Dynamic response ankle-foot orthosis

• US 6,334,854 B1
• Filed: 09/27/1999
• Issued: 01/01/2002
• Est. Priority Date: 09/27/1999
• Status: Expired due to Term

• Current Assignee: Locke Henderson Davis
• Original Assignee: Locke Henderson Davis
• Inventors: Davis, Locke Henderson
• Primary Examiner(s): POTHIER, DENISE M
• Application Number:
  US09/405,074
• Time in Patent Office: 827 Days
• Field of Search: 602/5-8, 602/23, 602/27-29, 602/65, 128/882, 128/846, 264/222, 264/223, 264/DIG.30, 361/40, 121/42.N, 121/46.M, 156/245, 156/307.3, 428/36.1, 428/36.2, 442/260, 442/261, 442/263, 442/305, 442/318
• US Class Current: 602/6
• CPC Class Codes: A61F 13/04 Plaster of Paris bandages; Other stiffening bandages A61F13/06 - A61F13/15 take precedence
• CPC Class Codes: A61F 5/0111 for the feet or ankles

Abstract

An orthotic device developed and customized to control the desired movement of the patient'"'"'s defective lower limb. The device incorporates a footplate made of a rubber-like elastomeric material and a proximal segment that encompasses the foot at the metatarsophalangeal joints and the shin portion of the leg. This proximal segment is made of a rubber-like elastomeric material laminated into multiple layers of fabric throughout the proximal segment. Additional strips of fabric are positioned within the proximal segment of the device to limit or promote certain motions within the foot and ankle. This device incorporates a continuous closure from the foot to the proximal segment, creating total contact and hydrostatic containment of the foot and lower leg. The combination of total contact, hydrostatic compression, the multiple layers of fabric with strategically placed strips of fabric laminated with the elastomeric material and the molded footplate combine to provide limited and graded motion of the foot and ankle complex during the gait cycle of ambulation. Much like taping the foot and ankle, this device applies tensile forces to the foot and ankle to control motion. This system applies dynamic corrective forces to the foot and ankle complex during different events of the gait cycle to promote a more normal gait pattern.

Claims

1. A method of controlling the movement of a defective lower limb of a patient, comprising the steps of:

a) having a person with specific corrective needs in the movement of a lower limb;

b) evaluating and determining by an orthotic examination design characteristics needed to improve movement of the defective lower limb;

c) constructing a specifically designed plaster mold that is a duplicate of the defective lower limb;

d) coating the mold with an elastomeric resin for constructing over the mold a laminated set-up for lower limb motion control;

e) applying at least two layers of nylon stockinette over the mold;

f) attaching aramid fiber strips, being of selected width, in specific patterns onto the layers of nylon stockinette, and strategically placed on the layers of nylon stockinette to coincide with the lower limb movement needs previously determined by the orthotic evaluation;

g) applying at least two additional layers of nylon stockinette over the aramid fiber strips forming the laminated set-up;

h) inverting the laminated set-up onto a vacuum stand;

i) covering the laminated set-up with a dampened poly vinyl alcohol sleeve, having an upper end closed and sealing a lower end to the vacuum stand, thus allowing a sufficient vacuum to occur between the surface of the mold and the poly vinyl alcohol sleeve, for drying purposes;

j) opening the upper end of the poly vinyl alcohol sleeve and applying uniformly to the laminated set-up, an elastomeric resin that produces a coating;

k) re-closing the upper end of the poly vinyl alcohol sleeve and allowing the laminated set-up time for drying under vacuum,

l) heat-curing the laminated set-up for a sufficient time under sufficient heat;

m) cooling the laminated set-up to room temperature and removing any excess elastomeric resin from a toe section of the laminated set-up;

n) soaking the laminated set-up in hot water and washing the poly vinyl alcohol from the laminated set-up;

o) drying the laminated set-up and sanding a plantar surface of a foot section of the laminated set-up until fibers of the nylon stockinette layers are exposed;

p) positioning the laminated set-up in an inverted position with the foot section horizontal in the sagittal and frontal plane;

q) building a dam of selected height around a border of the foot section with masking tape;

r) filling the plantar surface with elastomeric resin and allowing it sufficient time to cure;

s) heating the laminated set-up for a sufficient time, for curing purposes;

t) removing the masking tape and, sanding away excess material,

u) cutting a center dividing line down the front of the laminated set-up and trimming away the lamination exposing a toe area section;

v) constructing closing means;

w) removing the laminated set-up from the mold to provide a pliable orthosis for controlling the motion of the defective lower limb; and

x) placing the defective lower limb of the patient inside the orthosis with the closing means whereby the specifically placed strips of the orthosis control the defective lower limb movement in accordance with the previously determined orthotic design characteristics.

