Patent Publication Number: US-2022226005-A1

Title: Tissue collection and delivery device and methods of use thereof

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of co-pending U.S. application Ser. No. 16/346,949, entitled TISSUE COLLECTION AND DELIVERY DEVICE AND METHODS OF USE THEREOF, which in turn is the U.S. national phase entry under 35 U.S.C. § 371 of International Application No. PCT/US2019/012870, filed Jan. 9, 2019, which in turn claims priority to and benefit of U.S. Provisional Application No. 62/622,247, filed Jan. 26, 2018, the contents of which are incorporated herein by reference in their entirety for all purposes. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to tissue harvesting and, more particularly, to a device for collecting autologous tissue from a surgical site and delivering the collected material where desired. 
     BACKGROUND 
     Articular cartilage is an avascular tissue which lines the ends of the bones and facilitates frictionless movement of the joints, such as the knee joint. Damage to cartilage caused by injury or disease does not heal on its own, and the pathological changes resulting from this damage can be a source of pain and limited mobility to a patient, and can have a significant detrimental impact on the patient&#39;s quality of life. Additionally, over time, cartilage lesions are likely to degenerate into osteoarthritis and the need for a total joint replacement. 
     In some cases, tissue harvesting techniques can be used to treat cartilage lesions and postpone or obviate the need for a joint replacement. These techniques enable a surgeon to purify a unique population of repair cells from the patient&#39;s tissues, such as synovial or adipose tissue, and deliver the cells back into the patient&#39;s joint to stimulate cartilage repair. The repair cells are harvested arthroscopically from a site local to the defect (i.e. within the joint), and repair cells of a desired size are isolated, for example, by filtering. The isolated cells are typically mixed with a biocompatible “gluing” agent and the mixture of the agent and the harvested cells is then provided to the repair site. The use of autologous tissue is particularly desirable as it substantially reduces the potential for an immunogenic host response and tissue rejection. 
     Various tissue harvesting techniques for treating cartilage are known in the art. Some examples include mosaicplasty, in which plugs of cartilage and bone are harvested from low weight-bearing regions of the joint and transplanted into the defect; or autologous chondrocyte implantation (ACI), in which cells are isolated and expanded from a cartilage biopsy and re-introduced into the defect in a second procedure. However, some of these techniques, like ACI, involve separate surgical procedures that occur on two different days, which may be weeks apart. Even for single surgery techniques, clinical results suggest that the long-term biochemical and biomechanical properties of the reparative tissue are generally not ideal. 
     SUMMARY 
     Described herein are low cost, simple, one-surgery systems and methods for harvesting autologous tissues from a patient and delivering them into another area that requires repair. The system of this disclosure harvests autologous tissue, minces it into fragments that are visible and measureable when filtered, and delivers a portion of the tissue back into the patient. Advantageously, this is accomplished without the need to directly touch the tissue, thus eliminating the risk of disease transmission and immune response associated with such treatment. During the same surgical procedure, the isolated cut tissue can be loaded into, or mixed with, an appropriate carrier before introduction into the repair site. The systems and methods of this disclosure advantageously reduce the need for multiple surgeries and also facilitate improved long-term recovery outcomes by efficiently harvesting and implanting autologous tissue during a single surgical procedure. 
     Further examples of the systems and methods of this disclosure may include one or more of the following, in any suitable combination. 
     In examples, the tissue collection assembly of this disclosure includes a resection system having a handpiece with a proximal end, a distal end, and a passageway therethrough. The resection system also includes a cannulated shaft attached to the handpiece in fluid communication with the passageway. A distal end of the shaft has a cutting end. The tissue collection assembly also includes a filter assembly removeably attached to the handpiece in fluid communication with the cannulated shaft. The filter assembly includes a housing allowing direct visualization of an internal volume of the housing, a filter removeably disposed within the internal volume of the housing for collecting tissue on a surface of the filter, and a compressor extendable through the internal volume of the housing for compressing the collected tissue. The filter assembly is coupleable with a delivery device to deliver the collected tissue to a repair site. 
