Patent Document

CROSS REFERENCE TO RELATED APPLICATION 
   This application is based upon Provisional Patent Application 60/570,132, filed May 10, 2004, the contents of which are herein incorporated by reference. 

   FIELD OF THE INVENTION 
   This invention relates to continuous passive motion therapy devices for flexing joints through a selected range of motion. 
   DESCRIPTION OF THE PRIOR ART 
   Patients of knee, hip and other joint surgeries have long been shown benefit from immediate therapy and motion of the joint under treatment. Therapy may be prescribed by orthopedic surgeons following total knee replacement, anterior cruciate ligament reconstruction, tendon repair, joint manipulation under anesthesia, arthrosporic debridement of adhesions, open reduction and interior fixation (stabilization) of intra-articular fractures, articular cartilage micro fracture, and articular cartilage transplantation. However, automation of such joints can be near impossible immediately following surgery due to invasive and, often, destructive procedures. Continuous Passive Motion (hereinafter referred to as, CPM) machines were developed that allow a patient to immediately start to exercise such joints and begin the healing process. Passive range of motion is defined by articulating the joint without the patient&#39;s muscles being used. There are CPM devices for the knee, ankle, shoulder, elbow, wrist and hand. 
   In today&#39;s health care environment in which hospital discharge is nearly immediately after surgery, patients can benefit from a device that is also suitable for home use. Current state of the art therapeutic machines for treatment of the leg, knee, and hip illnesses or surgery are large stationary devices that are not well suited for patients in-home use. The devices are relatively heavy and require the patient to lie prone to utilize the device. 
   For example, U.S. Pat. No. 4,549,534 to Zagorski et al; U.S. Pat. No. 4,930,497 to Saringer; U.S. Pat. No. 5,280,783 to Focht et al.; U.S. Pat. No. 5,399,147 to Kaiser; U.S. Pat. No. 6,325,770 to Beny et al.; U.S. Pat. No. 6,743,187 to Solomon et al.; and published U. S. Patent Application, Pub. No. US 2003/0120186 A1 to Branch et al., all disclose a CPM device with a long heavy base connected to an articulated frame for manipulating the body member and a mechanical system for moving the frame along the tract. 
   SUMMARY OF THE INVENTION 
   A lightweight portable therapy device which attaches to the patient for flexing a joint through a range of motion. A patient can use this system post-operatively and upon release from the hospital, the device can be used at home to assist in patient recovery. In a particularly preferred embodiment, the device employs a modular frame construction that can be either folded or separable into at least two modules defined as a proximal sling module and a distal sling module. 
   In another embodiment, the device can include a base module. The base module having a link with one end of the proximal sling module pivotally connected to one end of the distal sling module to provide range of motion. The other end of the proximal sling module is pivotally connected to one end of the base module while the other end of the distal sling module is pivotally connected to one end of the link. The end of the link is pivotally connected to the base intermediate to one end of the base and the bottom. In each of the aforementioned embodiments, the modules include removable connectors cooperating with each of the pivotally connected ends whereby removal of the connectors permits disassembly of the modular frame. 
   Therefore, it is an objective of this invention to provide a CPM device that is lightweight, portable, user friendly, multi-functional and that is easy to use by health care providers and patients. 
   It is another objective of this invention to provide a CPM device that can be used by the patient in a reclining position, prone position or a sitting position. 
   It is yet another objective of this invention to provide a portable, lightweight, low voltage, high torque motor and controller supplied power by either battery operation or connected to an electrical grid. 
   It is another objective of this invention to provide a set of limit parameters in the controller, including a signaling device, to perform a safety shut-down or pause due to anomalies occurring in the programmed routine. 
   It is a further objective of this invention to provide a controller and control module with wireless communication capability. 
   It is a still further objective of this invention to provide a CPM device, with wheeled heel supports that allows the CPM to be used in a sitting position, as in riding along the floor, or with limited control by the patient while sitting in a bed. 
