FR2720270A1 - Elasticated medical knee support - Google Patents

Abstract

The support consists of a tube (1) of an elasticated fabric with two side reinforcing members (4) situated symmetrically along it. Each side member comprises an upper and a lower section (5, 6), the ends of which are fitted into non-stretch sleeves (7, 8), while their neighbouring ends are joined to central links (9) by two pivots (10, 11). The sleeves are connected to straps (12a, 12b; 13a, 13b) which go around the top and bottom of the support and are adjustable. The inner ends of the reinforcing members' sections are cranked outwards slightly to accommodate the links, which are made from a lightweight alloy and are adaptable to the shape of the patient's leg.

Description

 The present invention relates to a medical knee brace of the type comprising lateral reinforcements, that is to say rigid parts which control or prohibit certain abnormal movements of the knee.

 It is located between the external prostheses, equipped with complex articulations, adjustable according to pre-established sectors to immobilize or partially release the knee joint and the articulated knee pads, simpler but whose immobilization efficiency is not always sufficient depending on the cases to be treated.

 In this field, a medical knee brace is known in particular comprising a flexible tube of elastic material and, on at least one side, two lateral stiffening uprights carried by the flexible tube and articulated one on the other about an axis. transverse, these two uprights being intended to extend respectively along the femur and the tibia of the wearer, the end of at least one of the lateral uprights adjacent to the articulation being arched in a direction substantially perpendicular to the axis of the joint, the uprights being respectively held in place by peripheral straps.

This kneepad has a number of drawbacks: a double tourniquet effect determined by the straps
located respectively above and below the
knee in case the patient performs a bad
setting a large and very uncomfortable constraint
exercising in the popliteal area as soon as the
flexion movement is accentuated, sometimes rapid wear of the joint due to
all efforts focused on a single
articulation axis.

 The present invention aims to remedy the aforementioned drawbacks by providing a particularly comfortable knee brace exerting excellent support whatever the angle of mobilization and in which the tourniquet effect is eliminated.

 According to the invention, the knee brace is of the type comprising a flexible and slightly flared compression tube, constituted by an elastic fabric, two lateral stiffening uprights arranged symmetrically along the tube, each upright being articulated and comprising upper and lower branches which are in the form of sections of flat strips and whose free ends are respectively housed in inextensible longitudinal sheaths integral with the upper and lower parts of the tube, and peripheral tightening straps, arranged transversely above the associated sheaths and having their ends fixed on the edges of these.

 According to an essential characteristic of the invention, the symmetrical lateral uprights each comprise a central device forming a connecting rod with stops comprising two pivot axes disposed at the two ends of said connecting rod and to which are respectively associated the articulated ends of the two branches of said upright, peripheral tightening straps adjustable against the tube, which are respectively associated with the free ends of said legs housed in the sheaths, being approximately semi-circular and comprising at least one front strap and one rear strap arranged at different transverse levels above each scabbard.

 According to another characteristic of 1 invention, the articulated ends of the two branches of each upright are bent outward symmetrically with respect to the central device so that the latter is separated from the tube, the sections of bands have a very slight elasticity in one direction. corresponding to their thickness and a short adjustable tightening strap against the tube, the ends of which are fixed on an inextensible support integral with said tube, is associated with the central device and arranged transversely above the latter.

 According to yet another characteristic of the invention, the stops of the central device with two pivot axes forming part of each upright allow each branch to pivot backwards at an angle of at least 900 between a folded position in which the two branches can be approximately parallel to each other and perpendicular to the link of the device and an elongated position in abutment in which the two branches and the link form an approximately rectilinear unit, reaching at most an angle of 1740.

 Preferably, each central device is in the form of a U-shaped yoke into which the articulated ends of the branches penetrate, the parallel walls of which are themselves connected at their ends by the two articulation axes passing through said ends of the branches and the bottom of which cooperates with notches cut in these articulated ends of the branches to form the stops.

