Bone marrow needle assembly

• US 5,368,046 A
• Filed: 03/24/1993
• Issued: 11/29/1994
• Est. Priority Date: 09/09/1992
• Status: Expired due to Term

• Current Assignee: Covidien AG (Medtronic Plc)
• Original Assignee: Symbiosis Corporation (Boston Scientific Corporation)
• Inventors: Weisenborn, Alan L., Scarfone, Frank A., Turkel, David
• Primary Examiner(s): HINDENBURG, MAX F
• Application Number:
  US08/036,474
• Time in Patent Office: 615 Days
• Field of Search: 128/751, 128/753, 128/754, 604/117
• US Class Current: 600/567
• CPC Class Codes: A61B 10/025 for taking bone, bone marrow or cartilage samples
• CPC Class Codes: A61B 2010/0258 Marrow samples

Abstract

A bone marrow needle assembly includes a cannula housing supporting a cannula having a sharp distal end. The cannula housing is provided with a central throughbore in fluid communication with the cannula and with an ergonomic handle having a curved distal surface. A female luer lock fluid coupling is provided in the housing at the proximal end of the throughbore and within the periphery of the curved handle. A trocar is located within the cannula and extends through the luer lock and the throughbore. The trocar has a cap which extends over the luer lock and is rounded so that a substantially continuous rounded surface is presented by the semi-circular handle and the trocar cap. The distal end of the housing is provided with a threaded portion which receives a locking nut and a depth stop. The depth stop has a mating interior threaded bore which couples with the threaded distal portion of the housing so that the depth stop may be rotated to adjust the effective piercing length of the cannula. The locking nut is rotated into a locking position against the depth stop to secure the depth stop in a selected position.

Claims

1. A bone marrow needle assembly, comprising:

a) a cannula housing having a proximal end, a distal end, and forming a central throughbore, said distal end having an outer surface having a threaded portion, said proximal end of said cannula housing being formed as a handle having a proximal outer surface which is curved in a convex manner along an arc having a first radius and a distal outer surface which is bowed in a convex manner along an arc having a second radius, said first radius being smaller than said second radius;

b) a locking fluid coupling means for mating with one of a fluid injection means and a fluid aspiration means, said locking fluid coupling means being in fluid communication with said central throughbore, said locking fluid coupling means located at said proximal end of said cannula housing;

c) a locking nut threadably coupled to said threaded portion;

d) a depth stop means having an interior threaded bore threadably coupled to said threaded portion; and

e) a cannula mounted in said throughbore of said cannula housing, wherein

said locking nut is located proximal of said depth stop means on said threaded portion such that rotation of said depth stop about said threaded portion effects a longitudinal movement of said depth stop relative to said housing and rotation of said locking nut effects a longitudinal movement of said locking nut relative to said depth stop means whereby said depth stop means is substantially locked in position by said locking nut when said locking nut is moved against said depth stop means.

2. A bone marrow needle assembly according to claim 1, further comprising:

f) a trocar which is insertable through said throughbore into said cannula; and

g) a trocar cap coupled to said trocar and having a first locking means, wherein

said proximal end of said cannula housing has a second locking means for engaging said first locking means to lock said trocar cap in position whereby said trocar is fixed inside said cannula.

3. A bone marrow needle assembly according to claim 2, wherein:

a proximal end of said handle has a substantially U-shaped central recess and said locking fluid coupling means is located within said central recess.

4. A bone marrow needle assembly according to claim 3, wherein:

said trocar cap has a distal end which is substantially circular in cross-section, and

said U-shaped central recess has arcuate lateral walls which receive said trocar cap.

5. A bone marrow needle assembly according to claim 2, wherein:

said trocar cap forms an internal hollow which receives said locking fluid coupling means.

6. A bone marrow needle assembly according to claim 5, wherein:

said first locking means comprises a bayonet socket in said trocar cap; and

said second locking means comprises a support with a lateral bayonet pin which mates in said bayonet socket.

7. A bone marrow needle assembly according to claim 2, wherein:

said trocar has an L-shaped proximal end which is insert molded in said trocar cap.

8. A bone marrow needle assembly according to claim 1, wherein:

said locking fluid coupling means is substantially within a periphery of the curve of said proximal outer surface of said handle.

9. A bone marrow needle assembly according to claim 1, wherein:

said handle is tapered from a proximal end to a distal end thereof,

said handle is tapered from a center portion to lateral end portions thereof, and

said handle has smooth rounded edges.

10. A bone marrow needle assembly according to claim 1, wherein:

said locking fluid coupling means is a female luer lock.

11. A bone marrow needle assembly according to claim 1, wherein:

said cannula has a flared proximal end which is insert and molded in said cannula housing.

12. A bone marrow needle assembly according to claim 11, wherein:

said flared proximal end flares at an angle of approximately forty-five degrees, and

said flared proximal end is split into two portions.

