CA2543217C

CA2543217C - Pressure off knee brace

Info

Publication number: CA2543217C
Application number: CA 2543217
Authority: CA
Inventors: Moslem Rezazadeh
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-05-01
Filing date: 2006-05-01
Publication date: 2008-10-07
Anticipated expiration: 2026-05-01
Also published as: CA2543217A1

Abstract

This leg brace is comprised of durable plastic material (used in its structural columns) and cotton material (used in its thigh and calf strap) to permit for a safer, lighter, and more comfortable brace. The structural design of this brace makes it multifunctional such that it is able to support the function of the thigh and the leg muscles, the knee cartilage, the kneecap, the foot and the arch of the foot. The pressure from the person's body weight and that extending from the lower legs and the feet are transferred to the hinges of the brace that help in taking off the pressure from the injured joints and reduce approximately 25% of the pressure from the entire the knee cartilage. This will then allow persons with weak leg muscles to stand up with ease and or climb steps.
The thigh and the calf strap of this brace allow for the uniform and accurate distribution of the weight pressure exerting onto the thigh and calf muscles. The lower structure of the brace allows it to easily glide into the footwear and takes pressure off the ankle.

Description

1 Technical Field:

2 This invention relates to an orthotic leg brace to help persons with injury to the knee, the ankle, and 3 other areas of the leg.

Background of the Invention:
6 Currently, there are many variants of leg braces in the market that claim to help persons with 7 (specific or multiple) problems related to the mechanical condition of their knees or ankles (e.g., 8 orthopedic apparatus, leg brace, knee brace, knee joint orthosis, adjustable orthosis). These orthotic 9 braces may appear to have advantages, however, a closer look at their structural design reveals several major disadvantages. First, they are only capable of taking the pressure off the injured 11 spot(s), whereas my invention takes the pressure off the injured spot(s) and the whole knee cartilage.
12 Second, they fail to uniformly capture a person's body weight and the pressure exerted upward from 13 the feet and the lower legs. There are two reasons for this: 1) the thigh strap in these orthotic leg 14 braces only covers a small portion of the thigh and thus, lacks the mechanical structure to capture the weight and pressure exerted onto the thigh muscles; 2) these leg braces use Velcro straps or laces to 16 close and tighten the thigh strap. Such strap can either close too loosely and fail to fully capture the 17 exerted body pressure or close too tightly and results in muscle pain.
Another disadvantage is that 18 that most are made from metal or aluminum material that can be hazardous during an accident if 19 punctured into the skin. Furthermore, many use plastic and synthetic material in the design of the thigh and shin strap, which can cause the accumulation of heat and sweat and generate odor. Heat 21 and sweat can irritate the skin and cause much discomfort.

23 Summary of the Invention:
24 There are specific features to my multifunctional orthotic brace that performs appropriate mechanical actions to solve specific health issues related to the knee, ankle, and other areas of the 26 leg. This brace addresses what is currently lacking in the market. The features of my invented leg 27 brace are outlined below.

29 A unique and important feature of this leg brace is the thigh strap as it is designed with specific features to uniformly capture the pressure exerted upward from the foot and the lower leg. For 31 example, the thigh strap fits snug over the entire thigh area and the use of zipper in the thigh strap 32 provides for accurate fitting, which then allows for uniform distribution of the pressure extending 33 upwards from the lower legs. During walking, patients with knee or joint pain are unable to keep 34 their leg in a straight posture and have a tendency to bend their knee forward as they walk. This leg 35 brace is able to support and align the patient's leg in a straight posture, especially when the knee tilts 36 inward due to pain. This is achieved by designing either the inner or the outer upper pocket of the 37 thigh strap (into which the skeletal structure of the brace is inserted) to fit shorter. For patients 38 whose inner-knee cartilage has been injured, the pocket of the thigh strap on the inner upper portion 39 is made to fit 30 mm shorter than the outer upper pocket. Similarly, the pocket of the thigh strap on 40 the outer upper portion is made 30 mm shorter as compared to the inner thigh pocket for patients 41 whose outer knee cartilage has been injured. This unique technique allows the pressure to be 42 relieved from the injured spot of the joint and transferred to the hinges of the leg apparatus. This 43 mechanical design helps align the leg in a straight posture.