     In other examples, the handpiece further includes rigid tubing and a barb in fluid communication with the filter assembly. The compressor has an inlet for removeable attachment to the barb. The housing also includes a removeable outlet for attachment to a vacuum source. The filter is coupled to the outlet such that the filter and the outlet are removeable from the housing simultaneously. In examples, the housing further includes a shearing member slidably disposed around the filter for removing the collected tissue from the filter. In examples, the resection system also includes a flexible shield adjacent the cutting end of the shaft. In examples, the handpiece is a motorized drive unit having at least one internal structure to prevent contamination of the collected tissue by the handpiece. In examples, the at least one internal structure is a flow diverter or a sleeve integrated with the passageway of the handpiece. In further examples, the tissue collection assembly includes one or more deformable wires for mixing the collected tissue with a biocompatible agent. The wires are attached to the compressor or to the plunger. In examples, the filter is a hollow, tubular filter, and the surface of the filter comprises holes in communication with an interior of the filter. 
     Examples of the tissue collection assembly and delivery device combination of this disclosure include a tissue collection assembly with a resection system having a handpiece with a proximal end, a distal end, and a passageway therethrough. The resection system also includes a cannulated shaft attached to the handpiece in fluid communication with the passageway. A distal end of the shaft has a cutting end. The tissue collection assembly also includes a filter assembly removeably attached to the handpiece in fluid communication with the cannulated shaft. The filter assembly includes a housing allowing direct visualization of an internal volume of the housing, a filter removeably disposed within the internal volume of the housing for collecting tissue on a surface of the filter, and a compressor extendable through the internal volume of the housing for compressing the collected tissue. A delivery device is coupleable to a coupling portion of the housing for delivering the collected tissue to a repair site. In further examples, the combination includes a plunger insertable through the compressor and a channel of the delivery device. The combination also includes an actuator for advancing the plunger within the channel and a mechanism for controlling the relative motion between the compressor and the plunger through a portion of the housing. The mechanism is configured to prevent the advancement of the plunger through the housing until the compressor is stopped from advancing through the housing. 
     Examples of the method of collecting and delivering tissue to a repair site of this disclosure include contacting a blade of a tissue collection assembly with tissue and cutting the tissue with a cutting end of the blade to create tissue fragments. The method also includes aspirating fluid and the tissue fragments through the blade to a filter assembly. The filter assembly includes a housing allowing direct visualization of an internal volume of the housing, the housing in fluid communication with the blade, a filter removeably disposed within the internal volume of the housing for collecting the tissue fragments on a surface of the filter, a compressor extendable through the internal volume of the housing for compressing the tissue fragments, and a shearing member slidably disposed around the filter for removing the collected tissue from the filter. The method also includes separating the tissue fragments having a pre-selected size from the fluid using the filter and detaching the filter assembly from the blade. In examples, the method also includes removing the filter from housing, thereby causing the shearing member to shear the tissue fragments from the surface of the filter, and coupling the filter assembly to a delivery device. Finally, examples of the method include inserting a plunger through the filter assembly and the delivery device to deliver the tissue fragments to a repair site. 
     Further examples of the method include extending the compressor within the housing to compress the tissue fragments such that a volume of the tissue fragments is measureable by direct visualization. In examples, the method also includes injecting a biocompatible agent into the housing and rotating one or more deformable wires attached to the compressor or the plunger to mix the tissue fragments and the agent. In examples, the method also includes actuating an actuator on the delivery device to advance the plunger within a channel of the delivery device. 
     Other examples of a resection system of this disclosure include a handpiece having a proximal end, a distal end, and a passageway therethrough. Examples of the resection system also have a cannulated shaft attached to the handpiece in fluid communication with the passageway. A distal end of the shaft has a cutting end. In examples, the resection system also includes a filter removeably disposed within the shaft between the handpiece and the cutting end for collecting tissue on a surface of the filter. 
