US-12616457-B2 - Cutting head for tissue collection device

Abstract

An instrument for collecting tissue from a body cavity includes a hollow tubular body. The tubular body has a tubular wall that extends between a proximal-most end and a distal-most end of the tubular body. The tubular wall surrounds a passage that extends to the distal end portion of the tubular body. The tubular body can be a non-bending shaft, or a shaft having an articulating section that allows a portion of the tubular body to articulate relative to the proximal end portion. The distal end portion includes a core drill with a cutting tip. The cutting tip defines a first aperture, a second aperture opposite the first aperture, and a web extending between the first aperture and the second aperture. The web tapers to a drill point at the distal-most end of the tubular body.

Inventors

• Erik Papenfuss

Assignees

• MEDIMETRIX LLC

Dates

Publication Date

20260505

Application Date

20190910

Claims (20)

1. 1 . An instrument for collecting tissue from a body cavity, the collection instrument comprising: a hollow tubular body that defines a longitudinal axis, the tubular body comprising a proximal end portion that terminates at a proximal-most end, a distal end portion that terminates at a distal-most end, and a middle section extending between the proximal end portion and the distal end portion, the middle section having a first end contiguous with and next to the proximal end portion, and a second end contiguous with and next to the distal end portion, the tubular body comprising a tubular wall extending between the proximal-most end and the distal-most end, the tubular wall defining an outer wall surface and an inner wall surface, the tubular wall surrounding a passage that extends to the distal end portion of the tubular body, wherein: the distal end portion comprises a core drill with a cutting tip, the cutting tip defining a first aperture, a second aperture opposite the first aperture, and a web extending between the first aperture and the second aperture, the web tapering to a drill point at the distal-most end of the tubular body, the first aperture and the second aperture each comprise an outline bounded by a linear first edge, a linear second edge, a linear third edge, and a curved fourth edge, the linear first edge and the linear second edge lie in a first plane extending along the longitudinal axis, and the linear third edge and the curved fourth edge lie in a second plane transverse to the longitudinal axis and transverse to the first plane.
2. 2 . The instrument according to claim 1 , wherein the first aperture and the second aperture each comprise an outline bounded entirely by the linear first edge, the linear second edge, the linear third edge and the curved fourth edge.
3. 3 . The instrument according to claim 1 , wherein the first plane is parallel to the longitudinal axis.
4. 4 . The instrument according to claim 1 , wherein the first plane and the second plane intersect at a vertex line.
5. 5 . The instrument according to claim 4 , wherein the linear first edge, the linear second edge, and the vertex line form a triangle.
6. 6 . The instrument according to claim 4 , wherein the linear third edge, the curved fourth edge, and the vertex line form a pie-shape enclosed by two straight sides and one curved side.
7. 7 . The instrument according to claim 1 , wherein the first aperture is defined by a first gash having a first gash angle and the second aperture is defined by a second gash having a second gash angle.
8. 8 . The instrument according to claim 7 , wherein the first gash angle and second gash angle are each 30 degrees relative to the longitudinal axis.
9. 9 . The instrument according to claim 7 , wherein the first gash is defined by a first gash sweep, and the second gash is defined by a second gash sweep.
10. 10 . The instrument according to claim 9 , wherein the first gash sweep and the second gash sweep are each 125 degrees relative to the longitudinal axis.
11. 11 . The instrument according to claim 1 , wherein the first aperture is defined by a first lip having a first lip relief and the second aperture is defined by a second lip having a second lip relief.
12. 12 . The instrument according to claim 11 , wherein the first lip relief and second lip relief are each 15 degrees.
13. 13 . The instrument according to claim 1 , wherein the web comprises an inner web surface, an outer web surface, and a web thickness between the inner web surface and the outer web surface, the web thickness at the drill point being 0.035 in.
14. 14 . The instrument according to claim 1 , wherein the cutting tip defines an outer drill point angle and an inner core angle.
15. 15 . The instrument according to claim 14 , wherein the outer drill point angle and the inner core angle are equal.
16. 16 . The instrument according to claim 15 , wherein the outer drill point angle and the inner core angle are 118 degrees.
17. 17 . The instrument according to claim 1 , wherein the drill point comprises a linear edge.
18. 18 . The instrument according to claim 17 , wherein the linear edge has a length of 0.015 in.
19. 19 . The instrument according to claim 1 , wherein the passage terminates at the proximal end to define a proximal opening in the tubular body, and terminates at the distal end to define the first and second apertures.
20. 20 . The instrument according to claim 1 , wherein the tubular body comprises an articulating section that allows a portion of the tubular body to articulate relative to the proximal end portion.