45 In addition, the skeletal structure of this leg brace is designed to fit 25 mm longer than the leg of the 46 patient. Through this method, the thigh muscle contracts as the person's foot rests on the ground and 47 the pressure is transferred onto the hinges of the apparatus and then onto the thigh muscles. This 48 allows approximately 25 % of the body weight to be absorbed by the thigh muscles. This specific 49 technique acts similarly to crutches in that the longer length of the skeletal structure is what allows 50 the pressure (from the body and the lower legs) to be pushed upward and absorbed by the thigh 51 muscles (this is similar to how a crutch transfers the weight to the muscle of the arms).

53 My invented brace has a stretchable elastic component that acts similarly to a muscle in keeping the 54 leg in a straight posture at all times during walking. An important function of the elastic component 55 is to reduce approximately 8 Kg of the body weight to help patients with weak or injured muscles to 56 stand up or climb steps with ease. It is anticipated that this particular technique will be able to reduce 57 up to 50 % of the body weight in persons who have weakness in their muscles and allow them to 58 carry an extra 25 kg of weight without feeling pain in their joints. While other leg braces in the 59 market have attempted to use such principle to reduce or redistribute the body weight, the 60 mechanisms used in my invention reduce the overall weight of the brace, and are much simpler and 61 more cost effective.

63 Another important feature of my invented leg brace is that it is safe to wear. This is because the 64 flexible plastic material used in the skeletal structure of the brace is wrapped safely in soft, cushiony, 65 non-stretchable cotton material. The use of cotton is specifically used to prevent the accumulation of 66 sweat, heat, odor, and skin irritation.

= CA 02543217 2008-01-08 67 Another important advantage of this brace over others is that patients can wear and remove the brace 68 with ease. For example, this brace can be easily worn under one's clothing (e.g., pants) and remain 69 adjustable at the thigh strap for extra comfort. Also, it can easily attach and detach from all types of 70 footwear as it glides into the ankle part of the apparatus, attached to the side of the footwear making 71 it comfortable when removing the footwear.

73 Brief Description of the Drawings:
74 The following drawings illustrate the embodiments of the invention: Figure 1 is a side elevation 75 view of the leg brace called Pressure Off Knee Brace (P. O.K.B) and is comprised of the Top 76 Subunit, the Cartilage Subunit, and the Bottom Subunit, Figure 2 is a side elevation view of the mini-77 version of the brace and illustrates a smaller version of my brace called the Mini-Pressure Off Knee 78 Brace (Mini-P. O. K. B), and comprises of Units 3 and 4, Figure 3 is a plan view of Unit 2, Figure 4 is 79 a perspective view of Unit 2 of the brace and illustrates the main supporting structure of the brace, 80 Figure 5 is a plan view of Unit 1, Unit 2, and Unit 3, assembled together, and Figure 6 is a side view 81 of the Cartilage Subunit.

83 Detailed Description:
84 The Top Subunit 85 As depicted in Figure 3, the Top Subunit has a width of 40 mm and its length depends on the height 86 of the person. The thickness of this subunit is 4 mm. This subunit consists of a pair. One pair covers 87 the outer leg and the other covers the inner leg. At the end of this subunit is a hole with a diameter of 88 10 mm (refer to point 25 in Figure 3). There is a crescent-shaped hole that sits at a 35-degree angle 89 on this subunit (refer to point 18 in Figure 3). This 35-degree angle allows Unit 2 to bend up to 125 90 degrees. This hole has a width of 6 mm and length of 26 mm (from end-to-end tip). There are two 91 other holes (refer to point 19 in Figure 3) with a diameter of 6 mm. A
durable rubber elastic passes 92 through one hole and is tied into a knot in the other hole.

