apparatuses, and more particularly, to a linear motion therapy device for enabling full range of motion for knee or hip problems. A mechanized linear motion therapy device (LMTD) is used after surgery for gentle knee or hip flexion and can be used on an inpatient or an outpatient basis. 
       Background Art 
       [0002]    There are several devices in the marketplace for providing physical therapy to a patient after knee or hip surgery; however, most of these devices are for use right after surgery. 
         [0003]    Some of these include: Continuous passive motion (CPM) devices are used during the first phase of rehabilitation following a soft tissue surgical procedure or trauma. CPM is carried out by a CPM device, which constantly moves the joint through a controlled range of motion and provides passive motion in a specific plane of movement. The shortcomings of CPM machines are that they are used only immediately after surgery and up to four weeks afterwards; the device is heavy and difficult for some people to handle when sitting on a surface, it tilts to one side or another, and it is difficult to fit properly for a person with less than a twenty five inch (25″) leg length. Therapeutically, it only approximates calibration of the flexion of the knee, tends to move away from the person using it, thus, not targeting the knee joint which needs to be bent. The CPM spends little time at the height of the knee flexion or at extension because of its continuous motion action and does not completely extend the leg to put femur and tibia into traction for some patients. 
         [0004]    Manual therapy is currently being used which includes heel slides whereby the patient lies with his or her back while on a table, bed, or floor with a strap or fastener under the foot and slides the heel closer to the buttocks while holding the strap. When the patient can no longer bend the knee on his/her own, he/she pulls on the ends of the strap to flex the knee further. A physical therapist assistant (PTA) or physical therapist (PT) can also push on the leg to get the maximum flexion. The PTA or PT may then measure the amount of flex with a goniometer. Another in-house therapy method includes use of a heel prop whereby the patient lies on his or her back while on a table, bed, or floor with the postoperative leg fully extended. The heel of this leg is placed on an item such as a rolled up towel, a half-round plastic roll, or other object that keeps the knee fully extended and clears the girth of the calf. At home, the patient may not do the exercises as prescribed; may do them improperly, or not at all. Further, it requires the time of a PT or PTA to teach and then observe to make sure that the patient does the therapies properly. 
         [0005]    NK™ tables are also used for therapy. A patient sits on the NK™ table and the postoperative knee/hip is strapped down at the thigh. The knee is then bent to a degree that the patient can tolerate. A long bar with a perpendicular bar to hold weights is attached at the end. Weights are added as needed for resistance to keep the bend. The entire long bar can be adjusted according to the type of bend required. Set up time takes a very long time and cannot be used in a home setting. It does not keep the hip from hiking (moving up) nor does it keep the patient from leaning side to side, thus, keeping the knee from flexing properly or in correct alignment. This device takes time for a PT or PTA or technician to get the patient set up, adjust the device, place the proper weights on the machine, and it cannot be used at the patient&#39;s home. 
         [0006]    The prior art devices fail to allow a patient to get a true bend and precisely measure the bend. The measurement of bend provides positive reinforcement and motivation to a patient. The presently claimed invention provides a positive environmental setting whether at a therapy location or at home. It is also important because the patient has a very short window of time to improve the bend and break through scar tissue. The thoracic lumbar spine orthosis (TLSO)/back support and thigh support in the presently claimed invention, keep the patient in the correct position unlike manual therapy or slides, which allow too much side to side movement and can also move away from the bend. These aforementioned prior art therapies are inconsistent. Without daily practice, the patient may not improve and once or twice a day is not enough to continue improvement. The claimed invention is for use four weeks after surgery, and is not continuously, but manually controlled by the patient using the device. Further, the claimed invention is adaptable to each patient, and is relatively light (20 pounds) which makes the apparatus easy to handle. 
       SUMMARY OF THE INVENTION 
     Disclosure of the Invention 
       [0007]    The presently claimed invention solves the aforementioned problems and shortcomings of the prior art by providing a lightweight and inexpensive therapy apparatus and method for an ever increasing range of motion for the postoperative patient. More particularly, the presently claimed invention is for use after the first four weeks postoperative inpatient or outpatient use. 
