Elastic venous compression orthosis

Abstract

An elastic venous compression orthosis having a top part and a leg part, the top part and the leg part having a top part knit thread and leg part knit thread, respectively, defining a network of knitted meshes, and a top part weft thread and leg part weft thread, respectively, each weft thread having a core which is covered by means of a covering thread, the orthosis being characterized in that the core of the top part weft thread and the one or more covering threads of the top part weft thread are made of elastane, and the core of the top part weft thread has a linear density of less than 0.7 times that of the core of the leg part weft thread.

Claims

1. Elastic venous retention and/or compression orthosis having a top part and a leg part, the top part and the leg part having a top part knit thread and leg part knit thread, respectively, defining a network of knitted meshes, and a top part weft thread and leg part weft thread, respectively, each weft thread having a core which is covered by means of a covering thread, the orthosis being characterized in that the core of the top part weft thread and the covering thread of the top part weft thread are made of elastane, and the core of the top part weft thread has a linear density of less than 0.7 times that of the core of the leg part weft thread.

2. Orthosis according to claim 1, the core of the top part weft thread being double-covered by means of a covering thread of elastane.

3. Orthosis according to claim 1, the top part knit thread being a single covered thread composed of an elastane core covered with a covering thread of polyamide.

4. Orthosis according to claim 1, the ratio of the linear density of the core of the leg part weft thread to the linear density of the core of the top part weft thread being greater than 2.0.

5. Orthosis according to claim 1, the linear density of the core of the leg part knit thread being below 45 dTex and over 10 dTex.

6. Orthosis according to claim 1, the top part having a reinforcement thread, which is different from the top part weft thread and from the top part knit thread, the reinforcement thread having an elongation at break, measured according to norm DIN 53834, of below 40%.

7. Orthosis according to claim 6, the reinforcement thread being made of polyamide and having a linear density of over 30 dTex and below 60 dTex.

8. Orthosis according to claim 6, the top part having an inner cuff and an outer cuff folded back on the inner cuff, the reinforcement thread extending exclusively in the inner cuff.

9. Elastic venous compression orthosis according to claim 1, of class I, II, III or IV, according to the ASQUAL system.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) Other features and advantages of the invention will become clearer from reading the following detailed description and from examining the attached drawing, in which:

(2) FIG. 1 is a schematic representation of an orthosis according to the invention;

(3) FIG. 2 shows the orthosis from FIG. 1 fitted on a lower limb of a patient (position of use);

(4) FIGS. 3a and 3b show a macroscopic view of a detail of the top part and of the leg part, respectively, of the orthosis from FIG. 1;

(5) FIG. 4 is a schematic representation of a detail of a double-covered thread.

DEFINITIONS

(6) Altitude corresponds to a level in the vertical direction V when the orthosis is being worn by a patient standing straight and upright, as is shown in FIG. 2.

DETAILED DESCRIPTION

(7) In FIGS. 1 and 2, reference sign 10 generally designates an orthosis according to the invention.

(8) The orthosis 10, having a general anatomical shape, comprises a foot part 12 enclosing the foot, a leg part 13 having an ankle part 14 enclosing the ankle and a calf part 16 enclosing the calf, and a knitted end part called the top part 18.

(9) The orthosis 10 extends to a level situated below the knee, in the case where the orthosis is a half-hose (or knee sock).

(10) The configuration in the form of a sock is not limiting, and the orthosis 10 may also be produced in the form of a thigh stocking, continued by a compressive thigh part 20. The orthosis 10 may also be produced in the form of tights and/or without a foot part 12 (stocking or tights of the open foot type).

(11) The various adjoining parts of the orthosis 10 are preferably knitted continuously on a circular machine, according to conventional methods. The production of the orthosis 10 does not require any preparatory step for assembling the various parts, except for the operations of sewing on the foot part 12, if the latter is present.

