CA1174926A - Modified orthotic device - Google Patents

Abstract

IMPROVED MODIFIED ORTHOTIC DEVICE

ABSTRACT OF THE INVENTION

An improved orthotic device for use in knee stabilizers and modified cast and fracture braces that allows movement of the leg and knee for lateral support, protection and rotational stability of a knee-joint and ligaments consisting essentially of a three-segment double hinged single side brace employed in a paired configuration; said brace having a rigid support bar or rod positioned opposite the knee-joint;
said support pivotally hinged at one end to an upper flange and at the other end pivotally hinged to a lower flange; the upper flange secured to an attachment wing and the lower flange secured to an attachment wing; each attachment wing for securely embedding in casting material one end over the thigh and one end over the lower leg or calf; said double hinged brace modified with stop means for limiting flexion and extension of the knee-joint and leg.

Description

1~7~9;Z6 IMPROVED MODIFIED ORTHOTIC DEVICE

BaCRGRO~D OF TÆ I~VENTION
_ - This invention relates to an improved orthotic de~ice for use in a new assembly of knee stabilizer and modified cast brace. More particularly, this invention relates to a new and improved double hinged single side brace for use in support and alignment of the joints, security of limb position, prevention of change in position attributed to rotatory forces on the fxacture ~ite, prevention of swelling complications, and economy o~ physician's time. Support and protection is to the medial collateral ligament of lateral collatera~
ligament of the knee.

The knee-joint is made up of two condyloid ~oints and a third joint, partly arthrodial, but not completely so, since the articular surfaces are not mutually adapted to each other, so that the mo~ement is not a simple gliding one. The principal moYemen~s that take place at the knee-joint are flexion and extension. The movements of flexion and extension at this joint aiffer from those in a typical hinge joint, such as the elbow, in that the axis around which motion takes place is not a fixed one but shifts forward during extension, as a gliding movement is superposed on the rolling, and shifts backward during flexion. ~$~
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llt~49~6 Although the knee-joint has been described as a hinge joint, it is reall~ of a much more complicated character. It must be regarded as consisting of three articulations, of two different kinds. The first kind is a condyloid articulation; in this form of joint, an o~oid articular surface, or condyle, is received into an elliptical cavity in such a manner as to permit flexion, extension, abduction, adduction, and circumduction, but no axial rotation. The second kind of articulation involved is arthrodial; this is a joint which permits only gliding movement. It is formed by the apposition of plane surfaces, or one slightly concavei-~he-ether-slightly convex, the amount of motion between hem being limited by the ligaments or osseous processes surrounding the articulation.

Persons who have sustained knee injuries, who have had operations to remove cartilage, or who have weak knee-joints from causes, such as arthritis or ~theletes who have sustained an injury to the medial collateral ligament or lateral collateral ligament of the knee, need protection principally against lateral motion of the knee, that is, motion may be the result, for example, of a blow to the side of the knee. At the same time, a suitable knee brace should not interfere with the normal flexion and extension of the leg. The brace should protect the knee against sidewise motions during both flexion and extension, this means that the bracing structure should continue to lie parallel to-the parts--of the=le~ above and below the kne~-joint in all-position~ of the brace structure and should remain substantially at the knee and provide protection to the ksee, - -.; - , , , -., .

11~7~

The knee-joint has four principal ligaments r one on either side and two on the inside. There ligaments may be strained or torn in sports and accidents.
Injuries to these ligaments can be serious and must be properly treated if disability is to be avoided~ Above all, repeated injury or strains before healing must be avoided. All degrees of ligament injuries will lead to some atrophy of the quadriceps and hamstring muscle groups.

Many previous orthotic devices for use as knee braces and protection devices have been simple hinged structures pivotable about a fixed point, which cannot move parallel to the complex motion of the knee joint. Some knee braces for support and protection of the knee-joint comprises both an inner and outer bracing structure each a rigid planar and elongated arm and pivoted about a fixed point. The fixed point lies on and parallel to the knee and leg. During motion and a sideways blow, the rigid planar arms may cause further injury or discomfort to the already injured ligaments of the knee-;oint.

Some of the previous knee braces fail to provide ~rotection to the injured knee ligaments. ~hile other braces may lie parallel to the leg and knee-joint while it i5 extended when the leg is flexed, the bracing structure fails to follow the motion accurately.