94 The Cartilage Subunit 95 The purpose of the Cartilage Subunit is to transfer force exerted from the ground upward to the Top 96 Subunit (see Figure 4). A durable rubber elastic sits into a wedge at the side of this subunit (refer to 97 point 29 in Figure 6 to see the side view of this subunit). One tip of this rubber elastic is inserted into 98 point 19a and another tip inserted into point 19b. This rubber elastic serves three purposes: 1) to pull ' CA 02543217 2008-01-08 99 the Top Subunit and the Bottom Subunit to form a straight alignment (at 180 degree); 2) to help a 100 patient with weakness of the leg muscles maintain their leg in a straight posture when standing;
101 3) when the elastic rubber is fully stretched it helps take off approximately 8 Kg of the body weight 102 and transfers it to the hinges of the unit and the thigh muscles. In the future this aids in regaining 103 50% of the function of the leg muscles in patients with weakness in these areas. This subunit acts in 104 a similar manner to the knee cartilage by helping maintain the leg in a straight posture. This subunit 105 has a width of 40 mm, a thickness of 10 mm and length of 80 mm and consists of a pair. One covers 106 the outer leg and the other, the inner leg. There are two holes on this subunit that have a diameter of 107 10 mm each (refer to point 23 and 24 in Figure 3), and two pins mounted at a 35-degree angle on 108 this subunit (refer to point 26 in Figure 3). The thickness of each pin is 6 mm. T'he height of each 109 pin is 4 mm higher than the surface of this subunit. These two pins help the assembly of the Top 110 Subunit, the Cartilage Subunit, and The Bottom Subunit (collectively referred to as Unit 2). The pins 111 further allow the structure to align at a 180-degrees when standing, and bend up to 125-degrees 112 when bending the knee. These two pins, positioned in the crescent shaped opening of the Top and 113 the Bottom Subunits, allow the Cartilage Subunit to act similarly to the kneecap. The purpose of the 114 pins is to prevent the Cartilage Subunit from bending counter clockwise.

116 The Bottom Subunit 117 The Bottom Subunit (see Figure 3 and 4) has a width of 40 mm and the length depends on the height 118 of the person. The thickness of this subunit is 4 mm and consists of a pair. One covers the outer leg 119 and the other covers the inner leg. At one end of this subunit is a hole that has a diameter of 10 mm 120 (refer to point 22 in Figure 3). There is a crescent-shaped hole that sits at a 35-degree angle on this 121 subunit (refer to point 27 in Figure 3). This 35-degree angle allows Unit 2 to bend up to 125-degrees.
122 This hole has a width of 6 mm and length of 26 mm (from end-to-end tip).
There are two other holes 123 that have a diameter of 6 mm (refer to point 28 in Figure 3). A durable elastic rubber passes through 124 one hole and is tied into a knot in the other hole. At the other end (refer to point 11 in Figure 3) of 125 this subunit is a u-shaped opening with a width of 10 mm and a length of 35 mm.

127 Unit 2 128 Figure 4 illustrates the assembly of the Top Subunit, the Cartilage Subunit and the Bottom Subunit 129 together (Unit 2). This unit is the supporting structure of the brace and comes in a pair. The length of 130 this structure is designed 25 mm longer than the leg of the patient in order to mechanically force the 131 weight pressure onto the thigh muscle. In Figure 4, point 20 refers to a cushioned rubber material 132 that is attached to the end of the Top Subunit. The purpose of the cushioned rubber material is to 133 prevent the type of accident. This makes the brace safer to wear. Figure 4 also depicts the rubber 134 elastic (refer to point 7), which extends from the Top Subunit and slides into a wedge that sits on the 135 side of the Cartilage Subunit, and then inserted into the holes of the Bottom Subunit (where it is also 136 secured). The hinges in the Bottom Subunit (point 6 in Figure 4) are composed of a pair of connector 137 bolts and nuts. The connector nut has a height of 14 mm and thickness of 10 mm. The tail of the nut 138 is 3 mm and its diameter is 18 mm. The connector bolt (with a thickness of 6 mm, height of 10 mm, 139 tail thickness of 3 mm and diameter of 18 mm) is inserted into point 23 and 24 in Figure 3 on the 140 Cartilage Subunit and locks into the connector nut on the reverse side.
This creates a hinge that 141 allows the Top Subunit and Bottom Subunit to assemble onto the Cartilage Subunit at point 25 and 142 22, respectively. Point number 17 in Figure 4 shows two pins, previously referred to in the Cartilage 143 Subunit. These pins perform the actions of the kneecap as well as align and lock Unit 2 in a straight 144 position and prevent it from bending counter clockwise. Point 11 in Figure 4 refers to the u-shape 145 opening of the Bottom Subunit, previously referred to in Figure 3. This u-shape opening allows Unit 146 2 to glide into Unit 4. This then allows the brace to act like an ankle or a hinge at point 11 (shown in 147 Figures 1 and 2).

