Instruments and methods for delivering multiple implants in a surgical procedure

Instruments and methods are provided for delivering multiple implants to locations for implantation in a patient without requiring a second implant to be loaded onto or engaged to the delivery instrument after delivery of a first implant.

BACKGROUND

Various types of devices and systems have been used for positioning implants into a patient in surgical procedures. Spinal stabilization systems have employed plating systems, rods, anchors, fusions devices, artificial discs, and other implants along or in the spinal column for rigid, dynamic, and semi-rigid spinal stabilization procedures. Such systems often include multiple implant members that must be engaged for the system to be properly installed. There remains a need for instruments and methods for delivering multiple implants to the implantation location while minimizing the time and complexity associated with handling and positioning such implants during surgery.

SUMMARY

According to one aspect, an instrument for delivering multiple implants to at least one surgical location in a patient includes a mounting member, a retaining mechanism housed in the mounting member, and an actuator coupled to the mounting member. The mounting member includes an elongate tubular portion extending between a distal mounting portion for receiving multiple implants therealong and a proximal end member. The retaining mechanism is movable between a retaining position for retaining the implants along the mounting portion and a dispensing position allowing a distal-most implant on the mounting portion to move distally along the mounting portion for delivery to the at least one surgical location. The actuator includes a proximal engaging end adjacent the proximal end member of the mounting member. The actuator extends from the proximal engaging end through the tubular portion to an actuating end along the mounting portion. The actuator includes a first axial position with the actuating end positioning the retaining mechanism in the retaining position. The actuator is movable in the mounting member to a second axial position with the actuating end positioning the retaining mechanism in the dispensing position.

According to another aspect, an instrument for delivering multiple implants to at least one surgical location in a patient includes a mounting member, an actuator in the mounting member, and distal and proximal retaining members in the mounting member in contact with the actuator. The mounting member includes an elongate tubular portion extending between a distal mounting portion for receiving multiple implants therealong and a proximal end member. The actuator includes a distal actuating end in the tubular portion of the mounting member and a proximal engaging end received in the end member of the mounting member. The actuator has a first rotational alignment relative to the mounting member wherein the actuator is axially movable in the mounting member between a retaining position and a dispensing position. In the retaining position the distal retaining member projects outwardly from the mounting portion and contacts a distal-most implant to axially retain the multiple implants on the mounting portion and the proximal retaining member is recessed in the mounting portion. In the dispensing position the distal retaining member is recessed into the mounting portion to permit the distal-most implant to advance distally along the mounting portion for implantation and the proximal retaining member projects outwardly from the mounting portion to contact a second implant proximal of the distal-most implant to axially retain the second implant on the mounting portion.

In another aspect, a surgical system includes a delivery instrument and multiple implants along the delivery instrument. The delivery instrument includes an elongated mounting member having a distal mounting portion and a proximal end member, an actuator in the mounting member including an actuating end in the mounting portion and a proximal engaging end extending proximally from the proximal end member of the mounting member, and a retaining mechanism in the mounting member movable upon axial displacement of the actuator in the mounting member between a retaining position and a dispensing position. The plurality of implants positioned about the mounting portion include a distal-most implant in contact with the retaining mechanism in the retaining position and a proximal most implant in contact with a biasing member biasing the multiple implants distally into contact with the retaining mechanism.

In yet another aspect, a method for delivering multiple implants to an implantation location comprises: positioning a distal end of a delivery instrument at a first implantation location, the delivery instrument including a first distal-most implant and at least one second implant proximal the first implant positioned about and retained on the delivery instrument; distally advancing the first implant along the delivery instrument for implantation at the implantation location while simultaneously retaining the at least one second implant on the delivery instrument with the delivery instrument; positioning the distal end of the delivery instrument adjacent a second implantation location; and distally advancing the at least one second implant along the delivery instrument for implantation at the second implantation location.

These and other aspects will also be apparent from the following description.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Positioning of multiple implants during a surgical procedure without withdrawing or re-loading the delivery instrument with an implant is facilitated by a delivery instrument that includes a mounting member with multiple implants positioned axially therealong. The multiple implants are axially retained on the mounting portion until positioned adjacent an implantation location. The instrument can be actuated to deliver the distal-most implant from the distal end of the delivery instrument to the implantation location while the next most distal implant is axially retained on the mounting portion. The delivery instrument can then be re-positioned, or maintained in the same position, for delivery of the second implant from the distal end by actuating the delivery instrument. The process can be repeated until all required implants have been delivered or until it is necessary to re-load the delivery instrument with additional implants.

