Bone plate for elastic osteosynthesis

• US 9,700,361 B2
• Filed: 02/19/2016
• Issued: 07/11/2017
• Est. Priority Date: 02/03/2012
• Status: Active Grant

• Current Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Inventors: Madey, Steven M., Bottlang, Michael, Wirtz, Kyle, Tsai, Stanley
• Primary Examiner(s): Yang, Andrew
• Application Number:
  US15/047,702
• Publication Number:
  US 20160166293A1
• Time in Patent Office: 508 Days
• CPC Class Codes: A61B 17/8028 Cushions, i.e. elements forming interface between bone plate and bone
• CPC Class Codes: A61B 17/8047 wherein the additional element surrounds the screw head in the plate hole A61B17/8052 takes precedence
• CPC Class Codes: A61B 17/8052 immobilised relative to screws by interlocking form of the heads and plate holes, e.g. conical or threaded
• CPC Class Codes: A61B 17/8057 the interlocking form comprising a thread
• CPC Class Codes: A61B 17/808 Instruments for holding or positioning bone plates, or for adjusting screw-to-plate locking mechanisms
• CPC Class Codes: A61B 17/86 Pins or screws or threaded wires; nuts therefor A61B17/72 take precedence
• CPC Class Codes: A61B 2017/00221 with wireless transmission of data, e.g. by infrared radiation or radiowaves
• CPC Class Codes: A61B 2017/00862 elastic or resilient
• CPC Class Codes: A61B 2090/064 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61B 2090/065 for measuring contact or contact pressure
• CPC Class Codes: A61B 2090/066 for measuring torque
• CPC Class Codes: A61B 2560/0219 of externally powered implanted units
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 90/06 Measuring instruments not otherwise provided for

Abstract

Embodiments provide a method and device for plate osteosynthesis of a bone fracture that allows angle-stable fixation of the bone fracture, while permitting elastic axial motion at the fracture site in a controlled, symmetric manner to stimulate fracture healing. Embodiments pertain to a bone plate having an outer surface and a bone-facing surface. The bone plate incorporating internal sliding elements containing a threaded receiving hole for bone screws that have a correspondingly threaded screw head. The sliding elements undergo controlled displacement parallel to the longitudinal axis of the plate but are substantially constrained against displacement perpendicular to the longitudinal axis of the plate. The bone screws with threaded heads may be rigidly fixed to the threaded receiving holes in the sliding elements without compressing the bone plate onto the bone surface. Sliding elements are elastically suspended inside the bone plate and undergo dynamic motion.

Claims

1. A method for flexible plate fixation of a bone fracture, the method comprising

approximately aligning the fractured bone members;

and

applying a fixation construct across a fracture wherein the fixation construct comprises a bone plate having an upper surface and a bone-facing surface, the bone plate having one or more receiving holes and a plurality of elastically suspended sliding elements, the fixation comprising using a plurality of bone fasteners that connect the bone fasteners to the bone plate and wherein the bone fasteners are placed into the receiving holes into the sliding elements that are elastically suspended in the bone plate;

wherein the sliding elements are configured to permit controlled translation parallel to the longitudinal axis of the bone plate, while substantially preventing displacement perpendicular to the longitudinal axis of the bon plate, and wherein the bone fastener is rigidly fixed to the sliding elements without compressing the bone plate or sliding element onto a bone surface; and

wherein

wherein the elastic suspension is provided by two or more spring elements.

2. The method of claim 1 wherein the elastic suspension of the two or more spring elements comprises an elastic material.

3. A method of claim 1, where said receiving holes are suspended to preferentially permit translation relative to the bone plate along the longitudinal axis of the plate while substantially constraining motion of the one or more receiving holes in a direction that is perpendicular to the upper or bone-facing surface of the bone plate.

4. A method of claim 1, whereby the spring elements act as elastic springs that suspend the receiving holes in a neutral position relative to the plate in absence of a load application and wherein the elastic swings enable controlled elastic translation of the receiving holes relative to the plate in response to the load application.

5. A method of claim 1, whereby the spring elements dampen transmission of an impact load between the bone plate and the bone member to enhance stability of the fixation construct.

6. A method of claim 1, whereby the spring elements enhance distribution of load transfer between multiple bone fasteners associated with a single bone segment.

7. A method of claim 1, whereby the spring elements prevent at least in part direct contact between the receiving hole and the bone plate to reduce surface wear and material fatigue.

8. A method of claim 1, wherein the elastic suspension of two or more receiving holes and the plate is practiced on one side of a fracture, while the corresponding bone segment is attached to static receiving holes.

9. A method of claim 1, wherein the elastic suspension of two or more receiving holes and the bone plate is practiced on both sides of a fracture.

10. A method of claim 1, wherein the elastic suspension of two or more receiving holes and the bone plate reduces axial stiffness of the fixation constructs by about 40-90% compared to a bone plate construct having static receiving holes.

11. A method of claim 1, wherein one or more spring elements contain a sensor to measure displacement, pressure, or load to capture a presence or magnitude of load transfer between the sensor and the bone plate as a means for estimating the progression of fracture healing.

12. A method of claim 2, wherein the elastic material comprises an elastomer lumen, and wherein the elastomer lumen of one or more of the spring elements contains a means for energy generation to supply transient power to said sensor.

13. A method of claim 2, wherein the elastic material comprises an elastomer lumen, and wherein the elastomer lumen is configured to permit a timed release of pharmacological substances.

14. A method of claim 2, wherein the elastic material comprises silicone.

15. A method of claim 2, wherein the elastic material is bonded to the surface of the bone plate and/or sliding element.