Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
2112~8~
F.2063
MEDICAL APPLIANCE FOR INTERMITTENTLY
PULSED COMPRESSION OP PROXIMAL JOINTS
AND ADJACENT TISSUE OF THE HUMAN BODY
HACRGROUND OF THE INVENTION
The invention relates to medical devices for
intermittentl~,r pulsed compression of a part of the human
body, specifi<:ally for intermittent compression at or near a
joint, such as a knee, an elbow or a shoulder, in treatment
5 of a painful disorder of tissue circulation at or near the
joint.
It is known from U.S. Patent No. 4,614,180 that impulse
compression, :Locally applied as intermittent pressure pulses
in the plantar region of the foot, is an effective means cf
l0 enhancing venous-return of blood to the heart. This
technique is an artificial substitute for the action of
weight-bearing, in alternation between one foot and the
other, in the course of walking, for a healthy person, by
reason of body weight flattening the plantar arch, i.e.,
15 transiently spreading the ball and heel of the foot slightly
apart, with concomitant stretching and necking-down of the
veins in the plantar region. For the patient who is unable
to walk and who may have a thrombotic condition with
accompanying pain, the artificially induced intermittent
20 compression o1: the plantar region has been found to provide
the patient with a highly effective means of assuring venous
return, of such therapeutic value as to bring welcome relief
from pain, as well as to reduce swelling and, in many cases,
to eliminate t:he thrombotic condition. U.S. Patent No.
25 4,721,101 describes an extension of the same concept, with
slight modification, indicating that such action on the
plantar veins can also be effective in enhancement of
arterial flow in the involved limb.
Impulse compression devices of the character indicated
30 rely on the facts (i) that veins of the plantar complex
provide a reservoir of accumulated and accumulating blood,
and (ii) that the venous system is characterized by check
valves to assure against back flow of blood that must be
returned to tk-,e heart in the course of healthy circulation.
35 The reservoir veins are squeezed to force blood return via
2~1288~
the one-way return system of check valves, for each
compressional action on the plantar ~reins. A suitable
inactive period of about v0 seconds allows the plantar veins
to swell with a new charge of blood, to be returned by the
5 next compressive actuation at the plantar region.
BRIEF STATEMENT OF THE INVENTION
The present invention is by the same inventors and
derives from their discovery that impulse compression, of
much the same nature as delivered to blood-laden plantar
l0 veins, also has therapeutic value of different kind in
application to proximal joints, in treatment of painful
disorders of tissue circulation at or near the joint. So-
called "tennis elbow" is merely an example of such a
disorder, for there are many and various causes of pain at
15 commonly afflicted proximal joints, such as the elbow, the
knee (e.g., "knee effusions") and the shoulder (e.g., so-
called "frozen shoulder"). Plainly, the action is not one
of intermittently pulsed compression of a reservoir of
accumulating blood; an adequate theory has yet to fully
20 explain the precise mechanics of pulsed compression at or
near such proximal joints, but the pressure pulses, at
intervals of <~t least 15 seconds between pulses, are known
to be effective in reduction of pain and swelling.
Currently, the' mode of action is believed to be one of
25 locally increasing the blood supply i.n capillaries of
compressively activated tissue, where veins accompany
arteries on a microscale, an arrangement that would enable
feedback by connective transport of EDRF1, consistent with
the reported findings of Ley, Tigno, Pries and Geahtgens in
30 their paper, "Blood Flow Regulation in Microvascular
Networks: Role: Of Venolo-arterial Communication", Int. J.
Microcirc, Vo7.. B:Supp1 1:46 (1989).
It is an object of the invention to provide a medical
appliance for intermittent compressive excitation of body
35 tissue in the region of a proximal joint, in relief of pain
and/or swelling at or near the joint.
Another object is to achieve the above object with
relatively simple apparatus, usable by relatively unskilled
Endothelial Derived Relaxing Factor, with accompanying
40 local release of nitric oxide, having a half-life of
about 9 seconds.
- 2 -
X112882
personnel, and in part using an available source of
impulsing energy and action.