   Yet another objective of the present invention is to provide a track or rail system to isolate the movement of the wheels, such that the wheels can operate smoothly over any surface (i.e. rumpled bed sheets, thick carpet, or the like). 
   Still another embodiment of the instant invention provides an adjustable rigid, or semi-rigid, support means that is removably or permanently attached to the proximal sling module and distal sling modules to provide pressure to the upper portions of the patient&#39;s limb to cradle and hold the limb to achieve the maximum possible extension, similar to the manual techniques employed by physical therapists. 
   An additional objective of the invention is to provide a device which is light-weight and folds into a manageable package, that can be readily rolled along its own wheels. 
   Other objectives and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a right side view of the basic therapy device with the frame in the flex position; 
       FIG. 2  is a right side view of the same basic therapy device shown in  FIG. 1 ; 
       FIG. 3  is a front perspective view of the preferred embodiment of device in the flex position; 
       FIG. 4  is an front end view of the therapy device of  FIG. 3  in a flex position; 
       FIG. 5  is a left side view of the therapy device of  FIG. 3  with the frame in the flex position; 
       FIG. 6  is a left side view of the therapy device of  FIG. 3  with the frame in the extended position; 
       FIG. 7  is a left side perspective view of the therapy device with the frame in the flex position with longer upper support means on both the proximal and distal modules; 
       FIG. 8  is a left side view of the device of  FIG. 7  illustrating the therapy device in a sitting position; 
       FIG. 9  is a perspective view of the therapy device with a partial track; 
       FIG. 10  is a perspective of an alternative embodiment of the therapy device pivotally attached to a base; 
       FIG. 11  is a end view of the alternative embodiment of  FIG. 10 ; 
       FIG. 12  is a left side view of the alternative embodiment of  FIG. 10  with base in the flex position; 
       FIG. 13  is a left side view of the alternative embodiment of  FIG. 10  with base in the extended position; 
       FIG. 14  is an exploded perspective of the components of the modular frame of the embodiment in  FIG. 10 ; 
       FIG. 15  is a side view of the motor and worm gear of the therapy device; 
       FIG. 16  is a front view of one embodiment of a wireless module for controlling the any of the aforementioned embodiments. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Detailed embodiments of the instant invention are disclosed herein, however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific functional and structural details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. 
   Referring now  FIGS. 1 and 2  which shows a version illustrating the major components of the instant modular therapy frame device, or assembly, generally referred to as  10 .  FIG. 1  is right side view of a basic modular therapy device in the flexed position, wherein the modular frame assembly the can be either folded up or disassembled for easy transport and storage. The device  10  includes a proximal sling module  30 , a distal sling module  40 , a heel plate module  50  with wheel assembly comprising left and right wheels  53 ,  54  and an operating system  63  with a motor  64  ( FIG. 3 ) mounted to the distal sling module  40 , the motor  64  in communication with a controller  67 . 
     FIG. 2  is right side view of the same basic therapy device  10  shown in  FIG. 1 .  FIG. 2  illustrates a patient&#39;s limb  73  within the device  10 , in the extended position. 
   Preferably, the modular components  30 ,  40  of the frame are constructed of, albeit not limited to, a hollow rectangular box beams of lightweight materials, such as aluminum or thin gauge steel or plastic, which make it easy for the user to transport. In addition, other materials and shapes, having the requisite strength, rigidity and weight, may be utilized. 
   One example of a means for connecting the modules  30 ,  40  are illustrated in the exploded view in  FIG. 14 , which illustrates apertures formed along at least one of the ends the frame members which are constructed and arranged to cooperate with at least one pin  62  to form pivoting connections between modules  30 ,  40 . However, the means for connecting the may be attached by bolts and nuts, bolt and coddle pins or any other similar means of removable connection known in the art. 