13. A bone marrow needle assembly comprising:

a) a cannula housing having a proximal end, a distal end, and central throughbore, said distal end having an outer surface having a threaded portion, said proximal end of said cannula housing being formed as a handle having a proximal outer surface which is curved in a convex manner along an arc having a first radius and a distal outer surface which is bowed in a convex manner along an arc having a second radius, said first radius being smaller than said second radius;

b) a cannula mounted in said throughbore of said cannula housing;

c) a trocar which is insertable through said throughbore into said cannula;

d) a trocar cap coupled to said trocar, with said trocar cap having a first locking means, wherein said cannula has a proximal end having a second locking means for engaging said first locking means to lock said trocar cap in position whereby said trocar is fixed inside said cannula;

e) a locking fluid coupling means in fluid communication with said central throughbore, said locking fluid coupling means located at said proximal end of said cannula housing;

f) a locking nut threadably coupled to said threaded portion of said cannula housing; and

g) a depth stop means having an interior threaded bore threadably coupled to said threaded portion of said cannula housing, wherein

said locking nut is located proximal of said depth stop means on said threaded portion such that rotation of said depth stop means about said threaded portion effects a longitudinal movement of said depth stop relative to said housing and rotation of said locking nut effects a londgitudinal movement of said locking nut relative to said depth stop whereby said depth stop is substantially locked in position by said locking nut when said locking nut is moved against said depth stop.

14. A bone marrow needle assembly according to claim 13, wherein:

said proximal outer surface of said handle forms a central recess, and

said locking fluid coupling means is located within said recess and substantially within a periphery of said curve of said outer surface of said handle.

15. A bone marrow needle assembly according to claim 14, wherein

said trocar cap has a rounded top portion, and said rounded top portion and said curved proximal outer surface of said proximal end of said cannula housing form a substantially continuous rounded outer surface for said bone marrow needle assembly.

16. A bone marrow needle assembly comprising:

a) a cannula housing having a proximal end, a distal end, and forming a central throughbore, said distal end having an outer surface having a threaded portion, said proximal end of said cannula housing being formed as a handle having a proximal outer surface which is curved in a convex manner along an arc having a first radius and a distal outer surface which is bowed in a convex manner along an arc having a second radius, said first radius being smaller than said second radius;

b) a cannula mounted in said throughbore of said cannula housing;

c) a trocar which is insertable through said throughbore into said cannula;

d) a trocar cap coupled to said trocar, with said trocar cap having a first locking means, wherein said cannula has a proximal end having a second locking means for engaging said first locking means to lock said trocar cap in position whereby said trocar is fixed inside said cannula;

e) a locking fluid coupling means in fluid communication with said central throughbore, said locking fluid coupling means located at said proximal end of said cannula housing;

f) a depth stop means having an interior threaded bore threadably coupled to said threaded portion of said cannula housing, wherein

said proximal end of said cannula housing has a central recess therein, and

said locking fluid coupling means is located within said recess, and

said trocar cap has a rounded top portion, and said rounded top portion and said proximal outer surface of said proximal end of said cannula housing form a substantially continuous rounded outer surface for said bone marrow needle assembly.

17. A method of preparing a bone marrow needle assembly for insertion into a bone of a patient, said bone marrow needle assembly having a cannula housing having a proximal end, a distal end, and a central throughbore, said proximal end of said cannula housing being formed as a handle having a proximal outer surface which is curved in a convex manner along an arc having a first radius and a distal outer surface which is bowed in a convex manner along an arc having a second radius, said first radius being smaller than said second radius, said distal end having a first threaded means, a fluid coupling means for mating with one of a fluid injection means and a fluid aspiration means, said fluid coupling means being in fluid communication with said central throughbore, said fluid coupling means located at said proximal end of said cannula housing, a depth stop means having a second threaded means threadably coupled to said first threaded means, a locking means for locking said depth stop means in place, and a cannula mounted in said throughbore of said cannula housing, said method comprising:

a) determining a desired needle length;

b) rotating said depth stop means relative to said first threaded means until said cannula extends beyond said depth stop means by said desired needle length; and

c) rotating said locking means into locking engagement with said depth stop means in order to lock said depth stop means in place with said cannula extending beyond said depth stop means by said desired needle length.

18. A bone marrow needle assembly, comprising:

a) a cannula housing having a proximal end, a distal end, and forming a central throughbore;

b) a locking fluid coupling means for mating with one of a fluid injection means and a fluid aspiration means, said locking fluid coupling means being in fluid communication with said central throughbore, said locking fluid coupling means located at said proximal end of said cannula housing;

c) a cannula mounted in said throughbore of said cannula housing and being in fluid communication with said locking fluid coupling means, wherein

said proximal end of said cannula housing is formed as a handle having a proximal outer surface which is curved in a convex manner along an arc having a first radius and a distal outer surface which is bowed in a convex manner along an arc having a second radius, said first radius being smaller than said second radius.