The instant improved orthotic device may be used in cast bracing for derotational or knee bracing; also used to distribute the load of functional below-the-knee fracture bracing. Cast bracing stresses proper alignment of the joints, security of limb position, prevention of li749~6 .

swelling complications and economy of physician's time.
A special feature is a double hinged single side brace utilized in paired configuration on each side of the knee-joint. Within the features of the improved modified cast brace of this invention is a modified double hinged double axis joint that restricts the arc of the leg motion to safe limits, generally 20 to 90 degrees. Functionally, the use of the modified cast brace joint compares favorably with previous treatments.
Early motion was extremely well tolerated, the stability of operated knees was well supported and aided in management of serious knee ligament injuries.

Clinical and laboratory evidence has proven that prolonged immobilization is detrimental to synovial joints. Traditional treatment of knee-joint and leg in~uries commonly involves immobilization for six to eight weeks. Periods of immobilization of this length produce alterations in the biochemistry of connective tis8ue, the micro- and ultra-structure of synovial membrane, cartilage, tendon, and in the biomechanical properties of the ligament-bone unit. Muscle atrophy and vascular thrombi are common extra-articular complications of prolonged immobilization.

Means for minimizing these undesirable effects are desirable. Therefore, early protected motion will re8ult in minimizing the undesirable effects. The instant invention is a specific modified cast brace which allows limited knee motion yet protects healing structures from disruptive stresses.

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- 1~74926 SUMMARY OF THE INVENTION

Objects of the present invention are to provide for an improved modified orthotic-cast brace assembly w~ich permits and provides freedom of movement of the knee during flexion and extension of the leg in a cast S without restriction or physical discomfort during movement.

Another object of the present invention is to provide an improved modified orthotic-cast brace assembly which permits and provides freedom of movement of the knee during flexion and extension of the leg in a cast without restriction or physical discomfort during movement.

Another object of the present invention is to provlde an improved modified orthotic-cast brace a~embly which permits and provides for use on an already injured knee and provides prevention of further ln~ury or strain.

Another object o$ the present invention is to provide a paired configuration of rigid double hinged single side orthotic-knee brace pivotally hinged to upper and lower flanges and attachment wings for easy ~ecuring and removal to the cast material on the wearer's leg.

It i~ another object to provide such a modified orthotic-cast brace and stabilizer that does not interfere with normal extension and flexion of the wearer's leg while in the cast, while preventing sidewise motion of the knee-joint whether the leg is ,, .

~:1749Z6 flexed or extended giving added ~upport and comfort thereto and providing rotational stability.

The cast brace assembly of the present invention includes a bracing structure comprising a rigid support bar substantially having an optional concave off-set through its center portion, and at one end pivotally hinged to an upper flange and at the other end pivotally hinged to a lower flange. The center portion having the optional concave off-set of the rigid support is placed along side the knee-joint.

In preferred embodiments, the present invention encompasses at least one improved orthotic device as a knee stabilizer and derotational for support and protection of a knee joint and leg said device described as a double hinged ~ingle side brace comprising a rigid support structure having an optional off-set or involuted design through its center portion. Butt-joint hlnge~ provide a less cumbersome hinge arrangement. Said off-Qet is optionally formed by raising the center bar or rod by bushings or spacers, or by bending of the center rod or bar, or by bending the upper and lower flanges and connecting there between on the raised portion of the flange a flat straight support bar or rod. The upper flange to which the upper end of the rigid support structure is pivotally hinged to the wearer's upper leg embedded in the cast material above the knee-joint for movement with the upper leg,and limited motion paraliel to the upper leg, and lower flange to which the lower end of the rigid support structure is pivotally hinged to the wearer's lower leg embedded in the cast material below the~nee-joint for movement with the lower leg and limited motion parallel to the lower leg. The support and stabilizing structure has a single rigid Qupport bar or rod optionally having an off-set through its center portion and doubly hinged each at the upper and lower end of the rigid support bar. If the off-set is accomplished by bending the upper and lower flanges, or if the bushings are used to achieve the of~-set configuration, then the rigid support bar or rod is flat and straight between the flanges. The movement of the leg by normal flexion and extension of the wearer's knee is freely permitted by the double hinged arrangement.
The movement comprises any manner consistent with the double hinged action permitted by the rigid support bar and normal to the plane of the rigid support bar, thereby preventing sidewise motion of the knee-joint.

