Patent Publication Number: US-2022211396-A1

Title: Geared instrument for minimally invasive surgery

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Patent Application Ser. No. 62/854,073, filed May 29, 2019, the entirety of which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     This disclosure generally relates to systems and methods for orthopedic surgery. More particularly, this disclosure relates to systems and methods for performing minimally invasive repair of the foot. 
     BACKGROUND 
     Fusion of the metatarsal-phalangeal (MTP) joint can be used to relieve pain in the forefoot. This procedure can also be used to correct deformities in the foot. The deformities can be caused by injury, arthritis, or genetic defects. 
     In some procedures, prior to fusing, the cartilage within the joint must be removed. This may be done using cup- or cone-shaped reamers. This typically requires the use of an “open” procedure involving fully dislocating the joint in order to approach each side of the joint. These procedures also typically require the use of multiple reamers and several steps to complete the process. Minimally invasive processes have been developed, but typically require the use of burrs. Such burrs remove bone in addition to the cartilage, thereby shortening the bone. This can lead to additional complications. Moreover, use of burrs commonly necessitates a freehand technique in which the surgeon must remove the cartilage with little to no guidance. As such, there is a risk of incomplete joint debridement or the creation of irregular surfaces at each end of the bones to be fused, which could make fusion more difficult. 
     SUMMARY 
     In one aspect, a system is disclosed that includes an instrument and a distractor. The instrument includes a shaft extending from a first end to a second end and defining a first axis between the first end and the second end. The instrument further includes a first gear coupled to the first end of the shaft such that rotation of the shaft about the first axis causes rotation of the first gear about the first axis. The instrument further includes a second gear enmeshed with the first gear. The instrument further includes a reamer coupled to the second gear. Rotation of the shaft about the first axis causes rotation of the reamer about a second axis that is non-parallel with the first axis such that, with the instrument at least partially disposed in a joint space between a first bone and a second bone, rotation of the reamer removes material from the joint space. The distractor includes a first arm defining a first passage configured to receive a first pin inserted in the first bone and a second arm defining a second passage configured to receive a second pin inserted in the second bone. The distractor further includes a retainer extending from the first arm, wherein the retainer is configured to engage the instrument to retain the instrument in position. The distance between the first passage and the second passage is adjustable. 
     In another aspect, a method includes forming an incision to access a metatarsophalangeal joint. The method further includes locating an instrument partially within the metatarsophalangeal joint. The instrument includes a shaft extending from a first end to a second end and defining a first axis between the first end and the second end. The instrument further includes a first gear coupled to the first end of the shaft such that rotation of the shaft about the first axis causes rotation of the first gear about the first axis. The instrument further includes a second gear enmeshed with the first gear. The instrument further includes a reamer coupled to the second gear. Rotation of the shaft about the first axis causes rotation of the reamer about a second axis that is non-parallel with the first axis. The method further includes rotating the shaft about the first axis to rotate the reamer about the second axis to remove material from the metatarsophalangeal joint. 
     In another aspect, an instrument includes a shaft, a first gear, a second gear, and a reamer. The shaft extends from a first end to a second end and defines a first axis between the first end and the second end. The first gear is coupled to the first end of the shaft such that rotation of the shaft about the first axis causes rotation of the first gear about the first axis. The second gear is enmeshed with the first gear. The reamer is coupled to the second gear. Rotation of the shaft about the first axis causes rotation of the reamer about a second axis that is non-parallel with the first axis such that, with the instrument at least partially disposed in a joint space between a first bone and a second bone, rotation of the reamer removes material from the joint space. The reamer is one of a cup reamer and a cone reamer. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The features and advantages of the present invention will be more fully disclosed in, or rendered obvious by the following detailed description of the preferred embodiments, which are to be considered together with the accompanying drawings wherein like numbers refer to like parts. 
         FIG. 1  shows a perspective view of a geared instrument, according to one embodiment described herein. 
         FIG. 2  shows a perspective view of the geared instrument of  FIG. 1 , in which the housing is transparent to show the shaft disposed therein. 
         FIG. 3  shows a detail view of the first end of the geared instrument of  FIG. 1 . 