         [0008]    In one embodiment the linear motion therapy apparatus comprises a base with a driven worm-drive, a thoracic lumbar spine orthosis (TLSO) affixed to the base, a thigh support assembly affixed to a movable arm, the moveable arm affixed to the base, a footpad assembly affixed to a worm receiver disposed on the worm-drive and an apparatus to provide clockwise and counterclockwise rotation to the worm-drive and provide telescopic linear movement to the footpad assembly. The footpad assembly can be a pivoting footpad and have at least one strap to secure a foot inserted into the footpad and a heel cup and have at least one stop to prevent the footpad from pivoting beyond a predetermined number of degrees. The footpad assembly can have a removable foot support for affixing to the footpad assembly for a left or a right foot. The TLSO can be removable for affixing to the base in a right or a left leg configuration. The TLSO can also be a two piece rigid outer shell with a plurality of shell apertures for adjusting the two piece outer shell for different sized torsos, have attachment assemblies on either side of the two piece outer shell assembly for affixing to the base for either the right or the left leg configuration, a cushion material disposed on an inside of the two piece outer shell, and at least one adjustable fastener to tighten and loosen the TLSO. The thigh support assembly can be a rigid semi circular support with cushion material disposed on an inside of the support and at least one adjustable thigh support fastener to secure and release a thigh. The moveable arm can have at least one aperture for affixing the adjustable arm to the base for a right or a left leg configuration, configured to allow the adjustable arm to move vertically and have a plurality of adjustment apertures to allow the thigh support assembly to accept different leg lengths. The apparatus to provide clockwise and counterclockwise rotation to the worm-drive can be a motor with controls to rotate the worm-drive in a clockwise or counterclockwise direction and to start and stop the rotation. The linear motion therapy apparatus can have supports affixed to the base to keep the base at a predetermined height above a surface. The linear motion therapy apparatus can have a measuring apparatus affixed to the base to measure a range of motion. 
         [0009]    In another embodiment, a method for providing physical therapy targeted to a knee joint with a linear motion therapy device provides a base comprising a driven worm-drive, a thoracic lumbar spine orthosis (TLSO) affixed to the base, a thigh support assembly affixed to a movable arm, the moveable arm affixed to the base, a footpad assembly affixed to a worm receiver disposed on the worm-drive, and an apparatus to provide clockwise and counterclockwise rotation to the worm-drive. This also provides telescopic linear movement to the footpad assembly, placing the patient into the linear motion therapy device, activating the apparatus to provide rotation to the worm-drive in a first direction, deactivating the apparatus to provide rotation to the worm-drive, activating the apparatus to provide rotation to the worm-drive in a second direction, and deactivating the apparatus to provide rotation to the worm-drive. The method can also include configuring the TLSO, the thigh support assembly, and the footpad assembly for a selected leg. The method can also include adjusting the TLSO and thigh support assembly to fit the patient&#39;s torso and thigh, telescopically adjusting the footpad assembly to where the patient is able to place the foot on the footpad assembly, tightening foot support straps, tightening thigh support straps, and tightening TLSO support straps. The method of pushing at least one button and deactivating comprises releasing the at least one button on a hand held controller or pushing up on a first button to activate the motion in the first direction and pushing down on a second button to activate the motion in the second direction. The method can also include looking at a measurement indicator affixed to the base that corresponds to a location of the footpad assembly. This can also include the step of preventing the patient&#39;s back and hips from lifting off a surface when the TLSO is activated via the TLSO and allowing the patient&#39;s thigh to move vertically when the TLSO is activated via the thigh support. 
         [0010]    An object of the presently claimed invention is to provide a versatile apparatus for increasing the patient&#39;s range of motion in the knee or hip. Another object of the claimed invention is to provide a therapy apparatus that can be used in an inpatient or outpatient setting and is adjustable to keep all parts in correct alignment for different sized individuals, accommodating either the right leg or left leg. 
         [0011]    Advantages of the presently claimed invention are that the apparatus will decrease soft tissue stiffness and limit the continuing development of scar tissue. Another advantage is that it prevents an anterior pelvic tilt to eliminate increased lordosis and external rotation of the hip keeping the leg in alignment and emphasizing the knee bend without the leg moving medially or laterally. 
         [0012]    Other objects, advantages and novel features, and further scope of applicability of the presently claimed invention will be set forth in part in the detailed description to follow. They will be taken in conjunction with the accompanying drawings, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the claimed invention. The objects and advantages of the claimed invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The accompanying drawings, which are incorporated into and form a part of the specification, illustrate several embodiments of the present invention, and together with the description, serve to explain the principles of the invention. The drawings are only for the purpose of illustrating a preferred embodiment of the invention and are not to be construed as limiting the invention. In the drawings: 
           [0014]      FIG. 1A  is a perspective view of the preferred embodiment of the linear motion therapy device. 
