TITLE: INTER-SCAPULAR BOLSTER
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority from US provisional application
60/666,764, which is hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to posture support devices and more particularly to posture support devices for use with portable and/or permanent backrests for chairs and seats.
BACKGROUND OF THE INVENTION
[0003] It is generally recognized that poor posture can lead to several painful conditions over time. To assist in preventing poor posture several manufacturers have developed backrests for chairs and seats, which are intended to improve the posture of the user. However, there remains a need for further improvements in backrests to assist the user in maintaining good posture while seated.
SUMMARY OF THE INVENTION
[0004] In a first aspect, the invention is directed to a back support for supporting at least a portion of the back of a user. The back support includes a backrest and an inter-scapular bolster. The backrest has a lumbar support that is shaped to engage the lumbar region of the user and to urge the lumbar spine of the user towards a neutral curve. The inter-scapular bolster has a bolster body. The bolster body is connected to the backrest and is positioned for engaging the user between the scapulae, wherein the bolster body has a bottom that is positioned to engage the user no lower than approximately the lower edge of the T8 vertebra of the user.
[0005] In a second aspect, the invention is directed to an inter-scapular bolster for positioning between the scapulae of a user. The bolster includes a bolster body. The bolster body is connectable to a backrest at a support position for engaging the user between the scapulae. The bolster body has a bottom. When the bolster body is in the support position, the bottom of the bolster body is positioned to engage the user no lower than approximately the lower edge of the T8 vertebra of the user.
[0006] In a third aspect, the invention is directed to a back support for supporting at least a portion of the back of a user. The back support includes a backrest and an inter-scapular bolster. The backrest has a lumbar support that is shaped to engage the lumbar region of the user and to urge the lumbar spine of the user towards a neutral curve. The bolster includes a bolster body that is connected to the backrest and is positioned generally for alignment with the centerline of the back of the user. The bolster body is less than approximately 4" wide. The bolster body has a bottom that is positioned to engage the user no lower than approximately the lower edge of the T8 vertebra of the user.
[0007] In a fourth aspect, the invention is directed to an inter-scapular bolster that is positionable at a suitable height with respect to the back of the user, that is sized to fit between the scapulae of the user, and that, in use, urges the shoulder joints of the user rearward and adducts the scapulae.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The present invention will now be described by way of example only with reference to the attached drawings, in which:
[0009] Figure 1a is a perspective view of a person exhibiting good posture, in accordance with the prior art;
[0010] Figure 1b is a rear elevation view of the person shown in Figure
1a;
[0011] Figure 1c is a magnified rear elevation view of a scapula, a clavicle, a humerus and a sternum from the person shown in Figure 1a;
[0012] Figure 1d is a magnified rear elevation view of some of the muscles, neurovascular structures and skeletal structure of the person shown in Figure 1a;
[0013] Figure 1e is a front elevation view of some of the internal musculature on the person shown in Figure 1a;
[0014] Figure 1f is a front elevation view of some of the skeletal structure of the person shown in Figure 1a illustrating the passage of some neurovascular structures through a gap between the clavicle and the first rib;
[0015] Figure 2a is a rear elevation view of person shown in Figure 1a, showing abduction of the scapulae resulting from poor posture;
[0016] Figure 2b is a front elevation view of the skeletal structure shown in Figure 1f illustrating the compression of some neurovascular structures between the clavicle and the first rib;
[0017] Figure 3 is a perspective view of a back support for supporting a user in accordance with an embodiment of the present invention whereby the back support includes a backrest and a bolster;
[0018] Figure 3a is a side sectional view of the back support shown in Figure 3, shown supporting a person;
[0019] Figure 3b is a horizontal sectional view of the back support shown in Figure 3;
[0020] Figure 3c is another horizontal sectional view of the back support shown in Figure 3; [0021] Figure 4 is a vertical sectional view of a variant configuration of a portion of the back support shown in Figure 3;
[0022] Figure 5 is a vertical sectional view of a variant configuration of another portion of the back support shown in Figure 3;
[0023] Figure 6 is an exploded perspective view of the back support shown in Figure 3;
[0024] Figure 7 is a rear elevation view of the back support shown in
Figure 3; [0025] Figure 8 is a front elevation view of the back support shown in
Figure 3;
[0026] Figure 9 is a rear elevation view of a bolster body from the back support shown in Figure 3, in relation to the skeletal structure of the user;
[0027] Figure 9a is the rear elevation view of a bolster body from the back support shown in Figure 3, in relation to the skeletal structure of the user;
[0028] Figure 10 is a magnified side view of a bolster body that is part of the back support shown in Figure 3;
[0029] Figure 11 is a magnified front view of the bolster body that is part of the back support shown in Figure 3;
[0030] Figure 12 is a magnified front view of an alternative bolster body that could be used as part of the back support shown in Figure 3;
[0031] Figure 13 is a magnified front view of another alternative bolster body that could be used as part of the back support shown in Figure 3; [0032] Figures 14a is a sectional plan view of the bacc support shown in Figure 3, showing the bolster in engagement with the back of the user, whereby the bolster has a depth that prevents both lateral edges of the user's back to contact the backrest;
[0033] Figures 14b is a sectional plan view of the bacc support shown in Figure 3, showing the bolster in engagement with the back of the user, whereby the bolster has a depth that permits both lateral edges of the user's back to contact the backrest;
[0034] Figure 15 is a perspective view of the back support shown in
Figure 3, illustrating points of contact that occur with the user;
[0035] Figure 16 is a front elevation view of a pump that is part of the bolster shown in Figure 3;
[0036] Figure 17 is a rear elevation view of the bolster body shown in
Figure 6; [0037] Figure 18 is a side view of an alternative bolster body to that which is shown in Figure 10;
[0038] Figures 19-22 are front elevation views of several configurations of bolster bodies each made up of multiple separate elements;
[0039] Figure 23 is a perspective view of a bolster that includes a sleeve for removably attaching the bolster to a backrest, in accordance with another embodiment of the present invention;
[0040] Figure 24 is a perspective view of another bolster that includes another sleeve for removably attaching the bolster to a backrest, in accordance with another embodiment of the present invention; [0041] Figure 25 is a side sectional view of the back support shown in
Figure 3, shown supporting a person reclining at an angle;
[0042] Figure 26 is a perspective view of the bolster shown in Figure 3 on a backrest in accordance with another embodiment of the present invention; and [0043] Figure 27 is a side view of an optional, additional, less-functional portion that may be included as part of the bolster shown in Figure 3.
