SYSTEMS, DEVICES, AND METHODS FOR MONITORING AN UNDER FOOT LOAD PROFILE OF A TIBIAL FRACTURE PATIENT DURING A PERIOD OF PARTIAL WEIGHT BEARING

• US 20120010534A1
• Filed: 07/09/2010
• Published: 01/12/2012
• Est. Priority Date: 07/09/2010
• Status: Active Grant

• Current Assignee: University of Utah Research Foundation (State of Utah)
• Original Assignee: University of Utah (State of Utah)
• Inventors: Kubiak, Erik N., North, Kylee, Hitchcock, Robert W., Chen, Emmon Johnny, Hanson, Jacob Joseph, Collins, Zachary John
• Granted Patent: US 8,758,272 B2
• Time in Patent Office: Days
• US Class Current: 600/592
• CPC Class Codes: A61B 5/1036 Measuring load distribution, e.g. podologic studies
• CPC Class Codes: A61B 5/4842 Monitoring progression or stage of a disease
• CPC Class Codes: A61B 5/6812 Orthopaedic devices
• CPC Class Codes: A61F 5/0585 for the legs toe correcting devices A61F5/019

Abstract

Systems, devices, and methods for measuring an under foot load profile of a tibial fracture patient during a period of partial weight bearing are described. The system may include a walking boot cast. A housing, including an inner surface and an upper surface that cooperate to define an inner cavity, may be oriented with respect to a patient'"'"'s tibia. The upper surface is slidably received within the inner cavity in a piston and cylinder configuration. The system may include a pressure sensor configured to monitor the load profile of a patient during the desired period of partial weight bearing. The pressure sensor may be located below the upper surface. The system may include a noncompressible force transmitter positioned within the inner cavity and at least partially encapsulating an upper portion of the pressure sensor to transmit pressure within the housing to the pressure sensor.

Claims

1. A system for measuring an under foot load profile of a tibial fracture patient during a period of partial weight bearing, the system comprising:

a walking boot cast configured to substantially immobilize the tibia;

a housing oriented with respect to the patient'"'"'s tibia, said housing having an inner surface and an upper surface, said inner surface and said upper surface cooperating to define an inner cavity, said inner surface being substantially rigid, said upper surface being sized to be slidably received within said inner cavity in a piston and cylinder configuration;

a pressure sensor configured to monitor the load profile of a patient during the desired period of partial weight bearing, said pressure sensor located below said upper surface; and

a noncompressible force transmitter positioned within said inner cavity of said housing and at least partially encapsulating an upper portion of said pressure sensor to transmit pressure within said housing to said pressure sensor.

2. The system of claim 1, wherein said pressure sensor is a miniature piezoelectric Wheatstone Bridge pressure sensor.

3. The system of claim 1, wherein said noncompressible force transmitter is a silicone gel.

4. The system of claim 1, wherein said upper surface of said housing is connected to said inner surface of said housing by an elastomer.

5. The system of claim 1, wherein said inner surface is formed from a urethane that is capable of being cast.

6. The system of claim 1, wherein said housing is located in a heel region and/or between a fourth and fifth metatarsal head portion of said walking boot cast.

7. The system of claim 1, wherein said housing includes an aperture to provide a reference pressure for determining the load profile.

8. The system of claim 1, wherein a height of said housing is between approximately half and approximately one sixth of an axial dimension of said housing.

9. The system of claim 1, wherein a major axial inner dimension of said housing is about 26 millimeters, a major axial outer dimension of said housing is about 30 millimeters, a height of said housing is about 7.5 millimeters, and a thickness of said inner surface of said housing is at least about 2 millimeters.

10. The system of claim 1, further comprising a storage device configured to receive the measured load profile from said pressure sensor and wherein the pressure sensor continuously monitors the load profile and transmits the load profile to the storage device.

11. The system of claim 10, wherein the storage device is located remote from the pressure sensor and the pressure sensor being configured for wireless communication with the storage device.

12. The system of claim 1, wherein said pressure sensor is located within a lower portion of said inner cavity of said housing.

13. A method for measuring an under foot load profile of a tibial fracture patient during a period of partial weight bearing, the method comprising:

substantially immobilizing a tibia of a tibial fracture patient;

orienting a housing with respect to the patient'"'"'s tibia, said housing having an inner surface and an upper surface, said inner surface and said upper surface cooperating to define an inner cavity, said inner surface being substantially rigid, said upper surface being sized to be slidably received within said inner cavity in a piston and cylinder configuration;

applying a load to said upper surface of said housing; and

monitoring the load profile generated by applying the load to said upper surface of said housing a pressure sensor located below said upper surface and within a lower portion of said housing.

14. The method of claim 13, further comprising storing the measured load profile from said pressure sensor.

15. The method of claim 13, further comprising transmitting pressure from the load applied to said upper surface of said housing a noncompressible force transmitter.

16. The method of claim 13, wherein monitoring the load profile generated by applying the load to said upper surface of said housing further comprises continuously monitoring the load profile over a two-week period.

17. The method of claim 13, further comprising prior to monitoring the load profile and after applying a load to said upper surface of said housing, detecting the applied load.

18. A method for treating a tibial fracture patient during a period of partial weight bearing, the method comprising:

substantially immobilizing a tibia of a tibial fracture patient;

applying a load to an upper surface of a housing having an inner surface and an upper surface, the inner surface and the upper surface defining an inner cavity, the inner surface and the upper surface being substantially rigid, the upper surface being sized to be slidably received within the inner cavity in a piston and cylinder configuration; and

monitoring the load profile generated by applying the load to the upper surface of the housing a pressure sensor located below the upper surface and within the inner cavity of the housing.

19. The method of claim 18, wherein the housing is located in a heel region and/or between a fourth and fifth metatarsal head portion of the walking boot cast and wherein applying a load to the upper surface of the housing further comprises applying the load in the heel region and/or between the fourth and fifth metatarsal head portion of the walking boot cast.

20. The method of claim 18, wherein the monitoring of the load profile is done without recalibration after first applying the load to the upper surface of the housing.