AU2012258309A1 - Adapted compression/splint orthosis for reinforcement of the calf musculo-aponeurotic pump - Google Patents

Abstract

Adapted compression/splint orthosis for reinforcement of 5 the calf musculo-aponeurotic pump The orthosis (10) comprises an elastic compressive distal portion (14), extending upwards from the ankle, associated with an adjacent rigid splint proximal portion 10 (16), enveloping the region of the calf comprised between the level of the point where the Achilles tendon joins the calf muscles and the level located below the tibial tuberosity. This rigid splint proximal portion (16) is an essentially non-elastic, deformable tubular portion, made 15 by: placing the orthosis onto a template representative of the morphology of the patient's calf; applying in situ on the orthosis, in the region of the splint proximal portion, a hardenable biocompatible resin; hardening the resin with the orthosis maintained on the template; and 20 removing the orthosis in its finished state. (Figure 3) 10F- - -- -14 B1 B l14 FIG.1 FL-2 (a) (b) (c) (d) FIG-3

Description

AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION Standard Patent Applicant (s) INNOTHERA TOPIC INTERNATIONAL Invention Title: Adapted compression/splint orthosis for reinforcement of the calf musculo-aponeurotic pump The following statement is a full description of this invention, including the best method for performing it known to me/us: 1A The invention relates to the elastic venous compres sion (EVC) orthoses, indicated in the various clinical manifestations of venous insufficiency of the lower limbs. Such orthoses, formerly known as "elasticated stock 5 ings (or socks)" or "elasticated tights", are textile med ical devices that produce a therapeutic effect by compres sion of the lower limbs, in contrast to the "sustain stockings" (also "support stockings" or "anti-fatigue stockings") and to the "fashion stockings", which are not 10 medical devices with a therapeutic purpose. EVC orthoses are designed to produce a therapeutic effect by compression of the lower limb over a greater or lesser extent, usually with an upwardly degressive pro file starting from the ankle. Depending on the type of 15 orthosis, the pressure measured at the ankle may vary from 10 to more than 36 mmHg (i.e. from 13 to 48 hPa, the unit mmHg being however commonly used as a pressure mea surement unit in the field of phlebology and medical com pression). In France, stockings are divided into four 20 textile classes according to the ASQUAL system, namely Class I (13 to 20 hPa ~ 10 to 15 mmHg at the ankle), class II (20 to 27 hPa ; 15 to 20 mmHg), class III (27 to 48 hPa 20 to 36 mmHg), and class IV (> 48 hPa ; > 36 mmHg). These compression classes may be different in 25 other countries. For a high compression of the lower limbs, such or thoses are made from a knit fabric of more or less tight texture with incorporation of an elastic weft yarn, gen erally a covered spandex yarn. 30 More precisely, under the effect of being placed on the limb, the tight textile of the orthosis exerts a com pression resulting from the return force of the elastic fibers that make up the material, and the application of such elastic return forces on the perimeter of the out 35 line generates at a given point, according to the Laplace 2 law, a local pressure that is inversely proportional to the radius of curvature of the outline at that point. This pressure is the "textile pressure" as defined and calculated within the meaning of the French standard 5 NF G 30-102, part B. The term "pressure" will be used he reinafter to refer to the mean of the pressures locally exerted at a given altitude along an outline of the leg. The knit and the yarns, as well as the dimensioning of the rows of stitches, are selected so that predeter 10 mined pressures are applied at different altitudes along the lower limb, e.g. at the height of the ankle, at the start of the calf, at the calf, at the popliteal fossa, etc., all the way up to the top of the thigh, such alti tudes being conventionally denoted B, C, ... , G. These 15 various pressures are defined for each class with refer ence to metrological templates such as the model leg of the French standard NF G 30-102 part B, Appendix B, cor responding to the "Hohenstein" model leg according to the German system RAL-GZ 387, or as defined in the European 20 Pre-Standard XP ENV 12718:2001. The above-mentioned characteristic of pressure pro file degressivity consists in exerting a maximum pressure at the ankle, then a degressive pressure from the ankle to the calf or to the thigh. It is based on the fact that, 25 in an orthostatic situation, the intravenous pressure is degressive from the ankle to the calf, then up to the thigh. It is therefore logical to apply a corresponding, and hence degressive, counter-pressure, to proportionally reduce the venous diameters and to induce an anti-stasis 30 effect. In a dynamic situation, such as during walking, the situation is physiologically different, the calf being the key element of the lower limb venous hemodynamics. The importance of the effect of the "muscle pump" or 35 "calf musculo-aponeurotic pump" (CMAP) has notably been 3 described in terms of return venous blood flow, where the physiological cycles of contraction and relaxation of the calf muscles give rise, via the opening and closing ac tions of the venous valves, to emptying and filling of 5 the lower limb venous network, which results in a lower ing of the venous pressure at the ankle. The CMAP effi ciency decreases progressively with the age of the sub jects, which is accompanied by a residual venous hyper pressure that naturally aggravates chronic venous insuff 10 ficiencies. Chronic venous insufficiency is therefore characte rized by a failure of this muscle pump effect, which hence plays a major role in the genesis of the trophic troubles such as ulcers. 