Cutting Apparatus for Bioprocessing Bone
A bone cutting assembly includes a manually actuated upper cutting element that carries a plurality of cutting blades configured to cut through frozen bone segments. A lower cutting element supports a bone segment to be cut and can include cutting blades aligned with the cutting blades of the upper cutting assembly. A pivoting linkage or a rack and pinion arrangement can be provided between the upper cutting element and a manually operated handle to provide sufficient mechanical advantage or leverage to allow an operator to manually cut through the bone.
This application is a utility filing from and claims priority to co-pending application No. 62/670,283, filed on May 11, 2018, the entire disclosure of which is incorporated herein by reference.
BACKGROUNDThe present disclosure concerns an apparatus useful for recovering live bone marrow.
Bone marrow for clinical purposes is harvested from HLA matched siblings or optimally matched unrelated donors (MUD). Other graft sources are mismatched haploidentical related or unrelated donors and umbilical cord blood (CB). When transplanted into patients with certain diseases, the hematopoietic stern cells (HSCs) in the donor bone marrow engraft in the patient and reconstitute immune and hematopoietic systems.
Bone marrow is also a source for mesenchymal stromal/stem cells (MSCs) which are self-renewing, multipotent progenitor cells with multilineage potential to differentiate into cell types of mesodermal origin, such as adipocytes, osteocytes, and chondrocytes. In addition, MSCs can migrate to sites of inflammation and exert potent immunosuppressive and anti-inflammatory effects through interactions between lymphocytes associated with both the innate and adaptive immune system.
Currently bone marrow is typically collected through a hole created in the outer bone with a trocar needle. A bone marrow aspiration needle is then introduced into the hole and a syringe is used to draw the marrow out of the bone. The syringes are then removed from the sterile field and connected to a collection bag containing anticoagulants. The marrow is pushed into the bag. This step is repeated many times, typically in both pelvic bones, and can often result in contamination of the aspirate.
Once recovered, bone marrow can be cryopreserved and banked for future use. This is typically done using a cryoprotectant agent (CPA) such as dimethyl sulfoxide (DMSO) with or without a carbohydrate, such as hydroxyethyl starch (HES), in a balanced electrolyte solution with or without a protein supplement, such as human or animal serum, platelet lysate, or albumin and with or without added growth factors. Cells are cooled slowly (−1° C. to −5° C./min) down to an intermediate, low sub-zero temperature and then transferred to final storage in vapor or liquid nitrogen.
Optimal cryopreservation techniques for bone marrow should be effective when applied to the whole tissue, with the idea that stem cells would be isolated following thawing, assuming adequate permeation of the cells to the CPA. Immediate cryopreservation of tissues is more practical than direct primary isolation of stem cells, which requires further processing and expense.
It is often optimal to cryopreserved whole bone to be subsequently processed for extraction of the bone marrow. To adequately cryopreserve bone for subsequent post thaw processing, the bone must be cooled very slowly (with cryoprotective agents) e.g. with cooling rates of −0.1° to −4.0° C. per min. However, to successfully recover live cells rapid warming is required (e.g. >50° C./min). While cooling rates can readily be applied in a slow manner, warming large volumes of bone quickly is problematic. Consequently, there is a need for an apparatus that can reduce the whole cryopreserved bone to smaller pieces that can then be placed into a warming medium immediately to allow rapid thaw.
SUMMARY OF THE DISCLOSURETo enable cryopreservation of whole bone and facilitate subsequent processing of the bone, an apparatus is provided which can be used to process the bone and recover bone marrow to a cellular suspension prior to cryopreservation, or to enable the cryopreservation of whole bone to be subsequently processed. The apparatus allows either a fresh bone or a cryopreserved bone to be cut into pieces appropriately sized for further fresh processing or rapid thawing. In one embodiment, the apparatus is manually operated with a linkage arrangement or a lever arm and rack and pinion arrangement providing a mechanical advantage or leverage sufficient to cut through bone with only manual effort.
The present disclosure provides a bone cutting apparatus that comprises a lower cutting element configured to support a bone segment to be cut and an upper cutting element including a plurality of cutting blades facing the lower cutting element. A frame supports the upper cutting element above the lower cutting element for movement toward and away from the lower cutting element. The apparatus is provided with a manually operable handle and a force transmission mechanism connecting the handle to the upper cutting element to move the upper cutting element toward the lower cutting element with sufficient force to cut through the bone segment supported on the lower cutting element.
In one embodiment, the bone cutting apparatus includes upper and lower cutting elements, each with aligned cutting blades, in which the upper cutting element is pushed toward the stationary lower cutting element to cut through a bone segment positioned between the two elements. The upper cutting element is carried by a shaft that is connected to a linkage, that is in turn connected to a handle. The handle is pivotably mounted to the cutting apparatus so that pushing the handle downward pushes the upper cutting element downward with a mechanical advantage derived by the configuration of the handle and linkage.
