The present invention subject matter relates to a device and method for lifting a patient in a first position in one location, transporting the patient to a second location, and depositing the patient at the second location in a desired position.
A patient lift and transfer device is commonly known as a device that transports a patient who is in a first position at a first support. The patient may, for example, be in a supine position on a bed. The patient may be moved to a second support and positioned in a selected position which may be the same or different from the first position by such a patient lift and transfer device. For example, the patient may be moved to a wheelchair and deposited on the wheelchair in a sitting position. Commonly, the device is movable on wheels from a first location adjacent to the first support to a second location adjacent to the second support.
Typically, a number of operations must be performed to effect such a transfer, especially since the patient is often unable to assist the attendant or attendants performing the transfer. For example, in moving a patient from a bed to a wheelchair, the lift and transfer device typically must be moved to a position to interact with the patient on the bed. Support means must be interposed between the patient and the bed so that the patient can be lifted by the support means. The patient is then lifted from the bed so as to be movable free of engagement with the bed or any bed frame. The device is next wheeled to a position adjacent to the wheelchair. The patient must be lifted to a position above the wheel chair and lowered into it. The device must be formed to permit movement of the patient into engagement with the wheelchair without being blocked by elements of the wheelchair. Prior to this operation, the patient must be moved from the supine position to the sitting position. Once the patient is lowered into the wheelchair, the portions of the device between the patient and the wheelchair must be removed without undue discomfort to the patient.
In many common prior art embodiments, the above-described operations require the services of two attendants, and may require as many as eight minutes for their performance. In the context of hospitals and nursing homes, it is very important to reduce labor requirements wherever possible. Facilities face significant budget constraints. The current levels of staffing for a ward or a facility give each nurse or other attending staff member only so many minutes per patient per shift. Accordingly, reducing the labor effort required for patient transfer would be expected to enable a higher level of patient service for a given budget.
In the case of home health care, a patient might have only a single aide on duty. Performing a transfer that requires two attendants requires making special arrangements with a care provider agency to provide a second aide to accomplish the transfer. The requirement for a second aide can mean the difference for a patient between being able to be home and having to be institutionalized. Accordingly, it is highly desirable to provide a lift and transfer device that can be reasonably operated by a single person.
The well being and longevity in service of health care personnel is adversely affected by these difficulties in the physical handling of patients. According to a United States Department of Defense Study, nursing is a high-risk occupation, second only to heavy industry, because the high volume of lifting patients every day leads to fatigue, muscle strain, and injury. The study states that 12% of nurses leave the profession each year due to chronic or acute back injuries and pain. According to nursing literature, there is no ergonomically safe way to lift patients. The weight of an adult patient exceeds tolerance limits set by the NIOSH (National Institute for Occupational Safety and Health) for compressive forces to the lumbar spine. Accordingly, devices that provide for ease of patient handling, particularly when only one attendant is available, can increase the quality and availability of nursing service by helping to reduce the number of experienced health care providers who need to leave the profession.
Other significant concerns in lifting and transferring patients are the comfort and security of the patient. In order to lift a patient, many prior art devices use different types of slings which are each supported on a lift. A body sling is used to support a patient's entire body. The sling is lifted and moved to transport the patient. However, the use of such body slings has many common downsides. For example, even when the body sling has more than one support point, the sling may tend to rock. Rocking causes a feeling of insecurity to the patient. Further, it is difficult to center the patient in a sling so that the patient's body will not slide along the surface of the sling to reach a position of equilibrium. Many patients have fragile skin, and even the limited abrasion caused by normal sling materials and minimal patient sliding can cause skin tears.
Another currently available sling is an elongated, wide strip anchored at a first end to a lift support point. The sling is brought under a first armpit of the patient, around the patient's back, below a second armpit and back to the front of the patient. A second end of the sling is fixed to the lift support point. During lifting, the sling applies a significant portion or all of the patient's weight to the patient's armpits. Accordingly, the sling can cut into the patient and cause great discomfort, which it is highly desirable to minimize. Further, this pressure to the underarms can impede blood flow and lead to undesirable effects. Such devices may also cause the patient emotional as well as physical discomfort since the patient may feel insecurity while suspended in midair.