     These and other features and advantages will be apparent from a reading of the following detailed description and a review of the associated drawings. It is to be understood that both the foregoing general description and the following detailed description are explanatory only and are not restrictive of aspects as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure will be more fully understood by reference to the detailed description, in conjunction with the following figures, wherein: 
         FIG. 1  illustrates an exemplary tissue collection assembly of this disclosure; 
         FIGS. 2A and 2B  are detailed views of the cutting end of the tissue collection assembly of  FIG. 1 ; 
         FIGS. 3A-G  are detailed views of various examples of the handpiece and blade of the tissue collection assembly of  FIG. 1 ; 
         FIGS. 4A and 4B  are detailed views of an exemplary filter assembly of the tissue collection assembly of  FIG. 1 ; 
         FIGS. 5A-C  illustrate removal of the filter from the filter assembly of  FIG. 4A ; 
         FIGS. 6A-C  are detailed views of exemplary mixing elements of the tissue collection assembly of  FIG. 1 ; 
         FIGS. 7A and 7B  illustrate an exemplary tissue collection and delivery device of this disclosure in an exploded view ( FIG. 7A ) and an assembled view ( FIG. 7B ); 
         FIG. 7C  illustrates an alternative example of the delivery device of  FIG. 7A ; 
         FIGS. 8A and 8B  are detailed views of an actuator and plunger interface of the device of  FIG. 7B ; 
         FIGS. 9A-C  and  FIGS. 11A-C  are detailed views of the control mechanism between the plunger and the compressor of  FIG. 7B ; 
         FIGS. 10A and 10B  illustrate alternative examples of the mixing elements of  FIG. 6A ; 
         FIGS. 12A and 12B  illustrate an exemplary method of using the tissue collection and delivery device of  FIG. 7A ; 
         FIG. 13  illustrates an alternative example of the filter of  FIG. 4A ; 
         FIGS. 14A and 14B  illustrate another example of the filter of  FIG. 4A ; and 
         FIGS. 15A-C  illustrate another example of the mixing elements of  FIGS. 10A-C  and the control mechanism of  FIGS. 9A-C . 
     
    
    
     DETAILED DESCRIPTION 
     In the description that follows, like components have been given the same reference numerals, regardless of whether they are shown in different examples. To illustrate example(s) in a clear and concise manner, the drawings may not necessarily be to scale and certain features may be shown in somewhat schematic form. Features that are described and/or illustrated with respect to one example may be used in the same way or in a similar way in one or more other examples and/or in combination with or instead of the features of the other examples. 
     As used in the specification and claims, for the purposes of describing and defining the invention, the terms “about” and “substantially” are used to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. The terms “about” and “substantially” are also used herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue. “Comprise,” “include,” and/or plural forms of each are open ended and include the listed parts and can include additional parts that are not listed. “And/or” is open-ended and includes one or more of the listed parts and combinations of the listed parts. 
     Referring now to  FIG. 1 , an example of a tissue collection assembly  100  of this disclosure is shown in an assembled view. The assembly  100  generally comprises a surgical resection system  102  used to cut or resect bodily tissue from a donor site. Alternatively, other cutting instruments, such as a burr (not shown), may be used. The resection system  102  is in fluid communication with a filter assembly  120  for isolating the tissue fragments which have been aspirated through the resection system  102 . Notably, while this disclosure relates primarily to cartilage repair, the tissue collection assembly  100  of this disclosure can be used for harvesting various autologous tissue types (e.g., cartilage, bone, fat, meniscus, tendon, ligament, etc.) in a range of surgical or cosmetic applications. 
     Still referring to  FIG. 1 , the resection system  102  includes a surgical blade  103  comprising a cannulated shaft  104 , and a handpiece  122  coupled to the shaft  104  via a hub  124 . The shaft  104  has a proximal end  104   a  coupled to the hub  124  and a distal end defining a cutting end  104   b.  The handpiece  122  provides a pathway for fluid and tissue fragments to flow from the cutting end  104   b  of the shaft  104  to the filter assembly  120 . In examples, the handpiece  122  is a motorized drive unit including a suction lever  106  to control the flow of the tissue fragments through the handpiece  122 . In examples, the handpiece  122  includes a rigid tube  131  with a barb  132  in fluid communication with the filter assembly  120 . 
     The filter assembly  120  comprises a substantially cylindrical housing  134  with an outlet  138  removeably attached to the housing  134  for connecting the housing  134  to a vacuum source (not shown). In examples, the vacuum source is a vacuum pump or other suitable apparatus for providing aspiration during the surgical procedure. An inlet  136  is formed integrally with a compressor  142  which at least partially extends through a port  135  in the housing  134 . The inlet  136  is configured to be removeably coupled to the barb  132 . In examples, the inlet  136  and the barb  132  are connected by flexible tubing (not shown). The inlet  136  and the body of the compressor  142  are configured to axially slide within the internal volume  133  of the housing toward the outlet  138 . Thus, a diameter of the port  135  is selected to accommodate the passing of both of the inlet  136  and the compressor  142  through at least a portion of the housing  134 . 