15 The starting point of the invention is the search for a means making it possible to improve the CMAP effi ciency, or even to take over from it, thanks to a com pressive orthosis that is better suited to this role than the orthoses that may have been proposed up to now and 20 that are degressive, because they are based on the analy sis of the venous pressures resulting from orthostatic situations. However, the study of venous physiology, in particu lar using the recent compression modeling and simulating 25 tools such as those described in the WO 2006/087442 Al (Laboratoires Innothera) , shows that the effectiveness of an EVC orthosis rather lies in the CMPA efficiency im provement, providing that it is possible to make it oper ate. 30 The FR 2 824 471 B1 (Rodier) describes an approach consisting in providing an "elective compression/ splint ing" by means of a differentiated-knit multizone stock ing, associating a very elastic knit region at the foot and the ankle, followed by a not very elastic knit region 35 from the bottom of the calf up to the popliteal fossa, 4 and continued by again a very elastic knit region from the knee up to the top of the thigh. The basic idea con sists in providing zones with a rather compressive effect (foot, ankle and thigh) on either side of a zone with a 5 rather splinting effect (calf) . This latter zone of the orthosis will produce less effect at rest than those that surround it. But, during contractions of the calf muscle, it will exert an increased compression, increasing the power and reinforcing the emptying effect of the CMAP. 10 In this respect, it should be specified that the terms "compression" and "splinting" define clearly dif ferent effects, even though they are sometimes confused in the common language: - "compression" is the effect produced by an elastic 15 orthosis, both at rest and on effort, on a limb segment, as a result of the more or less strong return forces of the elastic fibers of this orthosis. These forces act in an almost constant manner on the limb: at rest, the com pression is present at the nominal pressure value, and on 20 effort, the effect of this compression is slightly in creased by the contraction of the muscle masses; - conversely, "splinting" is the effect produced by an orthosis that acts in a differentiated manner (effort/ rest) on a limb segment, under the action of a structure 25 considered as being inelastic (but deformable), for exam ple a non-elastic bandage, also referred to as "short stretch bandage". At rest, this type of bandage exerts a low pressure, or even no pressure; on the other hand, during muscle contraction, it goes against the local vo 30 lume increases of the calf, which comes into abutment with the non-elastic structure, the pressure being there fore strongly increased. The splinting is thus effective and active on effort, and almost inactive at rest. It is customary in the scientific literature on this 35 subject to consider that an orthosis is a splint, or "ri- 5 gid", orthosis when it produces an increase of at least 10 mmHg (13 hPa) per centimeter of increase of the limb circumference at the point located where the Achilles tendon-joins the calf muscles. The term "rigidity" is un 5 derstood herein within the meaning of the definition of the European Pre-Standard XP ENV 12718:2001, i.e. "the in crease of compression per centimeter of increase of leg circumference, expressed in hectopascals per centimeter and/or in millimeters of mercury per centimeter". 10 It is in order to denote these two different notions that the two respective terms "compression" (or "compres sive") and "splinting" (or "splint") will be used herei nafter. With regard to these definitions, the proposal of 15 the above-mentioned FR 2 824 471 B1, which implements on ly yarns and stitches that are more or less elastic over the height of the orthosis, produces only a very partial splinting effect at the calf. Other orthoses consisted of zones, all of which are 20 elastic but with a differentiated elasticity are proposed by the EP 0 934 043 B1 (Couzan) or EP 1 240 880 A2 (Stolk). These two documents teach the making of a stock ing or a sock with a less rigid (more elastic) zone in the region of the calf, respectively uniformly over the 25 whole circumference of the calf, or only in the posterior region thereof. The orthoses described, which are devoid of any inelastic structure, thus provide no "splinting" effect, within the above-explained meaning, with an effect of abutment of the calf against a non-elastic structure, 30 in case of local volume increase of the latter. The same is true for the product disclosed in the WO 2006/134875 Al, which provides discrete elements added at selected locations of an "anti-fatigue" sock or stocking, and intended to increase the sensation of compression 35 felt by the wearer, hence without any splinting purpose 6 or function. Moreover, none of these elements extends over the circumference of the calf, and therefore none of them can generate a splinting, since they cannot create an in elastic obstacle to the volume increase of the calf on 5 effort. In addition, from the technological point of view, in practice, it proves to be difficult to make all of those prior art "multizone" structures, taking into ac count the difficulty that exists in setting the knitting 10 machine to obtain the required variable elasticity pro files, with very abrupt transitions between very hetero geneous textures that