The delivery instrument can include an actuator that is operable at the proximal end of the delivery instrument to effect delivery and retention of the implants along the distal mounting portion of the delivery instrument. In one embodiment, the actuator includes a dispensing orientation that provides a push-button type control to dispense the implants from the delivery instrument. The actuator is moveable to a loading orientation that allows multiple implants to be loaded about the mounting portion from the distal end of the instrument. After loading of the implants, the actuator is movable to the dispensing orientation where the implants are retained on the mounting portion until the actuator is depressed by the user to deliver the distal-most implant.

The implantation location can be an implant engageable to bony structure of the patient, such as a spinal plate, a bone screw, a clamp, an interbody device, or any other construct. In one specific technique, the implantation location is a proximally extending post of a bone screw, and the implant is a washer that is positionable about the post. Multiple implants can be delivered to the same location, or to multiple locations in the patient. The washers can facilitate securement of a plate or rod to the bone screw post in a desired position therewith.

InFIGS. 1-4there is shown a delivery instrument10extending along a longitudinal axis11between a distal mounting end16about which multiple implants can be mounted and a proximal actuating end18to effectuate delivery of the implants from distal mounting end16. In the illustrated embodiment delivery instrument10includes a housing20to which a mounting member40is mounted. Mounting member40extends through housing20between a proximal end member42proximal of housing20and a distal mounting portion44distal of housing20. Multiple implants14(FIG. 5) can be mounted about distal shaft portion44and retained thereon with a retaining mechanism120. Retaining mechanism120is movable with an actuator70between a retaining position to retain the implants on mounting portion44and a dispensing position where the distal-most implant is movable axially along mounting portion44for delivery from the distal end of delivery instrument10.

Actuator70extends through mounting member40between a proximal user engaging end72and a distal actuating end74in mounting member40. Engaging end72can be manipulated by the user to selectively move actuator70in mounting member40so that actuating end74selectively deploys and recesses retaining mechanism120between the retaining position and the dispensing position.

Delivery instrument10further includes a piston member30movably received in housing20and about mounting member40that is distally biased along mounting member40and into contact with the implants along mounting portion44. Piston member30is axially restrained in the distal direction by a distally oriented outer lip about piston member30adjacent its proximal end that contacts with a proximally oriented inner lip about housing20adjacent its distal end.

In the dispensing orientation actuator70is proximally biased in mounting member40when in a first rotational alignment therewith so that it is normally in a retaining position. The user can move actuator70axially by pressing engaging end72distally in mounting member40to a dispense position. In the dispensing position actuating end74is configured and positioned to manipulate retaining mechanism120so that distal-most implant is movable distally along mounting portion44for delivery therefrom while the next most distal implant is axially retained on mounting portion44by retaining mechanism120. The distally directed force supplied by piston member30can assist in advancing the implants distally along mounting portion44, although embodiments without piston member are contemplated where the implants advance solely due to gravity.

In the loading orientation, actuator70can further be configured so that when it is in a second rotational alignment with mounting member40the retaining mechanism120is positioned to allow implants to be axially loaded into mounting portion44. In this loading position, actuating end74is configured and position relative to retaining mechanism120so that it is recessed in mounting member40, allowing implants to be loaded about mounting member40without interference from retaining mechanism120. Piston member30can be manually restrained in a proximal position about mounting member40as the implants are loaded along mounting portion44. When actuator70is returned to its first rotational alignment in mounting member40in the dispensing orientation, piston30can be released to contact the proximal most implant and bias the multiple implants distally into contact with retaining mechanism120in its retaining position.

Further details of operation of actuator70to dispense and load implants about mounting member40are shown inFIGS. 5A-6B. InFIG. 5A, actuator70is positioned in the dispensing orientation relative to mounting member40. An arrow or other indicator can be provided on the proximal end of actuator70that can align with the word “DISPENSE” or some other indicator on the side of mounting member40to provide the user an indication that delivery instrument10is rotationally aligned with mounting member40in an orientation that allows actuator70to be axially moved from the retaining position to the dispensing position. When in this first rotational alignment, the distal actuating end74is positioned in a first axial position relative to retaining members120a,120bof retaining mechanism120, as shown inFIG. 5B. In this first axial position, actuating end74contacts retaining members120a,120bto maintain retaining members120a,120bin the retaining position. In the illustrated embodiment, retaining members120a,120bare ball-shaped members that are sized relative to detents44a,44bto project therefrom when bottomed out in the respective detents44a,44b, but are too large to pass through detents44a,44b.