     The cutting end  104   b  of the shaft  104  is shown in greater detail in  FIGS. 2A and 2B . As illustrated in  FIG. 2A , the cutting end  104   b  of the shaft  104  includes a cutting edge  116  for fragmenting soft tissue or bone. The shaft  104  furthermore defines an aspiration lumen  126  ( FIG. 2B ) communicating with the cutting edge  116  to remove the fragmented tissue and fluid from the surgical site. In examples, the cutting end  104   b  of the shaft  104  includes an external shield  118  removeably disposed around the shaft  104  adjacent to the cutting edge  116 . The shield  118  is configured to minimize the amount of foreign material being sucked into the lumen  126 . Preferably, the shield  118  is an elastomeric shield that minimizes ingestion of material which is not directly in front of the lumen  126 . Advantageously, the pliable nature of the shield  118  minimizes interference with the mobility of the shaft  104  during use. 
     Turning now to  FIG. 3A , an exemplary handpiece  122  of this disclosure is illustrated in a cross-sectional view. In  FIG. 3A , it can be seen that the hub  124  of the resection system  102  is coupled to the shaft  104  via an opening  128  formed in the hub  124 . The handpiece  122  may also include various internal shielding structures to mitigate contamination of the tissue fragments as they travel along a passageway  121  extending through the handpiece  122 . For example, the handpiece  122  may include a flow diverter  130  ( FIG. 3B ) which causes the tissue fragments to bypass the most commonly contaminated areas A of the handpiece  122 . In an alternative example, illustrated in  FIG. 3C , a sterile sleeve  123  may be integrated within the passageway  121  to prevent contamination of the tissue fragments by the handpiece  122 . In examples, the sterile sleeve  123  is made of a thermally-conductive material which is also selected to be deformable, collapse-resistant and shear-resistant through the rigid tubing  131  and the barb  132 . 
     Alternative examples of the handpiece  122  are shown with regard to  FIGS. 3D and 3E . In the example shown in  FIG. 3D , the tissue fragments could be diverted to flow outside of the blade  203 . For example, an outflow port  225  could be integrated on the hub  224  of the blade  203  and connected with tubing  227  ( FIG. 3E ) which is attached to the filter assembly  120 . An integral valve  229  ( FIG. 3D ) or separate valve  229 ′ attached to the suction lever  206  of the handpiece  222  ( FIG. 3E ) could be used to control suction. Additionally, a small portion of aspirated fluid could be diverted from the hub  224  to cool down the handpiece  222 . In another example, illustrated in  FIG. 3F , to fully cool down the handpiece  322 , aspirated fluid flowing through the outflow port  325  on the hub  324  could be fed through a filter (not shown) and then back into the hub  324 , and then finally through the handpiece  322 . In yet another example, shown in  FIG. 3G , the suction lever  406  of the handpiece  422  may utilize ambient air  431  to control the suction of the blade  402  when two suction ports or inlets  436 ,  437  are present. The suction lever  406  on the handpiece  422  controls the air  431  running backwards into the hub  424 , thus reducing the effective suction strength of the blade  402 . 
     Turning now to  FIG. 4A , an example of the filter assembly  120  of this disclosure is illustrated in more detail. A filter  140  is disposed within the internal volume  133  of the housing  134  for the collection of tissue fragments about an outer surface of the filter  140 . In examples, the filter  140  is a hollow, tubular filter allowing suction to be applied through the interior of the filter  140 . However, other suitable filters having any number of possible geometric shapes may be employed. As suction is applied, fluid flows through holes  141  in communication with the interior of the filter  140 , causing the tissue fragments to be collected about the outer surface of the filter  140 . In examples, a size of the holes  141  is selected to be smaller than a pre-selected size of the tissue fragments. 