DETAILED DESCRIPTION OF THE INVENTION
[0044] For purposes of clarity the terms 'circumference' and 'effective circumference' are used herein to refer to the distance around the perimeter of an object or a portion of the human body, even though the object or the body portion may not be perfectly circular.
[0045] Reference is made to Figures 1a and 1b, which show a person
10. The person 10 has a body that includes, among other things, a torso 12,
a head 13, a pair of arms 14 and a pair of shoulders 15. The torso 12 has a front 16 (Figure 1a), a back 18 (Figure 1b) and two sides 20. Skeletal elements that are present in the torso 12 and arms 14 include, among other things, two scapulae 22 (Figure 1b), a spine 24, ribs 26, a sternum 28 (Figure 1a), two clavicles 30 and two humeruses 32.
[0046] Referring to Figure 1c, the scapula 22 and the humerus 32 meet at a joint 34, which is the shoulder joint 34, also known as the glenohumeral joint 34. Each clavicle 30 has a first end 35 and a second end 36. At the first end 35, the clavicle 30 is connected at a joint 38 to the top of the sternum 28. At the second end 36, the clavicle 30 is connected to a region of the scapula 22 called the acromion, shown at 40. The joint between the clavicle 30 and the acromion 40 is referred to as the acromioclavicular joint and is shown at 42.
[0047] The first rib is shown at 26a in Figure 1c, and connects to the sternum 28 just under the clavicle 30. A gap is present between the clavicle 30 and the first rib 26a.
[0048] Referring to Figure 1d, the pectoralis minor muscle, shown at
45, is connected at one end to a pectoralis minor tendon 47, which is itself connected to a portion of the scapula 22 known as the coracoid process, shown at 72. At its other end, the pectoralis minor 45 connects to the third, fourth and fifth ribs, which are shown at 26c, 26d and 26e.
[0049] Referring to figure 1e, the pectoralis major muscle is shown at
74 and extends between the sternum 28, the clavicle 30 and the humerus 32.
[0050] Referring to Figure 1d, several neurovascular structures pass through the gap, passing over first rib 26a and under the clavicles 30. These neurovascular structures are identified at 44, and include the brachial plexus, the subclavian vein, and the subclavian artery. Additionally, the subclavius muscle is present in the gap, and thus occupies some of the space between the clavicle 30 and the first rib 26a.
[0051] Several neurovascular structures pass underneath the pectoralis minor tendon 47, including the brachial plexus and the axillo-subclavian artery and vein. These neurovascular structures are identified at 27.
[0052] Referring to Figures 1a and 1b, the torso 12 has a first position, in which the person 10 can be described as having good posture. When exhibiting good posture, the lumbar and thoracic portions of the spine 24 are together generally S-shaped, curving outwards anteriorly in the lumbar region shown at 24I and curving outwards posteriorly in the thoracic region, shown at 24t. [0053] Referring to Figure 1f, when the person 10 exhibits good posture, sufficient space is present in the gap between the clavicles 30 and the first rib 26a to permit the vascular structures 44 that pass through substantially uncompressed.
[0054] Additionally, referring to Figure 1d, when the person 10 exhibits good posture, sufficient space exists under the pectoralis minor tendon 47 to permit the passage underneath of the neurovascular structures 27 with substantially no compression.
[0055] Referring to Figure 2a, when a person 10 is in a slouched, or round-shouldered, position, numerous ailments can result, including, for example, migraine headaches, blurred vision, facial pressure, tinnitus, neck pain, neck swelling, hand and arm pain, coldness of the hands and/or feet, back pain, groin pain and intermittent numbness.