   Referring now to  FIGS. 3–4 , which illustrate the various components of the preferred embodiment of the present invention. The embodiment shown in  FIG. 3-9 , is preferred as it is lighter and less cumbersome and may be used with the patient in the sitting position. The device  10  of this embodiment weights about 14 pounds and folds into a transportable package of about 12 inches by about 14 inches. 
   At the distal sling module  40 , a cross member  47  is attached at each end to two elongated rods  41 ,  42  which extend parallel along the distal portion of the patient&#39;s limb during flexing of the joint. At least one adjustable or permanent lower support means  43  extends between the two elongated rods  41 ,  42  to cradle the lower portion of the patient&#39;s limb as the two elongated rods  41 ,  42  pivot through a preselected range of motion. 
   The opposite ends of the elongated rods  41 ,  42  of the distal sling module  40  can be either pivotally connected to the lower end of elongated beams  31 ,  32  of the proximal sling module  30 , using any removable connection means  62 , shown here as, albeit not limited to, a removable pin ( FIGS. 5 ,  6 ). Otherwise, the elongated rods  41 ,  42  of the distal sling module  40  are pivotally connected to distal module extensions  75 , which telescope into the ends of the elongated beams  31 ,  32  of the proximal sling module  30 . 
   If the elongated rods  41 ,  42  of the distal sling module  40  are pivotally connected to distal module extensions  75 , then distal ends of the elongated beams  31 ,  32  of the proximal module  30  have at least one of aperture or detent  44   a  for cooperating with spring loaded buttons located on two extensions  75  connected to the distal sling module  40 . The two extensions  75  telescope into the ends of the elongated beams  31 ,  32  of the proximal sling module  30 . These cooperating fasteners permit the precise adjustment in length to virtually any limb, such as, knee to hip length. 
   Similarly, the distal ends of the elongated rods  41 ,  42  of the distal module  40  have a series of apertures or detents  44   b  for cooperating with spring loaded buttons on the heel plate module  50 . The heel plate module  50  has two extensions  51  which telescope into the ends of the rods  41 ,  42  of the distal sling module  40 . These cooperating fasteners permit the adjustment in length to fit limbs of different height, for example, the length from knee to foot. 
   The proximal sling module  30  and/or a distal sling module  40  can each include at least one adjustable upper support means. Although not limited to, the embodiments of  FIG. 3-9 , illustrate two separate support means  36 ,  37 ,  48 ,  49  to provide pressure to the upper portions of the patient&#39;s limb to achieve the maximum possible extension, similar to the manual techniques employed by most physical therapists. 
   The adjustable upper support means  36 ,  37 ,  48 ,  49  can be removably or permanently attached to the proximal sling module  30  and/or distal sling module  40  by any means of attachment (not shown) known in the art, i.e., adhesives, rivets, or the like. 
   Moreover, the removable, adjustable upper support members  36 ,  37 ,  48 ,  49  can be any made into any length along the longitudinal axis of the elongated beams  31 ,  32  and/or elongated rods  41 ,  42 . This is advantageous since after most post-operative situations, more pressure along the upper portion of proximal and/or distal portion of the patient&#39;s limb is desired. Thus, a longer upper support member  36 ,  37 ,  48 ,  49  is needed, as shown in  FIG. 7 . However, during the physician prescribed period of use of the instant CPM device, the longer upper support member  36 ,  37 ,  48 ,  49  can be removed and replaced with thinner upper support members, that will provide less pressure along the upper portion of the patient&#39;s limb. 
   The upper support means  36 ,  37 ,  45 ,  46 ,  48 ,  49  can be constructed of a rigid, semi-rigid material or a composite, for example, aluminum, thin gauge steel or plastic. In addition, other materials and shapes, having the requisite strength, rigidity and weight, may be utilized, (i.e. leather, nylon, or the like). In CPM, the patient exerts no active resistance to the movement of the patient&#39;s limb nor is there any positive muscular contractions. The lower support material  43 ,  45  must be constructed from a material strong enough to carry the weight of the patient&#39;s limb, for example, flexible cloth, film or relatively stiff sheet. 