         FIG. 4  shows a step of a method of performing a surgical procedure on an MTP joint in which a first pin is inserted in the metatarsal and a second pin is inserted in the proximal phalanx. 
         FIG. 5  shows a step of a method of performing a surgical procedure on an MTP joint in which a distractor is coupled to the pins. 
         FIG. 6  shows a step of a method of performing a surgical procedure on an MTP joint in which the metatarsal and proximal phalanx are separated. 
         FIG. 7  shows a step of a method of performing a surgical procedure on an MTP joint in which the geared instrument is inserted in the MTP joint. 
         FIG. 8  is a flowchart illustrating a method of performing a surgical procedure on an MTP joint. 
         FIG. 9  is a side view of a geared instrument, according to another embodiment described herein, in which the housing is transparent to show the shaft disposed therein. 
         FIG. 10  is a detail perspective view of the geared instrument of  FIG. 9 . 
         FIG. 11  is a perspective view of the geared instrument of  FIG. 9  in use. 
     
    
    
     DETAILED DESCRIPTION 
     The description of the exemplary embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description. In the description, relative terms such as “lower,” “upper,” “horizontal,” “vertical,” “proximal,” “distal,” “above,” “below,” “up,” “down,” “top” and “bottom,” as well as derivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description and do not require that the apparatus be constructed or operated in a particular orientation. Terms concerning attachments, coupling and the like, such as “connected” and “interconnected,” refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. 
     The present disclosure describes a geared instrument for use in preparing a joint for fusion, distractors to be used in conjunction with such a geared instrument, and methods of using the same. The instruments and methods are particularly well-suited for preparation of the MTP joint, however, it should be understood that such instruments and methods can be used for preparing other joints for fusion. The geared instrument includes a shaft configured to rotate about a first axis and has a first gear at a first end of the shaft. The first gear is coupled to a second gear that rotates with a reamer configured to be used to prepare a metatarsal or proximal phalanx for a fusion procedure. The reamer rotates about a second axis that is non-parallel with the first axis. 
       FIGS. 1 and 2  illustrate one embodiment of a geared instrument  2  for use in performing a surgical procedure, for example, for preparing an MTP joint for fusion. The geared instrument  2  comprises a shaft  4 . In some embodiments, one end of the shaft  4  may be configured for coupling to a mechanical drive. For example, the shaft  4  may be configured to couple to a mechanical drive via a threaded connection, a press-fit connection, and/or any other suitable connection. For example, in one embodiment, the shaft  4  may be configured to engage with a collet. The mechanical drive may be, for example, a surgical drill. In other embodiments, the shaft  4  may include a handle that allows the shaft to be rotated by hand. The shaft  4  is rotatable about the longitudinal axis  6  of the shaft  4 . 
     As shown best in  FIG. 3 , a first gear  8  is located at, and coupled to, the distal end of the shaft  4 . As will be described further herein, the first gear  8  may be, for example, a bevel gear, a worm gear, a spiral bevel gear, a hypoid gear, and/or a crown gear. The first gear  8  may be integrally formed with the shaft  4 . For example, the shaft  4  and first gear  8  may be formed by injection molding, casting, be machined out of a single piece of material, or be formed by other processes. Alternatively, the first gear  8  may be a separate component that is joined to the shaft  4  by any appropriate method (e.g., welding, bonding, press-fit, fasteners, etc.). 
     Returning to  FIGS. 1 and 2 , the shaft  4  may be disposed within a housing  10 .  FIG. 2  shows the housing  10  in transparent form to allow the shaft  4  to be viewed inside the housing  10 . In one embodiment, as shown, the housing  10  is a tubular housing extending from a first end  12  to a second end  14 . An opening (not shown) at the second end  14  of the housing  10  allows for the passage of the shaft  4  through the opening and out of the housing  10  such that the end of the shaft  4  can be rotated by hand or via a mechanical drive, as described above. In some embodiments, a portion of the shaft  4  may be captured in the housing  10  to prevent the shaft  4  from being inadvertently removed from the housing  10 . In other embodiments, the shaft  4  is removable from the housing  10 . The geared instrument  2  may include a cap  11  coupled to the housing  10 . During assembly of the geared instrument  2 , the shaft  4  may be inserted into the housing  10 . The cap  11  may then be coupled to the housing  10  to retain the shaft  4  in place. The shaft  4  may have a shoulder or flange that contacts the cap  11  to prevent removal of the shaft  4  from the housing  10 . 