correspond to the different zones of the stocking or the sock. On the other hand, and above all, those orthoses 15 that may be referred to as "semi-splint orthoses" are not specifically fitted to a given patient. In concrete terms, the practitioner just selects an orthosis from a grid of sizes after having measured the perimeter of the ankle and of the calf. In practice, this leads to a compromise so 20 lution that does not take into account the real morpholo gy of the calf, which may vary widely from one patient to another and which cannot be suitably described by merely measuring the maximum perimeter of the calf. This drawback is particularly increased within the 25 framework of products that are supposed to produce a real splinting effect (within the above-defined meaning), since the reinforcement of the CMAP effect depends on a precise fitting of the non-elastic structure to the concerned limb segment, over the whole extent thereof: if the non-elastic 30 structure is not in close contact with the limb at rest, it will produce only very little effect for a small or moderate volume increase of the muscle; on the contrary, if its size is too small, it will exert stress on the limb even at rest, with harmful effects on blood circula 35 tion, in addition to an oppressive sensation that could 7 make the orthosis particularly uncomfortable to wear for the patient. It thus appears desirable that orthoses can be made, which provide a real splinting effect on the calf via a 5 non-elastic structure (and not a structure with a lesser elasticity), fitted to the exact morphology of the limb segment of each patient. The non-elastic structure must however be deforma ble, unlike for example the product disclosed by the EP 1 10 656 916 Al, which is a non-deformable orthopedic splint orthosis, intended to form a splint for immobilizing a traumatized limb: the splinting is not of same nature than that of the present invention, which must be imple mentable by an item, such as a stocking or a sock, liable 15 to be put on and removed at will by the patient, and which, once in position, do not hinder the movements of the limb enveloped by the orthosis. If it is desired to have a made-to-measure, rigid splint product, specifically fitted to the patient, a 20 first solution consists in using multilayer bandages, with the well-known difficulty in properly adjusting the bandage, neither too tight (it would squeeze the calf) nor too loose (it would produce no effect), hence a highly "operator-dependent" result. As explained hereinabove, the 25 adjustment of rigid splint product is highly critical, unlike a compressive elastic structure that is much more tolerant. Moreover, the bandage needs to be regularly redone, each time with the same care for a good adjustment. 30 The FR 2 912 644 (Mollard et al.) discloses such a technique with, in addition, superimposition of a com pressive element and a splint element. The splint element is a strip of perforated ultra-thin film, for example of polyethylene, packed as a roll. This film is unrolled 35 around the limb in such a way to envelop the latter, then 8 a splint stocking is placed on the bandage so at the pro vide the compressive effect. But, in addition to the par ticular skill required for placing the bandage, once the latter has been placed, no possibility exists to readjust 5 it, except redoing the whole process. Finally, this prod uct is single use and does not permit a temporary removal of the orthosis, for example for the time to make an ex amination or to change a dressing. For those reasons, patients generally prefer using 10 another solution, in the form of knitted orthoses to be slipped on, which are handier and more aesthetically pleasant. The matter is then to make a made-to-measure, rigid product, perfectly fitted to the particular morphology of 15 the patient. The technique consists in measuring the calf in the more complete way possible, with measurements at several heights. The orthosis is then knitted on a flat knitting machine, and shaped through a seam made all along its length, which requires an additional step of making. 20 It will be understood that such a technique of full made to-measure tailoring is lengthy to implement, complicated and thus expensive, and does not allow the rigid splint products to become widespread, despite their manifest therapeutic advantages. 25 The problem of the invention is thus to be capable of making a splint orthosis (a rigid product) able to be in the form of a final product that is "made-to-measure", hence perfectly fitted to the patient's morphology, but that do not even so require to be made using convention 30 al, lengthy and expensive "made-to-measure" techniques. In particular, it will be seen that the invention can be implemented i) on a circular knitting machine (and not a flat knitting machine, which would require an addi tional step of making for sewing the seam) ii) making a 35 standard product, hence with a possibility to be made at 9 a reasonable cost and in large quantities. And this with a new EVC orthosis structure: - that reinforces the beneficial effects of the CMAP by an appropriate splinting of the calf; 5 - that is technologically easy to make; and - that can be easily fitted to the very different leg morphologies encountered in the population of the concerned patients. It will also be seen that the invention makes it 10 possible to obtain an EVC orthosis for the lower limb that applies on the calf no longer a more or less streng then compression, but a real splinting, by placing around the calf an essentially rigid, i.e. non-elastically de formable, element. In addition, with this high rigidity 15 at the calf (splinting effect) will be associated a low rigidity at the ankle (compression effect). Indeed, a high rigidity at the calf is considered as a means for optimizing the CMAP, which is the main motor of the venous return in the lower limbs. But the high ri 20 gidity at the calf has to be associated with a low rigid ity (and hence a high deformability) at the ankle to en sure that the product will be easy to put on, to take off, and will be well tolerated - in particular to avoid a too high compression, which would rapidly become intolerable, 25 in particular for a patient who is confined in bed or in active. A solution to that problem is described by the ap plicant in the EP 2 452 658 Al (published on May 16, 2012, hence after the priority date of the present appli 30 cation). This solution consists in incorporating, during the making, a thermoformable yarn to the weft of the or thosis, in the region of the calf. The orthosis is then placed on a model and locally heated so as to become in extensible, and hence to form a splint, in this region, 35 under the effect of changes of the thermoformable yarn 10 mechanical characteristics. However, this solution requires a modification of the knitting process so that the thermoformable yarn can be incorporated during the making of the orthosis. 5 The present invention aims to offer an alternative to this solution, which does not suffer from this draw back and which can be implemented based on an orthosis of conventional structure, without modification of the knit ting process. 10 Essentially, the basic idea of the invention consists in making a compressive orthosis by means of conventional techniques, but with integrating into the product a splint portion made by applying and drying a suitable biocompat ible resin, making it possible to obtain a hardening of 15 the textile in the region where this resin has been ap plied. If this operation is made with the orthosis placed on the patient's leg - or, preferably, on a template rep resentative of the morphology of this leg, to avoid the 20 patient the annoyance caused by the operation - and if the application of resin is properly located in the calf region, a compressive/splint product perfectly fitted to the shape of the patient's calf will finally be obtained. Therefore, the product thus obtained makes it possi 25 ble to apply an efficient splinting to the calf, thanks to the splint portion, whose shape will be personalized as a function of the patient, this region being in a way "molded in place" on the patient's calf. This splint por tion in the calf region will be associated with a conven 30 tional compressive portion over the remainder of the leg, especially in the ankle region. More precisely, the invention proposes an EVC ortho sis having the same purpose as the above-mentioned FR 2 824 471 B1, i.e. a medical compression orthosis in the 35 form of a sock, a stocking or a pair of tights intended 11 to act specifically on the CMAP. Such an orthosis comprises, in a manner known in it self, (i) an elastic compressive distal portion, adapted to cover the ankle, extending to before the beginning of 5 the calf, at the point where the Achilles tendon joins the calf muscles, such point being generally denoted Bl, and (ii) a splint proximal portion, continuing the com pressive distal portion and adjacent thereto, and enve loping, over the circumference thereof, a region of the 10 calf comprised between the level of the point where the Achilles tendon joins the calf muscles and the level lo cated below the tibial tuberosity. The distal portion is made by knitting a knit yarn and a weft yarn, the dimensioning and the nature of the 15 knit and weft yarns as well as the knit structure being selected in such a way to exert in the circumference di rection, once the orthosis has been placed on the limb, an elastic return force likely to produce a compression of the limb at a desired therapeutic level of pressure. 20 The splint proximal portion is a deformable tubular por tion that is knitted in continuation of the elastic com pressive distal portion. Characteristically of the invention, the splint prox imal portion is essentially non-elastic, and incorporates 25 a hardened biocompatible resin, for example an evapora tion-hardenable single-component acrylic resin. The knit yarn may in particular be a polyamide and/or cotton covered spandex yarn, and the weft yarn a polya mide and/or cotton covered spandex yarn. 30 The proximal portion may be a portion with, at the level of the calf maximum circumference, a high rigidity, of 15 ± 2 mmHg/cm (~ 20 ± 2 hPa/cm), or a moderate rigid ity, of 5 + 2 mmHg/cm (~ 7 + 2 hPa/cm). The elastic compressive distal portion may be a low 35 compression portion adapted to exert a pressure of 10 to 12 20 mmHg (13 to 27 hPa), or a moderate compression portion adapted to exert a pressure of 20 to 30 mmHg (27 to 40 hPa) at the level of the ankle minimum circumference. The invention also provides a specific method for 5 tailoring an orthosis for medical compression / splinting of the lower limb to the measure of a patient's leg*. This method comprises the steps of: obtaining an or thosis as described above, in a rough initial state, with no biocompatible resin; placing the orthosis onto a tem 10 plate representative of the morphology of the patient's calf; applying in situ on the orthosis, in the region of the splint proximal portion, a hardenable biocompatible resin; hardening the resin with the orthosis maintained on the template; and removing the orthosis in its fi 15 nished state. The orthosis has then a splint proximal portion made rigid following the hardening of the resin and keeping the corresponding dimensions of the patient's calf, which allows this splint proximal portion to per fectly fit the shape of the calf. 20 An exemplary embodiment of the invention will now be described, with reference to the appended drawings, in which the same reference numbers designate identical or functionally similar elements throughout the figures. 