Other previous devices for patient transfer provide a structure that will support the patient during the transfer process and through the lowering of the patient into the wheel chair or other second location. In prior art devices with back and buttocks support for the patient, reliable support is provided during the transfer process. However, once the patient is in the second location, the supports are still in place between the patient and the wheelchair. The patient must be leaned forward to allow removal of the back support. Other manipulation must be performed to remove the support from between the patient and the wheelchair seat. Each manipulation of the patient that must be performed may increase discomfort to the patient. Where the patient is fragile, each manipulation additionally presents a risk of injury. It is highly desirable, then, to provide a transfer device in which the amount of manipulation of a patient in a second location is minimized in order to remove the transfer device.
Prior art transfer devices are also not widely available for bariatric patients. Bariatrics is a branch of medicine specializing in the treatment of overweight and obesity. Many bariatric patients weigh 350 to 750 pounds. A number of nursing homes limit the weight of patients they will admit to 300 pounds. One reason for this is the difficulty in handling patients over 300 pounds. A transfer device adaptable to bariatric patients would enable a wider range of patients to be served and provide a competitive advantage to health care providers using them.
Accordingly, there remains a need in the art for an alternative device and method for patient lift and transfer that solves these problems. The present subject matter addresses this need.
In accordance with the present subject matter, a lift and transfer device is provided in which a single operator can transfer a patient from one location to another location with minimal patient manipulation while providing a high level of comfort and security to the patient. The device in one form includes a wheeled base which may be wheeled in a transverse direction under, for example, a bed to be positioned at a first location. A lift is supported at a side of the base to be transversely adjacent to the bed when substantially the remainder of the base is under the bed. A patient support assembly supported on the lift has first and second transversely extending support arms cantilevered from a longitudinally extending main support arm pivotally supported on the lift. The first support arm carries a back support section which supports a back and other parts of the body. The second support arm carries a leg support section which supports a patient under and behind the knees. The patient is supported while leaving the lower torso, buttocks and thighs substantially free.
In a first angular position, the main support arm supports the backrest so that a patient's weight is applied to the back support section in a substantially vertical direction. This position is suitable for lifting the patient from a bed. The main support arm is rotated to a second angular position and lifted so as to be positionable above, for example, a wheelchair in a second location. In the second angular position, the patient's back is more vertically than horizontally disposed. In this position, horizontal force can be applied to the sides of the patient. Where the horizontal force is applied in response to gravity, first and second pivot arms each have an upper end pivotally supported on the back support section and a lower end having a torso grip pad positioned adjacent one of the patient's sides. An elbow support, which may also include a forearm support, is provided along with each torso grip pad. The support provides for comfortable placement of the patient's arms and is arranged to bear weight but not enough to cause discomfort to a patient. Reaction of body weight against the back support section is shared by the back, rib cage and elbows and/or forearms. The leg support section shares body weight support.
As the patient is rotated to the more generally vertical position, the predominant reaction of the device to body weight transitions from the backrest to the torso grip pads. The angular orientation of the pivot arms enables a direct interaction of vertical and horizontal forces at the torso grip pads. The vertical body weight loads applied to the grip pads are directly countered by a horizontal reaction force from the patient's rib cage. These horizontal forces are sufficiently large that when coupled with friction they are capable of supporting substantial portions of body weight. The horizontal force applied to the patient varies as a function of both patient body weight and of angular displacement of a respective pivot arm from the vertical axis. The resultant forces applied to each of the patient's sides by the pivot arms are consequently self-adjusting.
A desired range of angular displacement is selected for each pivot arm with respect to a nominal range of patient dimensions. The normal force applied by each torso grip pad times the coefficient of friction is typically greater than approximately one half the body weight of the patient not otherwise supported. A vertical weight support means comprising means for providing a vertical reaction to forces vertically applied by the body of the patient may be used in conjunction with the pivot arms to provide for positive support in the case of bariatric and other applications.
The patient is raised to a height to be positionable above a wheelchair in a second location and lowered into the wheelchair. In an alternative form, the lift and transfer device may comprise a lift which is supported to a bed frame structure, i.e. connected directly to the frame structure or coupled by an intermediate member. In another alternative form, the lift may be an overhead lift. In these embodiments, the transfer means are rotated in a horizontal degree of freedom from one location to a next rather than being wheeled.
Since there is not a support structure below the patient's buttocks, no manipulation must be done to the patient to allow seating in the wheelchair or in another second location. The pivot arms may be swung away from the patient's body, and the device may be wheeled transversely to remove the backrest and knee support from engagement with the patient. Minimal manipulation of the patient's arms is required.