[0056] In a slouched, or round-shouldered, position, the body, and in particular, the spine 24 no longer has an S-shaped configuration. As a result, pressure is distributed between the vertebrae and the discs of the spine 24 in such a way as to urge the discs to bulge, which can, over time, lead to several problems, which are known to persons skilled in the art.
[0057] A round-shouldered posture may be acquired as a result of lifestyle and/or occupation. For example, in some types of employment, a person 10 uses their pectoral muscles 45 and 74 (Figures 1d and 1e
respectively) predominantly and the periscapular muscles and lumbar extensors are typically neglected, resulting in what is called deconditioning. In a deconditioned state the combined pull of the pectorals 45 and 74 and the failure of the periscapular muscles and lumbar extensors together create a round-shouldered posture.
[0058] As a result of the relatively poorly opposed pull of the pectorals
45 and 74, the scapula 22 becomes abducted, and thus moves outwards laterally, as shown in Figure 2b. The lateral movement of the scapula 22 causes the clavicle 30 to pivot generally in a horizontal plane about the acromioclavicular joint 42, whereby its first, or proximal end 35 is urged rearwardly. This changes the angle of the clavicle 30 in the horizontal plane relative to the first rib 26a, and results in a narrowing of the gap. This, in turn, results in compression of some or all of the neurovascular structures 44 that pass through the gap, such as, for example, the brachial plexus and the subclavian vein. The subclavian artery may be compressed, but this may be less common due to several reasons, one of which is that the wall of the subclavian artery is relatively more rigid than at least some of the other neurovascular structures 44.
[0059] It will be understood that, when compression of the neurovascular structures 44 is said to take place between the clavicle 30 and the first rib 26a, one or both of the clavicle 30 and the first rib 26a might not be in direct contact with the structures 44 that are being compressed. Other elements such as the subclavian muscle or the infraspinatus which are present in the gap may be involved in the compression. [0060] Compression of the neurovascular structures 44 can lead to several of the ailments noted above. For example, as a result of the compression of the vascular structures that are included in the neurovascular structures 44, the resistance to fluid flow in these vascular structures increases, which results in dilation of certain veins and tributaries, and increased arterial vascular resistance due at least in part to the slowed venous flow. The consequences of venous congestion and increased arterial
resistance are well known in the form of edema and ischemia first in the areas of greatest vascular impairment and later in other body regions also. Numerous ailments can result from this condition of compressed neurovascular structures 44, including, for example, migraine headaches, facial pressure, neck pain, hand and arm pain and numbness, coldness of the hands, some forms of non-radicular leg pain and intermittent numbness.
[0061] As a result of its connection with the sternum 28, the rearward movement of the first or proximal end 35 of the clavicle 30 causes the sternum 28 (and in particular, the manubrium sternum) to move rearwardly along with it, thus reducing the distance between the manubrium sternum and the anterior border of the body of T3 (the third thoracic vertebra).
[0062] In certain types of people 10 this reduction in the aforementioned diameter can lead to one or more difficulties. For example, individuals with a thin, narrow thorax tend to have a relatively straight cervical and thoracic spinal, saggital alignment. In such people, a loss of cervical lordosis and flattening of the thoracic kyphosis leads to a closer approximation of the posterior surface of the manubrium sternum to the anterior border of the body of the third thoracic vertebra. For example, in some people this distance may be less than approximately 5 cm (2 inches). With the proximal ends 35 of the clavicles 30 urged rearwardly as described above, this distance may be reduced to approximately 2.5 cm (1 inch) to 3.8 cm (1.5 inches). This is especially true at the head of the first rib 26a which sits deeper into the thorax than the other ribs 26. This positioning of the first rib 26a permits it to compress particular veins, such as the brachiocephalic vein. Other people 10 who may be prone to incurring difficulties from the reduced 'diameter1 include individuals who have pectus excavatum, individuals who have thoracic scoliosis, individuals who have a loss of cervical lordosis in general, and/or individuals who are obese.
[0063] In addition to causing the rotation of the clavicle 30 in the horizontal plane, the movement of the scapula 30 as a result of deconditioning can also cause a rotation of the clavicle 30 generally about its own length in a
clockwise direction from a viewpoint facing the side of the left shoulder of the person 10, and in a counterclockwise direction from a viewpoint facing the side of the right shoulder of the wearer 10. Due to the configuration of the clavicle 30, this rotation further narrows the gap between the clavicle 30 and the first rib 26a, thereby adding to the compression of the neurovascular structures 44 that pass therethrough.
[0064] In addition to the above, deconditioning of the stabilizer muscles of the scapula 22 can also lead to 'non-neurogenic winging1 of the scapula 22. Non-neurogenic winging of the scapula 22 refers to an outward movement of the medial edge of the scapula 22 away from the plane of the back 18, however, it is not caused by damage to the long thoracic nerve, which is the typical cause of neurogenic winging. Non-neurogenic winging is instead the result of the weakened state of the stabilizer muscles that hold the medial edge of the scapula 22 down in the plane of the back 18. [0065] Non-neurogenic winging of the scapula 22 causes a rotary torque to be exerted on the acromioclavicular joint 42, which in turn causes a downward movement of the clavicle 30. This downward movement of the clavicle 30 further reduces the size of the gap, and therefore exacerbates the problem of compression of the neurovascular structures 44 that pass therethrough.