The invention achieves the foregoing objects by
providing a sleeve or wrap of an involved joint, including
S distal and proximal limb structure adjacent the joint,
wherein the sleeve has certain features of relative
flexibility and retains an inflatable bag near the joint. A
relatively non-stretch circumferential tie surrounds the
sleeve and is, at least in part, in register with the
10 retained flexible bag. Apparatus is provided for rapid
transient inflation of the bag, followed by relaxation for a
period of at least 15 seconds prior to initiation of the
next such pulsed inflation. Various forms of sleeve or wrap
are described, as are also various forms of inflatable bag.
15 BRIEF DESCRIPTION OF TH~F. DRAWINGS
The invention will be described in detail in
conjunction with the accompanying drawings, which show, for
illustrative purposes only, various embodiments of the
invention. Ln said drawings:
20 Fig. 1 is a simplified view in side elevation, showing
a leg, to the knee region of which an impulse-compression
device of the invention has been applied;
Fig. lA is a view similar to Fig. 1, showing an
appliance of the invention fitted for treatment of a tennis-
25 elbow or the Like condition;
Fig. 2 is an enlarged and simplified cross-section
taken at 2-2 in Fig. 1, for preferred embodiment;
Fig. 2A .is a view similar to Fig. 2 for another
embodiment;
30 Fig. 3 is a greatly enlarged, fragmentary sectional
view of sleevf=_ or wrap material used in the invention;
Fig. 4 is a flattened plan view of sleeve-wrap material
of Fig. 2;
Fig. 5 is an enlarged fragmentary detail of the plan
35 view of Fig. ~!;
Fig. 6 is a view of a circumferential-tie component of
Fig. 1;
Figs. 7A, 7B, 7C and 7D are plan views of alternative
inflatable bags for optional use in the device of Fig. 1;
40 and
- 3 -
21I2882
Fig. 8 i~~ a simplified view in F:~=_rspective showing a
wrap of the invention with provision for impulse compression
therapy for treatment of a frozen-shoulder condition.
DETAILED DESCRIPTION
5 In Fig. 1, the invention is shown in application to a
knee joint, for which a heavy dot 10 will be understood to
indicate the axis of flexion and extension between the
distal limb or calf 11 and the proximal limb or thigh 12. A
sleeve 14 is shown circumferentially enveloping not only the
10 joint per se but also adjacent regions of both the distal
limb 11 and the proximal limb 12. An inflatable bag 15 (see
Fig. 2) is held by sleeve 14 in wrapped conformance to the
adjacent limb (12). In Fig. 2, sleeve 14 is shown in its
preferred form; as a circumferential wrap from initially flat
15 material, with overlapping ends 16, 16' which are adjustab:Ly
and detachably secured at 17, as by engaging surfaces of
hook material and loop material; in the alternative of Fig.
2A, sleeve 14' is circumferentially continuous and
sufficiently stretchable for manipulated placement over the
20 knee as shown. The inflatable bag extends for an angularly
limited range of the circumference of the limb, and as shown
in Fig. 1, a belt or strap 18 wraps the sleeve, to complete
a circumferential tie at a location in overlapping
registration with the inflatable bag; thus, in Fig. 1, only
25 a flexible tubular member 19, for supply of pulsed inlet
inflation air, is exposed from beneath the adjacent proximal
end of sleeve 14.
In applying the sleeve 14 and its retained inflatable
bag to the knee region of Fig. 1, it is generally
30 recommended that a soft cloth or stockinette layer (not
shown) be first applied, to permit a measure of ventilation
of skin surfaces and to prevent local chafing from pulsed
inflation of bag. The bag 15 may comprise two like panels
of flexible plastic material, peripherally welded to each
35 other, and including the flexible inlet member 19; a
preference is indicated that at least one of the bag panels
shall be puncturable, so that the punctured panel can be a
source of cooling air flow, for greater comfort of the
patient. In t:he event of a stockinette wrap, it is
40 convenient first to locate the bag where desired on the
stockinette, as by use of double-stick tape, and then to
- 4 -
CA 02112882 2004-03-09
75361-29
apply sleeve 14 and the circumferential tie 18, in the
indicated lapping register. In particular, it is
recommended that bag 15 and tie 18 be at offset from the
bony prominence or patella (knee cap) 20 of the joint, yet
otherwise in proximity to the region of axis 10.