Other characteristics and advantages of the invention will emerge more clearly from the description which follows, given with reference to the appended drawings in which
Figure 1 shows a schematic side view, slightly in perspective, of a toggle according to the invention
2 shows a partial rear view and on an enlarged scale of the right upright of the toggle joint shown in FIG. 1
Figure 3 shows a sectional view along
III-III of fig. 2.

 In these drawings, the same references designate the same elements.

 Referring to all the figures, the knee brace according to the invention is of the type comprising a flexible compression tube 1 preferably constituted by two layers of a two-way elastic fabric, which exerts on the leg a pressure calculated as a function the size of the knee to be fitted. This tube 1 is slightly flared from its lower part 2 corresponding to the tibia to its upper part 3 corresponding to the femur.

 The knee brace is also of the type comprising two lateral stiffening uprights, of which only the straight upright is visible in FIG. 1 and generally designated by 4, said uprights being preferably arranged symmetrically along the two sides of the tube 1. In known manner, each upright 4 is articulated and has upper 5 and lower 6 branches which are located under the in the form of sections of flat strips, the free ends 5a and 6a of which are shown in broken lines in FIG. 1 and are respectively housed in gussets or longitudinal sleeves 7 and 8. These sleeves are preferably made of a flexible and inextensible material such as leather and are respectively secured to the upper 3 and lower 2 parts of the tube 1.

 According to the invention, each of the lateral uprights 4 comprises a central device which will be studied in more detail below, which is designated as a whole by 9 and which generally forms a connecting rod with stops comprising two pivot axes 10 and 11 The pivot axes are mounted near the two ends of the link, the articulated ends 5b and 6b of the upper 5 and lower 6 branches of the upright 4 being pivotally mounted on said axes 10 and 11.

 The toggle is finally of the type comprising peripheral tightening straps 12 and 13 which are arranged transversely above the associated sleeves 7 and 8 and have their ends fixed in a known manner on the edges of the latter. According to 1 invention, these peripheral adjustable tightening straps against the tube 1 are approximately semi-circular and comprise at least one front strap 12a, 13a and a rear strap 12b, 13b which are arranged at different transverse levels above each sheath 7, 8.

 It should be noted that to make the knee support effective it is necessary to act by traction on the front straps 12a and 13a. The action of each strap 12a or 13a is made even more effective by being supported on the free end 5a or 6a of the upright, through the associated sheath 7 or 8. Preferably, each front strap 12a or 13a is flexible and inexten sible. It may consist of two strips of fabric each having one end fixed to the rear edge of the sleeves 7 and 8, one of the strips being very short and ending in a return loop 14, through which the other strip which passes ends with a self-gripping closure element. Adjusting the tension of these straps obviously makes it possible to adjust the tightening and holding of the upper and lower branches 5 and 6 against the leg of the wearer through the tube 1.

 The action of the straps 12a and 13a which urge the lateral uprights forward must be balanced by equal and opposite forces directed towards the rear of the toggle joint. This is the role played by the rear straps 12b and 13b which are formed like the front straps 12a and 13a and are arranged in different transverse planes so as to avoid any tourniquet effect. It is easily understood that a strap acting on a single circumference will brake the more the blood flow than the stressing effort of the strap will be important. This is an essential advantage of the knee brace strapping device according to the invention, which has the effect of allowing greater pressure to be exerted on the lateral uprights which are thus capable of ensuring better maintenance of the joint.

 It is obvious that the front straps 12a and 13a must tightly frame the patellar area while the rear straps 12b and 13b must be more apart from one another to release the popliteal area. This is another advantage offered by the semi-circular straps acting approximately on a half-circumference and not on a complete circumference. In fact, not only is the patellar area better maintained, but also the popliteal recess is completely free, which considerably increases the comfort provided by the kneepad according to the invention, the passage of straps at the popliteal recess being difficult to bear, especially in flexion.