In the retaining position ofFIG. 5B, proximal retaining member120bis aligned with a retaining member recess76in actuating end74so that it can recess into proximal detent44bof mounting portion44and not project outwardly from the outer surface of mounting portion44. Distal retaining member120a, on the other hand, is in contact with a distal actuating shaft portion75of actuating end74and forced into distal detent44aso that distal retaining member120aprojects outwardly from the outer surface of mounting portion44. Distal retaining member120athus prevents implants14a,14babout mounting portion44from sliding distally along mounting portion44. Implant14acan be located distally of the proximal retaining member120b. The distal end of the second most distal implant14b, however, is located proximally of proximal retaining member120b. Piston member30pushes against the proximal-most implant and forces the distal-most implant14ainto contact with retaining member120and the remaining implants into end-to-end contact with one another along mounting portion44.

In the retaining position ofFIG. 5B, a distal end member130of actuator70contacts a distal end wall of mounting member40, maintaining the proximally biased actuator70in the retaining position. Actuator70can be axially moved toward the dispensing position by axially and distally displacing actuator70in mounting member40, as shown inFIG. 5C, locating actuating end74in a second axial position relative to mounting portion44and spacing distal end member130a distance d from a distally oriented end wall of mounting member40. In the dispensing position ofFIG. 5C, distal retaining member120ais aligned with retaining member recess76in actuating end74so that it can recess into distal detent44aof mounting portion44and not project outwardly from the outer surface of mounting portion44. Distal implant14acan thus move distally along mounting portion44by gravity and/or the bias of piston member30for delivery therefrom. Proximal retaining member120b, on the other hand, is in contact with a proximal actuating shaft portion77of actuating end74and pushed into proximal detent44bsufficiently to project outwardly from the outer surface of mounting portion44. Proximal retaining member120bthus prevents the next most distal implant14babout mounting portion44from sliding distally along mounting portion44when the distal-most implant is being delivered.

When the proximal end of actuator70is released, it is spring biased proximally to return actuating end74to its first axial position and to the retaining position shown inFIG. 5B. The next most distal implant14bmoves distally along mounting portion44via gravity and/or the bias from piston member30to contact distal retaining member120a, while proximal retaining member120brecesses into mounting portion44. The process can be repeated for each implant14to be dispensed from mounting portion44of mounting member40.

FIGS. 6A and 6Bshow actuator70positioned in a second rotational alignment with mounting member40in a loading orientation to permit loading of implants onto mounting portion44of mounting member40. InFIG. 6A, the proximal end of actuator70is rotated relative to mounting member40180 degrees from its orientation inFIGS. 5A-5C. Mounting member40can be inscribed with the word “LOAD” or include some other indicator to indicate that actuator70is in the loading orientation when the arrow is aligned therewith. In one embodiment, actuator70is pressed distally against the proximal bias thereof, and is then rotated to position an alignment pin110in a keyed portion of actuator70. The engagement of alignment pin110in the keyed portion of actuator70allows alignment pin110to maintain actuator70in its distally displaced position relative to mounting member40without the application of manual pressure at the proximal end of actuator70to overcome the proximal bias of actuator70.

As shown inFIG. 6B, in the loading position distal end member130is spaced distance d from the distally oriented end wall of mounting member40. Actuating end74includes an elongated recess78that is aligned with detents44a,44b. Elongated recess78is configured to permit both retaining members120a,120bto simultaneously recess into mounting member40, avoiding interference with the loading of implants14about mounting portion44. Piston member30can be grasped and pulled proximally into housing20against the distal bias of piston member30to allow the implants to be positioned along mounting portion44. After loading of the implants, actuator70is rotated to its first rotational alignment with mounting member40, where it automatically returns toward the position ofFIGS. 5A and 5Bto retain the loaded implants on mounting portion44. Piston member30can then be released to contact the proximal most implant14along mounting portion44and force the distal-most implant14into contact with distal retaining member120a.