To serve the purposes of patient comfort in the
course of using the invention, the sleeve 14 (or 14') is
specially characterized for relative stretchability in the
circumferential direction and for relative unstretchability
in the longitudinal direction of the limbs 11, 12 to which
the sleeve is applied. This relation of directional elastic
properties accords with teachings of Figs. 2 and 4 of U.S.
patent 5,267,953, issued on December 7, 1993. The
particular structure to achieve such a relationship in
sleeve 14 will be described in connection with Figs. 3, 4
and 5; it suffices at this point to identify in Fig. 1
circumferentially spaced rows of longitudinally extending
slits, wherein the slits of adjacent rows are in
longitudinally staggered relation.
In use of the invention, when the appliance of
Fig. 2 has been secured as described, a pump apparatus 21
connected to inlet 19 is operated to supply bag-inflating
pulses of compressed air, at intervals of at least 15
seconds. Each inflation is rapidly delivered, in one second
or less, and to a peak pressure of at least 75-mm Hg, to
thereby cause bag 15 to react within the confines of the
circumferential tie 18, for delivery of a concomitant
pressure pulse to microcirculatory structure of tissue
adjacent the knee joint. The commercially available pump
apparatus supplied by Novamedix, Ltd. of Andover, Hampshire,
-5-
CA 02112882 2004-03-09
75361-29
England, for operation of their so-called AVI foot-pump
system is well suited to present purposes at 21 and
therefore need not be described in detail. It suffices here
to state that a range of bag-inflation peak pressures is
selectively available up to pressures in excess of
200-mm Hg, that the rise to peak pressure can be and is
preferably rapidly deliverable in 0.5 second or less, and
that the interval between successive pulses is selectively
available over a range up to 60 seconds, with 20 seconds
being preferred. Further, the commercial Novamedix pumping
apparatus provides for selective control of a period up to
six seconds during which
-5a-
2112882
peak or substantially peak pressure r:pan be retained, prior
to rapid deflation of bag 15. Limits of the indicated
available ranges of pulsed inflation of bag 14 have not as
yet been ascertained but present preferences have in general
5 been stated.
Directing attention to Figs. 3, 4 and 5, the
construction ~~f sleeve 14 (14') is seen to comprise
laminations to a central sheet 23 of flexible elastomeric
material, wherein an inner lamination 24 of woven fabric is
l0 of smooth and soft finish, for patient comfort, and an outer
lamination 25 is of such relatively coarse weave as to be to
a degree engageable by commercially available hook material,
as for example that material known under the mark Velcro.
The material of sleeve 14 is thus a flexible laminated
15 sandwich, having a profile in flattened condition as shown
in Fig. 4. This profile may be described as generally
rectangular, or more accurately as generally trapezoidal,
wherein a distal edge or margin 26 is of shorter extent D1
than a proximal edge or margin 27 of greater extent D2. The
20 longitudinal dimension of an installed sleeve 14 is
accounted for as the space between the distal and proximal
edges 26, 27, and the flattened profile of the material of
sleeve 14 is characterized by opposite lateral edges 28, 29
which converge in the distal direction. These lateral edges
25 are designed f:or the lapped engagement described in
connection with Fig. 2, and each of these lateral edges is
centrally recessed at 28', 29', so that there can be
separate circumferential completion of sleeve 14 around the
proximal region of adjacency to the knee, independent of a
30 separate circumferential completion of sleeve 14 around the
distal region of adjacency to the knee. The recesses 28',
29' are of sufficient width and depth to enable relatively
comfortable flexing of the knee, when the recessed regions
between distal and proximal laps 28, 29 of sleeve 14 are
35 located on the concave side of limb flexure at the knee, as
shown in Fig. 1. To enable the circumferentially completing
laps to be self retaining, separate pads 30, 31 of the
indicated hook material are shown along the inner-surface
portions of edge 28, for lap-retaining engagement with the
40 coarsely woven fabric of outer surface lamination 25 of the
composite sleeve material. Alternatively, the outer-surface
- 6 -
2112882
portions of edge 29 may be provided with suitably stitched
pads (not shown) ef loep material compatible with the hook
material of pads 30, 31.