[0066] Additionally, in situations where drooping of the scapula 22 occurs as a result of deconditioning, the coracoid process 43 and, in turn, the pectoralis minor tendon 47 may be lowered relative to their normal position, whereby the pectoralis minor tendon 47 compresses the neurovascular structures 27 that pass underneath. Compression of these structures 27 results in many of the same ailments as compression of the structures 44 that pass underneath the clavicles 30.
[0067] It will be noted that movement of the scapulae 22 can impart movement to the ribs 26 by way of their connection to the ribs 26 through the scapular stabilizer muscles. Abduction of the scapulae 22, as shown in
Figure 2a can urge the fronts of the ribs 26 to turn downwards at their joints
with the sternum 28. This can result in a reduction in the volume of the rib cage, which can add resistance to expansion of the lungs during breathing, thereby hampering breathing.
[0068] Backrests for chairs are available that provide lumbar support, which urges the lumbar portion 241 of the spine 24 towards a neutral curve, thereby generally urging a person towards a more upright sitting position. However, for several reasons, including for example, pectoral predominance that exists in many people, the scapulae 22 remain abducted even when sitting in a chair with lumbar support. [0069] Reference is made to Figure 3, which shows a back support
100, in accordance with a first embodiment of the present invention. The back support 100 includes a backrest 102, an inter-scapular bolster 104 and may optionally include a cover 105. The backrest 102 has a lumbar portion 106 and a thoracic portion 108. [0070] The lumbar portion 106 engages the lumbar portion 24I of the user 10. In a central vertical sectional plane shown in Figure 3a, the lumbar portion 106 preferably is curved outwardly (ie. it is convex) in a forward direction to generally match the neutral curve of the lumbar spine 24I (see Figure 3a) and thereby urges the lumbar spine 24I towards the neutral curve. It is alternatively possible however, for the lumbar portion 106 of the backrest 102 to have some other shape that extends outward in a forward direction that still urges the lumbar spine 24I of the user 10 towards a neutral curve.
[0071] Referring to Figure 3, the lumbar portion 106 may have an apex
110 when viewed in a vertical sectional plane. It is alternatively possible for the lumbar portion 106 of the backrest to be include some straight segments (see Figure 4) instead of being solely made up of a smooth curved surface. In such embodiments, any point along the segment shown at 112 may be considered to be the apex 110.
[0072] Referring to Figure 3b, when the lumbar portion 106 is viewed in a horizontal sectional plane taken at the apex 110, the lumbar portion 106
may be concave when viewed from the front (see Figure 3b). The concavity of the lumbar portion 106 may assist in stabilizing the user 10 in a seated position against the back support 100. The shape of the lumbar portion 106 is discussed in further detail below. [0073] Preferably, the lumbar portion 106 of the backrest 102 is concave when viewed in a horizontal sectional plane at any point throughout the height of the lumbar portion 106 to further assist in stabilizing the user 10 and not just in the horizontal sectional plane shown in Figure 3b.
[0074] Referring to Figure 3a, in the central vertical sectional plane, the thoracic portion 108 preferably is concave when viewed from the front, to generally match the neutral curve of the thoracic portion 24t of the spine 24
(see Figure 3a) and thereby urges the thoracic spine 24t towards the neutral curve. It is alternatively possible however, for the thoracic portion 108 of the backrest 102 to have some other shape that extends inward in a forward direction that still urges the thoracic spine 24t of the user 10 towards a neutral curve.
[0075] Referring to Figure 3, the thoracic portion 108 may have an apex 114. It is alternatively possible for the thoracic portion 108 of the backrest 102 to be include some straight segments (see Figure 5) instead of being solely made up of a smooth curved surface. In such embodiments, any point along the segment shown at 115 may be considered to be the apex 114.
[0076] When viewed in a horizontal sectional plane taken at the apex
114 (Figure 3), the thoracic portion 108 may be generally flat (see Figure 3c). By making the thoracic portion 108 flat along the horizontal sectional plane, the thoracic portion 108 avoids obstructing movement of the arms of the user 10 while seated.
[0077] Preferably, the thoracic portion 108 of the backrest 102 is flat when viewed in a horizontal sectional plane at any point throughout the height of the portion of the thoracic portion 108 that is above the apex 114 to further assist in avoiding obstruction of movement of the arms of the user 10.
[0078] Based on the described possible shapes for the lumbar and thoracic portions 106 and 108, their combined shape in the central vertical sectional plane may be a relatively gentle S-shape (best seen in Figure 3a), which preferably generally matches the neutral curve of the lumbar and thoracic portions 24I and 24t of the spine 24.