In another embodiment, the upper cutting element is pushed by a handle applying force through a rack and pinion arrangement. A ratchet and pawl arrangement control the direction of movement of the rack that carries the upper cutting element. In this embodiment, the upper cutting element includes replaceable blades and a stationary lower cutting tray that supports the bone segment to be cut. A collection container is disposed beneath the lower cutting tray to receive the bone fragments at the completion of the cutting operation.
For the purposes of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiments illustrated in the drawings and described in the following written specification. It is understood that no limitation to the scope of the disclosure is thereby intended. It is further understood that the present disclosure includes any alterations and modifications to the illustrated embodiments and includes further applications of the principles disclosed herein as would normally occur to one skilled in the art to which this disclosure pertains
An apparatus 10 is provided, as shown in
The upper shroud 32 can include a plurality of vertical slots 34 that can receive a projection 41a on each of the cutting blades 41 of the upper cutting element 30. The projections 41a on the blades can thus guide the upper shroud 32 as it is moved from its uppermost position shown in
The upper cutting element 30 is carried by a shaft 35 that extends through and is guided by a bore 36 in the intermediate plate 16. The upper end of the shaft 35 is pivotably connected to a linkage 40 that is pivotably connected to a handle 42. The handle 42 includes a hand grip portion 42a that is mounted or affixed at a generally perpendicular angle to a plate 42b, as best seen in
The upper cutting element 30 can include a piston body 44 (
The lower cutter element 22 can include a base 47 onto which the cutting blades 40 are mounted or affixed. As with the cutting blades 41, the cutting blades 40 can be individually mounted to the base 47 or can be part of a cutting blade component. The base 47 is configured to be seated within a cavity or recess 48 defined in the bottom plate 11, as shown in
Several different configurations of cutting blades 40, 41 may be incorporated into the respective lower and upper cutter elements 22, 30. In one embodiment, four blades defining a “+” configuration can be provided as shown in
In an alternative embodiment shown in
In specific embodiments, the upper and lower cutter elements can have a combined cutting height of about 2.5-3.0 inches in order to cut through bone segments B of the same height. The cutting blades can have a thickness of about 0.12 inches, tapering to a sharp point. In the embodiment of
A bone cutting apparatus 50 according to another embodiment of the disclosure is shown in
The pinion shaft 65 includes a ratchet gear 70 that is engaged by a pawl 71, as shown in
The ratchet gear 70, and thus the pinion shaft 65, are manually rotated in the clockwise direction (as shown in
In accordance with this embodiment, the bone cutting assembly 50 is provided with an upper cutting assembly 80 and a lower cutting assembly 82 (
The upper blade mounting plate 84 is configured to receive a removable and replaceable upper cutter base 92, as shown in
As shown in
The upper cutting assembly 80 is driven toward the lower cutting assembly 82 to cut a bone segment B positioned between the two assemblies. The lower cutting assembly includes a cutting tray 110 that is removably mounted in the base 55, as illustrated in
A blade assembly assist component 140 is provided for mounting the upper cutter base 92 to the blade mounting plate 84, as shown in
The bone cutting apparatus 50 can be used to cut a bone segment B into several fragments, even if the bone segment is frozen. The segment B is placed on the cutting tray 110 of the lower cutting assembly 82, as shown in
The cutting tray 110 can be configured so that the bone fragments fall into the collection container 115 positioned within the cavity 113 in the base 55 beneath the upper cutting assembly. For instance, the cutting tray can be configured like the base 47′ shown in
The bone cutting apparatuses 10, 50 are configured to cut through a bone segment, such as the bones of the pelvis, the long bones and vertebral bodies. The force required to cut through such bone is typically 800-900 lbf. The apparatuses of the present disclosure provide a force transmission mechanism from the user-operated handles 42, 74 to the upper cutting assemblies 20, 80. The force transmission mechanisms allow the typical operator to generate up to 1000 lbf by applying less than 50 lbf to the handle, which is well within the capability of most operators.
The present disclosure should be considered as illustrative and not restrictive in character. It is understood that only certain embodiments have been presented and that all changes, modifications and further applications that come within the spirit of the disclosure are desired to be protected.
Claims
1. A bone cutting apparatus comprising:
- a lower cutting element configured to support a bone segment to be cut;
- an upper cutting element including a plurality of upper cutting blades facing said lower cutting element;
- a frame supporting said upper cutting element above said lower cutting element for movement toward and away from said lower cutting element;
- a manually operable handle; and
- a force transmission mechanism connecting said handle to said upper cutting element to move said upper cutting element toward said lower cutting element with sufficient force to cut through the bone segment supported on said lower cutting element.
