Abstract:
Rehabilitation of an upper limb. The splint comprises: an arm ( 8 ) that is supported by a frame ( 10 ) consisting of at least one upper extension ( 20 ) that is provided at the end of a pivot ( 21 ) of a substantially vertical axis, an arch that is mounted on the pivot by means of a flexion-extensional drive motor ( 26 ) for the upper member, and an upper structure ( 31 ) that supports the anti-brachial and brachial segments and is comprised of a housing ( 34 ) that is adapted onto said arch, an abduction-adduction drive motor for the upper arm and an arm ( 40 ) that links said motor to the brachial segment. The invention can be used for passive motion splints.

Description:
BACKGROUND OF THE INVENTION 
     This application claims priority to French Application No. 99/01579 filed on Feb. 8, 1999, by the same inventors and having the same title as above, the entire contents of which is hereby incorporated by reference. 
     1. Field of the Invention 
     The present invention concerns articular and ligament rehabilitation of the upper limbs, and more particularly, the rehabilitation of such limbs by the passive motion method. 
     Such method consists of placing the upper limb in a splint that is comprised of articulated segments reproducing and giving effect to complex scapular-humeral articulation, as well as to the equally complex ulnar articulation. The design of these articulated segments is such as to allow the arm and forearm of the upper limb to be moved by means of variable speed motorized devices in specific angular ranges in the principal movements considered, effected independently or concomitantly, which movements are abduction-adduction, horizontal flexion-extension, internal-external rotation of the forearm, and even the pronation-supination of said forearm. 
     2. Description of the Related Art 
     Splints able to meet these requirements, taking into account the anatomical characteristics of the articulations of the upper limb, are well known and can be considered to meet the objectives. 
     In general, due to their functionality such splints are heavy, relatively bulky, and for some, can only be used with a right or left upper limb. 
     In practice up until the present, the implementation of such passive motion splints was generally done within a medical or paramedical environment, in specialized structures and by personnel specifically trained in that regard. 
     Advances made in servo technology, motorization control and adjustment devices adapted to said splints have opened a door to a different practice consisting of providing a patient with a passive motion rehabilitation splint along with an implementation protocol that the patient himself can adapt to. 
     Given the formulation of such a proposal, the question arises of making such a splint personally available to a patient, it being understood that, in any event, the use of such a splint is temporary. 
     This is the reason there has been a trend toward offering upper limb motion splints for rent, so that each patient concerned can have temporary access to the equipment he needs to follow the rehabilitation protocol appropriate to him. 
     Although such practice of making available a passive motion splint would seem to be satisfactory, in practice, it has two principal difficulties. 
     The first concerns the bulkiness and weight represented by such passive motion splints for an upper limb, a bulkiness and weight that generally hamper a flexible, fast and effective rental service that only requires a simple means of transport for the patient. 
     The second is that of having equipment that can meet rental needs that are difficult to foresee, for rehabilitation of either the right or left upper limb. 
     These two obstacles appear to be a serious hindrance to the development of the rental practice. 
     The object of the invention is precisely to overcome the problems posed by current passive rehabilitation equipment, by proposing a new upper limb rehabilitation splint that has relatively small overall dimensions, can be installed and used practically and quickly, and can be used in the rehabilitation of either a right or left arm, subject to adaptation adjustment. Such adaptation adjustment is most often left to personnel responsible for the first installation who can, from a single set of identical machines, meet all rental demands that could arise completely randomly. 
     SUMMARY OF THE INVENTION 
     In order to achieve the foregoing objectives, the splint for passive motion of an upper arm, of the type having an ante-brachial segment and a brachial segment that are relatively adjustable for flexion-extension and are adapted to a frame for support and motion in (independent and/or simultaneous) movements of horizontal flexion-extension of the upper limb, abduction-adduction of said limb, internal-external rotation of the forearm, and even pronation-supination, is characterized in that said frame comprises: 
     a substantially vertical arm held by a frame which is intended to be placed in relation to the back of an associated chair and which has at least one upper extension, provided at the end with a pivot that has a substantially vertical axis, known as horizontal flexion-extension of the upper limb and oriented toward the front of said seat, 
     an arch that is mounted on the pivot by means of a drive motor for the horizontal flexion-extension of the upper limb, 
     and an upper structure supporting the ante-brachial and brachial segments and having a housing adapted to the arch, a drive motor for abduction-adduction of the upper limb, mounted in the housing and an arm linking said motor to the brachial segment. 