[0079] The lumbar and thoracic portions 106 and 108 of the backrest
102 may be similar to the lumbar and thoracic portions of the backrest described in copending US provisional patent application 60/734,273, which is hereby incorporated by reference. [0080] Reference is made to Figure 6. The backrest 102 may include a support member 116 and a cushion layer 117. The support member 116 may be a rigid or semi-rigid piece that is made from any suitable material, such as a suitable polymeric material, such as for example, a medical grade, high impact polystyrene provided by Chi-Mei in Taiwan. Other resiliently flexible materials can be used. For instance polymeric materials such as a polyurethane-based material, a polycarbonate-based material, an ABS-based material, a polypropylene-based material, a fiberglass-type material may be used. Alternatively, other materials such as wood or metallic materials (eg. plywood or steel) may be used. [0081] The cushion layer 117 may be made from any suitable material, such as, for example, egg-crate foam rubber (also referred to as polyurethane foam). The egg-crate foam may, for example, have a total thickness of 28mm with a 10mm base and a 18mm egg crate pattern on top of the base. A density of 34kg/m3 may be used for the foam rubber. [0082] The backrest 102 may be a portable item that mounts to a preexisting chair, so that the backrest 102 may be transported for use on chairs in different locations, such as, for example, a chair at home and a chair at work. In such an embodiment, the backrest 102 may attach to the chair by any suitable means. For example, the backrest 102 may include backrest attachment straps 119 (see Figure 7) which are adjustable in length and which secure the backrest 102 to the preexisting backrest of the chair.
Alternatively, some other means for attaching the backrest 102 to a chair may be provided.
[0083] As an alternative, the backrest 102 may be non-portable, and may itself make up the backrest of a chair. In that case, the backrest 102 need not include attachment straps 119.
[0084] The inter-scapular bolster 104 (Figure 6) has a bolster body 111 that extends outwards from the thoracic portion 108 (Figure 3a) of the backrest 102 and supports the user 10 between the scapulae 22 (best seen in Figure 9). Referring to Figure 3a, by extending outward from the front surface of the backrest 102, the bolster body 111 urges the shoulder joints 34 of the user 10 rearward when the user is seated and has their back 18 pressed against the bolster body 111.
[0085] The bolster body 111 has a top 118 and a bottom 120. The overall length of the bolster body 111 between the top 118 and bottom 120 is shown at L (see Figure 3). Referring to Figure 9, the bottom 120 of the bolster body 111 is positioned sufficiently high on the back support 100 (shown in dashed outline) to engage the back 18 of the user 10 at or preferably above the lower edge of the T8 vertebra, where it has an increased effect in urging the shoulder joints 34 rearward (see arrows 121 in Figure 9a) when the back 18 of the user 10 is pressed thereagainst, and has a reduced likelihood of causing discomfort to the user 10 as a result of pressure on the spine 24, relative to portions of back supports of the prior art that extend outward to engage the user below the T8 vertebra.
[0086] It is optionally possible for the bolster 104 to include a less- functional portion 200 that extends below the T8 vertebra, but that does not extend out sufficiently from the backrest 102 to cause substantial discomfort to the user 10 (see Figure 27). For example, this less-functional portion 200 of the bolster 104 may extend out from the backrest 102 by less than 1" if the bolster body 111 is relatively soft, or by less than 1/2" if the bolster body is relatively firm. In other words, the less-functional portion 200 if present, would not extend out from the backrest 102 enough to cause significant urging of the
user's spine 24 (Figure 3a) away from its position otherwise relative to the backrest 102, or to cause significant discomfort to the user 10. It will be understood that the less-functional portion 200 may be attached to the bolster body 111 and may even be contiguous with the bolster body 111, but is not part of the bolster body 111. It is contemplated that this less-functional portion 200 is likely to be omitted from the bolster 104 in most embodiments.
[0087] By engaging the user 10 at or above the lower edge of the T8 vertebra, the bottom 120 of the bolster body 111 is generally not lower than the bottoms of the scapulae 22, also referred to as the inferior poles of the scapulae 22. The bottoms or inferior poles of the scapulae 22 are shown at 123. A line 122 shows the level of the bottom 120 of the bolster body 111 relative to the bottoms 123 of the scapulae 22.
[0088] More preferably, the bottom 120 of the bolster body 111 is positioned to engage the user 10 approximately at a height that is within the range of the upper 2/3 of the scapulae 22, as shown by the dashed outline of the bolster body 111 in Figure 9a, which further improves the performance of the bolster 104 in urging the shoulder joints 34 of the user 10 rearward during use.
[0089] Referring to Figure 3a, the top 118 of the bolster body 111 is preferably positioned sufficiently low to avoid contacting the user's head 13 and urging the user's head 13 forward, which can cause discomfort to the user 10.
[0090] The bolster body 111 has an overall width W, which is sufficiently small that the sides of the bolster body 111 do not interfere with the adduction of the scapulae 22 when the back of the user 10 is pressed against the bolster body 111 and the user's shoulder joints 34 are urged rearward. Thus, the bolster body 111 fits between the scapulae 22 of the user 10 when the scapulae 22 are in their adducted position as a result of the rearward movement of the shoulder joints 34.