149 Unit 4 150 The structure of Unit 4 is made from strong and durable plastic. This structure is fastened to the 151 footwear at two points on each side. At the top of Unit 4 is a plastic washer (refer to point 10 in 152 Figures 1 and 2). The thickness of the washer is 3 mm and its diameter is 40 mm. In the center of the 153 washer is a hole that has a diameter of 6.5 mm. A 6 mm connector bolt and nut mounts the washer 154 onto the plastic structure of Unit 4. This connector bolt and nut serve as a hinge. This washer 155 prevents Unit 2 from moving side to side when it slides into Unit 4. The assembly of Unit 2 and 156 Unit 4 acts as a hinge and functions like an ankle. The structural design of Unit 4 allows it to 157 function like the ankle.

159 Units 1 and 3(Figure S) 160 In Figure 5, the thigh strap (Unit 1) is made from non-stretchable, cotton material that covers the 161 entire upper and lower thigh. The use of a non-stretchable material will prevent the pockets on the 162 thigh strap from moving back and forth. This will in turn prevent Unit 2 (the structure of the brace) 163 from moving back and forth with each movement of the leg. The cotton material will prevent the 164 accumulation of heat and sweat as it absorbs them. The pockets on the thigh strap are sewn closed 165 (see point 15). For patients whose inner knee cartilage is injured, the pockets that fall in the inner 166 thigh can be sewn closed 30 mm shorter than the pockets that fall on the outer part of the leg (see 167 point 15). This technique will help push the knee outwards, forcing the leg into a straight posture, 168 and take the pressure off the injured spot. For patients whose outer knee cartilage is injured, the 169 pockets that fall toward the outer thigh can be sewn closed 30 mm shorter than the pockets that fall 170 on the inner part of the leg (see point 15). This technique will push the leg inward, forcing the leg 171 into a straight posture, and take the pressure off the injured spot. This also holds true for patients 172 with injury to the ankle. The thigh strap has a zipper that zips from top downward (refer to point 16 173 in Unit 1). The zipper technique allows for accurate fitting, and is used so that when the person is 174 sitting down they can easily unzip the thigh strap to 1/2 or 3/4 of the way to help their muscle rest.
175 In Figure 5, the shin-calf strap, herein refereed to as Unit 3, is made from non-stretchable, cotton 176 material. In Figure 5, Unit 2 passes through the pockets of the shin-calf strap and into the pockets of 177 the thigh strap (see Unit 1). The pockets on the shin-calf strap are not sewn closed at their tips to 178 allow Unit 2 to go through and assemble onto Unit 4. The shin-calf strap closes around the leg with 179 the help of a zipper.

Claims

1. A knee support for relieving compressive stress on a knee when a user is walking on a floor or like surface, wherein the upper unit skeletal structure, adapted to be secured to a user's thigh, and the lower unit skeletal structure, adapted to be secured to the shin and calf portion of the user's leg, together measure 2.5 cm longer than patient's leg, and comprising:
an intermediate cartilage-supporting unit pivotally connected both to the upper unit and the lower unit; and an ankle unit pivotally connected to the lower end of the lower unit and having means for transmitting force from the floor or like surface to the lower unit; wherein said ankle unit includes a U-shaped member for fitting outside the user's footwear or boot, said U-shaped member having side portions provided with outwardly extending pivots, and wherein said lower unit includes inner and outer struts each having a lower end terminating in a slot which fits over one of said pivots to transmit forces from the lower unit to the ankle unit while allowing pivotal movement therebetween, said slots also allowing easy removal of the U-shaped member with the footwear or boot when the user is resting.

2. A knee support according to claim 1, wherein said upper and lower units each have rigid inner and outer side portions, and wherein each said upper unit side portion is connected to a lower unit side portion by an elastic cord which passes in front of a guide held by the cartilage unit;
and wherein said upper unit comprises a flexible, non-stretchable strap incorporating cotton absorbent material and shaped and dimensioned to fit closely around the user's thigh, said strap having its opposite edges provided with mating portions of a zipper-type fastener for holding together said edges when the strap is fitted around a thigh, said zipper-type fastener allowing said upper unit to be accurately and reproducibly located on the user's thigh, with uniform distribution of pressure, in a predetermined position which, relative to the ankle unit, ensures that when the upper unit is securely positioned, a substantial portion of a person's weight is transmitted from the floor or like surface to the upper unit via the lower and intermediate units, so relieving pressure on the user's knee.

3. A knee support according to claim 1, wherein said intermediate, cartilage-supporting unit is pivotally connected to each said upper and lower units by a pivot and by movement limiting means, said latter means, for each connection, including a part-circular slot on one of the units centered on the pivot of that unit and a pin projecting from the adjacent unit which moves in said slot, whereby said slot limits pivotal movement of the connected units.