           [0015]      FIG. 1B  is a cut out view along A-A of  FIG. 1A . 
           [0016]      FIG. 2  is another perspective view of the linear motion therapy device affixed to a patient in a retracted position. 
           [0017]      FIG. 3  is a perspective view of the linear motion therapy device affixed to a patient in an extended position. 
           [0018]      FIG. 4  is a right side view of the preferred linear motion therapy device. 
           [0019]      FIG. 5  is a left side view of the preferred linear motion therapy device. 
           [0020]      FIG. 6  is a top view of the preferred linear motion therapy device. 
           [0021]      FIG. 7  is an exploded top view of the preferred footrest and its removable attachment to the rail. 
           [0022]      FIG. 8A  is an exploded top view of the preferred exchangeable thoracic lumbar spine orthosis (TLSO) and its removable attachment to the rail. 
           [0023]      FIG. 8B  is a rear view of  FIG. 8A  showing the two-piece outer layer and adjustment area. 
           [0024]      FIG. 9  is an exploded view of the motor and foot. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Best Modes for Carrying out the Invention 
       [0025]      FIG. 1A  is a perspective view of the preferred embodiment of the linear motion therapy device (LMTD)  10  for use after surgery or trauma for rehabilitation of a knee, hip or ankle.  FIG. 4  is a right side view of the preferred linear motion therapy device of  FIG. 1A .  FIG. 5  is a left side view of the preferred linear motion therapy device and  FIG. 6  is a top view of the preferred linear motion therapy device. This apparatus is designed for use four to six weeks after trauma or surgery. As shown in the aforementioned figures, base or rail  12  is preferably constructed from metal such as aluminum; however, any strong material can be used. Disposed inside the base is threaded rod  14  with a first end  16  affixed to a motor  18  which supplies rotational force to worm-drive or threaded rod  14 , as more clearly shown in  FIG. 1B , which is a cut out view of A-A of  FIG. 1A . Motor  18  is preferably electrically driven. Second end  100  of threaded rod  14  is disposed in a bearing or cup  20 , allowing the rotational movement  22  of threaded rod  14 . Disposed onto threaded rod  14  is a nut or worm receiver  24 , which is affixed to footpad assembly  26  and provides telescopic linear movement  28  of footpad assembly when threaded rod  14  is rotated. A longitudinal slot  38  on a top end of base  12  allows for worm receiver  24  to traverse from front to back in a linear fashion. Front end of base  30  has a first base support  32 , which is shown as a triangular member to keep LMTD  10  from rocking when in use. Back end of base  34  is a second or rear base support or foot  36 . Foot  36  can be affixed to back end of base or to motor  18  which is affixed to back end of base  34 , as shown. First base support  32  and foot  36  keep base  12  at a predetermined height above the surface, such as a table, floor, bed, or the like. Preferably motor  18  rotates worm-drive in a clockwise and counterclockwise direction and the direction is based on a hand held control  40  which can be directly wired to motor  18  or wirelessly controlled. Any other type of device such as a hand crank or the like can be used to provide rotational movement to worm-drive. A measurement indicator  98  can be included on one or both sides of rail  12  in inches and/or centimeters to measure the range of motion. 
         [0026]    In addition to  FIGS. 1A ,  4 ,  5 , and  6 ,  FIG. 7  shows the preferred footpad assembly  26 . Affixed to worm receiver  24  is a carriage  42 . Carriage  42  moves linearly in a front or back motion  44  as previously described. Removeably affixed to carriage  42  is foot support or footrest  46 . Footrest  46  can be mounted to carriage  42  for a right foot or left foot by placing foot-rest  46  in the selected position and inserting pin  100  through an aperture in carriage  42  and into receiver aperture  48  in footrest  46 . Pin  102  can have a spring-loaded ball on the end to keep it engaged. Pin  102  can also have a lanyard  50  affixed to carriage  42  as shown to prevent loss or misplacing it. Carriage  42  preferably has a stop  52  to keep footrest  46  from tilting more than  30  degrees or keep foot in plantar flexion. Footrest  46  preferably has a heel cup  54  to keep a patient&#39;s heel in place. Two straps  56  and  56 ′ support the foot in footrest  46 , strap  56  configured for ankle support, and second strap  56 ′ configured to support the widest part to secure foot firmly with ankle starting in neutral position. Straps  56  and  56 ′ are preferably made from a cloth or cloth-like material and are fastened with hook and loop fasteners or the like. 
