SKELETAL BONE FIXATION MECHANISM

• US 20150039034A1
• Filed: 08/01/2013
• Published: 02/05/2015
• Est. Priority Date: 08/01/2013
• Status: Active Grant

• Current Assignee: Bruce Frankel, Mark Semler
• Original Assignee: MUSC Foundation For Research Development (State of South Carolina)
• Inventors: FRANKEL, Bruce M., SEMLER, Mark Evald
• Granted Patent: US 10,786,283 B2
• Time in Patent Office: Days
• US Class Current: 606/261
• CPC Class Codes: A61B 17/7011 Longitudinal element being non-straight, e.g. curved, angled or branched adjustable length longitudinal elements A61B17/7014; A61B17/7019 takes precedence, e.g. coil springs
• CPC Class Codes: A61B 17/7013 the shape of the element being adjustable before use adjustable length plates A61B17/7014
• CPC Class Codes: A61B 17/7032 Screws or hooks with U-shaped head or back through which longitudinal rods pass
• CPC Class Codes: A61B 17/7085 for insertion of a longitudinal element down one or more hollow screw or hook extensions, i.e. at least a part of the element within an extension has a component of movement parallel to the extension's axis
• CPC Class Codes: A61B 2090/037 with a frangible part, e.g. by reduced diameter
• CPC Class Codes: A61B 2090/066 for measuring torque
• CPC Class Codes: A61B 90/06 Measuring instruments not otherwise provided for

Abstract

A skeletal fixation apparatus may include two or more bodies that are attached to two or more screws that have been inserted into vertebral bodies associated with a patient. The apparatus may also include two or more cylindrical members that are attached to the bodies to control the movement or alignment of the bodies when the skeletal fixation apparatus is being installed in the patient. The apparatus may further include a rod that includes a first curvature and a second curvature. The first curvature may be different than the second curvature and may be based on a medical diagnosis associated with stabilizing the vertebral bodies. The second curvature may enable the bodies to be immovably fastened to the rod in a manner that precludes the cylindrical members from contacting each other or causing a false torque condition to exist when the skeletal fixation apparatus is installed in the patient.

Claims

1. A skeletal fixation apparatus, comprising:

two or more bodies that are attached to two or more screws that have been inserted into vertebral bodies associated with a patient;

two or more cylindrical members that are attached to the two or more bodies to control the movement or alignment of the two or more bodies when the skeletal fixation apparatus is being installed in the patient; and

a rod that includes a first curvature and a second curvature,

the first curvature being different than the second curvature and being based on a medical diagnosis associated with stabilizing the two or more vertebral bodies, and

the second curvature enabling the two or more bodies to be immovably fastened to the rod in a manner that precludes the two or more cylindrical members from contacting each other when the skeletal fixation apparatus is installed in the patient.

2. The skeletal fixation apparatus of claim 1, where a first body, of the two or more bodies, is attached to a first portion of the rod that corresponds to the second curvature.

3. The skeletal fixation apparatus of claim 2, where a second body, of the two or more bodies, is attached to a second portion of the rod that does not correspond to the second curvature.

4. The skeletal fixation apparatus of claim 1, where a first longitudinal axis, associated with a portion of the second curvature, intersects a second longitudinal axis, associated with a first cylindrical member of the two or more cylindrical members, in a manner that precludes the first cylindrical member from making contact with a second cylindrical member, of the two or more cylindrical members, when a first body, of the two or more bodies and to which the first cylindrical member is attached, is immovably fastened to the portion of the second curvature.

5. The skeletal fixation apparatus of claim 4, where the first longitudinal axis is approximately perpendicular to the second longitudinal axis when the when the first body is immovably fastened to the portion of the second curvature.

6. The skeletal fixation apparatus of claim 5, where the first longitudinal axis being approximately perpendicular to the second longitudinal axis when the when the first body is immovably fastened to the portion of the second curvature precludes a false torque condition from being created,

The false torque condition enabling the first body to move relative to at least one of the two or more vertebral bodies when first cylindrical member is detached from the first body.

7. The skeletal fixation apparatus of claim 1, further comprising:

a particular second curvature that is different than the first curvature or the second curvature, the particular second curvature enabling,

a first body, of the two or more bodies, to be immovably attached to the particular second curvature, and

a second body, of the two or more bodies, to be immovably attached to the second curvature, the second body being different than the first body.

8. The skeletal fixation apparatus of claim 7, where the second curvature and the particular second curvature are aligned to enable the first body and the second body to be immovably attached to the rod in a manner that precludes a first cylindrical member, attached to the first body, from making contact with a second cylindrical member attached to the second body.

9. The skeletal fixation apparatus of claim 7, where the second curvature is associated with a first plane within a three-dimensional space and the particular second curvature is associated with a second plane within the three-dimensional space,

the first plane corresponding to one of a coronal plane, a saggital plane, or a transverse plane,

the second plane corresponding to a different one of the coronal plane, the saggital plane, or the transverse plane.