 By way of example, the tube 1 comprises, preferably in the middle of its front face, a patellar opening surrounded by a damping rod 15 forming a guide and produced for example from silicone, centering and holding in place of the thus being perfectly insured. In contrast, the tube preferably comprises in the middle of its rear face, a large opening completely freeing the popliteal hollow and surrounded by a slight protective border 16, for example of fabric of the satin or velvety type.

 According to a preferred embodiment of the invention and with particular reference to FIG. 2, the articulated ends 5b and 6b of the two arms 5 and 6 of each upright 4 are bent outward symmetrically relative to the central device 9 so that the latter is slightly spaced from the tube. In addition, the sections of flat strips thus bent can have a very slight elasticity in a direction generally corresponding to their thickness.

 According to another essential feature of the invention, the toggle joint includes a short adjustable tightening strap 17 against the tube 1, the ends of which are fixed on an inextensible support, not shown, integral with said tube 1. This strap 17 is associated with the central device 9 and arranged transversely above the latter. It follows that the tightening of the device 9 against the tube 1 is a function of the tension of the strap 17.

 Under these conditions, the strap 17 makes the central articulation device 9 integral with the tube 1 and the entire toggle joint, which prevents the knee from bending apart from the lateral upright 4, the strap 17 obviously exerting its action on the zone situated between the two pivot axes 10 and 11, the knee not being hampered by the slight separation of the central device 9 from the tube 1 and the slight elasticity of the sections of flat strips making it possible to obtain a relatively constant pressure regardless of the knee flexion position. In fact the three parts constituting each upright, namely the two branches 5 and 6 and the central device 9, which are pivotally mounted with respect to each other, are all three held in an adjustable manner against the tube 1 thanks to their respective straps 12a and 12b, 13a and 13b as well as 17, said tube serving as support for the aforementioned functional elements, among which the central device 9 can be surrounded by a sheath of fabric not shown having a protective function.

 In addition, the two branches 5 and 6 and the central device 9 are preferably constituted by a light alloy, for example based on aluminum and copper, offering good resistance to deformation, in particular to prohibit certain lateral movements of the knee. . However, this alloy can be shaped in situ in order to adapt each amount to the asymmetrical anatomy of the knee and to the particular shape of the wearer's leg.

 According to another feature of the invention, the stops 18 and 19 of the central device 9 with two pivot axes 10 and 11 forming part of each upright 4 allow each branch 5 or 6 to pivot backwards at an angle of at least minus 90 between a folded position in which the two arms 5 and 6 may be approximately parallel to each other and perpendicular to the stop rod formed by the device 9 and an elongated position in which the two arms 5 and 6 and the rod 9 form an approximately rectilinear unit reaching at most an angle of 174.

 According to a preferred embodiment, each central device 9 forming a connecting rod with stops is in the form of a U-shaped yoke in which penetrate the articulated ends 5b and 6b of the branches 5 and 6, the parallel walls of which are themselves connected to their ends by the two articulation axes 10 and 11 crossing said ends of the branches and the bottom 20 of which cooperates with notches 18 and 19 respectively cut in these articulated ends of the branches to form the stops.

 For example, the U-shaped yoke comprises an L-shaped piece forming a wall 21 and the bottom 20 of the yoke, the other wall 22 of which is formed by a flat plate, the hinge pins 10 and II being able to be formed by rivets 23 respectively passing through the two walls and one of the articulated ends 5b and 6b of the branches 5 and 6.

 Furthermore, to facilitate donning and adapt the knee brace to the thigh and calf, the front of the tube 1 may have, at its upper 3 and lower 2 portions, short longitudinal slitting slots, not shown on the fig.

1, which are respectively associated with closure and holding straps 24 and 25 of the hook-and-loop type. For example, the slots may have a length or height of about 6 cm.

 It is understood that the present invention has been described and shown for explanatory purposes but in no way limitative and that any useful modification may be made to it, in particular in the field of technical equivalences, without going beyond its ambit.

