BONE SCREWS AND METHODS OF USE THEREOF

• US 20110060373A1
• Filed: 09/09/2009
• Published: 03/10/2011
• Est. Priority Date: 09/09/2009
• Status: Active Grant

• Current Assignee: Innovision Inc (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Subchondroplasty Orthopedics, LLC
• Inventors: Glover, Todd A., Pepper, John R., Houston, Samuel A., Russell, Thomas A.
• Granted Patent: US 8,574,273 B2
• Time in Patent Office: Days
• US Class Current: 606/304
• CPC Class Codes: A61B 17/0401 Suture anchors, buttons or pledgets, i.e. means for attaching sutures to bone, cartilage or soft tissue; Instruments for applying or removing suture anchors A61B17/0642 takes precedence; fixation devices for tendons or ligaments A61F2/0811
• CPC Class Codes: A61B 17/7098 wherein the implant is permeable or has openings, e.g. fenestrated screw hollow surgical screws A61B17/864
• CPC Class Codes: A61B 17/80 Cortical plates , i.e. bone plates; Instruments for holding or positioning cortical plates, or for compressing bones attached to cortical plates
• CPC Class Codes: A61B 17/8057 the interlocking form comprising a thread
• CPC Class Codes: A61B 17/8605 Heads, i.e. proximal ends projecting from bone
• CPC Class Codes: A61B 17/861 specially shaped for gripping driver
• CPC Class Codes: A61B 17/864 hollow, e.g. with socket or cannulated
• CPC Class Codes: A61B 17/8811 characterised by the introducer tip, i.e. the part inserted into or onto the bone
• CPC Class Codes: A61B 17/8875 Screwdrivers, spanners or wrenches
• CPC Class Codes: A61B 2017/044 with a threaded shaft, e.g. screws
• CPC Class Codes: A61B 2017/561 Implants with special means for releasing a drug
• CPC Class Codes: A61C 8/0006 Periodontal tissue or bone regeneration support means for endoprosthetic bone substitute or bone graft implants A61F2/2846
• CPC Class Codes: A61C 8/0022 Self-screwing A61C8/0028 takes precedence

Abstract

The invention features bone screws having a threaded screw body and a screw head attached to one end of the screw body, the bone screw further including: a) an interior channel extending longitudinally through the screw head and through at least a portion of the screw body, wherein the interior channel has a width of less than 5.0 millimeters; and b) a plurality of radially-disposed delivery channels connecting the interior channel to the exterior of the screw body, each delivery channel having exterior openings. The invention further features devices that include a bone screw and a delivery manifold detachably attached to the screw head of the bone screw. In addition, the invention features methods of treating a patient having a bone defect by using a bone screw described herein.

Claims

1. A bone screw comprising a threaded screw body and a screw head attached to one end of said screw body, said bone screw further comprising:

a) an interior channel extending longitudinally through said screw head and through at least a portion of said screw body, wherein said interior channel has a width of less than 5.0 millimeters (mm); and

b) a plurality of radially-disposed delivery channels connecting said interior channel to the exterior of said screw body, said delivery channels comprising exterior openings.

2. The bone screw of claim 1, wherein said interior channel has a width of up to 2.0 mm.

3. The bone screw of claim 1, wherein said exterior openings are:

i) of varying cross-sectional areas;

ii) positioned along the length of said screw body;

iii) positioned between one or more threads of said screw body;

iv) arrayed in increasing cross-sectional area along a direction distal to said screw head;

v) substantially circular, substantially cylindrical, substantially slot-shaped, substantially square, or substantially polygonal;

or

vi) comprised of substantially circular exterior openings and substantially slot-shaped exterior openings.

4. The bone screw of claim 1, wherein said delivery channels are sized to generate substantially equal flow rates of a flowable medium extruded through each said delivery channel following introduction of said flowable medium through said screw head into said interior channel.

5. The bone screw of claim 4, wherein said flowable medium comprises bone void filler material, cement, or a pharmaceutical agent.

6. The bone screw of claim 1, wherein each of said delivery channels is tapered along at least a portion of its radial axis or is substantially cylindrical.

7. The bone screw of claim 3, wherein said exterior openings are positioned between alternating threads of said screw body.

