Adapted compression/splint orthosis for reinforcement of the calf musculoanoneurotic pump

Abstract

An orthosis (10) has an elastic compressive distal portion (14), extending upwards from the ankle, associated with an adjacent rigid splint proximal portion (16), enveloping the region of the calf 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 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 removing the orthosis in its finished state.

Claims

1. A method for tailoring an orthosis for medical compression/splinting of a lower limb to a measure of a patient's leg, said method comprising the steps of: obtaining an orthosis (10), said orthosis comprising: (i) an elastic compressive distal portion, adapted to cover an ankle, extending to before a beginning of a calf, at a point where an Achilles tendon joins calf muscles, the distal portion being made by knitting a knit yarn and a weft yarn, a dimensioning and a nature of the knit and weft yarns as well as a knit structure being selected in such a way to exert in a circumference direction, once that 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 (ii) a splint proximal portion, continuing the compressive distal portion and adjacent thereto, and enveloping, over a circumference thereof, a region of the calf comprised between a level of a point where the Achilles tendon joins the calf muscles and the level located below the tibial tuberosity; obtaining a hardenable biocompatible resin; placing the orthosis onto the patient's leg or a template representative of a morphology of the patient's calf; applying in situ on the orthosis over a whole circumference of a region of the splint proximal portion, said hardenable biocompatible resin; hardening the resin with the orthosis maintained on the patient's leg or the template; and removing the orthosis in a finished state, wherein the orthosis in the finished state is such that the splint proximal portion (16) is made rigid following the hardening of the resin and keeps corresponding dimensions of the patient's calf, which allows this splint proximal portion to perfectly fit a shape of the calf, while the compressive distal portion is still elastic to provide a therapeutic-level compression.

2. The method of claim 1, wherein the biocompatible resin is an evaporation-hardenable single component acrylic resin.

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

4. The method claim 1, wherein the splint proximal portion is a portion having, at a level of a calf maximum circumference, a high rigidity, of 152 mmHg/cm (202 mPa/cm).

5. The method of claim 1, wherein the splint proximal portion is a portion having, at a level of a calf maximum circumference, a moderate rigidity, of 52 mmHg/cm (72 mPa/cm).

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

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

8. The method of claim 1, wherein the biocompatible resin is applied with a brush, by controlled spraying or by dipping.

9. The method of claim 1, wherein in the finished state, the orthosis can be temporarily removed once it has been placed on said leg.

10. A kit to achieve a method according to claim 1, for tailoring an orthosis for medical compression/splinting of a leg of a patient, said leg comprising an ankle, an Achilles tendon, a tibial tuberosity, and a calf comprising calf muscles, said kit comprising: an orthosis comprising: an elastic compressive distal portion, adapted to cover said ankle, extending to before a beginning of said calf, at a point where the Achilles tendon joins said calf muscles, the elastic compressive distal portion being made by knitting a knit yarn and a weft yarn, a dimensioning and a nature of the knit and weft yarns as well as a knit structure being selected in such a way to exert in a circumference direction, once the orthosis has been placed on said leg, an elastic return likely to produce a compression of the leg at a desired therapeutic level of pressure, and a splint proximal portion, continuing the compression distal portion and adjacent thereto, and enveloping, over a circumference thereof, a region of the calf comprised between a level of the point where the Achilles tendon joins the calf muscles and a level located below the tibial tuberosity, and a hardenable biocompatible resin, separated from the orthosis.

11. A kit according to claim 10, wherein the elastic compressive distal portion and the splint proximal portion are both knitted continuously during a single sequence on a knitting machine.

12. A method to improve calf musculo-sponeurotic pump efficiency of a patient, wherein an orthosis manufactured according to claim 1 is placed on a leg of the patient.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) 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.

(2) FIG. 1 is an overall view of an orthosis according to the invention, in its free state.

(3) FIG. 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 orthosis on the limb are indicated.

(4) FIG. 3 illustrates the successive steps of the method of implementation according to the invention, intended to tailor the orthosis to the measure of the patient's leg.

(5) In FIGS. 1 and 2, the reference 10 generally denotes the orthosis of the invention, which is a knitted orthosis made using conventional methods on a circular knitting machine. This tubular-shaped orthosis 10 comprises 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 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.

(6) This sock-shaped configuration is not limitative, and 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).

(7) The various adjoining portions of the above-described orthosis are knitted continuously on the circular knitting 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 part 12, if a tip is present.