Further, the methods contemplated herein comprise moving the patient from a first location to a second location and applying horizontal force to the patient's torso as a function of the verticality of the patient's spatial disposition when moving the patient from a first position to a second position.
Embodiments of the invention are described with reference to the following drawings.
In the present embodiment, the transport section 10 comprises a wheeled platform 20. The platform 20 includes substantially parallel legs 21 and 23 extending transversely from opposite ends of a longitudinally disposed leg 22. The transverse and longitudinal designations are arbitrary; they serve to describe relative spatial relationships within the lift and transfer device 1. Wheels 26 and 27 are mounted beneath a distal end of the leg 21 and a proximal end of the leg 21 respectively. In the present description, proximal refers to a location adjoining the leg 22. Wheels 28 and 29 are mounted beneath a proximal end and a distal end of the leg 23 respectively. The wheels 26-29 are mounted on swivel mounts to facilitate ease in directing the device 1. The wheels 27 and 28 are preferably provided with conventional wheel locks 32 and 33 respectively to permit fixing the device 1 at a location. A preferred construction for the platform 20 is welded tubular stock. This form of platform 20 is both stiff and lightweight.
The platform 20 in one nominal embodiment has a height of four inches. The platform 20 is easily slidable under a hospital bed so that the patient handling section 14 may be conveniently placed over the bed. The legs 21 and 23 are spaced in the longitudinal dimension so that they may surround a wheelchair. The legs 21, 22, and 23 form a U, with the open top of the U extending in the longitudinal direction. Consequently, the patient handling section 14 may be moved conveniently to and from a location over a wheelchair from the side of the wheelchair. A handle 38 fixed to a top of the lift section 12 may be used to transmit manually applied motive force to the device 1. The legs 21, 22 and 23 define a rectangle 36. The components further described below are dimensioned so that the center of gravity of the device 1 with or without the patient 2 carried therein is placed substantially near a center of the rectangle 36 to provide for stability.
The lift section 12 comprises a well-known electrically driven lift 40 mounted to the leg 22. The lift 40 comprises a fixed column 42 mounted to the leg 22. The fixed column 42 includes conventional gearing and an electric motor to raise and lower a sliding linear column 44 mounted over the fixed column 42. The lift 40 is powered by a 24 volt battery/charging system 46 mounted to the leg 22 adjacent to the lift 40. A control switch 50 is mounted to the top of the lift 40. The control switch 50 is operable in a conventional, well-known manner to operate the lift 40 in a raise, lower or off mode.
The patient handling section 14 comprises a main support arm 60 extending in the longitudinal direction. The main support arm 60 rotates on a support shaft 62 journaled in a clutch 64. The clutch 64 is mounted at a top of the lift 40. A clutch control lever 66 is operable in a first position to lock the clutch 64 and prevent rotation of the support shaft 62 and in a second position to permit rotation of the support shaft 62. Alternatively, the clutch 64 could be replaced by a friction drag. A friction drag provides for ease in rotation of the support shaft 62 while securing the support shaft 62 in an angular position when a force is not applied by an operator to the main support arm 60. The main support arm 60 may be disposed in a first position or a second position corresponding respectively to first and second positions of the patient 2.
The main support arm 60 may be straight. Alternatively, it may comprise bends for selecting a relative position of the back support section 16 with respect to the leg support section 18. The system is dimensioned so that the vertical location of the support shaft 62 approximates that of the center of gravity of the patient handling section 14 including a patient 2. Thus, the main support arm 60 may rotate about a horizontal axis 63 extending through a space occupied by a patient when in the device (a “patient position”). Otherwise stated, the main support arm 60 is pivoted about a balance point in spatial registration with an expected center of gravity of a patient and pivoted elements of said device. Since the patient 2 is substantially balanced, an operator may tilt the main support arm 60 with a limited amount of effort. No motor is needed to rotate the main support arm 60, and construction is simplified. However, while a balance point may be selected that will conveniently accommodate a wide range of patients, bariatric patients may have weight distributed such that an operator may have difficulty rotating the main support arm 60. Also, variation in the location of the center of gravity of a bariatric patient may create force moments beyond the restraining capacity of the friction drag. For such situations, the clutch 64 or friction drag may be replaced by a motor to provide for powered rotation. An embodiment including a motor is illustrated in
The back support section 16 is further described with respect to
Such means for applying horizontal force to the patient 2 comprise first and second torso grip pads 74 and 76. The first and second torso grip pads 74 and 76 engage a proximal side and a distal side of the patient 2 (
Another alternative to having torso grip pads 74 and 76 mounted to pivot arms is the use of wedge members that bear against the sides of a patient 2. The wedge members can each be mounted to an adjustable support, and an attendant can manually set the position of each wedge against the sides of the patient 2. This alternative will apply horizontal force the patient 2 when the patient 2 is in either the first position or the second position. In contrast, the embodiment including pivot arms will primarily apply horizontal force only when the patient 2 is in the second position.