10. The skeletal fixation apparatus of claim 1, where the second curvature corresponds to a complex curvature in three-dimensions, the complex curvature being associated with two or more of a coronal plane, a saggital plane, or a transverse plane.

11. The skeletal fixation apparatus of claim 1, where the second curvature is concave relative to the first curvature.

12. The skeletal fixation apparatus of claim 1, where the second curvature is convex relative to the first curvature.

13. A method comprising:

obtaining parameters associated with a medical diagnosis in connection vertebral bodies of a patient that are to be stabilized by installing a skeletal fixation assembly, the parameters identifying a first curvature of a fixation rod, associated with the skeletal fixation assembly, to be used to stabilize the vertebral bodies,

identifying, based on obtaining the parameters, a second curvature is to be included in a segment of the fixation rod, the second curvature being different than the first curvature and enabling a first body, associated with the skeletal fixation assembly, to be immovably attached to the segment in a manner that precludes a first cylindrical member, removably attached to the first body, from making contact with a second cylindrical member, associated with the fixation assembly;

modifying the segment of the fixation rod in a manner that includes the second curvature, based on the identification of the second curvature; and

installing, in the patient, the skeletal fixation assembly in a manner that includes the modified segment of the fixation rod.

14. The method of claim 13, where the first body is pivotably attached to a screw that is inserted into one of the vertebral bodies.

15. The method of claim 13, where identifying the second curvature further includes:

identifying, based on the parameters, a first location, associated with one of the vertebral bodies, at which a screw is to be inserted into the one of the vertebral bodies;

identifying an axis, associated with the first location, that intersects the fixation rod when the skeletal fixation assembly is installed in the patient;

determining, based on identifying the axis, a second location, associated with the fixation rod, at which the axis intersects the fixation rod; and

identifying the segment based on the determination of the second segment.

16. The method of claim 15, where modifying the segment further includes:

identifying a particular axis that is approximately perpendicular to the axis; and

creating the second curvature, associated with the segment, in a manner that causes a longitudinal axis, associated with the segment to be approximately parallel with the particular axis.

17. The method of claim 15, further comprising:

identifying, based on the parameters, a second location, associated with a different one of the vertebral bodies, at which a particular screw is to be inserted into the different one of the vertebral bodies;

identifying a particular axis, associated with the second location, that intersects the fixation rod when the skeletal fixation assembly is installed in the patient;

determining, based on identifying the particular axis, a third location, associated with the fixation rod, at which the particular axis intersects the fixation rod, when the skeletal fixation assembly is installed in the patient;

identifying a particular segment of the fixation rod to which a second body is to be attached, the second cylindrical body being removably attached to the second body;

identifying a different axis that is approximately perpendicular to the particular axis; and

creating a different second curvature, associated with the particular segment, in a manner that causes a particular longitudinal axis, associated with the particular segment, to approximately align with the different axis,

the second curvature precluding the second cylindrical member from making contact with the first cylindrical member or a third cylindrical member associated with the skeletal fixation assembly when the skeletal fixation assembly is installed in the patient.

18. The method of claim 13, where the second curvature is in the same plane as the first curvature.

19. The method of claim 13, where the second curvature is in a different plane as the first curvature.

20. The method of claim 13, further comprising:

modifying a cross section of the segment in a manner that corresponds to a cross section used by the first body to attach to the segment, the modified cross section precluding the fixation rod from rotating relative to the first body when the first body is immovably attached to the segment.

21. The method of claim 13, where a length, associated with the segment, is greater than a width associated with the first body.

22. An apparatus comprising:

two or more bodies pivotably attached to two or more screws that are installed in two or more bones associated with a patient;

two or more cylindrical members removably attached to the two or more bodies; and

a rod that includes a first curvature and one or more second curvatures,

the first curvature being based on a prior medical diagnosis associated with stabilizing the two or more bones,

the one or more second curvatures being associated with one or more segments of the rod to which the two or more bodies are immovably attached in a manner that precludes the two or more cylindrical members from making contact with each other when the apparatus is installed in the patient.

23. The apparatus of claim 22 where the patient corresponds to a human subject or an animal subject.

24. The apparatus of claim 22, where the two or more bones correspond to at least one of:

vertebral bodies associated with the patient,

bones, associated with the patient, that are different than the vertebral bodies, or

bone fragments associated with the patient.

25. The apparatus of claim 22, where the one or more second curvatures enable the two or more screws to be installed in the two or more bones within a first axial range that is greater than a second axial range in which the screws can be installed if the rod did not include the one or more second curvatures.

26. The apparatus of claim 25, where the first axial range enables the two or more screws to be installed in the two or more bones without causing the two or more cylindrical members to make contact with each other.