     As shown in  FIG. 3 , a second gear  16  is located within the housing  10  at the first end  12  of the housing  10 . The second gear  16  is configured to mesh with the first gear  8  (i.e., the teeth of the gears  8 ,  16  mesh together to translate rotation of the first gear  8  to rotation of the second gear  16 ). The second gear  16  may comprise any suitable gear such as, for example, a bevel gear, a worm gear, a spiral bevel gear, a hypoid gear, and/or a crown gear. A reamer  18  is coupled to the second gear  16  such that the reamer  18  rotates with the second gear  16 . In some embodiments, second gear  16  and reamer  18  are integrally formed. For example, second gear  16  and reamer  18  may be formed by injection molding, casting, be machined out of a single piece of material, or be formed by other processes. Alternatively, the second gear  16  may be a separate component that is joined to the reamer  18  by any appropriate method (e.g., welding, bonding, press-fit, fasteners, etc.). In some embodiments, a shaft may extend between the second gear  16  and the reamer  18  and extend through an aperture in the housing  10 . 
     In some embodiments, the reamer  18  rotates at the same rotational speed as the second gear  16  (e.g., the first gear  8  and the second gear  16  may have a 1:1 gear ratio). In other embodiments, the reamer  18  rotates at a different rotational speed than the second gear  16 . For example, additional gearing between the reamer  18  and the second gear  16  may provide for different rotational speeds. Alternatively, or additionally, the gear ratio of the first gear  8  and the second gear  16  may have a gear ratio other than 1:1. The second gear  16  and the reamer  18  are rotatable about a second axis  20 . The second axis  20  is non-parallel with the first axis  6 . For example, in some embodiments, the first axis  6  and the second axis  20  are orthogonal. In other embodiments, the first axis  6  and the second axis  20  are disposed at an oblique angle. 
     The reamer  18  can include any appropriate geometry. For example, the reamer  18  may be in the form of a cup or cone reamer and be used to prepare the metatarsal and/or proximal phalanx for MTP fusion, midfoot fusion, a Lapidus procedure, or any other desired procedure. For example, a cone reamer may be used to prepare the metatarsal and a cup reamer may be used to prepare the proximal phalanx. Such cup and cone reamers are described in, for example, U.S. Pat. No. 9,848,893, issued on Dec. 26, 2017, entitled BONE IMPLANTS AND CUTTING APPARATUSES AND METHODS, which is incorporated herein by reference in its entirety. 
     In other embodiments, the reamer  18  is shaped and configured to form a cavity in a bone (e.g., metatarsal or proximal phalanx) such that the cavity can receive an implant. For example, the reamer can be shaped to form a cavity to receive a cartilage-like polymer implant such as the CARTIVA synthetic cartilage implant sold by Wright Medical Group N.V. 
     In some embodiments, shown in  FIGS. 9-11 , the geared instrument  2  includes two reamers  18   a ,  18   b  positioned on opposite sides of the shaft  4  and facing away from one another. For example, the first reamer  18   a  may be in the shape of a cup reamer and extend in a first direction (e.g., for preparing the end of a proximal phalanx). The second reamer  18   b  may be in the shape of a cone reamer and extend in a second direction (e.g., for preparing the end of a metatarsal). Each reamer  18   a ,  18   b  may be coupled to a gear  16   a ,  16   b  that meshes with first gear  8 . In this way, the metatarsal and proximal phalanx may be prepared simultaneously, as illustrated in  FIG. 11 . The first  18   a  and second  18   b  reamers may, in some embodiments, rotate at the same rotational rate. In other embodiments, the first  18   a  and second  18   b  reamers rotate at different rotational rates. For example, the gear ratio of first gear  8  to gear  16   a  may be different than the gear ratio of the first gear  8  to the gear  16   b . In some embodiments the gears  16   a ,  16   b  rotate in the same direction (e.g. clockwise); in other embodiments, the gears rotate in opposite directions (i.e. clockwise and counterclockwise). 