Consistent with the "generally rectangular" and
5 "generally trapezoidal" expressions r_hus far used in
describing the profile of sleeve (14) material, a preference
is indicated that, for cosmetic appearance, the proximal
edge 27 shall be a convex arc and the distal edge 26 shall
be a concave arc, and that both arcs shall be about the same
10 distally remote center 32 and at the respective radii R;, RZ
indicated in Fig. 4 by arcs described with phantom outlines
26', 27'.
To complete a description of sleeve 14, further
reference is made to Fig. 5 wherein r-he above-noted
15 longitudinal'~y slitted nature of sleeve 14 is shown in
illustrative and enlarged detail, a preference being
indicated that such slitting be confined within borders
delineated by heavy phantom outlines 33 in Fig. 4, so as to
establish a peripherally continuous margin 34 outside the
20 outline 33. For convenience, a symbolism is adopted with a
double-headed arrow 35 in Figs. 4 and 5 to display the
directional orientation of all slits in sleeve 14; this
direction will sometimes be referred to as longitudinal,
consistent with the elongate direction of ultimately
25 installed limb directions; the orthogonally related
direction is the direction of relative stretchability,
sometimes referred to as the lateral, or circumferential
direction.
In Fig. 5, slits 36 in odd-numbered row alignments a,
30 b, are equal in length S, to slits 36' in even-numbered rows
a', b', and t:he respective longitudinal spacing S2 between
all slits 36 in the odd-numbered rows is the same as the
spacing between all slits 36' of the odd-numbered rows.
Suitably, slit length S1 may be 10-mm, and slit spacing S2
35 may be in the: range 5 to S-mm, to allow for at least a 1-mm
overlap of both ends of slits of one row, with respect to
slits of the next-adjacent row, for the symmetrically
staggered interlace relation shown. For the preferred slit
dimensions and relations stated, a spacing S, of 3 to 6-mm
40 between adjacent rows is satisfactory, with a preference
stated for ar, S, dimension of 4 to 5-mm. All slits 36 may
_ 7 _
211~8F~~
be knife cuts or narrow punchings through all laminations cf
the material of sleeve 14.
In the diagram of Fig. 5, it is indicated that the
circumferential tie 18 may be a single elongate strip 38 of
hook material wherein the hook material finish is on the
underside 39, for circumferential engageability with the
coarsely woven outer ply of sleeve 1~1, while the outer
surface is relatively smooth, all except for a patch 40 of
loop material, preferably locally stitched or otherwise
secured to the=- smooth outer surface.
Figs. 7A to 7D illustrate various forms of inflatable
pad, to different contours, offering the physician a range
of options to suit what he deems to be a particular
patient's requirement. In all cases, these different pads
comprise two panels of flexible plastic material, to the
same peripher<~1 contour and edge-welded, as suggested by
dashed-line markings adjacent the peripheral contour of the
pad. Also, in all cases a flexible inlet tube 19 provides
sealed communication of pressure pulses to the interior of
the bag. In Fig. 7A, the bag 42 has an arcuate
configuration generally conforming to a horseshoe shape,
wherein the width w may be in the range 40 to 60-mm, and the
arcuate extent. may be sufficient to wrap around the outer
profile of the limb, in encircling but spaced relation to
the bony prominence 20, and with the end regions 43, 43' cf
bag 42 either in register with or near-register with
opposite ends of the axis 10 of knee articulation; such an
arrangement enables delivery of simultaneous and oppositely
directed pulsed compression of the joint on or close to
tissues near axis 10. And more concentrated delivery of
such localized pressure pulses may be enhanced by
distributing a plurality of spaced spot welds 44 of the
involved pane7.s to each other, to points short of the
arcuate limit:; of the bag 42. As with all inflatable bags
(and sleeves 7.4, 14'), actual dimensions will be a function
of the physical dimensions of the involved patient and limbs
connected at t:he involved point.
The inflatable bag 45 of Fig. 7B is of annular
configuration wherein radial width W' may be 50-mm. In this
case, something approximating the horseshoe, or
preferentially arcuate pattern of delivered impact pulses,
- 8 -
2112~8~
is achievable by providing a succ~ssion of local spot welds
46 of the bag panels to each other.