     As shown in  FIG. 4B , the filter  140  is coupled to the outlet  138  such that the filter  140  and the outlet  138  are removeable from the housing  134  simultaneously. As stated above, the compressor  142  is extendable through a port  135  in the housing and configured to axially slide at least partially within the housing  134  toward the outlet  138 . In examples, the compressor  142  may slide within the housing  134  by a manual force exerted on a surface of the compressor  142 . Alternatively, closing off the inlet  136  while suction is applied to the filter assembly  120  may act as a force on the surface of the compressor  142 , causing the compressor  142  to advance toward to the outlet  138 . As the compressor  142  is moved toward the outlet  138 , tissue fragments F collected within the housing  134  are compacted against outlet  138 , thus allowing measurement of the volume of tissue fragments F harvested. To facilitate this, a portion of the housing  134  may be provided with a transparent surface  144  to allow direct visualization of the tissue fragments F. Furthermore, the transparent surface  144  may include markings  148  ( FIG. 5B ) to aid in the measurement of the volume of the tissue fragments F. If more tissue fragments are required, additional aspiration could be applied. Notably, during aspiration of the tissue fragments F, a gap must be maintained between the compressor  142  and the filter  140  so that the compressor  140  does not block the collection of the tissue fragments about the filter  140 . In examples, a biasing member, such as a spring  143  ( FIG. 7A ) may be provided to return the compressor  140  back to its initial position away from the filter  140  when the measurement of the tissue fragments F is complete. 
     Turning now to  FIG. 5A , examples of the housing  134  of this disclosure may include a shearing lip  150  at the proximal end of the housing  134  and slidably disposed about a portion of the filter  140 . A first portion  150   a  of the lip  150  is fixedly disposed within the housing  134  and a second portion  150   b  of the lip  150  is removeably disposed within a cavity  151  of the outlet  138 . Thus, the outlet  138  and the filter  140  may be removed from the housing  134  without changing the position of the lip  150  relative to the housing  134 . As the outlet  138  and the filter  140  are removed from the housing  134  ( FIG. 5B ), the lip  150  acts to shear the tissue fragments off of the outer surface of the filter  140 , thus leaving the tissue fragments within the filter assembly  120  and ready for delivery to a repair site. After removal of the filter  140  ( FIG. 5C ), a biocompatible agent may be introduced into the housing  134  to facilitate the attachment of the fragments to the repair site after delivery. The agent may comprise any suitable biological or synthetic agent. For example, the agent may comprise hyaluronic acid, alginate, cross-linked alginate, collagen, fibrin glue, fibrin clot, poly(N-isopropulacrylamide), agarose, chitin, chitosan, cellulose, polysaccharides, poly(oxyalkylene), a copolymer of poly(ethylene oxide)-poly(propylene oxide), poly(vinyl alcohol), polyacrylate, Matrigel, or mixtures thereof. 
     As shown in  FIG. 6A , examples of the compressor  142  of this disclosure may further include one or more asymmetrical wires  152  attached to the compressor  142 . For example, the wires  152  may be slidably received within grooves  154  on an outer surface of the compressor  142 . The wires  152  may be used for mixing the collected tissue fragments with the introduced agent. Rotary motion is transferred to the wires  152  by rotation of the compressor  142  relative to the housing  134  to create a mixture of agent and tissue fragments within the housing  134  ( FIG. 6B ). Notably, the wires  152  may be made of a deformable material such that the wires  152  do not impede axial movement of the compressor  142  through the housing  134  ( FIG. 6C ). 
     Turning now to  FIG. 7A , an example of a delivery device  156  used to deliver the tissue fragments collected in the filter assembly  120  is shown. The delivery device  156  generally comprises a cannulated shaft  155  and a handle  157 . The handle  157  is configured to mate with a coupling portion  174  of the housing  134  (for example, a Luer or threaded fitting) of the filter assembly  120 , as shown in  FIG. 7B . A channel  160  extending through the shaft  155  and the handle  157  of the delivery device  156  is configured for the passage of a plunger  158  inserted through the inlet  136  of the compressor  142  to deliver the tissue fragments out of a delivery end  161  of the shaft  155 . In examples, a diameter of the channel  160  is selected to minimize resistance of the tissue fragments as the plunger  158  is advanced through the channel  160 . A lip  196  surrounds at least a portion of the circumference of the delivery end  161  of the shaft  155  and extends a distance radially from the shaft  155 . A surface of the lip  196  is aligned with a portion of an opening  194  of the shaft  155 , the surface being substantially planar. This configuration allows the lip  196  to be dragged over the repair site during tissue delivery while still leaving a smooth surface on the repair site. Advantageously, use of the delivery device  156  allows delivery of the tissue fragments to a repair site without direct human contact with the fragments. However, in an alternative example of the delivery device  556 , shown in  FIG. 7C , the handle  557  of the delivery device  556  may be provided with an access door  559  allowing direct access to the tissue fragments, if desired. 