The first and second torso grip pads 74 and 76 are curved with an anatomical contour approximating a patient torso shape for greater surface area of contact than a flat pad. The first and second torso grip pads 74 and 76 are padded to permit deformation to conform to a patient's contour, providing for uniform load distribution and for greater comfort. Second ends of the pivot arms 79 and 81 are mounted to pivot supports 83 and 85 respectively.
The first torso grip pad 74 has extending from an outside surface (away from the patient 2) thereof a first support block 87. The first support block 87 is pivotally mounted on a first longitudinal arm 88 extending from the first end of the pivot arm 79. Similarly, the second torso grip pad 76 has extending from an outside surface thereof a second support block 91. The second support block 91 is pivotally mounted on a second longitudinal arm 92 extending from the first end of the pivot arm 81. The first and second support blocks 87 and 91 are preferably unitary with the first and second torso grip pads 74 and 76 respectively. The first and second torso grip pads 74 and 76 are consequently self-adjusting to engage sides of the patient 2. The first and second torso grip pads 74 and 76 impart a large and balanced force against the sides of the patient 2. As further explained with respect to
In the present example, pivot supports 83 and 85 are mounted to the back support arm 70. Many different arrangements may be provided for location of the pivot supports 83 and 85 and for the shape of the pivot arms 79 and 81. The pivot arms 79 and 81 are pivoted so that the first and second torso grip pads 74 and 76 provide compressive force against the torso of the patient 2. In the present embodiment, the pivot supports 83 and 85 are located so that the arcs of the pivot arms 79 and 81 intersect. In order to avoid interference, the pivot arms 79 and 81 are pivoted at a location behind the backrest 72 and extend to a position in front of the backrest 72. “Behind” and “in front of” are used here with reference to a direction in which the patient 2 will be facing when engaged in the device 1. The pivot arms 79 and 81 extend in both the longitudinal and transverse degrees of freedom. The pivot arms 79 and 81 are curved to extend around the backrest 72. The pivot arm 81 is located to be fully rotatable around the pivot support 83 free of engagement with the pivot arm 79. Therefore the distal side of the patient 2 can be completely cleared. Once the pivot arm 81 is swung away from the patient 2, the pivot arm 79 can be swung. Alternatively, the pivot supports 83 and 85 could be located next to each other at the back of the backrest 72, and the pivot arms 79 and 81 could swing in independent arcs. However, this would allow for a smaller angle between a vertical axis and a line from a pivot support 83 or 85 to a torso grip pad 74 or 76. Significance of this angle is described with respect to
In the above example, only the lift 40 has been illustrated as being motorized. In a wide range of applications, operators employing the lift and transfer device 1 may not desire powered movement of components other than the lift 40. However, power articulation may be utilized wherever desired. For example, the clutch 64 could be replaced by a motor drive to rotate the main support arm 60. Selected ones of the wheels 26-29 may be powered. Motor assist or hydraulic cylinder assist could be used in rotating the first and second pivot arms 79 and 81. The device 1 as illustrated is adapted to approach a hospital bed from the patient 2's right side. The device 1 could be constructed to approach a bed from the patient 2's left side by having the leg 22 extend over the wheels 26 and 29 rather than the wheels 27 and 28 (
First and second arm support units 94 and 96 are supported on the pivot arms 79 and 81 respectively. In the present embodiment, they are supported on the pivot arms 79 and 81 by being supported on lower ends of the first and second torso support blocks 87 and 91, respectively. The first and second arm support units 94 and 96 may also be unitary with the first and second torso grip pads 74 and 76, respectively. The first and second arm support units 84 and 96 may be made vertically adjustable with respect to the pivot arms 79 and 81, respectively. In another form, arm support units may be supported directly to pivot arms, for example, as in the embodiment of
The first arm support unit 94 includes an elbow support 97 supported on the first support block 87 and has a first forearm support 98 extending from the elbow support 97 and canted upwardly. Similarly, the second arm support unit 96 may include an elbow support 99 supported on the second support block 91. A second forearm support 100 may extend from the elbow support 99 and be canted upwardly therefrom. While pointed portions of the elbows may bear weight directly, it is desirable to provide cushioned support to the patient 2 in the elbow region to resist the force of gravity. The elbow region for purposes of the present description is an area near the elbow and toward the hand. The elbow region may be centered three or four inches from the elbow. This support facilitates application of force to be transmitted through bones of a patient 2 so that the shoulders help carry weight. Force is transmitted from the elbow region through the humerus (elbow-to-shoulder bone) to the shoulders.