   Additionally, the adjustable upper and/or lower support means  36 ,  37 ,  43 ,  45 ,  48 ,  49  can include an inner lining, or padding, which is in direct contact with the patient and will provide additional comfort and protect the patient&#39;s limb from irritation and/or chaffing during CPM movement. 
     FIG. 5  is left side view of the modular therapy device  10  of  FIGS. 3–4  in the flexed position, wherein the modular frame assembly is in the process of being folded for easy transport and storage. 
     FIG. 6  is left side view of the same therapy device  10  shown in  FIGS. 3–4  in the extended position. 
     FIG. 8 . is left side view of the modular therapy device  10  of  FIGS. 3–4  in with the wheel assembly  53 ,  54  in contact with the floor surface, for a patient in a sitting position. 
   In the less preferred embodiment depicted in  FIGS. 10–16 , wherein like elements are number consistently throughout, the device  10  includes a proximal sling module  30 , a distal sling module  40 , a base module  20  with an adjustable link  79 , a heel plate module  50  and an operating system, i.e. power assist system, comprising at least a motor  64  and controller  67 . 
   The base module  20  serves to support the device  10  on a surface such as a floor, table, or bed. The base  20  has an elongated shape constructed and arranged for being placed horizontally on a surface. In one preferred embodiment of the base  20 , the proximal portion  82  of the base  20  includes arms  22 ,  23  that are pivotally connected to the proximal sling module  30  via any connection means known in the art, i.e. pin  90 . Like the previous embodiment, the proximal sling module  30  supports the patient&#39;s thigh or upper arm during operation of the device  10 . The distal portion  24  of the base  20  can include lateral extensions  25  to increase stability. 
   Though not shown in  FIG. 10 , the extensions  25  may be completely removed from the distal portion  24 . Moreover, the extensions  25  are laterally adjustable via retainers  26  to secure the extensions in a selected position. The retainers  26  may be spring biased protrusions in the distal portion  24  cooperating with apertures  26  in the extensions or a series of apertures in both the extensions and the bottom through which pins may be inserted (not shown). 
   As illustrated in the exploded view of  FIG. 14 , the base  20  includes a shaft portion  80  which joins the proximal  82  and distal  24  ends of the base  20 . In one embodiment, the shaft  80  of the base  20  is bifurcated into legs  27 ,  28  connecting the distal end  24  to the arms  22 ,  23 . The legs  27 ,  28  of the shaft  80  have a series of apertures  29  for selective pivoting connection of the adjustable link  79 . 
   The distal sling module  40  is connected to the base  20  by via the adjustable link  79  which is variable in length by telescoping components  32 ,  33  selectively positionable by retainers  34  similar to those on extensions  25 . Preferably, the adjustable link  79  is centered between the legs  27 ,  28  and pivotably connected to the base  20  by a pin  84  extending through both legs  27 ,  28  and the end of the pin  84 . The other end of the link  79  is pivotably connected to the distal sling module  40  by another pin  35  extending through bracket  86  connected to cross member  47 , shown in  FIGS. 12–13 . 
   Similar to the previous embodiment of  FIGS. 3–8 , the cross member  47  of  FIGS. 10–14  is attached at each end to two elongated rods  41 ,  42  which extend parallel along the distal portion of a patient&#39;s limb during flexing of the joint. A support material  43  extends between the two elongated rods  41 ,  42  to carry the limb as the elongated rods pivot through a preselected range of motion. The material  43  may be flexible cloth, film, or a relatively stiff sheet. 
   As illustrated in  FIG. 14 , the distal ends of the elongated rods  41 ,  42  have a series of apertures or detents  44   b  for cooperating with spring loaded buttons on the heel plate module  50 . The heel plate module  50  has two extensions  51  which telescope into the ends of the rods  41 ,  42  of the distal sling module. These cooperating fasteners permit the adjustment in length to fit limbs of different height. 