     As shown in  FIG. 8A , a manual actuator  162 , such as a thumb roller, may be provided on a surface of the handle  157  of the delivery device  156  for one-handed delivery of the tissue fragments to the repair site. In examples, as the actuator  162  is rotated, gear teeth  166  of an integral pinion gear  164  engage with corresponding teeth  168  on a surface of the plunger  158 , causing the plunger  158  to move axially within the channel  160 . In alternative examples, not shown, the interface between the actuator  162  and the plunger  158  could be a frictional engagement. In further examples, shown in  FIG. 8B , limiting the loss of tissue fragments around the actuator  162  can be accomplished by preventing the rotation of the actuator  162  until mated with the plunger  158 , and/or smoothing the gear teeth  166  in one area B, while still allowing full rotation of the actuator  162  ( FIG. 8B ). 
     Turning now to  FIG. 9A , when inserted through the compressor  142 , the plunger  158  and the compressor  142  advance together through the housing  134  to push the tissue fragments into the channel  160  of the delivery device  156 . The lip  150  now acts as a funnel to facilitate the flow of the tissue fragments into the channel  160 . As the plunger  158  and the compressor  142  are advanced together, the compressor  142  is prevented from further advancement by the first portion  150   a  of the lip  150  ( FIG. 9B ). Once the compressor  142  is stopped by the lip  150 , a mechanism allows the plunger  158  to advance through the second portion  150   b  of the lip  150  and into the channel  160  of the delivery device  156  ( FIG. 9C ). One example of the mechanism is described below with regard to  FIGS. 11A-C . However, other suitable mechanisms for controlling this relative motion between the compressor  142  and the plunger  158  through the housing  134  are contemplated by this disclosure. 
     Alternative examples of the plunger  658  of this disclosure can incorporate mixing wires  652  within the plunger  658 , as shown in  FIGS. 10A and 10B . For example, the plunger  658  may be configured for the passage of a deformable mixing wire  652 . The wire  652  is configured to be rotated and/or advanced within the delivery device  656  to further mix the contents of the delivery device  656  before delivery to the repair site. 
     Further details regarding the interface between the compressor  142  and the plunger  158  are shown in  FIGS. 11A-C . In order for the compressor  142  and the plunger  158  to move together through the housing  134 , a mechanism is required to join them temporarily. In examples, the mechanism is a cam lever  170  extending from an interior of the plunger  158  through a slot  172  in the outer surface of the plunger  158 . As shown in  FIG. 11A , the cam lever  170  initially pushes against the inlet  136  at both points “a” and “b”. As the inlet  136  and the plunger  158  are advanced through the housing  134 , the cam lever  170  eventually comes into contact with a stationary feature (i.e., the distal end of the housing  134 ) and, with further advancement, begins to pivot, first lifting off of point “a” and then disengaging with point “b” ( FIG. 11B ). As the plunger  158  continues to advance, the cam lever  170  rotates to a horizontal position within the plunger  158 , allowing the plunger  158  to continue advancing while leaving the compressor  142  in place ( FIG. 11C ). In alternative examples (not shown), a rotary motion of the plunger  158  relative to the compressor  142  could lock and unlock the plunger  158  and the compressor  142 . 
     Turning now to  FIG. 12A , in operation, the resection system  102  of the tissue collection assembly  100  is brought into contact with a donor site and the operator cuts a desired amount of donor tissue from the site using the cutting end  104   b.  The vacuum source (not shown) aspirates fluid and the cut tissue through the shaft  104  and the handpiece  122  to the filter assembly  120 . During aspiration, the fluid and cut tissue pass over the filter  140  ( FIG. 4A ) within the housing  134  where tissue fragments are isolated and/or retained on the outer surface of the filter  140 . In examples, following aspiration of the fluid and cut tissue, the inlet  136  of the compressor  142  may be closed off using, for example, a valve, stop, plug, or other suitable device. The compressor  142  may then be advanced within the housing  134  to compress the tissue fragments within the housing  134  for measurement of the volume of the fragments. Aspiration of the fluid and cut tissue may be repeated until a desired volume of tissue fragments is reached, at which point the filter assembly  120  is removed from the resection system  102 . The outlet  138  and the filter  140  are then removed from the housing  134 , causing the lip  150  ( FIG. 5A ) to shear the tissue fragments from the outer surface of the filter  140 . Optionally, a syringe or other instrument (not shown) containing a biocompatible agent is coupled to the housing  134 , for example, by a Luer lock or other suitable connection in the housing  134 . The agent is then injected into the housing  134  to mix with the tissue fragments. In examples, deformable wires  152  attached to the compressor  142  ( FIG. 6A ) may be rotated via rotation of the compressor  142  relative to the housing  134  to mix the tissue fragments and the agent to promote even distribution of the tissue fragments within the agent. 