Other o~jects, features and advantages will appear from the following description of a preferred embodiment of the invention, taken together with the attached drawings, in which:

The improved orthotic device assembly consists é~entially of a bracing structure consisting essentially of a rigid support bar or rod substantially having a center portion; at each end of said center portion, there is pivotally hinged thereto extension flanges.
Securely attached to each extension flange there are optionally attachment wings. The attachment wingæ are u~ed to assist in positioning and embedding the exten-~ion flanges into the casting material to secure the ca~t brace to the casting material. Alternative to the optional attachment wings, the extension flange itself may be flared to simulate the attachment wings. The flanges can be contoured with bending irons to allow fluQh apposition to the cast.

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. j~, . , 117~9;26 FIG. 1 shows the improved orthotic device adapted in a modified cast brace according to the present invention in paired configuration in place with respect to the extended leg of the wearer;

FIG. 2 shows the orthotic device in a modified cast brace according to the present invention in relation to the flexed leg of the wearer;

FIG. 3 is a perspective view of the improved orthotic device according to the present invention;

FIG. 4 is a detailed.view of a stop means for regulating or restricting movement in the orthotic device;

FIG. 5 is a perspective view of alternative arrangements for positioning the center support bar or rod~ and FIG. 6 is a perspective view of alternative flared flanges for attachment.

Referring to the drawings, FIGS. 1-6, the orthotic device of the present invention includes a 2Q 61ngle rigid support bar or rod 1 having through the center portion a support bar or rod 5. The support bar or rod 5 has two end portions which are continuations of the center support bar or rod. Each end portion i~ provided with an opening which accommodates a means.
for pivotally fastening 4 and 6 to each end portion of the ~upport bar or rod to extension flanges 3 and 7.
The flanges 3 and 7 are pivotally fastened at 4.and 6 to each end portion of the rigid support bar or rod 5.

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~174926 Such pivotal connection is essential to the function of the cast brace, as discussed in the following.

Each of the flanges 3 and 7 are terminated integrally with optional attachment wings 2 and 9.
Each attachment wing is provided perpendicular to the connecting flange. Alternatively, the flanges may be flared to simulate the attachment wings as in FIG. 6.
Referring to FIG. 1 and FIG. 2, the orthotic device is in place on the wearer's leg. The flanges 3 and 7 terminated by attachment wings 2 and 9 or flaring of the flanges are generally parallel to the upper and lower parts of the wearer's leg even at flexion or extension. The flanges and optional attachment wings which are securely fastened to each other or using flared flanges, are embedded into the casting material.
Thereby, the orthotic device is used in a modified cast or fracture brace and becomes an integral part of the Cast.

The center portion 5 of the orthotic device can be optionally designed off-set or involuted design to avoid pressure against the knee-joint of the wearer.
As ~hown in FIG. 5, various alternative configurations are possible for attachment and positioning of the center portion 5. The pivotally mounted flanges 3 and 7, wings 2 and 9 or flared flanges are securely embedded in the cast material on the wearer's leg, flange and attachment wing,or flared flanges,in the upper part of the cast above the knee-joint and flange and attachment wing, or flared flanges, in the lower part of the cast below the knee-joint. The three part construction with the double hinged action allows the stabilizer to translate the normal leg action of extension and flexion ,, ., ~174~6 --lV--into the confoxmed and supported orthotic bracing structure integral with the cast. The combination of motions permitted by the three part construction results in the motion of the attachment wings and flanges with respect to the rigid support bar or rod that closely parallels that natural action of the knee-joint. The rigid support bar or rod l closely and accurately follows the action of the wearer's knee and at all times continuing to provide support and stability to the knee ~oint while the leg is in a cast. Especially protection against sidewise forces and rotational stability is provided.

The improved orthotic device used in a modified ca~t brace is attachable to the inner or outer leg.
Preferably the orthotic device in a modified cast brace is positioned and secured in paired configuration on both sides of the knee opposite the orthotic center of the knee to provide rotational stability. The center portion of the rigid support bar or rod is placed directly over the medial or lateral ligament.

~, By the double hinge arrangement, the motions of flexion or extension are easily followed by the modified cast brace employing the orthotic device with the accompanying cast support. The principle upon which the invention is based, as well as the operation of the three-segment double hinged arrangement, i~ be~t understood by referring to FIG. l and FIG. 2.
The bracing structure remains generally parallel to the knee-~oint, but the action of the joint formed by the stabilizer accurately parallels the action of the ndividual wearer' 8 knee. At all times, the orthotic device and knee stabilizer of the modified cast br~ce ; of this invention remains substantially displaced, . . .