[0091] Referring to Figures 11, 12 and 13, the bolster body 111 may have any suitable shape along its sides, which are shown at 124. For example, referring to Figure 13, the sides 124 may be generally parallel. Alternatively, as shown in Figures 11 and 12, the sides 124 may be generally shaped so that they are less wide than the width W proximate the bottom 120. Referring to Figure 9a, during use of the bolster 104, the scapulae 22 may rotate in such a way that the bottoms 123 of the scapulae 22 rotate medially as the shoulder joints 34 move rearwardly. It is possible that such medial rotation could cause the bottoms 123 of the scapulae 22 to be positioned closer medially than the superior borders of the scapulae, shown at 126. The optional smaller width of the bolster body 111 proximate the bottom 120 provides sufficient clearance to permit the bolster body 111 to avoid interfering with the bottoms 123 of the scapulae 22 during such medial rotation. [0092] The transition from the widest section of the bolster body 111 to the thinner section may have any shape, as shown in the exemplary embodiments in Figures 11 and 12.
[0093] Referring to Figure 10, the depth of the bolster body 111 is shown at D and represents how far the bolster body 111 extends outwards from the plane of the backrest 102. Referring to Figure 14a, the depth D of the bolster body 111 may be sufficiently large that the bolster body 111 acts as a fulcrum against which the back 18 of the user 10 rests. In such an instance, one or both lateral edges of the upper portion of the back 18 of the user 10 would be spaced from the backrest 102. [0094] Referring to Figure 14b, it is alternatively possible for the bolster body 111 to have a depth D that is sufficiently small to permit both lateral edges of the upper portion of the back 18 of the user 10 to be in contact with the backrest 102 at the same time. In such an instance, the bolster body 111 and the lateral edges of the backrest 102 make up three points of contact by the user 10, shown at 128a, 128b and 128c respectively (see Figure 15). The three points of contact 128a, 128b and 128c form a triangle in a generally
horizontal plane and thereby brace the user 10 (the user 10 is not shown in Figure 15) against lateral movement in the event that the user 10 is urged laterally. This resistance to lateral movement can be advantageous in situations where the user is urged laterally. For example, where the user 10 is a bus driver, the user 10 is urged laterally when the bus turns a corner as a result of centrifugal force. The three triangular points of contact 128a, 128b and 128c brace the user 10 against the centrifugal force. This bracing effect can take place even in an embodiment, such as that shown in Figure 14b, where the thoracic portion 108 of the backrest 102 does not have substantial concavity to it when viewed in a horizontal sectional plane. By avoiding a concave shape for the thoracic portion 108 of the backrest 102, the user 10 is not urged into a shoulders-forward position and has relatively more room to move his or her arms while seated than against a backrest with a concave thoracic portion. A shoulders-forward position is less desirable for the user 10 because it would encourage the problems described above for poor posture.
[0095] It will be noted that the internals of the user's body have not been illustrated in Figures 14a and 14b. The outline of the user's body is shown only to illustrate whether contact does or does not occur based on the depth D of the bolster body 111. [0096] It will be understood that the user 10 may contact the back support 100 over some or all of the distances between the points 128a, 128b and 128c in addition to contacting the back support 100 at the points 128a, 128b and 128c. Alternatively, the user 10 may contact the back support 100 over none of the distances between the aforementioned three contact points. [0097] In addition to the horizontal bracing effect that takes place with the three points of contact 128a, 128b and 128c, bracing additionally can occur in the plane of the user's back 18 depending on the shape of the backrest 102. Referring to Figure 15, the lumbar portion 106 of the backrest 102 has lateral edges 128d and 128e. Contact between the body of the user 10 and the back support 100 at the three points 128a, 128d and 128e and may occur over none, some or all of the distances between these points. The
three contact points 128a, 128d and 128e form a triangle in the plane of the user's back 18 (not shown in Figure 15), and thus provide a bracing effect which resists movement of the upper body of the user 10 laterally.
[0098] It will be noted that the bracing effect provided by the triangular shape formed by the contact points 128a, 128d and 128e reduces the need to provide the thoracic portion 108 of the backrest 102 with a substantial concavity to hold the user in place when viewed in a horizontal sectional plane.
[0099] Referring to Figure 3, to fit a range of sizes of users 10, the back support 100 may be provided in several sizes. For example, the back support
100 may include a small size, a medium size and a large size. The small size back support 100 may have a bolster body 111 that is less than or equal to 6 inches long, less than or equal to 3 inches in depth and less than or equal to 3 inches in width. The medium size back support 100 may have a bolster body 111 that is less than or equal to 6.5 inches long, less than or equal to 3.5 inches in depth and less than or equal to 4.5 inches in width. The large size back support 100 may have a bolster body 111 that is less than or equal to 7 inches long, less than or equal to 4 inches in depth and less than or equal to 6 inches in width. Other sizes of back support 100 may be provided in addition to or instead of the sizes listed above.
[00100] Referring to Figure 9, it will be noted that the bolster body 111 need not fill the entirety of the space between the scapulae 22. The effect of the bolster body 111 can be achieved even if the bolster body 111 is only a few inches wide, eg. less than approximately 3.5 - 4 inches wide for people of medium build and even for people of large build.