25 Figure 1 is an overall view of an orthosis according to the invention, in its free state. Figure 2 is an elevation view of the same orthosis, slipped on a limb, wherein the various standard altitudes to which are measured the pressures applied by the ortho 30 sis on the limb are indicated. Figure 3 illustrates the successive steps of the me thod of implementation according to the invention, in tended to tailor the orthosis to the measure of the pa- 13 tient's leg. 0 In Figures 1 and 2, the reference 10 generally de notes the orthosis of the invention, which is a knitted 5 orthosis made using conventional methods on a circular knitting machine. This tubular-shaped orthosis 10 com prises a portion 12 that envelops the foot and a portion of the leg, with a distal portion 14 enveloping the ankle and a proximal portion 16 enveloping the calf. The whole 10 extends up to a level located below the knee, when the orthosis is a "knee-length" sock (or "calf-length sock"). In the latter case, the orthosis is terminated by a "ribbed type" knitted terminal portion 18. This sock-shaped configuration is not limitative, and 15 the invention may also be implemented as a "thigh-length" stocking, extended by a compressive thigh portion 20. The orthosis of the invention may also be made as a pair of tights, and/or be devoid of a foot portion 12 ("footless" type stocking or pair of tights). 20 The various adjoining portions of the above-described orthosis are knitted continuously on the circular knit ting machine, i.e. making this orthosis does not require any step of making for assembling distinct parts, except naturally the operations for sewing the tip at the foot 25 part 12, if a tip is present. Figure 2 shows the various altitudes of the lower limb as defined by the morphological system specified in the introduction (the "Hohenstein" model leg) , using the standard notation: 30 B: ankle, at the point of its minimum circumference; Bl: point where the Achilles tendon joins the calf muscles; C: calf, at the point of its maximum circumference; 14 D: just below the tibial tuberosity (i.e. just below the knee); E: at the center of the kneecap and above the back of the knee (i.e. at the level of the popliteal fossa); 5 F: at the middle of the thigh; and G: at the top of the thigh. The calf is the limb segment comprised between the levels B1 and D, and the ankle is the limb segment lo cated below the level Bl. 10 The pressure exerted at the altitude B (at the mini mum perimeter of the ankle) is the pressure prescribed for the selected standard class (I, II, III, or IV). The pressure values may be read, for example, using a dynamometer according to the above-mentioned standard 15 NF G 30-102 part B, after the orthosis has been slipped on a reference template such as the Hohenstein model leg prescribed by that standard. The pressure exerted on the ankle at the point. of its minimum circumference (level B) by the elastic com 20 pressive distal portion 14 must be an effective therapeu tic pressure. The following values may be retained, de pending on the patient's needs: - 10 to 20 mmHg (13 to 27 hPa) for a relatively low compression of the ankle; 25 - 20 to 30 mmHg (27 to 40 hPa) for a moderate com pression of the ankle. The elastic compressive distal portion 14 that pro duces these therapeutic pressures is made from a knit fa bric of more or less tight texture with incorporation of 30 an elastic weft yarn, generally a covered spandex yarn, e.g. using: - as the weft yarn, a yarn such as spandex or a mix ture of spandex and elasto-diene (synthetic rubber latex) covered with polyamide and/or cotton; and 35 - as the knit yarn (stitch yarn), also a polyamide 15 and/or cotton covered spandex yarn, having preferably a lower size (weight per unit length) than the weft yarn. Characteristically of the invention, the proximal portion 16 is a splint portion (i.e. a portion that is 5 essentially non-elastic in the final state of the ortho sis), of tubular shape, extending: - in the vertical direction: over the extent of the calf, i.e. over the region comprised between the level B1 (junction between the Achilles tendon and the calf mus 10 cles) and the level D (below the knee), or at least over the major part of this region; it should be observed that the ankle (region extending around the level B) never be longs to this region covered by the proximal portion 16; and 15 - in the circumference direction: over the whole circumference of the calf. This non-elastic portion is made to measure, in the manner explained hereinafter, i.e. it has an external configuration that is accurately fitted to the shape and 20 dimensions of the patient's calf. As a result, once the orthosis slipped on the limb, this portion exerts the wanted splint effect, i.e., at rest', it exerts essentially no splinting force but, on effort, it opposes to the limb a rigidity providing the splint effect at the desired de 25 gree of effectiveness. As regards the rigidity Rc of this splint proximal portion 16, the following values may be retained (accord ing to the above-mentioned European Pre-Standard XP ENV 12718:2001): 30 - for a strong splinting: Rc = 15 ± 2 mmHg/cm (~ 20 + 2 hPa/cm) - for a moderate splinting: Rc = 5 mmHg/cm (~ 7 hPa/cm). These values for Rc are measured at the altitude C, 35 i.e. at the point of maximum circumference of the calf.