.;
., .,.
. ~
. .
., -`` 117~9;~6 but parallel and adjacent to the knee-joint, continuing to provide protection and support. Translational motion of the stabilizer of the modified cast brace is limited by being secured into the casting material.

By using the present invention, it is thus possible to have a convenient, effective and comfort~ble means for stabilizing and supporting the leg and knee-joint and thereby eliminate discomfort or possible injury or reinjury to the leg. More importantly, the improved modified cast brace prevents change in position which otherwise is attributed to rotating forces on the fracture site. The double hinge arrangement is a novel feature among orthotic devices as modified cast braces and fracture braces. Also, the center portion of the rigid support bar or rod of the knee stabilizer of the ¢ast brace i8 novel in that it does not place pressure on the knee-joint. Acting together, the improved bar or rod and double hinge arrangement with means or re~tricting movement of the leg form the basis for an original and useful improvement in the design, function and operation of the present orthotic device.

Although a direct comp æ ison between the present construction and other presently known conventional cast brace structures is difficult, it is the opinion of person3 who have used the orthotic device in a modifled cast brace that more than satisfactory results were obtained. For example, football players, who had each experienced leg injuries1 wore the described orthotic device stabilizer and cast brace. By being able to have some motion to the injured leg, rehabilitation and full use of the leg was enhanced. ~ach player was then able to perform his prescri~ed duties witho~ 0x~ended -1 1 7'~26 recuperation. Joint motion and muscle function are maintained so that they are at a functional level at the completion of the treatment.

In use, the orthotic device used in an improved modified cast brace is used in a cast brace assembly which protects healing structures from disruptive stresses on the leg or knee especially rotational forces.
In the use, the modified cast brace assembly with the orthotic device is employed in a leg cast on patients with a variety of problems in fractures of the proximal tibia and distal femur. Among the knee and leg problems including acute ligamentous injuries, medial and lateral reconstructions, cruciate ligament prosthesis, total knee arthroplasties, tibial plateau fractures, and patello-femoral arthroplasties.

The impr~ved orthotic device with the stop means for restricting the range of motion of the leg, ~enerally from about 20 to about 90 degrees, the arc and total range of motion may be varied according to the individual pathology. The improved modified cast brace permits isotonic, isometric and progressive resistance exercises while in the cast brace. The cast is worn from six to eight weeks or for a time period as required.

11749Z~;

The hinged long leg cast includ~ng t~e dou~le hinged three-segment-brace support is practical from the standpoint of cost, t~me and ease of application.
Also, the comfort to the patient is notable, both in ease of movement when permitted, in weight and functional stability and support. Another distinct advantage of the modified cast brace is the possible reuse of t~e joint which lessens the cost.

More particularly, a notable advantage to t~e use of the instant orthotic devi¢e in a modified cast brace assembly with the three-segment double hinge brace is the ease of application. Many other cast brace joints and assemblies require the joints need be aligned parallel and over the axis of rotation of the knee. This critical alignment requires an alignment jlg - a special tool is required~ The instant joint is unique since it does not require special alignment.
It is sufficient to place one joint on each side of the knee with the placement reasonably determined over ,the center of rotation for the knee. Orientatio~ of the joints and extensions contoured to the upper and lower leg curvature allows ease of placement in the cast with maximum comfort to the patient.

When applying the orthotic device in a modified cast brace with the joint in place, plaster may be used as a general cast material. Some of the newer synthetic materials may be more durable with active athletic patients. Also, newer synthetic materials are lighter in weight than plaster. In use of any casting material, the joints are then easily applied to the cast by implanting the extended flanges and attachment wings thereto. Means for integral .
attachment of the orthotic device to the casting material is provided.

Within the embodiment of this invention i9 the means for regulating and restricting the movement of the cast brace. Because of the ease of movement of the knee fitted with an improved cast brace, including the orthotic device, there is a need for a means for regulating and restricting the movement of the leg.
Confined movement is often recommended at early stages of healing. Later, freer movement of the knee and leg can be permitted. Therefore, patients with operated cases fail to require longer time for recovery of motion. Repaired knees which n loosen" during immobilization does not apply to cases employing the instant device. Therefore, knees treated with early protected motion show no harm and enhance recovery and early full use of the knee joint.