Description

This application is a U.S. National Phase application of PCT International Application No. PCT/US2019/050310, filed Sep. 10, 2019, which is incorporated by reference herein. FIELD The present disclosure relates generally to instrumentation for collecting tissue from a body cavity, and more particularly to a cutting head for collecting tissue in a preserved state from bone. BACKGROUND Bone marrow, which is produced and stored inside bone, can be harvested and used for different purposes, including the treatment of congenital defects and diseases, and reconstruction of bone. Bone marrow contains useful components, including hematopoietic stem cells and blood cells. Conventional methods for harvesting bone marrow have historically relied on the use of needles. A needle is advanced through the patient's skin and the wall of a bone until the needle tip enters into the bone cavity containing the marrow. Typically, the needle is advanced into the donor's pelvis, but the needle can also be inserted into other bones. Once the needle penetrates into the bone cavity, the needle advances in a linear path, and the marrow is harvested by aspiration. Bone marrow harvesting by aspiration often yields a relatively small amount of stem cells because the concentration of stem cells at specific locations is low. To harvest a sufficient amount of marrow and stem cells, the physician must draw a significant volume of marrow which is greater than can be drawn from a single aspiration at one location. Therefore, to collect a sufficient volume of marrow and stem cells, the needle must be inserted into the bone at multiple locations within the bone cavity to draw bone marrow from different areas. This requires multiple punctures through the outer cortex and into the bone cavity to collect the required volume of marrow. Multiple punctures can be time consuming and labor intensive for physicians performing the harvesting. In addition, multiple punctures cause a great deal of pain to the donor and require a long recovery time after the patient is taken off of general anesthesia. U.S. Pat. No. 7,462,181 to Daniel Kraft and James Hole (hereinafter, “the '181 Patent”) describes an alternative device for aspirating bone marrow or tissue from a bone cavity. Rather than using a rigid needle that proceeds linearly through bone, the device includes a thin hollow needle that is flexible enough to move through the bone marrow cavity in a non-linear fashion. By advancing the needle in a non-linear path, the needle can access different locations in the bone from a single entry point. Although the flexible needle in the '181 Patent can, in theory, allow more marrow to be collected from a single entry point, collection is only done by aspiration. The flexible needle does not allow bone marrow or tissue to be collected by “coring”, in which a core of marrow is removed from the bone cavity in an undisturbed state. Aspiration tends to mix stem cells with blood and other components as the material is collected under suction. This mixing can dilute the concentration of stem cells at a collection point. Flexible needles are also prone to breakage during procedures due to their very small diameter. This propensity for breakage often requires the use of accessories to reinforce the needle during a harvesting procedure. For example, the '181 Patent describes embodiments that utilize a stylet inside the flexible needle when the needle is advanced into the bone marrow. Stylets provide aspiration needles with additional strength and rigidity during advancement through the marrow space. The need for stylets and other accessories increases the number of items that must be sterilized and handled with aspiration needles during a harvesting procedure. Moreover, flexible hollow needles offer few options for controlling the amount of bending or pivot motion along the length of the needle. Flexible needles with uniform cross sections are generally flexible along their entire length. This may not be desirable in applications where only a section of the shaft needs to bend, while the remainder of the shaft should remain rigid. Flexible needles also lack features to assist in cutting through dense cortical bone or shaving bone. U.S. Pat. No. 8,852,119 to Kortney Wawrziniak, et al. (hereinafter, “the '119 Patent”) describes another device for harvesting bone marrow from a bone cavity. The device includes a flexible needle and a trocar with a cannulated shaft. The cannulated shaft of the trocar can be driven into bone to provide an access path into the bone. The cannulated shaft is also configured to receive the flexible needle after being driven into the bone. Once the needle is advanced into a target bone, a receptacle is coupled to the needle to aspirate bone marrow through the needle. The needle can have both a rigid section and a flexible portion extending distally from the rigid section. The flexible portion of the needle is defined by a continuous groove that extends