Claims (10)

 1. Medical knee brace of the type comprising a flexible and slightly flared compression tube (1), constituted by an elastic fabric, two lateral stiffening uprights (4) arranged symmetrically along the tube, each upright being articulated and having upper branches ( 5) and lower (6) which are in the form of sections of flat strips and whose free ends (5a, 6a) are respectively housed in inextensible longitudinal sheaths (7, 8) integral with the upper (3) and lower parts (2) of the tube, and peripheral tightening straps (12, 13) arranged transversely above the associated sleeves and having their ends fixed on the edges of the latter, characterized in that the symmetrical lateral uprights (4) comprise each a central device (9) forming a connecting rod with stops comprising two pivot axes (10, 11) arranged at the two ends of said rod and which are respectively associated with the articulated ends (5b, 6b) of the two branches of said upright, the peripheral straps (12, 13) of adjustable clamping against the tube (1), which are respectively associated with the free ends (5a, 6a) of said branches (5, 6) housed in the sleeves (7, 8), being approximately semi-circular and comprising at least one front strap (12a, 13a) and one rear strap (12b, 13b) arranged at different transverse levels above of each scabbard.  2. Knee brace according to claim 1, characterized in that the articulated ends (5b, 6b) of the two branches (5, 6) of each upright (4) are bent outward symmetrically relative to the central device (9) so that the latter is spaced from the tube (1), the strip sections (5, 6) having a very slight elasticity in a direction corresponding to their thickness, and a short strap (17) for adjustable tightening against the tube such) , the ends of which are fixed on an inextensible support integral with said tube, being associated with the central device (9) and arranged transversely above the latter.  3. Knee brace according to one of claims 1 or 2, characterized in that the stops (18, 19) of the central device with two pivot axes (10, 11) forming part of each upright (4) allow each branch ( 5, 6) to be pivoted rearward at an angle of at least 90 "between a folded position in which the two arms (5, 6) can be approximately parallel to each other and perpendicular to the rod with stops formed by the device (9) and an elongated position in abutment in which the two branches (5, 6) and the link (9) form an approximately rectilinear assembly reaching at most an angle of 174.  4. Knee brace according to any one of claims 1 to 3, characterized in that each central device (9) is in the form of a U-shaped yoke in which penetrate the articulated ends (5b, 6b) of the branches ( 5, 6), the parallel walls of which are themselves connected at their ends by the two articulation axes (10, 11) passing through the said ends of the branches and the bottom (20) of which cooperates with notches (18, 19) respectively cut in these articulated ends of the branches to form the stops.  5. Knee brace according to claim 4, characterized in that the U-shaped clevis comprises an L-shaped part forming a wall (21) and the bottom (20) of the clevis, the other wall 22 of which is formed by a flat plate , the articulation axes (10, 11) being able to be formed by rivets (23) passing respectively through the two walls (21, 22) and one of the articulated ends (5b, 6b) of the branches (5, 6).  6. Knee brace according to any one of claims 1 to 5, characterized in that the two branches (5, 6) and the central device (9) consist of a light alloy which can be shaped in situ in order to adapt each post to the asymmetrical shape of the knee and the particular shape of the wearer's leg.  7. Knee brace according to one of claims 1 to 6, characterized in that the front straps (12a, 13a) are close to each other at the patellar area while the rear straps (12b, 13b ) are distant from each other at the popliteal area.  8. Knee brace according to one of claims 1 to 7, characterized in that the front of the tube (1) has at its upper (3) and lower (2) parts short longitudinal threading slots, which are respectively associated with closing and retaining straps (24, 25) of the hook-and-loop type.  9. Knee brace according to one of claims 1 to 8, characterized in that the tube (1) has in the middle of its front face a patellar opening surrounded by a damping rod (15) forming a guide.  10. Knee brace according to one of claims 1 to 9, characterized in that the tube (1) has in the middle of its rear face a large opening releasing the popliteal hollow and surrounded by a slight protective edge (16).