The inflatable bag 47 of Fig. ,_. is of generally
elliptical configuration to enable an entire inflatable bag
5 to be totally lapped by a single circumferential tie 18,
where the width of the tie 18 equals or exceeds the minor-
axis dimension of the ellipse.
The inflatable bag 48 of Fig. 7D is of elongate
rectangular proportions, as for a purpose similar to that
10 expressed for the configuration of Fig. 7C, except that of
course the configuration of Fig. 7D will permit a more
uniform application of pulsed compressional pressure values,
throughout the applicable circumferential extent of the bag.
Fig. lA is a view similar to that of Fig. I, but
15 showing the invention in application to an elbow, to which a
sleeve 14 has been applied, with a circumferential tie 18
applied to a distal-limb location of adjacency to but offset
from the bony prominence 49 (the olecranon) of the elbow.
Except for specific dimensions to accommodate the size of a
20 particular patient's features at and near the elbow, the
description of appliance components and their operation are
as described for the knee-joint situation of Fig. 1.
The configuration of Fig. 8 is a wrap in the form of a
half-jacket 50 of sleeve material as described in connection
25 with Fig. 3. The jacket-like wrap 50 comprises like front
and back panels A, A' of such material, connected by
stitched seams, as at 51, to an upper bridging panel B, on
the directly viewable side of a vertical plane of symmetry,
wherein the said plane is defined by lines 52, 53 in the
30 drawing. It will be seen that panel B is generally arcuate,
extending over the top of a patient's shoulder, and that its
distal end defines the upper arcuate half of the generally
circular openi:ag 54 for admission of the patient's arm; in
Fig. 8, the arrows 52', 53' will be understood to be normals
35 to the vertica:L plane of symmetry which contains line 52 at
the body end o:E the article 50 and which also contains line
53 through central points at upper and lower limits of the
arm-hole opening 54. Further, it will be understood that
seam 51 has its image at a like seam cf panels A' and B to
40 each other, but. that this image location of another seam
does not appear in Fig. 8, so as not to unduly complicate
- 9 -
2112882
the drawing. A fourth panel C of the same material of Ficx.
3 is a body-side panel that is stitched along seam 55 to -
panel A, and panel C is similarly stitched along a
corresponding seam (not shown) to the back panel A'. The
5 body-side panel C is also stitched along seam 56 to the
upper bridging panel B, as well as along a corresponding
seam connection (not shown) to the ether side of the upper
bridging panel B. And with these two seam connections (at
56, and at the image location thereof), panel C completes
l0 the circular opening 54 for arm insertion. Double-headed
arrows 57 on panel A, 57' on panel A', 58 on panel B, and 59
on panel C will be understood to express the longitudinal
direction of the slit pattern described in connection with
Fig. 5. Thus, around the opening for passage of the
15 patient's arm, the primary stretchable orientation is one of
circumferential continuity. And at wrap of the involved
half of the patient's chest or torso, the primary
stretchability is circumferential, for the extent of torso
engagement.
20 With the jacket-like wrap 50 and on an alignment 60 of
pulsed compressional excitation (available from the means 21
of Figs. 1 and lA), two like inflatable pads 61, 61' are
adhered either to the patient or to the inner surface of
wrap 50. And a suitable strap 62, as described at Fig. 6
25 and of width to substantially overlap both pads 61, 61',
establishes a circumferential tie for the previously
described alignment of simultaneous impulse compression in
the region of adjacency to the shoulder joint, while also at
offset from t:he bony prominence (the acromion) of the joint.
30 A second circumferential tie 63, of more elastic nature as
provided by a strip of elastomeric material having hook-and-
loop end-attachment features (not shown) will provide
assurance of :retained torso envelopment via panels A, C, and
A'.
35 Operation of the arrangement of Fig. 8 is in exact
correspondence to the embodiments of Figs. 1 and lA. The
pulsed compre:asion is applied to microscale capillary
components of the vascular and arterial systems. There is
no single reservoir to receive pumping action, as at the
40 plantar arch, but these multiple capillary components
abound, in the' skin areas adjacent the joint. Not only are
- 10 -
2112882
pain and swel:Ling caused to reduce, but there is now
evidence that blood flow is enhanced in capillaries at the
region of the involved joint.
- 11 -