The forearm supports 98 and 100 are pivotally mounted about the longitudinal arms 88 and 92, respectively. Therefore, it is preferable to make a centroid of area of the first forearm support 98 substantially collinear with the first longitudinal arm 88. Similarly, a centroid of area of the second forearm support 100 is collinear with the second longitudinal arm 92. The collinear placement prevents exertion of a force moment on the first and second torso grip pads 74 and 76 from the first and second forearm supports 98 and 100. There may be embodiments in which the forearm supports 98 or 100 may be mounted directly to the first or second longitudinal arms 88 or 92 respectively. It is not necessary for the first and second forearm supports 98 or 100 to be unitary with the first or second torso grip pads 74 or 76.
In preferred examples of the present embodiment, the arm support units 94 and 96 may together carry thirty percent of upper body weight. The potential for patient discomfort is therefore minimized. Since no strap, for example a prior art sling, is constricting a body part, the potential for impeding blood flow is also minimized.
F=(weight)tan θ
where weight is the amount of the patient's weight supported by the given torso grip pad 74 or 76. The value of the tangent of θ increases with the value of θ. By choosing to position the pivot supports 83 and 85 transversely away from their corresponding torso grip pads 74 and 76, the value of θ is increased. This difference in relative transverse positions can be varied when designing the back support section 16 to provide a compressive force on the patient 2 which is sufficient to support the patient 2 with a feeling of security and yet not sufficient to cause discomfort in a patient who is not unusually fragile. In this arrangement, reaction of body weight against the lift device 1 is shared by the back, rib cage and forearms in the vicinity of the elbow and by the knees.
As the patient 2 is rotated to a more generally vertical position, the vertical component of force applied by the backrest 72 decreases. The vertical force applied by the patient's body at the interface of the patient's torso 110 and each torso grip pad 74 and 76 increases. Due to friction between each of the torso grip pads 74 and 76 and the patient 2 and/or the patient's clothing, there is effectively a contact point between the patient 2 and each torso grip pad 74 and 76. At this contact point, there is an interaction of vertical and horizontal forces. The normal, or horizontal, force applied by each torso grip pad 74 or 76 times the coefficient of friction is greater than approximately one half the body weight of the patient 2 not otherwise supported. The horizontal force applied to the patient 2 varies as a function of patient body weight and an angular displacement of a respective pivot arm 79 or 81 from the vertical axis. The resultant forces applied to each of the patient's sides by the first and second pivot arms 79 and 81 are consequently self-adjusting. A desired range of angular displacement is selected for each pivot arm 79 and 81 with respect to a nominal range of patient dimensions. While a wide range of patients 2 will encounter no discomfort or ill effect due to the compression of the torso 110 by the pivot arms 79 and 81, it may be undesirable to position particularly brittle patients 2 in the back support section 16.