    
    
     Various other characteristics will be seen from the description provided below, with reference to the attached drawings which show, by way of non-limiting examples, embodiments of the object of the invention. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an elevation of the splint according to the invention, in a first embodiment. 
     FIGS. 2,  3  and  4  are perspectives, corresponding to FIG.  1  and showing construction details in different scales. 
     FIG. 5 is a perspective, substantially similar to FIG. 2, but illustrating a variation of embodiment. 
     FIG. 6 is a top view diagram showing certain structural characteristics of the splint. 
     FIG. 7 is a perspective showing more precisely the structure of the splint. 
     FIGS. 8 and 9 are partial perspectives, in a larger scale, showing details of the construction. 
     FIG. 10 is a partial perspective, similar to FIG. 5, but illustrating a functional characteristic. 
     FIG. 11 is a partial perspective showing one variation of embodiment. 
     FIG. 12 is a side elevation, in larger scale, shown diagrammatically, substantially along plane XII—XII of FIG.  11 . 
     FIG. 13 is a partial perspective showing more clearly the construction according to FIG.  12 . 
     FIG. 14 is a partial diagram illustrating a functional characteristic of the means according to FIGS.  11  and  12 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Based on the example of embodiment illustrated in FIGS. 1 to  4 , the passive motion splint, according to the invention, has a frame  1  for support and motion, in independent and/or simultaneous movements, of an assembly  2  composed of an ante-brachial segment  3  and by a brachial segment  4  which are linked by an ulnar articulation  5  that can be immobilized in an adjustable angular position. In the illustrated example, segments  3  and  4  are immobilized in an orthogonal orientation in correspondence with the support of an upper left limb, by means of a trough  6  to hold the forearm and a trough  7  to hold the arm. 
     The frame  1  is composed of an arm  8  which has a column  9  held by a frame  10 , with which such column can be adjusted in either direction along the arrow f 1 , for example by a screw system  11 . 
     In the illustrated example, the frame  10  is an integral part of the base  12  of a chair  13  having a seat  14  and a back  15  intended to be occupied by a seated patient, whose upper left limb, in this instance, is to be given rehabilitation. 
     It should be considered, within the meaning of the invention, that the frame  10  could be raised from a base  16 , like the one illustrated in FIG. 5, such base being then independent of the seat  13 . 
     Within the principal objective of the invention is that of implementing means so that the frame  1  can be placed equally well in relation with the left side of the chair  13 , as illustrated in the drawings, or in relation with the right side, in such a way that, by the means subsequently described in relation to the purpose of the invention, the motion splint can perform its rehabilitation function equally well for the patient&#39;s right or left arm. 
     Within the scope of the variation according to FIG. 5, such means involve the design of the independent nature of the base  16 , which makes it possible to place the column  9  of the arm  8  to the left or right of the chair  13 . 
     In the embodiment in which the frame  10  is an integral part of the base  12 , one or more horizontal slide rails  17  are provided (as is diagrammed in FIGS. 1 to  4 ), on which a holder  18  that provides support for the column  9  by means of a shaft  19 , is mounted. 
     By the means described above, the arm  8  can be placed to the right or left, with respect to an anterior-posterior mean plane P of the chair  13  (FIG.  3 ). 
     The arm  8  has at least one upper extension  20  which, with respect to the frame  10 , is oriented toward the front of the associated chair  13 . The extension  20  defines, at the end, a pivot  21  that has an axis x-x′ that is substantially vertical and which can be placed in line with the right or left scapular-humeral articulation head for a patient occupying the chair  13 . 
     The arm  8  is preferably also provided with a lower extension  22 , which has the same characteristics as the extension  20 , so as to have a pivot  23  that is coaxial with the pivot  21  in order to ensure a single axis x-x′. 
