Orthopedic walking brace having a curved sole
Described herein are systems and devices for providing an orthopedic walking brace having a housing and a sole with a curved distal surface. The housing is configured to encompass and immobilize a patient's ankle against flexion. The distal surface of the sole has a posterior region, a mid region, and an anterior region. The posterior region is configured to lie under a heel portion of the patient's foot, and the mid region is configured to lie under a center portion of the patient's foot. The anterior region is configured to lie under an anterior metatarsal and toe portion of the patient's foot, and has an Anterior-Posterior curvature that increases from a posterior side of the anterior region toward a middle portion of the anterior region and decreases from the middle portion toward an anterior side of the anterior region.
1. A sole configured for use with an orthopedic walking brace, comprising:
a proximal surface and a distal surface, the proximal surface configured to receive a patient's foot, and the distal surface having a posterior region, a mid region, and an anterior region, wherein:
the posterior region is configured to lie under a heel portion of the patient's foot and has a first anterior-posterior (AP) curvature,
the mid region is configured to lie under a center portion of the patient's foot and has a second AP curvature, and
the anterior region is configured to lie under an anterior metatarsal and toe portion of the patient's foot, and has a third AP curvature that increases from a posterior side of the anterior region toward a middle portion of the anterior region and decreases from the middle portion toward an anterior side of the anterior region.
2. The sole of claim 1 , wherein the first AP curvature increases from a posterior side of the posterior region toward a middle portion of the posterior region and decreases from the middle portion toward an anterior side of the posterior region.
3. The sole of claim 2 , wherein the first AP curvature has a maximum value less than about 0.25 inch −1 .
4. The sole of claim 2 , wherein a product of an AP length of the posterior region and a maximum value of the first AP curvature has a maximum value less than about 0.7.
5. The sole of claim 1 , wherein the proximal surface is rigid, and the distal surface is flexible, and wherein the distal surface comprises a first material having a first density, and a second material having a second density, wherein the second density is smaller than the first density.
6. The sole of claim 5 , wherein the first material is rubber.
7. The sole of claim 5 , wherein the second material is ethyl vinyl acetate.
8. The sole of claim 1 , wherein the anterior region comprises about 35% of an AP length of the distal surface.
9. The sole of claim 1 , wherein the mid region comprises about 40% of an AP length of the distal surface.
10. The sole of claim 1 , wherein the mid region is configured to lie directly beneath the midfoot.
11. The sole of claim 1 , wherein the third AP curvature has a maximum value greater than about 0.100 inch −1 .
12. The sole of claim 1 , wherein a product of an AP length of the anterior region and a maximum value of the third AP curvature is greater than about 0.35.
13. The sole of claim 1 , wherein the second AP curvature has a maximum value less than about 0.030 inch −1 .
14. The sole of claim 1 , wherein a product of an AP length of the mid region and a maximum value of the second AP curvature has a maximum value less than about 0.15.
15. The sole of claim 1 , wherein the distal surface has a first medial-lateral (ML) curvature that has a first peak adjacent to a medial edge and a second peak adjacent to a lateral edge of the distal surface, and is substantially flat in between the first and the second peaks.
16. The sole of claim 1 , wherein the distal surface is symmetric.
17. The sole of claim 1 , wherein the proximal surface is formed of a plastic material.
18. The sole of claim 1 , wherein a distance between a highest point on the distal surface and a ground surface defines a thickness and a maximum value of the thickness is about 0.75 inches.
19. A method of immobilizing an ankle against flexion while approximating a natural gait, comprising:
providing an orthopedic walking brace, comprising:
a housing configured to encompass a patient's ankle; and
a curved sole having a proximal surface and a distal surface, the proximal surface configured to receive the patient's foot, and the distal surface having a posterior region, a mid region, and an anterior region, wherein:
the posterior region is configured to lie under a heel portion of the patient's foot, and has a first anterior-posterior (AP) curvature,
the mid region is configured to lie under a center portion of the patient's foot, and has a second AP curvature, and
the anterior region is configured to lie under an anterior metatarsal and toe portion of the patient's foot, and has a third AP curvature that increases from a posterior side of the anterior region toward a middle portion of the anterior region and decreases from the middle portion toward an anterior side of the anterior region; and
encompassing the ankle of the patient in said housing,
wherein said curved sole is configured to provide a substantially smooth transition from heel-strike to mid-stance and from mid-stance to toe-off.
20. The method of claim 19 , wherein the curved sole provides a rolling motion at an angular velocity that mimics a natural walking gait cycle.