(12) In FIG. 2, the altitudes of the lower limb as defined by the morphological reference system indicated in the introduction (leg model or Hohenstein jig) have been shown using standard notation: B: ankle, at the point of its smallest circumference; B1: junction between the Achilles tendon and the calf muscles; C: calf, at the point of its greatest circumference; D: just below the tibial tuberosity (that is to say just below the knee); E: at the centre of the knee cap and above the back of the knee (that is to say at the level of the popliteal fosse); F: at the middle of the thigh; and G: at the top of the thigh.

(13) The calf is the limb segment situated between levels B1 and D, and the ankle is the limb segment situated below level B1.

(14) As is shown in FIG. 3, the top part 18 conventionally has a network of meshes 22 produced by means of a top part knit thread 24, a top part weft thread 26 being interlaced between said meshes.

(15) The leg part 13 also conventionally has a network of meshes 32 produced by means of a leg part knit thread 34, a leg part weft thread 36 being interlaced between said meshes.

(16) The nature of the threads and of the meshes is adapted depending on the desired action for the different parts of the orthosis, in particular depending on whether the action is to be one of retention or compression. This adaptation does not pose any particular difficulty to a person skilled in the art.

(17) For an elastic venous compression orthosis, the pressure measured at the ankle may in particular vary from 10 to over 36 mmHg (i.e. 13 to 48 hPa, although mmHg is commonly used as the unit of measurement of pressure in the field of phlebology and of medical compression).

(18) The elastic venous compression orthoses are divided into four textile classes according to the ASQUAL system, from class I (13 to 20 hPa10 to 15 mmHg at the ankle) to class IV (>48 hPa>36 mmHg at the ankle).

(19) A weft thread conventionally extends transversely with respect to the principal axis X of the orthosis, shown in FIG. 1. More precisely, it extends orthoradially, spiralling about the principal axis of the orthosis and passing along the rows of meshes.

(20) Top Part

(21) Preferably, the top part 18 is a so-called double cuff structure, that is to say the result of the orthosis neck (which defines the opening through which the orthosis is put on) being folded over inwards or preferably outwards from the orthosis. It thus has an inner cuff 18.sub.i intended to be in contact with the skin of the lower limb of the patient, and an outer cuff 18.sub.e exposed to the outside and separated from the skin by the inner cuff.

(22) In a preferred embodiment, the top part knit thread 24 is a single covered thread composed of an elastane core A covered with one or more covering threads C of polyamide (see FIG. 4).

(23) Preferably, the linear density of the core of the top part knit thread 24 is below 45 dTex, preferably below 30 dTex, preferably below 25 dTex, preferably below 20 dTex, and/or above 10 dTex, preferably above 15 dTex.

(24) Preferably, the linear density of the covering thread of the top part knit thread 24 is below 60 dTex, preferably below 50 dTex, preferably below 45 dTex, and/or above 20 dTex, preferably above 30 dTex, preferably above 40 dTex.

(25) In one embodiment, the top part has only a single weft thread.

(26) In a preferred embodiment, the top part weft thread 26 is a covered thread, preferably a double-covered thread.

(27) The top part weft thread 26 is composed of a core of elastane covered with an elastane covering thread, preferably double-covered with one or more elastane covering threads. The double covering of elastane facilitates the knitting of the orthosis.

(28) Preferably, all the covering thread of top part weft thread 26 are made of elastane.

(29) Without being bound by this theory, the inventors consider that the elasticity of the covering thread prevents the covering thread from limiting the capacities of elastic deformation of the weft thread.

(30) Advantageously, a top part weft thread 26 composed of an elastane core double-covered with an elastane covering thread may be used like the conventional weft threads, without a specific unwinding system, in contrast in particular to simple threads of elastane.

(31) Preferably, the linear density of the core of the top part weft thread 26 is below 150 dTex, preferably below 140 dTex, preferably below 135 dTex, and/or above 100 dTex, preferably above 110 dTex, preferably above 120 dTex, preferably above 125 dTex.

(32) Preferably, the linear density of the covering thread of the top part weft thread 26 is below 40 dTex, preferably below 30 dTex, preferably below 25 dTex, and/or above 10 dTex, preferably above 15 dTex, preferably above 20 dTex.