     In some embodiments, the housing  10  allows the reamer  18  and/or the second gear  16  to be removed from the housing  10 . In other embodiments, the reamer  18  and/or the second gear  16  are not intended to be removed from the housing  10 . 
     When the shaft  4  is in place in the housing  10 , the first gear  8  meshes with the second gear  16 . The coupling of the first gear  8  and the second gear  16  translates rotation of the shaft  4  about the first axis  6  to rotation of the reamer  18  about the second axis  20 . In some embodiments, the shaft  4  and the reamer  18  rotate at the same rotational speed. In other embodiments, the shaft  4  and the reamer  18  rotate at different rotational speeds (e.g., first gear  8  and second gear  16  have a gear ratio other than one). The shaft  4  may be rotated about the first axis  6  by, for example, a clinician gripping the shaft  4  or using a mechanical drive. The shaft  4  may be rotatable in a first direction and/or a second direction (i.e., clockwise or counterclockwise). Rotation of the reamer  18  allows one or more surgical procedures to be performed without needing direct axial access to a bone. For example, the reamer  18  may be used to prepare an MTP joint for a fusion surgery. Additionally, or alternatively, reamer  18  may be used to form a cavity in a bone to receive an implant. 
     The geared instrument  2  is configured to facilitate one or more surgical procedures. For example, in some embodiments, the geared instrument  2  is sized and configured to facilitate a fusion of the MTP joint. The geared instrument  2 , and specifically the housing  10 , is configured to fit through an incision formed adjacent to the MTP joint. For example, as described further herein, the housing may be inserted through a superior incision formed above the MTP joint. The use of the geared instrument  2  may eliminate the need for complete dislocation of the joint. Instead, the housing  10  fits within the MTP joint through the incision and allows cartilage within the joint to be removed and otherwise assist with preparation of the joint for fusion. 
     For example, in one embodiment, the geared instrument  2  is sized and configured for insertion of the housing  10  between the first metatarsal  200  and proximal phalanx  202  (as shown in  FIG. 7 ). The shaft  4  is rotated about the first axis  6 , rotating the reamer  18  about the second axis  20  to prepare the metatarsal  200  or proximal phalanx  202  for fusion (e.g., removing cartilage). Optionally, after preparing the metatarsal  200  or the proximal phalanx  202 , the geared instrument  2  is removed from the joint, turned, and reinserted through the incision such that it can be used to prepare the other surface of the metatarsal-phalangeal joint (e.g., by removing cartilage). Once the geared instrument  2  is reinserted into the MTP joint, the shaft  4  is rotated to prepare the respective bone. In other embodiments, geared instrument  2  includes two reamers extending in opposite directions, each coupled to shaft  4  via first gear  8  such that both bones can be prepared simultaneously, as described above with reference to  FIGS. 9-11 . 
       FIGS. 4-7  illustrate a method of performing a surgical procedure on an MTP joint. Although these figures illustrate a method of preparing the first MTP joint, the apparatuses and methods described herein may be used to prepare any MTP joint for fusion. In  FIGS. 4-7 , only the bony anatomy of the foot is shown for clarity. As shown in  FIG. 4 , a first pin  22  is inserted into the first metatarsal  200  and a second pin  24  is inserted into the proximal phalanx  202 . In some embodiments, incisions are made in the skin prior to insertion of the pins  22 ,  24 . The pins  22 ,  24  may be, for example, Steinmann pins, olive wires, K-wires (Kirschner wires), or any other pin or wire capable of being fixed in the metatarsal  200  or proximal phalanx  202 . 