A1BO~ included within the invention, ~s the means for angular positioning of the leg. Also, cond dered is a stop means for limiting the folding movement of the mechanical double hinged joint. There i~ capability for free movement of the knee, restricted movement and fixed angular positioning of the knee-joint~
Varied capability to control the knee and leg mo~ement give~ early protected motion, with early lim~ted knee motion, followed by free motion. Actually, motion can be initiated at any time, if the patient has a condition which will permit movement.

1.~7~ 6 The feature of the orthotic device in the modified cast brace is the three-segment double hinged joint, uncommon to other fracture braces. In addition, the modified cast brace is provided with stop means for adjusting to limit both flexion and extension of the leg and knee-joint, pre-set and resettable means for added freedom in setting a range of knee motions.
Setting can range from a locked position to a limited motion to a completely adjustable brace to desired limits.

The modified cast brace can be applied with conventional casting materials. For example, if a long leg cast is suitable to the pathology, it can be applied as over a cast sock and elastic knee cage. These items are optional. Additionally, felt pads may be placed over the malleoli, the extensor hallucis longus tendon on the dorsum of the foot, and the peroneal nerve. An additional piece of felt may be placed over the patella to create an identifiable bump for trimming and to turn the edges away from the shin. The modified cast brace with the improved orthotic device in paired configuration is embedded in the casting material on each site of the knee-joint.

The modified cast brace with the improved orthotic device of this invention is useful in many ailments of the leg, knee and knee ligaments. Both pre- and post-operative utility has been realized.
Chronic and acute knee and knee ligament injuries can be treated and rehabilitated. In most cases, rehabilitation time after treatment was shortened.
Quadriceps and hamstring tone rated fair to good on removal of the modified cast brace. L~osening of 1:174~2~ .

repaired knees can be prevented since complete immobilization is not required.

While certain novel features of the invention have been disc~osed herein, and pointed out in the annexed claims, it will be understood that, in accordance with the doctrine of equivalents, various omissions, substitutions and changes may be made by those skilled in the art without departing from the spirit and scope of the invention.

Claims (12)

WHAT IS CLAIMED IS

1. A modified cast brace with an orthotic device consisting of:

a) a rigid center support member having an upper end and a lower end;

b) an upper flange non-slidably pivotally hinged to said upper end of said center support member;

c) a lower flange non-slidably pivotally hinged to said lower end of said center support member; and d) 5 a cast in which said orthotic device is embedded.

2. A modified cast brace with an orthotic device consiting of:

a) a rigid center support member having an upper end and a lower end;

b) an upper flange non-slidably pivotally hinged to said upper end of said center support member;
c) a lower flange non-slidably pivotally hinged to said lower end of said center support member;

d) attachment wings each separately and individually securely attached to said upper and lower flanges; and e) a cast in which said orthotic device is embedded.

3. The modified cast brace of Claims 1 and 2 wherein said brace is embedded in and integral with cast material in position on a leg having the center support member of the orthotic device in close proximity to the knee-joint.

4. The modified cast brace of Claim 2 wherein said attachment wings are perpendicular to said attached upper and lower flanges.

5. The modified cast brace of Claim 2 wherein said upper and lower flanges are flared configurations of the flange.

6. The modified cast brace of Claims 1 and 2 wherein said rigid center support member is an off-set or involuted design.

7. The modified cast brace of Claims 1 and 2 wherein said rigid center support member is a support bar or rod.

8. The modified cast brace of Claims 1 and 2 wherein said pivotally hinged upper and lower flanges having preset and resettable stop means for limiting knee and leg motion.

9. The method for providing protected motion for knee-joints in conjunction with a leg cast on patients consisting of positioning and securely embedding in the cast material on the patient's leg a brace having a double-hinged three-segmented arrangement with a center support member, an upper extension flange and lower extension flange non-slidably pivotally hinged to said center support member, attachment wings attached to each upper flange and lower flange.

10. The method of Claim 9 wherein said brace is used in paired configuration on each side of the knee-joint.

11. The method of Claim 9 wherein said brace contains stop means for restricting the range of motion of the leg from about 20 degrees to about 90 degrees of arc.

12, The method of Claim 9 wherein the upper extension flange is placed over the thigh, and the lower extension flange is placed over the lower leg,