8. The bone screw of claim 1, wherein:

i) said interior channel extends through substantially the full length of said screw body;

ii) said interior channel is substantially cylindrical;

iii) said interior channel decreases in width along a direction distal to said screw head;

iv) said interior channel decreases in width substantially linearly as a function of longitudinal distance from said screw head;

or

v) said interior channel decreases in width in a step-wise fashion along a direction distal to said screw head.

9. The bone screw of claim 1, wherein for each of said delivery channel and exterior opening, one or more additional delivery channels and exterior openings are positioned at substantially the same longitudinal distance from said screw head and are positioned substantially 180 degrees, 120 degrees, or 90 degrees apart around said longitudinal axis of said screw body.

10. The bone screw of claim 1, wherein said screw body further comprises one or more exterior grooves extending along at least a portion of the exterior of said screw body and connecting at least a subset of said exterior openings of said delivery channels, wherein the depth of said exterior grooves is less than the depth of said delivery channels.

11. The bone screw of claim 10, wherein each of said grooves is substantially straight, substantially helical, or a combination of both.

12. The bone screw of claim 10, comprising two, three, four, or more exterior grooves that are substantially equidistant relative to each other.

13. The bone screw of claim 1, comprising between 1 and 200 delivery channels.

14. The bone screw of claim 1, wherein said exterior openings range in cross-sectional area from 0.1 mm² to 12 mm², or wherein said exterior openings are substantially circular and range in diameter from 0.1 mm to 4 mm.

15. The bone screw of claim 1, wherein:

i) the length of said screw body is between 10 mm and 200 mm;

ii) the major diameter of said screw body is between 2 mm and 20 mm;

iii) the threads of said bone screw are spaced between 0.5 mm and 500 mm apart;

iv) the radial height of said threads is between 0.1 mm and 20 mm;

v) the diameter of said screw head is between 3 mm and 30 mm;

or

vi) the height of said screw head is between 1 mm and 25 mm.

16. The bone screw of claim 1, wherein said bone screw comprises stainless steel alloy, titanium alloy, commercially pure titanium, cobalt chrome, or polyetheretherketone.

17. The bone screw of claim 3, wherein said screw head:

i) is machined to fit a delivery manifold capable of introducing said flowable medium to the interior channel of said bone screw;

ii) is machined to fit a rotational driver capable of engaging a recess within said screw head;

iii) is hollow;

iv) comprises interior or exterior threads;

v) is substantially circular, substantially hexagonal, substantially square, or substantially hexagonal;

vi) is machined to be driven by a spanner;

vii) has a hexagonal opening, a Robertson opening, a slotted opening, a Phillips opening, a Torx opening, a triple square opening, a polydrive opening, a one-way clutch opening, a spline drive opening, a double hex opening, or a Bristol opening;

viii) further comprises a sealable polymeric barrier that separates an interior region of the screw head from the exterior environment of said bone screw, thereby forming a reservoir within said screw head;

or

ix) is machined for use as a fastener or anchor for an implant.

18. The bone screw of claim 17, wherein said sealable polymeric barrier is a silicone elastomer.

19. The bone screw of claim 1, further comprising an internal plug that fully or partially occludes said interior channel or one or more of said delivery channels, wherein said internal plug is positionable along the length of said interior channel or is a solid state component of said bone screw.

20. The bone screw of claim 19, wherein said internal plug is solid, substantially cylindrical with a hollow core, substantially cylindrical with a hollow core and at least one solid end, or comprises a flowable medium selected from polyethylene, a metal alloy, a bone void filler material, a cement, or a pharmaceutical agent that is capable of releasing from said plug by fluid dissolution.

21. A device comprising:

a) the bone screw of claim 1; and

b) a delivery manifold detachably attached to the outside of said screw head.

22. The device of claim 21, wherein said delivery manifold and said screw head comprise complementary threaded regions.

23. The device of claim 21, further comprising a rotational driver, wherein said rotational driver is positioned within said delivery manifold and is engaged with said screw head, thereby allowing for rotation of said bone screw about its longitudinal axis by rotation of said driver.