     If applicable, the pivot  21  and the pivot  23  are reserved for mounting a substantially U-shaped arch  25 , which can be immobilized or driven in rotation by a horizontal flexion-extension motor  26  for the upper limb. 
     The motor  26  is designed, as is diagrammed in FIG. 6, in such a way as to be able to drive the angular motion of the arch  25 , whether the arm  8  is arranged in left or right lateral placement, or in the direction of the arrow f 2  within an angular range of 30°, or in the direction of f 3  within an angular range of 130°. 
     The arch  25  is composed of two arms  27  and  28  which, in a neutral position, extend parallel to the extensions  20  and  22  starting from the pivots  21  and  23 , and of a web  30  connecting said arms, which web is placed, in the same position of reference, substantially parallel to the column  9 . 
     The arch  25  carries the assembly  2  by means of a structure  31  occupying a position that is substantially higher on the web  30  below the arm  27 , so as to be able to be situated substantially in line with the right or left shoulder of a patient occupying the chair  13 . Such a vertical adjustment of the shoulder can be made by the means  11 , offering the possibility, as mentioned above, of moving the column  9  with respect to the frame  10 , according to the arrow f 1 . 
     The structure  31 , shown more clearly in FIGS. 5 and 7, comprises a support  32 , which is preferably made in the form of a bracket or a clevis oriented parallel to the arms  27  and  28 . The support  32  defines a substantially vertical pivoting axis y-y′ for a housing  34 , mounted on the support  32  by a pivot  33  and by an orientation means  35 , which is more clearly illustrated in FIG.  8 . Such means  35  have, for example, in the upper arm of the clevis or support  32 , a semicircular opening  35  centered on the pivoting axis y-y′, which receives and guides a locking button  36  carried by the housing  34 . The opening  35  covers an angular range on the order of 180°, so that it is possible, by moving the locking device  36 , to orient the housing  34  in one or the other of two stable positions, 180° from each other. 
     The housing  34  encloses a motor having an output shaft  37 , the axis of which is orthogonal to the axis y-y′ and which extends, in one or the other of the orientation positions of the housing  34 , always parallel to the arms  27  and  28  of the arch  25 . The output shaft  37  drives one, or preferably two, members  38  extending transversally to the plane of the arch and carrying a turn plate  39 , which provides the support for the assembly  2  by means of an arm  40 . The plate  39  is associated with turn adjustment means  41  for the arm  40 . These means  41 , as illustrated in FIG. 9, have a mechanism plate  42  mounted on an axis of rotation  43  presented by the plate  39  and having a semicircular opening  44  to accept an attachment and adjustment device  45 , for example carried by the plate  39 . The opening  44  covers an angular range of 180°, in such a way that it becomes possible to adjust the orientation of the arm  40  by turning it in one or the other of two positions, for example the first being the position illustrated in FIG. 9, and the second illustrated in the same figure by the broken line, the necessity for these two positions being explained as follows. 
     The arm  40  is comprised of a semi-arm  46 , called posterior, forming one piece with the mechanism plate  42 , and a semi-arm  47 , called anterior, which carries the brachial segment  4  of the assembly  2 . The semi-arms  46  and  47  are associated by a coupling  48 , which is combined with a bearing  49  for the free rotation of the semi-arm  47  in the event of release of the coupling  48 . 
     The motor in the housing  34  is designed to be able to operate in reversible rotation, at variable speed, in an angular range capable of causing an adduction movement within a range of 20° and an abduction movement within a range of close to 150°. 
     The implementation of the motion splint described above is done as follows. 
     For example, when the passive motion of a left upper limb is concerned, the arm  8  is laced to the left of the chair  13 , as diagrammed in letter G of FIG. 6, by means of the frame  10 , behind the back  15  of the chair  13  and laterally thereto, so that the axis x-x′ corresponds substantially to the scapular-humeral articulation head of the upper left arm. 
     Next, the housing  34  is adjusted by the means  35  and  36 , so as to immobilize this housing in an orientation such that the members  38  are oriented and directed toward the left, as illustrated in FIGS. 1 to  5  and  7 . 