(8) FIG. 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:

(9) B: ankle, at the point of its minimum circumference;

(10) B1: point where the Achilles tendon joins the calf muscles;

(11) C: calf, at the point of its maximum circumference;

(12) D: just below the tibial tuberosity (i.e. just below the knee);

(13) E: at the center of the kneecap and above the back of the knee (i.e. at the level of the popliteal fossa);

(14) F: at the middle of the thigh; and

(15) G: at the top of the thigh.

(16) The calf is the limb segment comprised between the levels B1 and D, and the ankle is the limb segment located below the level B1.

(17) The pressure exerted at the altitude B (at the minimum perimeter of the ankle) is the pressure prescribed for the selected standard class (I, II, III, or IV).

(18) The pressure values may be read, for example, using a dynamometer according to the above-mentioned standard 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.

(19) The pressure exerted on the ankle at the point of its minimum circumference (level B) by the elastic compressive distal portion 14 must be an effective therapeutic pressure. The following values may be retained, depending on the patient's needs: 10 to 20 mmHg (13 to 27 hPa) for a relatively low compression of the ankle; 20 to 30 mmHg (27 to 40 hPa) for a moderate compression of the ankle.

(20) The elastic compressive distal portion 14 that produces these therapeutic pressures is made from a knit fabric of more or less tight texture with incorporation of an elastic weft yarn, generally a covered spandex yarn, e.g. using: as the weft yarn, a yarn such as spandex or a mixture of spandex and elasto-diene (synthetic rubber latex), covered with polyamide and/or cotton; and as the knit yarn (stitch yarn), also a polyimide and/or cotton covered spandex yarn, having preferably a lower size (weight per unit length) than the weft yarn.

(21) Characteristically of the invention, the proximal portion 16 is a splint portion (i.e. a portion that is essentially non-elastic in the final state of the orthosis), 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 muscles) 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 belongs to this region covered by the proximal portion 16; and in the circumference direction; over the whole circumference of the calf.

(22) 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 dimensions of the patients 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 degree of effectiveness.

(23) As regards the rigidity R.sub.c of this splint proximal portion 16, the following values may be retained (according to the above-mentioned European Pre-Standard XP ENV 12718:2001): for a strong splinting:

(24) R.sub.c=152 mmHg/cm (202 hPa/cm) for a moderate splinting:

(25) R.sub.c=5 mmHg/cm (7 hPa/cm).

(26) These values for R.sub.c are measured at the altitude C, i.e. at the point of maximum circumference of the calf.

(27) By acting separately, on the one hand, on the elasticity 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 combine 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; low compression at the ankle moderate splint at the calf; or moderate compression at the ankle moderate splint at the calf.

(28) Very advantageously, the distal portion 14 and the 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 proximal portion 16 may thus be knitted with the same types of yarns than the elastic compressive distal portion 14, 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.

(29) The product may be knitted according to usual techniques, on a conventional circular knitting machine, such as a Santoni knitting machine.

(30) Characteristically of the invention, the non-elastic splint proximal portion 16 is obtained by adding a resin.

(31) This operation is made as illustrated in FIG. 3.

(32) The orthosis 10 that has just been knitted in the conventional manner is initially in the form of a standard product, i.e. a product that is not tailored to measure (step a); it is only provided, as for the conventional EVC orthoses, and even for any cloth article, suitable standard sizes, to be selected in a size grid.

(33) 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 marks such as the marks 24, visible by transparency once the orthosis is slipped on.

(34) The following step (step c) consists in adding in the calf region, i.e. between the marks 24, a biocompatible resin, for example by application with a brush 26, by controlled spraying or by dipping.

(35) An example 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 rigidification of papers and fabrics, the creation of lampshades, etc.

(36) 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, in the field of body molding.

(37) This resin is applied until saturation of the textile, and is left to dry, by evaporation.

(38) In an exemplary implementation, it has been observed that, after hardening by evaporation, 12 g of resin were added to the sock with respect to the initial weight of the latter, for an application in the calf region as defined hereinabove, over the whole circumference of the sock. The final rigidity obtained was about 15 mmHg/cm (20 mPa/cm).

(39) The orthosis may then be removed from the template (step d). It will then have its definitive shape, tailored to measure, with a splint proximal portion 16 that has become rigid and that has taken a shape that perfectly fits the curve and the dimensions of the patient's calf, and an elastic compressive distal part 14, which 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), providing a therapeutic-level compression of the lower limb.