     As shown in  FIG. 5 , a distractor  26  is then engaged with the pins  22 ,  24 . In some embodiments, the distractor  26  has a first arm  28  configured to engage the first pin  22  and a second arm  30  configured to engage the second pin  24 . The first arm  28  and the second arm  30  are spaced apart along a longitudinal member  34 . The first and second arms  28 ,  30  may define passages  28   a ,  30   a , respectively, to receive a respective pin  22 ,  24 . For example, the first arm  28  may include a cylindrical sleeve  31  extending downward (i.e., transverse to the longitudinal member  34 ) and defining the passage  28   a  to receive the first pin  22  and the second arm  30  may include a cylindrical sleeve  33  extending downward (i.e., transverse to the longitudinal member  34 ) and defining the second passage  30   a  to receive the second pin  24 . The first and second arms  28 ,  30  may also include means for fixing the arms  28 ,  30  to the respective pin  22 ,  24  (e.g., a collet, threads, etc.). The first arm  28  and the second arm  30  are translatable with respect to one another such that the distractor  26  can be used to increase and/or decrease the distance between the pins  22 ,  24  and, thereby, increase and/or decrease the distance between the metatarsal  200  and proximal phalanx  202 . 
     For example, as shown in  FIG. 5 , the first arm may extend from a mounting block  32  that is translatable along the longitudinal member  34 . The second arm  30  extends from a first end of the longitudinal member  34  and may be fixed in position relative to the longitudinal member  34 . For example, the second arm  30  may be integrally formed with the longitudinal member  34 . In some embodiments, the longitudinal member  34  includes ratchet teeth and the mounting block  32  is coupled to a pawl  36 . The pawl  36  is configured to engage the ratchet teeth to control movement of the mounting block  32  along the longitudinal member. The mounting block  32  may also be coupled to an adjustment knob  38  that allows the user to control movement of the mounting block  32  along the longitudinal member  34  to adjust the distance between the first arm  28  and the second arm  30  and, thereby, the distance between the first pin  22  and the second pin  24 . Similar distractors that can be adapted to be used with the geared instrument  2  are described in U.S. Pat. No. 9,770,272, issued Sep. 26, 2017, entitled ORTHOPEDIC COMPRESSION/DISTRACTION DEVICE, and PCT patent application publication no. WO 2015/137976, published Sep. 17, 2015, entitled ORTHOPEDIC COMPRESSION/DISTRACTION DEVICE, both of which are incorporated herein by reference in their entireties. 
     Although the movable arm (first arm  28 ) is shown in engagement with the pin that is inserted in the metatarsal  200 , it should be understood that other orientations of the distractor  26  can be used. For example, the movable arm (first arm  28 ) may be engaged with the pin that is inserted in the proximal phalanx  202 . Further, in some embodiments, both arms  28 ,  30  may be translatable along the longitudinal member  34 . 
     As shown in  FIG. 6 , the distance between the metatarsal  200  and the proximal phalanx  202  can be increased using the distractor  26 . For example, a surgeon can increase this distance by translating the mounting block  32  along the longitudinal member  34  (e.g., by rotating the knob  38 ). With the first arm  28  in the desired position, the pawl  36  engages one or more ratchet teeth on the longitudinal member  34  to restrict movement of the first arm  28  along the longitudinal member  34 . Optionally, the distractor  26  may include a means for locking the arms  28 ,  30  in the desired position to prevent inadvertent movement of the arms  28 ,  30  (e.g., a set screw). 
       FIG. 7  shows the geared instrument  2  inserted into the space between the metatarsal  200  and the proximal phalanx  202 . As shown, in some embodiments, the distractor  26  includes a retainer  40  for holding the geared instrument  2  in position. For example, the retainer  40  may extend from first arm  28  (e.g., parallel to the longitudinal member  34 ) and define a cavity within which housing  10  of geared instrument  2  is retained. In some embodiments, retainer  40  may include fingers defining the cavity and configured to engage the housing  10  to hold it in position. For example, the fingers may flex during insertion of the housing  10  such that the fingers grasp the housing  10  to retain the geared instrument  2 . In some embodiments, when the geared instrument  2  is coupled to the retainer  40 , the distance from the center of the first pin  22  to the longitudinal axis  6  is between about 10 mm and about 20 mm. In other embodiments (not shown), the retainer  40  extends from the second arm  30 . In such embodiments, the distance from the center of the second pin  24  to the longitudinal axis  6  may be between about 10 mm and about 20 mm. 