24. The device of claim 21, wherein said device is capable of receiving a flowable medium through said delivery manifold, and wherein said bone screw is capable of being tightened, prior to hardening of said flowable medium, by the steps of:

i) inserting said rotational driver through said flowable medium within said delivery manifold;

ii) engaging said screw head with an end of said rotational driver; and

iii) tightening said bone screw into final position by rotating said rotational driver.

25. The device of claim 24, wherein said flowable medium comprises bone void filler material, cement, or a pharmaceutical agent.

26. The device of claim 21, wherein said delivery manifold comprises a Luer lock or other syringe locking mechanism and comprises an injection port diameter greater than or equal to one (1) millimeter (mm).

33. The device of claim 31, wherein said bone screw is the bone screw of claim 1.

34. A method of treating a patient having a bone defect, said method comprising:

a) positioning the bone screw of claim 1 in proximity to said bone defect;

b) introducing a flowable medium into said interior channel of said bone screw;

c) allowing said flowable medium to be extruded through said delivery channels, and

d) allowing said flowable medium to harden, thereby fixing said bone screw in place.

35. The method of claim 34, wherein said flowable medium comprises bone void filler material, cement, or a pharmaceutical agent.

36. The method of claim 35, wherein said flowable medium is extruded through said delivery channels in substantially equal volumes.

37. The method of claim 34, wherein said bone defect comprises a subarticular fracture or a defect of the radius, ulna, fibula, clavicle, humerus, pelvis, femur, patella, tibia, talus, Calcaneus, navicular, cuneiforms, metatarsals, metacarpals, phalanges, scapula, ankle, teeth, mandible, or vertebra.

38. The method of claim 34, wherein said method comprises maxillomandibular or craniofacial fixation, spine fixation, glenoid implant fixation, or temporary fixation for repairing said bone defect in a staged reconstruction.

39. The method of claim 34, wherein said method comprises placing said bone screw within a pedicle, anchoring an interbody device, anchoring a spinal fusion plate and spacer replacement, treating an osteoporotic vertebra, positioning said bone screw in proximity to the spinous processes of adjacent vertebrae, inserting a rod, pin, nail, or bone plate in proximity to said bone defect.

40. The method of claim 34, wherein step a) comprises positioning said bone screw to contact the intraosseous space of a bone.

41. The method of claim 34, wherein, prior to step b), said screw head is fluidically coupled to a delivery manifold capable of introducing said flowable medium to said interior channel.

42. The method of claim 41, wherein step b) comprises introducing said flowable medium to said interior channel through said delivery manifold, and wherein, prior to step d), said method further comprises:

i) inserting a rotational driver through said flowable medium within said delivery manifold;

ii) engaging said screw head with said rotational driver; and

iii) tightening said bone screw into final position by rotating said rotational driver.

43. The method of claim 34, wherein said flowable medium comprises bone void filler material, cement, or a pharmaceutical agent.

27. A device comprising:

a) a bone screw comprising a threaded screw body and a screw head attached to one end of said screw body, said bone screw further comprising;

i) an interior channel extending longitudinally through said screw head and through at least a portion of said screw body; and

ii) a radially-disposed delivery channel connecting said interior channel to the exterior of said screw body; and

b) a delivery manifold attached to said screw head,

wherein said delivery manifold is configured to receive a rotational driver within the interior to said delivery manifold, wherein an end of said rotational driver is configured to engage with said screw head and wherein said screw head is machined to fit said rotational driver.

28. The device of claim 27, wherein said delivery manifold is removable and is detachably attached to the outside of said screw head.

29. The device of claim 27, wherein said delivery manifold is connected to the interior of said screw head.

30. The device of claim 27, wherein said delivery manifold is connected to said screw head via a butt joint connection.

31. The device of claim 30, wherein said device is capable of receiving a flowable medium through said delivery manifold, and wherein said bone screw is capable of being tightened, prior to hardening of said flowable medium, by the steps of:

i) inserting said rotational driver through said flowable medium within said delivery manifold;

ii) engaging said screw head with the end of said rotational driver; and

iii) tightening said bone screw into final position by rotating said rotational driver.

32. The device of claim 31, wherein said flowable medium comprises bone void filler material, cement, or a pharmaceutical agent.