         [0027]      FIGS. 1A ,  4 ,  5 , and  6  show the preferred thigh support assembly  58 . Thigh support assembly  58  is configured to support the thigh portion of a leg while the footrest  46  is telescopically moving. Thigh support assembly  58  is preferably a plastic molded semicircular support  60  with a cushion material  62  affixed to the inside for a patient&#39;s comfort. Two straps  64  are affixed with hook and loop fasteners around thigh support  60  to keep it snugly against a patient&#39;s thigh. Thigh support is affixed to an adjustable arm  66  on an adjustable arm first side  70  with bolts and nuts or the like. A plurality of adjustment apertures  68  is on adjustable arm  66  to conform to various leg sizes. An adjustable arm second side  72  is affixed to an interchangeable receiver  74 , which can be used on a right or left side. Interchangeable receiver  74  is bolted or clamped onto base  12 , as shown. Adjustable arm  66  is configured to move thigh support assembly  58  vertically in unison with the linear movement of footrest  46 . 
         [0028]      FIG. 8A  is an exploded view of the preferred TLSO  76 . TLSO is configured to support a patient&#39;s back and hips. This assembly keeps the patient&#39;s back and hips from lifting off the surface when a patient is bringing a knee into knee flexion. This configuration protects the back from other ailments such as stenosis, back pain, or the like. TLSO  76  preferably has an outer shell  78 , which is a two piece semi rigid flexible material, such as plastic, that are oval shaped with a slit on the front side. As shown in  FIG. 8B , by using two pieces, the back of the outer shell can be adjusted to fit differing sized torsos. Referring again to  FIG. 8A , shell apertures  80  can be aligned or bolted together to vary the size of the shell as shown. Within outer shell  78  is a cushion type material  82 , such as an Orthowick® liner which is hypo allergenic, for a user&#39;s comfort when TLSO  76  is worn and tightened. TLSO straps  84 , comprising hook and loop fasteners, or the like are tightened around outer shell  78  to keep it firmly around the torso and to keep the patient&#39;s back and hips from lifting off the table or surface when patient is bringing the knee into knee flexion. Affixed to either side of outer shell  78  are attachment assemblies  86  and  86 ′. These assemblies are preferably constructed from a highly resilient material such as aluminum, steel or the like, and with an assembly affixed to a right side and another to a left side. Each attachment assembly  86  has a receiver  88  for receiving a bolt  90 , pin, or the like to removably attach TLSO  76  to variable connector  92 . Variable connector  92  is configured to connect bolt  90  to either a right side attachment assembly  86  or a left side attachment assembly  86 ′. The embodiments shown in  FIGS. 8A and 9  show a slotted receiver  94  on motor or motor mount with the head of bolt  90  in the slot, allowing bolt  90  to be swung from one side to the other  96  to affix to the proper attachment assembly  86 . This embodiment is configured to accommodate either a right leg or a left leg and can be easily changed to accomplish this with very few steps. Additionally, the LMTD  10  is configured to accommodate virtually all sizes of patients with its adjustability. 
         [0029]      FIGS. 2 and 3  show the operation of the LMTD  10 . First, the LMTD is configured for the correct leg as described above and adjusted or sized to fit the patient. LMTD  10  is placed on the floor, therapy table, or bed with enough room for the patient to lay supine and plug the electrical cord into an electrical outlet. Next, foot support assembly  26  is adjusted by telescopically moving it into a position where the knee is comfortable and the patient is able to place foot on foot support. The patient lies within TLSO  76  and the thigh support  58 , with the foot placed on the foot support  46 . Patient or caregiver straps the foot first, then the thigh, followed by the TLSO so that it is snug to the patient&#39;s waist. Patient can now begin bending the knee. Using the hand control device  40 , the patient, PT or PTA can push the up arrow to begin flexing the knee. The patient may stop the device by releasing (taking a finger off) the up or down button. This allows the patient to completely control how much flex is being allowed and can accommodate the patient&#39;s pain level. Patient can continue or reverse the machine (using the down arrow) striving for a maximum range of motion. The patient can also see his/her progress by looking at the measurement indicator  98  on the side of rail  12  that corresponds to the location of carriage  42 . 
         [0030]    Although the claimed invention has been described in detail with particular reference to these preferred embodiments, other embodiments can achieve the same results. Variations and modifications of the presently claimed invention will be obvious to those skilled in the art and it is intended to cover in all such modifications and equivalents. The entire disclosures of all references, applications, patents, and publications cited above, are hereby incorporated by reference.