     The means  44  and  45  of the return plate  30  are used to orient the arm  40  in the opposite direction of that of the frame  10 , that is, toward the front of the chair  13 , so as to place the assembly  2  in a situation favorable to receiving and holding the forearm and the arm of the upper limb in the troughs  6  and  7 . 
     In such a position, it is possible to control a horizontal flexion-extension passive motion rehabilitation of the left upper arm by controlling the power to the motor  26  which moves the arch  25  in an angular range of 30° in the direction of the arrow f 2  and in a range of 130° in the direction of the arrow f 3 . 
     It is also possible to control a rehabilitational passive motion of the upper arm by adduction and abduction movements by controlling the proper and suitable sequential power supply to the abduction-adduction drive motor enclosed in the housing  34 . 
     It is obviously quite possible to provide the concomitant control of both movements by adopting speeds and amplitudes that are predetermined and programmable each time. 
     The examples of rehabilitation movements that have just been discussed take into account a position of the upper arm which is held and immobilized by the segments  3  and  4  that have, as a function of the ulnar articulation adjustment  5 , a relational position of substantially 90° flexion. 
     It is obvious that the movements above can be programmed, maintaining the upper limb in full extension, by first adjusting the ulnar articulation  5 . 
     Assuming that the motion splint is to be used for the rehabilitation of a right arm, it is sufficient to place the arm  8  in relation to the right position, as shown by letter D in FIG.  6 . This is done either directly by means of the base  16 , or by adjusting the holder  18  on the slide rail(s)  17 . 
     Next, the means  35  and  36  are implemented to control the change of orientation of the housing  34  on the axis y-y′, so as to orient the arm  40  toward the exterior of the right side of the chair  13 . Finally, the means  44  and  45  are controlled to cause the turning of the assembly  2  and to bring it back in the direction of the front of the chair  13 , in such a way that the splint then occupies the position, as illustrated in FIG. 10, in which the same movements as those described before can be individually or concomitantly controlled. 
     The object of the invention also includes means designated in the aggregate by the reference  50  and suitable for maintaining an internal-external rotational movement of the forearm or the upper limb, such rotational movement occurring concomitantly with the abduction-adduction movement maintained by the motor in the housing  34 . 
     FIGS. 11 and 12 show that the means  50  include a fork  51 , the position of which can be adjusted on a slide  52 , provided by the housing  34 . The fork  51  provides a point of attachment  53  which can be placed, depending on the adjustment of the slide  52 , either to coincide with the axis of the output shaft  37 , or vertically offset with respect to said output shaft, and more particularly, in descending vertical movement. The point of attachment  53  is intended for the attachment of the end of a cable  54  held by a guide sleeve  55 , in such a way that its opposite end can be adjustably attached to an arm  56  that forms one piece with the semi-arm  47 . 
     By providing for the release of the coupling  48 , the means  50 , as described above, make it possible to achieve the following results. 
     When the fork  51  is adjusted so that the point of attachment  53  coincides with the axis  37 , the angular movement of the members  35  has no effect on the useful length of the cable  54 . 
     However, if the adjustment of the fork  51  brings the point of attachment  53  to a position such as  53   a , illustrated in FIG. 12, then the angular displacement in either direction of the arrow f 1  of the members  35  results in a corresponding variation in the useful length of said cable, between the point of attachment and where it enters the cable guide sleeve  55 , so that this cable controls, by means of the arm  56 , the rotation in either of the directions of the arrow f 3  of the semi-arm  47 , as illustrated in FIGS. 12 and 14. Consequently, concomitant with the abduction-adduction movement, there is an external-internal rotational movement applied to the forearm of the upper limb when said limb is placed in a semi-flexed state. 
     When the prior adjustment of the assembly  2  places the segments  3  and  4  in alignment for an extension of the upper limb, then the adjustment, as considered in the foregoing, results in the creation of, simultaneous with the abduction-adduction movement, a supination-pronation movement that makes it possible to offer the additional possibility of passive motion that can be combined with a horizontal flexion-extension. 
     The invention has a valuable application in the area of passive motion splints that are reserved for rental services.