16 By acting separately, on the one hand, on the elas ticity of the compressive distal portion 14 at the ankle, and on the other hand, on the rigidity of the splint proximal portion 16 at the calf, it is possible to com 5 bine several compression/splinting effects, for example: - low compression at the ankle / high splint at the calf; - moderate compression at the ankle / high splint at the calf; 10 - low compression at the ankle / moderate splint at the calf; or - moderate compression at the ankle / moderate splint at the calf. Very advantageously, the distal portion 14 and the 15 proximal portion 16 are both knitted continuously during a single sequence on the knitting machine, which avoids any step of making for assembling added parts. The prox imal portion 16 may thus be knitted with the same types of yarns than the elastic compressive distal portion 14, 20 i.e.: - as the weft yarn, a polyamide and/or cotton covered spandex yarn; and - as the knit yarn, a polyamide and/or cotton covered spandex yarn of lower size. 25 The product may be knitted according to usual tech niques, on a conventional circular knitting machine, such as a Santoni knitting machine. Characteristically of the invention, the non-elastic splint proximal portion 16 is obtained by adding a resin. 30 This operation is made as illustrated in Figure 3. The orthosis 10 that has just been knitted in the conventional manner is initially in the form of a stan dard product, i.e. a product that is not tailored to measure (step a) ; it is only provided, as for the conven 35 tional EVC orthoses, and even for any cloth article, 17 suitable standard sizes, to be selected in a size grid. This orthosis is then placed (step b) on a template 22 corresponding to the patient's morphology in the calf region. This region may in particular be delimited by 5 marks such as the marks 24, visible by transparency once the orthosis is slipped on. The following step (step c) consists in adding in the calf region, i.e. between the marks 24, a biocompati ble resin, for example by application with a brush 26, by 10 controlled spraying or by dipping. Anexample of resin that can be used for that purpose is, for example, the resin Plastidurex, which is a single component acrylic resin sold by REAL Composites, and which is used, for example, in the field of decoration for the 15 rigidification of papers and fabrics, the creation of lampshades, etc. Another resin that can be used is the resin SILDOC RTV AD 35, which is a two-component silicone resin, also sold by REAL Composites, and which is used, for example, 20 in the field of body molding. This resin is applied until saturation of the tex tile, and is left to dry, by evaporation. In an exemplary implementation, it has been observed that, after hardening by evaporation, 12 g of resin were 25 added to the sock with respect to the initial weight of the latter, for an application in the calf region as de fined hereinabove, over the whole circumference of the sock. The final rigidity obtained was about 15 mmHg/cm (20 mPa/cm). 30 The orthosis may then be removed from the template (step d) . It will then have its definitive shape, "tai lored to measure", with a splint proximal portion 16 that has become rigid and that has taken a shape that perfect ly fits the curve and the dimensions of the patient's 35 calf, and an elastic compressive distal part 14, which 18 results in a product associating a high rigidity at the calf (splint proximal portion 16) and a low rigidity at the ankle (elastic compressive distal portion 14), pro viding a therapeutic-level compression of the lower limb. 5 It is to be understood that, if any prior art publi cation is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country. 10 In the claims which follow and in the preceding de scription of the invention, except where the context re quires otherwise due to express language or necessary im plication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive 15 sense, i.e. to specify the presence of the stated fea tures but not to preclude the presence or addition of further features in various embodiments of the invention. 20 3886722 1 (GHMatters) P91954 AU