     Once the geared instrument  2  is positioned in the MTP joint, the reamer  18  may be used to perform a surgical procedure (e.g., remove cartilage from the joint). As the shaft  4  is rotated, the reamer  18  rotates and removes material (e.g., cartilage or bone) from the joint space. As the reamer rotates, the arms  28 ,  30  may be moved closer to one another to decrease the space between the metatarsal  200  and the proximal phalanx  202 , thereby allowing the reamer  18  to continue to remove material. Optionally, after preparing one side of the MTP joint, the geared instrument  2  may be removed from the joint and rotated to prepare the other of the metatarsal  200  and phalanx  202 , as described above. 
     Alternatively, as described above, in some embodiments, the geared instrument  2  includes two reamers  18   a ,  18   b  extending in opposite directions such that both bones can be prepared simultaneously.  FIG. 11  shows such an embodiment in use. As can be seen in  FIG. 11 , the geared instrument may be positioned such that the cone reamer  18   b  is oriented toward the first metatarsal  200  and the cup reamer  18   a  is oriented toward the proximal phalanx  202 . In such embodiments, rotation of the shaft  4  is translated to rotation of both the cup reamer  18   a  and the cone reamer  18   b . As a result, material may be removed from both bones simultaneously. This may reduce the total amount of time needed to perform the procedure. 
     In some embodiments, an irrigation clip is attached to the distractor  26  or otherwise directed at the MTP joint to flush the joint space during or after operation of geared instrument  2 . Suction may also be used to remove tissue and excess fluids from the joint space. 
       FIG. 8  is a flowchart further illustrating one embodiment of a method  100  of performing a surgical procedure using the geared instrument  2  and distractor  26 . In step  102 , an MTP joint is prepared to receive the geared instrument  2 . Preparation of the MTP joint may include, for example, forming an incision (e.g., a superior incision). In step  104 , pins  22 ,  24  are inserted into the metatarsal  200  and proximal phalanx  202 , respectively. In some embodiments, the positioning of the pins  22 ,  24  may be guided using fluoroscopy or other imaging modalities to ensure that the distance between the pins  22 ,  24  and the end of the respective bone is appropriate. In step  106 , the distractor  26  is coupled to the pins. In step  108 , the distractor is used to separate the metatarsal  200  and the proximal phalanx  202 . In step  110 , the geared instrument  2  is inserted into the MTP joint. In step  112 , the shaft  4  of the geared instrument  2  is rotated, thereby rotating reamer  18  to remove cartilage and/or bone from the MTP joint and otherwise prepare the joint for fusion. While the shaft  4  is rotated, the arms  28 ,  30  of the distractor  26  may be moved toward one another such that the metatarsal  200  and proximal phalanx  202  move closer to allow the reamer  18  to remove additional material. 
     Alternatively, or additionally, in some embodiments, one of first pin  22  and second pin  24  is inserted into its respective bone. The distractor  26  is then engaged with the pin that is inserted into the bone. The distractor  26  is then used as a guide for insertion of the other of the first pin  22  and the second pin  24 . After placement of the pins  22 ,  24 , the procedure may be performed as described above. 
     In various embodiments, a geared instrument (e.g., instrument  2 ) and a distractor (e.g., distractor  26 ) may be provided together as a kit or system. This may simplify preparation for, and performance of, procedures, such as those described above. In addition, instruments and distractors of various sizes and configurations (e.g., left and right) may be provided together to accommodate the patient&#39;s anatomy or the user&#39;s preference. 
     While the foregoing description and drawings represent preferred or exemplary embodiments of the present invention, it will be understood that various additions, modifications and substitutions may be made therein without departing from the spirit and scope and range of equivalents of the accompanying claims. In particular, it will be clear to those skilled in the art that the present invention may be embodied in other forms, structures, arrangements, proportions, sizes, and with other elements, materials, and components, without departing from the spirit or essential characteristics thereof. One skilled in the art will further appreciate that the invention may be used with many modifications of structure, arrangement, proportions, sizes, materials, and components and otherwise, used in the practice of the invention, which are particularly adapted to specific environments and operative requirements without departing from the principles of the present invention. The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being defined by the appended claims and equivalents thereof, and not limited to the foregoing description or embodiments. Rather, the appended claims should be construed broadly, to include other variants and embodiments of the invention, which may be made by those skilled in the art without departing from the scope and range of equivalents of the invention. All patents and published patent applications identified herein are incorporated herein by reference in their entireties.