(33) In a preferred embodiment, the top part moreover has a reinforcement thread 40, which is different from the weft thread and from the knit thread and which extends transversely, like the weft thread.

(34) In one embodiment, the top part has only a single reinforcement thread.

(35) Preferably, the reinforcement thread does not extend over a thigh part and/or an ankle part and/or a calf part and/or a foot part that are intended to enclose a thigh, an ankle, a calf and a foot, respectively, of a patient wearing the orthosis.

(36) Preferably, the reinforcement thread extends exclusively in the top part, preferably over more than 90%, preferably over substantially 100% of the height of the top part. Advantageously, the presence of the reinforcement thread in the top part alone does not modify the behaviour, in particular the elasticity, of the parts of the orthosis that extend below the top part.

(37) Preferably, the reinforcement thread 40 only extends in the inner cuff 18.sub.i of the top part. Comfort is thereby improved.

(38) Preferably, the reinforcement thread 40 has an elongation at break of below 40%, preferably of below 35%, preferably of below 30%, preferably of below 28%, preferably of below 27%. The elongation at break may be measured according to DIN 53834.

(39) The reinforcement thread 40 is preferably of polyamide. Preferably, the reinforcement thread 40 is a simple thread, i.e. not covered.

(40) It preferably has a linear density of over 30 dTex, preferably of over 35 dTex, preferably of over 40 dTex and/or below 60 dTex, preferably below 50 dTex, more preferably below 45 dTex.

(41) The inventors have found that the presence of such a reinforcement thread very substantially improves the resistance to folds in the top part, without impairing the comfort. Now the folds are high-pressure zones which impair the effectiveness of the orthosis.

(42) Leg Part

(43) The leg part knit thread may be identical or different depending on the portion of the leg part in question. In particular, it may be different in the ankle part 14 and calf part 16.

(44) The knit thread may be identical in the calf part 16 and thigh part 20, and/or in the ankle part 14 and thigh part 20.

(45) In one embodiment, the leg part has only a single knit thread.

(46) In a preferred embodiment, the leg part knit thread 34 is a single covered thread composed of an elastane core covered with one or more covering threads of polyamide.

(47) Preferably, the linear density of the core of the leg part knit thread 34 is below 45 dTex, preferably below 30 dTex, preferably below 25 dTex, preferably below 20 dTex, and/or over 10 dTex, preferably over 15 dTex.

(48) Preferably, the linear density of the covering thread of the leg part knit thread 34 is below 60 dTex, preferably below 50 dTex, preferably below 45 dTex, and/or over 20 dTex, preferably over 30 dTex, preferably over 40 dTex.

(49) In one embodiment, the leg part has only a single weft thread.

(50) In a preferred embodiment, the leg part weft thread 36 is a double covered thread composed of an elastane core covered with a covering thread of polyamide. Advantageously, such a covering thread makes the orthosis easier to put on.

(51) Preferably, the ratio of the linear density of the core of the leg part weft thread 36 to the linear density of the core of the top part weft thread 26 is over 1.9, preferably over 2.0, preferably over 2.1, preferably over 2.2, preferably over 2.3, and/or below 3.0, preferably below 2.8, preferably below 2.6, preferably below 2.5, preferably below 2.4.

(52) Preferably, the linear density of the core of the leg part weft thread 36 is below 350 dTex, preferably below 340 dTex, and/or over 250 dTex, preferably over 280 dTex, preferably over 290 dTex, preferably over 300 dTex, preferably over 320 dTex.

(53) Preferably, the linear density of the covering thread of the leg part weft thread 36 is below 40 dTex, preferably below 30 dTex, preferably below 25 dTex, and/or over 10 dTex, preferably over 15 dTex, preferably over 20 dTex.

(54) In a preferred embodiment, the leg part has no reinforcement thread, like the top part.

(55) Of course, the invention is not limited to the embodiments described and shown, which are provided for illustrative purposes only.