[00101] Referring to Figure 10, the depth D of the bolster body 111 may vary along its length. For example, the outer face of the bolster body 111, shown at 130, has a curve when viewed in a vertical sectional plane that generally matches the neutral curve of the spine 24 (Figure 3a) so that it urges the spine 24 of the user 10 towards a neutral curve when the user 10 is seated against the bolster body 111.
[00102] Referring to Figure 6, the bolster 104 may be made in any suitable way. For example, the bolster 104 may include an inflatable bladder 132 that makes up the bolster body 111 , a fluid conduit 134, a pump 136 and a release valve 138. The pump 136 is fluidically connected to the bladder 132 by means of the conduit 134. The pump 136 is used to inflate the bladder 132 with a selected amount of fluid, (eg. air) which provides the bolster body 111 with a depth that is selectable based on the amount of fluid contained in the bladder 132.
[00103] Referring to Figure 16, the pump 136 may have any suitable structure. For example, the pump 136 may be manually operable, and may comprise a resilient compressible bulb 140 with a closable air inlet, as is known to persons skilled in the art of manually inflatable devices.
[00104] The release valve 138 may have any suitable structure. For example, the release valve 138 may comprise a threaded cap 142 that covers an air aperture into the fluid conduit 134. When the cap 142 is screwed tightly over the air aperture, it seals against air leakage out from the conduit 134. When the cap 142 is unscrewed, air can escape from the conduit and therefore from the bladder 132, permitting the bladder 132 to be selectively deflated entirely or partially. [00105] Referring to Figure 10, the bladder 132 may also have any suitable structure. For example, the bladder 132 may be formed from two bladder pieces 144a and 144b, which are thermally sealed together at their edges, thereby forming a flange portion 146 about the perimeter of the bladder 132. Referring to Figure 17, tie down apertures 148 may be provided at selected points on the flange portion 146. Straps 150 connect the backrest 102 to the bladder 132 by means of the tie down apertures 148, to secure the bladder 132 in position on the backrest 102.
[00106] As shown in Figure 10, the two bladder pieces 144a and 144b may be approximately the same size, such that the seal is formed generally in the middle of the bladder 132. However, in such an embodiment, as the bladder 132 expands, the flange portion 146 moves away from the backrest
102. Thus, the ends of the straps 150 attached at the flange portion 146 are also urged away from the backrest 102. This can detract from the comfort of the back support 100 during use. This can also detract from the appearance of the back support 100 if the cover 105 (Figure 6) is tight-fitting, since the straps 150 (Figure 10) will urge the cover 105 (Figure 6) away from the backrest 102 in the vicinity of the bolster body 111.
[00107] In an alternative construction shown in Figure 18, the first bladder piece 144a, which rests against the backrest 102 is smaller than the second bladder piece 144b. As a result, most or substantially all of the expansion in the bladder 132 takes place in the second bladder piece 144b, and little of it takes place in the first bladder piece 144a. Thus, the flange portion 146 formed around the perimeter of the bladder 132 does not move away from the backrest 102 much during expansion of the bladder 132. This reduces or eliminates the movement of the straps 150 away from the backrest 102 during expansion of the bladder 132.
[00108] Instead of being made inflatable, the bolster body 111 may be made in some other way. For example, the bolster body 111 may be made from a polymeric foam material that is resilient and flexible but which has sufficient rigidity to urge the shoulder joints 34 (Figure 9) rearward when the user's back 18 is pressed thereagainst.
[00109] As another alternative, the bolster body 111 may be made from a plurality of separate elements, as shown in Figures 19, 20, 21 and 22 instead of being made from a single element, as shown in Figure 11. Furthermore, the configuration of the group of separate elements may be any suitable configuration, so long as they do not inhibit the adduction of the scapulae during use.
[00110] Referring to Figure 23, the bolster body 111 may mount to the backrest 102 by any other suitable connection means instead of the straps 150 (Figure 18). In one embodiment, shown in Figure 23, the bolster 104 includes a sleeve 152 which can be mounted onto the backrest 102. The sleeve 152 may be made with a closed top 154. By having a closed top 154,
the bolster body 111 is limited as to how low it can be mounted on the backrest 102. This can therefore prevent the bolster body 111 from being mounted too low, where it will not be as in urging the shoulder joints 34 rearward, and where it can cause discomfort to the user 10. [00111] In an alternative embodiment, shown in Figure 24, however, the sleeve 152 can be provided with an open top 156. This permits the bolster body 111 to be mounted at any selected height on the backrest 102, regardless of the height of the backrest 102.
[00112] The sleeve 152 in either or both of the embodiments shown in Figures 23 and 24, may be made from an elastic material that can grip the backrest 102 by elastic force over a range of shapes and sized of backrest 102, and thereby retain the bolster body 111 at a selected position.