     As shown in  FIG. 12B , once the desired mixture is collected within the housing  134 , the operator inserts the plunger  158  of the delivery device  156  into the inlet  136  of the compressor  142  and advances the plunger  158  and the compressor  142  together until the compressor  142  is prevented from further advancement within the housing  134 . The compressor  142  may be latched into this position as the plunger  158  continues to travel past the region of the actuator  162 . The operator then manually actuates the actuator  162  on the handle  157  to advance the plunger  158  through the delivery device  156  for controlled application of the tissue and agent mixture to the repair site. Alternatively, the mixture can be placed onto a tissue scaffold or used for further processing. 
     An alternative example of the filter assembly  720  is shown in  FIG. 13 . In the example of  FIG. 13 , suction is applied to the housing  734  through an offset outlet  738  providing fluid flow about the outer surface of the filter  740 . As the suction is applied, fluid flowing through holes  741  in communication with the interior of the filter  740  causes the tissue fragments to be collected about the inner surface of the filter  740 . In examples, a size of the holes  741  is selected to be smaller than a pre-selected size of the tissue fragments. The filter  740  of  FIG. 13  may furthermore be configured for the passage of a syringe-type plunger  758  through an interior of the filter  740  to deliver the tissue fragments to the repair site. 
     In other examples, the filter  840  may be removeably disposed within the hub  824  of the blade  803 , as shown in  FIGS. 14A and 14B . In  FIG. 14A , as suction S is applied, the filter  840  collects tissue fragments F on an exterior surface of the filter  840 . In  FIG. 14B , as suction S is applied, the filter  840  collects tissue fragments F on an interior surface of the filter  840 . Optional joints  890  extend between the filter  840  and the cutting end  804   b  of the blade  803  for facilitating removal of the filter  840  from the blade  803 . 
       FIGS. 15A-C  illustrate another example of a mixing wire  952  incorporated into the plunger  958 .  FIG. 15A  shows the wire  952  housed within a track  988  of the plunger  958  as the plunger  958  is inserted through the compressor  942  within the housing  934  of the filter assembly  920 . In  FIG. 15A , the wire  952  is exposed beyond the distal end of the plunger  958  and can be used to mix the tissue fragments F with the biocompatible agent. As the plunger  958  advances through the compressor  942 , the plunger  958  pushes the compressor  942  and the wire  952  together through the housing  934 . As shown in  FIG. 15B , when the plunger  958  is moved distally along the full length of the housing  934 , the compressor  942  engages a latch  984  in the housing  934 , preventing the compressor  942  from moving proximally. In addition, a bent portion  986  of wire  952  interferes with the compressor  942 . As the plunger  958  continues to move distally, the plunger  958  covers the wire  952  until the wire  952  bottoms out at the end of the track  988  on the surface  982  of the plunger  958 . At this stage, the distal end of the plunger  958  and wire  952  are substantially flush. The plunger  958  and the wire  952  continue to advance together within the housing  934  while the compressor  942  stays locked within the housing  934  ( FIG. 15C ). 
     The assemblies and devices described herein may be considered disposable, although they may also be reused upon sterilization, such as by gamma irradiation, ethylene oxide, formalin, hydrogen peroxide, or sodium hypochlorite. The filters and syringes discussed herein may be commercially obtained. In examples, the assemblies and devices, and their respective component parts, may be made of plastic, metal, or other suitable materials. 
     While the disclosure has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present application as defined by the appended claims. Such variations are intended to be covered by the scope of this present application. As such, the foregoing description of examples of the present application is not intended to be limiting, the full scope rather being conveyed by the appended claims.