A single location of the leg support section 18 on the main support arm 60 in relation to the back support section 16 will accommodate patients over a range of heights. Taller patients will bend their legs at a greater angle with respect to their torsos than will shorter patients. Further forms of the main support arm 60 useful in accommodating a wider range of patient sizes are described with respect to
The first and second torso grip pads 74 and 76 in contact with the torso 110 are illustrated in
The patient handling section 14 including the patient 2 is rotated about the support shaft 62 to the second position as illustrated in
After the patient 2 is seated, the pivot arm 81 is swung away from the patient 2. The pivot arm 79 may then be swung without hitting the pivot arm 81. A minor amount of movement of an arm of the patient 2 is required to allow disengagement of the first torso grip pad 74. The lift and transfer device 1 may be moved transversely from the wheelchair 200. As noted above with respect to
Reference to the wheelchair 200 may be used to define spatial relationships of components in the lift and transfer device 1. A wide range of wheelchairs will have similar dimensions. Therefore, one set of dimensions within the patient handling section 14 and platform 20 may be selected to interact with many different wheelchairs. As seen in
The main support arm 60 is supported on a pivoted arm 260 which includes a pivot mount 261 about which the main support arm 60 pivots. The pivot mount 261 comprises a motor 262 that drives the main support arm 60 for rotation. The motor 262 may be electric but could take other forms, e.g. a hydraulic motor. The motor 262 can provide rotational power to assist in movement of a bariatric patient. The pivoted arm 260 also includes a main support arm stabilizing means 264 to maintain the main support arm 60 in a selected angular position. The main support arm stabilizing means 264 could comprise a friction drag, detent lock or other well-known means. The pivoted arm 260 is in turn pivoted around a rotatable arm 266, which in turn is supported on a vertical arm 270 fixed to the lift 40. In this embodiment, the selection of a second location is limited to an area adjacent to the bed frame 240 in an area in which the force moment applied from the center of gravity of the patient handling section 14 will result in force supported by the outrigger support leg 250 and not result in instability. The embodiment can be conveniently configured so that the position of center of rotation of the patient handling section 14 approximates that of the center of gravity of the patient handling section 14. Generally the center of rotation will be slightly above the center of gravity, providing for ease in rotating the patient 2.
In the embodiment of
A patient handling section 314 includes a main support arm 360 supported to a lower end of a liftable arm 300 by a roller assembly 304 having a lower end pivotally coupled to the liftable arm 300. An upper end of the liftable arm 300 comprises a coupler 306 which is supported by a standard overhead lift 342. The coupler 306 may be supported by the overhead lift 342 by a cable 344. In order to prevent swinging of the patient handling section 314 from the overhead lift 342, second and third cables 345 and 346 are also provided. As seen in
The roller assembly 304 comprises first, second and third rollers 308, 309 and 310 through which the main support arm 360 is moveable. For this purpose, the main support arm 360 may comprise a tube having a circular cross section, and the rollers 308, 309, and 310 may comprise pulleys each having a curved outer diameter essentially complementing the curvature of the main support arm 360. The third roller 310 is below the main support arm 360, and the first and second rollers 308 and 309 are mounted above. The main support arm is located at the center of a patient handling section 314 rather than at a side thereof. Rather than being rotatable around an axis as is the main support arm 60 (
The patient handling section 314 includes a back support section 316 supported on a first, rear end of the main support arm 360. A leg support section 318 is supported on a second, front end of the main support arm 360. The leg support section includes a leg rest 322. The back support section 316, as seen with respect to
The first torso grip pad 374 has extending from an outside surface (away from the patient 2) thereof a first support block 387. The first support block 387 is pivotally mounted on a first longitudinal arm 388 extending from the first end of the pivot arm 379. Similarly, the second torso grip pad 376 has extending from an outside surface thereof a second support block 391. The second support block 391 is pivotally mounted on a second longitudinal arm 392 extending from the first end of the pivot arm 381. The first and second support blocks 387 and 391 are preferably unitary with the first and second torso grip pads 374 and 376 respectively. The first and second torso grip pads 374 and 376 are consequently self-adjusting to engage the sides of the patient 2. The pivot arms 379 and 381 are disposed in front of the patient 2.
In this embodiment, the back support section 316 does not have a separate backrest. A first back support section 372 curves from the first torso grip pad 374 to define a back support for the proximal side of the patient 2. A second back support section 373 curves around from the second torso grip pad 376 to comprise a back support for the distal side of the patient 2. Reliable back support will be provided in the first and second positions (as defined above) even when the first and second back support sections 372 and 373 do not meet. First and second elbow supports 397 and 399 may be formed integrally with the first and second torso grip pads 374 and 376, respectively, between them and the pivot support arms 379 and 381, respectively.
The main support arm 360 may have a straight section 405 extending into the circle 361 to support the leg rest 322. The leg rest 322 is preferably at a position on or near the diameter of the circle 361. This construction is analogous to the location of the leg rest 22 in
In the embodiment of
In the embodiment of
In the embodiment of
The present subject matter being thus described, it will be apparent that the same may be modified or varied in many ways. Such modifications and variations are not to be regarded as a departure from the spirit and scope of the present subject matter, and all such modifications are intended to be included within the scope of the following claims.
This application claims priority to U.S. Provisional Patent Application Ser. No. 60/560,083 filed Apr. 6, 2004, the disclosure of which is incorporated herein by reference in its entirety.
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