[00113] By providing a bolster 104 with the sleeve 152 (with either an open top such as the top 154 shown in Figure 23 or a closed top such as the top 156 shown in Figure 24), the bolster 104 can be mounted to an existing backrest 102 that was already in possession by the user 10. Thus, the user 10 does not have to purchase the entire back support 100 including the backrest 102 and the bolster 104. The user 10 could purchase the bolster 104 with sleeve 152 thereby potentially reducing the cost of the purchase. Additionally, the bolster 104 with the sleeve 152 is more compact and lighter and thus is more easily transportable than a portable back support 100 having the bolster 104 and backrest 102. Additionally, the sleeve 152 permits the bolster 104 to be mounted to a backrest 102 that is non-portable (ie. a backrest 102 that is part of a chair 158). [00114] Referring to Figure 24, the sleeve 152 could alternatively include bolster attachment straps 157 to assist in attaching the bolster body 111 to the backrest 102. In embodiments wherein the backrest 102 is a portable device that is placed against a permanent backrest on a chair 158, the bolster attachment straps 157 could also be used to wrap around both the backrest 102 and the permanent backrest of the chair 158. This particular configuration is not shown in Figure 24, since Figure 24 does not show a
portable backrest 102, but instead shows a backrest 102 that is part of the chair 158.
[00115] When the user 10 is seated against the back support 100 it may be advantageous for the back support 100 to be angled back by some angle Th, which may be, for example, approximately 10 degrees (see Figure 25) relative to the vertical. When the back support 10 is angled thus, the downward force exerted by the weight of the body of the user 10, urges the user 10 into the back support 100 and against the bolster body 111, whereas if the back support 100 were completely upright, the force of engagement between the user 10 and the bolster body 111 would be expected to come largely from the user 10 urging himself or herself back into the back support 100, which may be difficult in some situations, such as with an office chair with wheels, for example. However, the back support 100 is in any case contemplated to be effective and useful even in an embodiment wherein it is upright in an office chair with wheels, where it is not as easy to generate a force between the user 10 and the bolster body 111.
[00116] Referring to Figure 6, the cover 105 may be made any suitable way, such as, by two cover pieces 105a and 105b which are joined along a peripheral seam. The cover 105 may be made from any suitable material, such as a breathable and washable material.
[00117] The rearward movement of the shoulder joint 34 (Figure 9a) urges rotation of the clavicle 30 in the horizontal plane about the acromioclavicular joint 42, such that the first, or medial end 35 of the clavicle 30 is urged anteriorly. This movement of the clavicle 30 opens the gap between it and the first rib 26a, thereby reducing or possibly eliminating any compression taking place of the neurovascular structures 44 (Figure 1f) that pass therethrough.
[00118] Additionally, the movement of the clavicles 30 moves the manubrium sternum forward (anteriorly) increasing the distance, or 'diameter' between the manubrium sternum and the anterior border of the body of T3
(the third thoracic vertebra), thereby alleviating (at least in some individuals) compression of certain veins, such as the brachiocephalic vein.
[00119] Additionally, the rearward movement of the shoulder joint 34 and any medial movement of the shoulder joint 34 adducts the scapula 22 (moves the scapula 22 medially). The movement of the scapula 22 medially, rotates the clavicle 30 about its own axis in a direction that is clockwise from a viewpoint facing the side of the right shoulder of the wearer 10 and counterclockwise from a viewpoint facing the side of the right shoulder of the wearer 10. [00120] Additionally, the resulting medial movement of the scapula 22 elevates the pectoralis minor tendon 47 (Figure 1d), reducing any compression that may take place on the neurovascular structures 27 (Figure 1d) that pass underneath.
[00121] Additionally, the rearward movement of the shoulders 15 urges the spine 24 of the wearer 10 towards its neutral position, shown in Figure 1a. As a result, pressure is redistributed between the vertebrae and the discs of the spine 24 in such a way as to reduce any bulging of the discs.
[00122] As a result of the above effects, the back support 100 and the presence of the bolster 104 can be effective in reducing ailments associated with neurovascular compression that has been described above in relation to poor posture and deconditioning. For example, use of the bolster 104 and back support 100 can be effective in reducing migraine headaches associated with poor posture and deconditioning.
[00123] The benefits provided by the back support 100 or bolster 104 shown and described herein may not exist for every individual. However, some individuals will receive at least some of the benefits of the back support 100 or bolster 104.
[00124] Referring to Figure 26, it will be appreciated that it is less important for the thoracic portion 108 of the backrest 102 to have a curve that generally matches the neutral curve of the spine 24. Benefit is obtained
through the use of the bolster 104 even if the thoracic portion 108 of the backrest 102 is uncurved, since the presence of the bolster 104 causes the rearward urging of the shoulder joints 34 and the consequent adduction of the scapulae 22. [00125] In the embodiment shown in Figure 24, the bolster 104 provides some benefit to the user 10 by urging the shoulder joints 34 rearward and adducting the scapulae 22 even with a backrest 102 that has a lumbar portion 106 that is straight and therefore does not generally match the neutral curve of the spine 24. [00126] While the above description constitutes the preferred embodiments, it will be appreciated that the present invention is susceptible to modification and change without departing from the fair meaning of the accompanying claims.