   The opposite ends of the elongated rods  41 ,  42  of the distal sling module  40  are pivotally connected to the lower end of elongated beams  31 ,  32  using removable any removable connection means  62 , shown here as, albeit not limited to, a removable pin ( FIG. 14 ). Otherwise, the elongated rods  41 ,  42  of the distal sling module  40  are pivotally connected to distal module extensions  75 , which telescope into the ends of the elongated beams  31 ,  32  of the proximal sling module  30 . 
   The patient&#39;s joint to be flexed will be situated adjacent this pivotal connection means  62  with the proximal portion of the limb supported by the proximal sling module  30 . Elongated beams  31 ,  32  extends along each side of the patient&#39;s limb with a lower support material  45  between the elongated beams  31 ,  32  supporting the proximal portion of the limb. 
   If the elongated rods  41 ,  42  of the distal sling module  40  are pivotally connected to distal module extensions  75 , then the distal ends of the elongated beams  31 ,  32  have a series of apertures or detents  44   a  for cooperating with spring loaded buttons on the distal module extensions  75 , as they telescope into the ends of the elongated beams  31 ,  32 . These cooperating fasteners permit the precise adjustment in length to virtually any limb, such as, knee to hip length. 
   Similarly, the distal ends of the elongated rods  41 ,  42  have a series of apertures or detents  44   b  for cooperating with spring loaded buttons on the heel plate module  50 . The heel plate module  50  has two extensions  51  which telescope into the ends of the rods  41 ,  42  of the distal sling module. These cooperating fasteners permit the adjustment in length to fit limbs of different height, for example, the length from knee to foot. 
   Although not shown in  FIG. 10-14 , the proximal sling module  30  and/or a distal sling module  40  can each include an adjustable upper support means  36 ,  37 ,  48 ,  49  to provide pressure to the upper portions of the patient&#39;s limb. The adjustable upper support means  36 ,  37 ,  48 ,  49  can be removably or permanently attached to the proximal sling module  30  and/or distal sling module  40  by any means of attachment (not shown) known in the art, i.e., adhesives, rivets, or the like. 
   Moreover, the removable, adjustable upper support members  36 ,  37 ,  48 ,  49  can be any constructed into any length along the longitudinal axis of the elongated beams  31 ,  32  and/or elongated rods  41 ,  42 . 
   The upper support means  36 ,  37 ,  45 ,  46 ,  48 ,  49  can be constructed of a rigid, semi-rigid material or a composite, for example, aluminum, thin gauge steel or plastic. In addition, other materials and shapes, having the requisite strength, rigidity and weight, may be utilized, (i.e. leather, nylon, or the like). The lower support material  43 ,  45  must be constructed from a material strong enough to carry the weight of the patient&#39;s limb, for example, flexible cloth, film or relatively stiff sheet. 
   Additionally, the adjustable upper and/or lower support means  36 ,  37 ,  43 ,  45 ,  48 ,  49  can include an inner lining, or padding, that will provide comfort and protect the patient&#39;s limb from irritation or chaffing during movement. 
   As illustrated in  FIG. 15 , the operating system, or, power assist device can include, albeit not limited to, a low powered (i.e. about 10 to about 20 VDC), hi-torque linear actuator  63 , having a motor  64  mounted to the upper end of the distal sling module rod  42 . The linear actuator  63  comprises a motor output shaft  65  and a complementary power transfer part, shown here as, albeit not limited to, a circular, or worm, gear  66  fixed by the pin  62  to elongated beam  31  as shown in  FIG. 14 . The linear actuator  63  can comprise any means for providing power, for example, stepper motor or the like. 
   An optical or mechanical encoder (not shown) may be used for the precise control of the linear actuator  63 . The rotation of the output shaft  65  causes the circular gear  66  to turn which moves the distal sling module  40  relative to the proximal sling module  30 . The motor  64  is operatively connected through either elongated rods  41 ,  42  with the controller  67 . 