2. The bone cutting apparatus of claim 1, wherein said lower cutting element includes a plurality of lower cutting blades facing said upper cutting element and corresponding to said plurality of upper cutting blades.
3. The bone cutting apparatus of claim 1, wherein said plurality of upper cutting blades are arranged in a radial pattern.
4. The bone cutting apparatus of claim 3, wherein the plurality of upper cutting blades are separated from each other by a uniform angle in said radial pattern.
5. The bone cutting apparatus of claim 4, wherein the plurality of upper cutting blades includes four cutting blades separated by 90 degrees.
6. The bone cutting apparatus of claim 4, wherein the plurality of upper cutting blades includes six cutting blades separated by 60 degrees.
7. The bone cutting apparatus of claim 4, wherein the plurality of upper cutting blades includes eight cutting blades separated by 45 degrees.
8. The bone cutting apparatus of claim 1, wherein said plurality of upper cutting blades define a cutting edge configured to cut through the bone segment, the cutting edge of at least a number of said plurality of upper cutting blades being perpendicular to the direction of movement of said upper cutting element.
9. The bone cutting apparatus of claim 1, wherein said plurality of upper cutting blades define a cutting edge configured to cut through the bone segment, the cutting edge of at least a number of said plurality of upper cutting blades being at a non-perpendicular angle relative to the direction of movement of said upper cutting element
10. The bone cutting apparatus of claim 1, wherein said lower cutting element includes a plurality of slots corresponding to said plurality of upper cutting blades, each of said slots configured to receive a portion of a corresponding one of said upper cutting blades when said upper cutting element is moved toward said lower cutting element.
11. The bone cutting apparatus of claim 1, further comprising a shroud configured to encircle the upper cutting element and the bone segment to be cut when the upper cutting element is moved toward the lower cutting element.
12. The bone cutting apparatus of claim 1, wherein: said frame includes; said force transmission mechanism includes:
- a base supporting said lower cutting element;
- a plurality of vertical columns supported on said base;
- a top plate supported at the top of said plurality of columns; and
- an intermediate plate supported by said plurality of columns between said base and said top plate; and
- a plate connected to the manually operated handle, the plate pivotably mounted at one end of said plate to said top plate to pivot downward toward said lower cutting element;
- a linkage pivotably mounted at one end of the linkage to an end of said plate opposite said one end; and
- a shaft pivotably connected at an upper end thereof to an end of said linkage opposite said one end, and connected at a lower end thereof to said upper cutting element, said shaft slidably supported between said upper end and said lower end by said intermediate plate.
13. The bone cutting apparatus of claim 1, wherein: said frame includes; said force transmission includes;
- a base plate supporting said lower cutting element;
- a vertical post supported at a lower end of the post on said base plate;
- a mounting element supported at an upper end of said vertical post; and
- a gear rack slidably supported by said mounting element for vertical movement toward and away from said lower cutting element, said gear rack carrying said upper cutting element;
- a pinion gear rotatably supported within said mounting element in meshed engagement with said gear rack; and
- pinion shaft carrying said pinion gear and connected to said manually operable handle, said handle configured to rotate said pinion shaft with said pinion gear on downward movement of said handle, whereby rotation of said pinion gear drives said gear rack and said upper cutting element downward.
14. The bone cutting apparatus of claim 13, wherein said upper cutting element includes:
- an upper mounting plate connected to said pinion shaft;
- an upper cutter base removably mountable to said upper mounting plate facing said lower cutting element; and
- a number of cutting blades carried by said upper cutter base facing said lower cutting element.
15. The bone cutting apparatus of claim 14, wherein said frame includes at least two guide posts and said upper mounting plate is slidably guided by said at least two guide posts for vertical movement toward and away from said lower cutting element.
16. The bone cutting apparatus of claim 14, wherein said number of cutting blades includes replaceable cutting blades that are removably mounted to said upper cutter base.
17. The bone cutting apparatus of claim 16, wherein said replaceable cutting blades and said upper cutter base include a T-slot and mating rib.
18. The bone cutting apparatus of claim 1, wherein said lower cutting element includes a lower base defining a collection cavity and a cutting tray above said collection cavity configured to support the bone segment, said cutting tray configured for bone fragments to pass into said collection cavity.
19. The bone cutting apparatus of claim 18, further comprising a collection container removably disposed within said collection cavity beneath said cutting tray.
Type: Application
Filed: May 11, 2019
Publication Date: Nov 14, 2019
Inventors: Erik J. Woods (Carmel, IN), Brian Johnstone (Fishers, IN), Joseph Ingalls (Westfield, IN)
Application Number: 16/409,808