2. A method of controlling the movement of a defective lower limb of a patient, comprising the steps of

a) orthotically evaluating a person with specific corrective needs in the movement of a defective lower limb;

b) determining design characteristics needed to improve the defective lower limb movement;

c) designing and fabricating a contoured footplate, for supporting a desired lower limb position;

d) positioning the footplate beneath a foot of the lower limb in contact with the plantar surface of the foot;

e) incorporating the footplate, foot and lower leg into a plaster cast, encompassing the entire foot and leg up to the fibula head and holding in a fixed orthotically desired position;

f) after sufficient hardening, making a cut line and removing the cast and the footplate from the foot and leg;

g) sealing the cast along the cut line;

h) filling the cast with molding plaster creating a mold of the defective lower limb;

i) removing the cast with the footplate from the hardened plaster mold and correcting any needed adjustment to the mold with regards to the foot and ankle;

j) adjusting a surface of the plaster mold as needed to desired contours by applying and removing plaster and by smoothing the surface of the molds, thus creating the mold of the patient'"'"'s lower limb;

k) drying the mold in a low temperature oven;

l) coating the entire mold with an elastomeric resin for constructing over the mold a laminated set-up for lower limb motion control;

m) applying at least two layers of nylon stockinette over the mold;

n) attaching aramid fiber strips of selected width and having light adhesive in specific patterns onto the nylon stockinette layers, and strategically placed on the nylon stockinette layers to improve the defective lower limb movement as previously established by the orthotic evaluation;

o) applying at least two additional layers of nylon stockinette over the aramid fiber strips forming the laminated set-up;

p) inverting the laminated set-up onto a vacuum stand;

q) covering the laminated set-up with a dampened poly vinyl alcohol sleeve having an upper end closed and sealing a lower end to the vacuum stand thus achieving a sufficient vacuum between the surface of the laminated set-up and the poly vinyl alcohol sleeve for drying purposes;

r) opening the upper end of the poly vinyl alcohol sleeve and applying uniformly to the laminated set-up, an elastomeric resin that produces a coating;

s) re-closing the upper end of the poly vinyl alcohol sleeve and allowing the laminated set-up drying time under vacuum;

t) heat-curing the laminated set-up for a sufficient time and under sufficient heat;

u) cooling the laminated device to room temperature and removing any excess elastomeric resin from a toe section of the laminated set-up;

v) soaking the set-up device in hot water and washing the poly vinyl alcohol from the laminated set up;

w) drying the laminated set-up device and sanding a plantar surface of a foot section of the laminated set-up until fibers of the nylon stockinette are exposed;

x) positioning the laminated set-up in an inverted position with the foot section horizontal in the sagittal and frontal plane;

y) building a dam, of selected height, around a border of the foot section, with masking tape;

z) filling the plantar surface with elastomeric resin and allowing it sufficient time to cure;

aa) heating the laminated set-up for a sufficient time, for curing purposes;

bb) removing the masking tape and sanding away excess material,

cc) cutting a center dividing line down the front of the laminated set-up and trimming away lamination to expose a toe area section;

dd) constructing closing means;

ee) removing the laminated set-up from the mold to provide an orthosis for controlling the motion of the lower limb; and

p1 ff) placing the defective lower limb inside the orthosis, and with the closing means controlling the lower limb movement of the patient to coincide with predetermined orthotic requirements for triplane movement.

3. A method of controlling the movement of a defective lower limb of a patient with an orthosis comprising the steps of:

(a) evaluating specific corrective needs in the movement of a lower limb;

(b) constructing a mold of the defective lower limb;

(c) applying at least one fabric layer over the mold;

(d) attaching at least one aramid strip to control movement of the orthosis to coincide with desired lower limb movement established by the orthotic evaluation;

(e) applying at least two additional layers of fabric over the at least one aramid strip;

(f) applying a dampened poly vinyl alcohol sleeve over the fabric covered mold;

(g) applying elastomeric resin to produce a laminate into the fabric layers;

(h) curing the resin;

(i) sanding a plantar surface of the laminate until one of the fabric layers is exposed;

(j) building a dam around the border of a foot section of the laminate;

(k) filling the plantar surface of the foot section within the dam with a thickness of elastomeric resin;

(l) curing the resin;

(m) removing the orthosis from the mold; and

(n) placing the orthosis over the defective lower limb of the patient to control limb movement.