   The controller  67  can be as simple as an off/on switch or include a programmable system which can include a speed control means for the motor  64 . Such other features which may be included into the controller  67  include, a timer for session duration, repetitions over time, and length of throw of the worm gear  66  controlling angle of flex. Also, a safety circuit may produce a signal, (i.e. audio or visual or both), if there is an extension beyond the programmed parameters. 
   Additionally, the controller  67  and/or linear actuator  63  may be powered by any means for supplying power known to the skilled artisan. For example, the controller  67  and/or linear actuator  63  may include a battery pack (not shown) and be connected to the motor  63  through interior portion of either elongated rods  41 ,  42  or preferably by a wireless remote  68 , (i.e. RF, IR, etc.), shown in  FIG. 16 . 
   The wireless remote  68  is preferred to obviate the possibility of entangling the operating system with the bed clothes or any moving parts of the device  10 . A wireless receptor (not shown) may be on the controller  67  or directly on the motor  64 . Although not limit to, the controller  67  is mounted on the heel plate module  50  in  FIGS. 1–14 . 
   Preferable, the heel plate module  50  has a flange  88  for supporting the extremity of the patient&#39;s limb to assist in the proper location of the patient&#39;s limb in the device. The flange  88  is mounted on an axle  52  intermediate a set of wheels  53 ,  54 , one at each end of the axle  52 . The extension  51  is mounted near each wheel  53 ,  54  normal to the axle  52 . As previously discussed above, the ends of the extensions  51  are adjustably telescoped into the ends of the elongated rods  41 ,  42  of the distal sling module  40 . Thus, the heel plate  50  and the distal sling module  40  may be further adjusted to comfortably conform to the length of the patient&#39;s limb. 
   To perform CPM on a patient&#39;s knee, for example, the patient is supine and the patient&#39;s leg is placed on the device  10  so that the thigh supported by the proximal lower support mean  45  and the calf supported by the distal lower support means  43  with the knee adjacent the pivot point between the distal sling module  40  and the proximal sling module  30 , as shown in  FIG. 2 . The proximal sling module  30  is then strapped to the patient&#39;s limb with appropriately sized proximal upper support means  36 ,  37 . The distal sling module  40  is fastened about the calf with distal upper support means  48 ,  49 . In this position, the wheels  53 ,  54  are in contact with a supporting surface, such as the floor, so that the wheels move across the surface in response to the actuation of the linear actuator  63  ( FIG. 8 ). The articulation of this embodiment is similar to that shown in  FIGS. 3 ,  4  of the first embodiment and  FIGS. 12 ,  13  of the second embodiment. 
   Next, the controller  67  is programed, as desired, and the motor  64  is energized. As the linear actuator  63  moves the proximal sling module  40  relative to the distal sling module  30 , the patient&#39;s leg can achieve a full range of motion, for example, albeit not limited to, about −30 degrees to about +155 degrees. 
   In addition, a track or rail system can be included on either of aforementioned embodiments of the instant device to provide unobstructed movement of the wheels  53 ,  54 , either across the floor or across other surfaces, such as rumpled sheets on a bed, ( FIG. 9 ). In one preferred embodiment, the track is formed as a C-shaped channel  71 ,  72  enclosing each wheel. The tracks  71 ,  72  may or may not be joined by cross ties (not shown) and the tracks  71 ,  72  may or may not be flexible. The length of the tracks  71 ,  72  is commensurate with the distance the wheels  53 ,  54  move in response to the operation of the linear actuator  63 . 
   It is to be understood that while a certain form of the invention is illustrated, it is not to be limited to the specific form or arrangement herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown and described in the specification and drawings/figures. 
   One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. The embodiments, methods, procedures and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the invention and are defined by the scope of the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art are intended to be within the scope of the following claims.

Technology Category: 1