Claims (8)

1. An orthosis for medical compression/ splinting of the lower limb, in the form of a sock, a stocking or a 5 pair of tights, such orthosis (10) comprising: - an elastic compressive distal portion (14), adapted to cover the ankle, extending to before the be ginning of the calf, at the point where the Achilles ten 10 don joins the calf muscles, said distal portion being made by knitting a knit yarn and a weft yarn, the dimensioning and the nature of the knit and weft yarns as well as the knit structure be ing selected in such a way to exert in the circumference 15 direction, once the orthosis has been placed on the limb, an elastic return force likely to produce a compression of the limb at a desired therapeutic level of pressure; and - a splint proximal portion (16), continuing the 20 compressive distal portion and adjacent thereto, and en veloping, over the circumference thereof, a region of the calf comprised between the level (B1) of the point where the Achilles tendon joins the calf muscles and the level (D) located below the tibial tuberosity; 25 said splint proximal portion being a deformable tu bular portion knitted in continuation with the elastic compressive distal portion, said orthosis being characterized in that the splint proximal portion: 30 - is essentially non-elastic, and - incorporates a hardened biocompatible resin.

2. The orthosis of claim 1, wherein the biocompatible resin is an evaporation-hardenable single-component acryl ic resin. 35

3. The orthosis of claim 1, wherein the knit yarn 20 and/or the weft yarn is a polyamide and/or cotton covered spandex yarn.

4. The orthosis of claim 1, wherein the splint prox imal portion is a portion having, at the level of the 5 calf maximum circumference, a high rigidity, of 15 + 2 mmHg/cm (~ 20 + 2 mPa/cm).

5. The orthosis of claim 1, wherein the splint prox imal portion is a portion having, at the level of the calf maximum circumference, a moderate rigidity, of 5 + 2 10 mmHg/cm (~ 7 + 2 mPa/cm).

6. The orthosis of claim 1, wherein the elastic com pressive distal portion is a low compression portion adapted to exert a pressure of 10 to 20 mmHg (13 to 27 hPa) at the level of the ankle minimum circumference. 15

7. The orthosis of claim 1, wherein the elastic com pressive distal portion is a moderate compression portion adapted to exert a pressure of 20 to 30 mmHg (27 to 40 hPa) at the level of the ankle minimum circumference.

8. A method for tailoring an orthosis for medical 20 compression/splinting of the lower limb to the measure of a patient's leg, said method comprising the steps of: - obtaining an orthosis (10) according to one of claims 1 to 7, in a rough initial state, with no biocom patible resin; 25 - placing the orthosis onto a template representa tive of the morphology of the patient's calf; - applying in situ on the orthosis, in the region of the splint proximal portion, a hardenable biocompatible resin; 30 - hardening the resin with the orthosis maintained on the template; and - removing the orthosis in its finished state, the orthosis in its finished state having a splint proximal portion (16) made rigid following the hardening 35 of the resin and keeping the corresponding dimensions of 21 the patient's calf, which allows this splint proximal por tion to perfectly fit the shape of the calf.