Further details of the components of delivery instrument10are shown inFIG. 7-13. InFIG. 7mounting member40is shown in longitudinal section view. Mounting member40includes proximal end member42defining a cylindrical receptacle43for receiving a proximal portion of actuator70, as discussed further below. A number of holes can be provided about end member42to facilitate longitudinal movement of actuator70therein without build-up of resistive air pressure. Mounting member40further includes a threaded collar46adjacent end member42, and an elongated tubular portion48extending distally from collar46. Tubular portion48defines a passage49extending therethrough that opens into the receptacle43defined by end member42and at the distal end of tubular portion48.

The distal end of mounting member40includes a threaded tip portion52for threadingly receiving positioning member140thereabout, as shown inFIG. 5Bfor example. Positioning member140includes a proximal internally threaded portion142engageable about tip portion52and a distally extending locator tip144. Locator tip144includes a reduced diameter or size relative to proximal portion142and mounting member40, and can be positioned in an implant receptacle or other structure at the surgical site to assist in positioning delivery instrument10in the desired position and orientation relative to the implantation location. In one embodiment, locator tip144is smaller in size than mounting portion44to assist in placing delivery instrument10in overlapping relation with the implantation location. For example, locator tip144can be placed in a tool recess in a proximal end of a bone anchor. The implants can be delivered to the bone anchor without slipping off, fall between or otherwise misaligning with the bone anchor as the implant slides off positioning member140.

Passage49can includes a proximal portion49band a reduced size distal portion49a. Detents44a,44bare located through the wall of tubular portion48in communication with distal passage portion49a. Actuator70, shown also inFIGS. 8-10, includes an elongated proximal shaft portion80that is received in proximal portion49bof passage49and distal actuating end74that is received in distal portion49aof passage49. The axial positioning of recesses76,78and shaft actuating portions75,77relative to detents44a,44bto effect deployment and recessing of retaining members120a,120bis discussed above. Actuating end74includes a threaded distal tip82for threadingly engaging end cap130. End cap130can abuttingly engage the adjacent distally oriented wall of mounting member40to assist in maintaining actuator70in the retaining position shown inFIG. 5B.

Proximal user engaging end72of actuator70includes a gripping portion84and a cylindrical portion86extending from gripping portion84to shaft portion80. Gripping portion84can be tapered in at least one dimension to narrow proximally and can be concavely curved to facilitate gripping by the user to apply the rotational and axial forces to actuator70. Cylindrical portion86is rotatably received in receptacle43defined by end member42of mounting member40. Actuator biasing member100(FIGS. 1-4) can be a spring positioned about shaft portion80and into contact with the distally oriented wall87of cylindrical portion86. Biasing member100also contacts a proximally oriented wall56in end member42to normally bias actuator70proximally relative to mounting member40.

Alignment pin110(shown inFIG. 13) includes an outer portion114engaged in hole54of end member42and an inner portion112positioned in a keyway in cylindrical portion86. The keyway is formed by an axial slot portion86aand a transverse slot portion86bat the proximal end of axial slot portion86a. Inner portion112is received in axial slot portion86awhen delivery instrument10is rotationally aligned in the dispensing orientation. With biasing member100normally biasing actuator70proximally relative to mounting member40, alignment pin110normally resides at the distal end of axial slot86a, positioning actuating end74and retaining mechanism120in mounting member40to the retaining position as shown inFIG. 5B.

To advance actuating member70and place actuating end74and retaining mechanism120in the dispensing position as shown inFIG. 5C, user engaging end72is depressed against the bias of biasing member100, and alignment pin110moves along axial slot portion86ato its proximal end. If it is desired to position delivery instrument10in the loading orientation, then from the dispensing position gripping portion84can be gripped to rotate actuator70in mounting member40, advancing alignment pin110into transverse slot portion86b. When alignment pin110has been translated to the end of transverse slot portion86bopposite axial slot portion86a, actuator70is maintained in the depressed condition against the bias of biasing member100, and actuating end74is maintained in the axial and rotational position shown inFIG. 6Bto permit loading of implants about mounting portion44.

Housing20is shown in longitudinal section view inFIG. 11. Housing20includes a longitudinal bore21extending between and opening through a distal end22and a proximal end24. Proximal end24includes internal threads26to threadingly engage collar46of mounting member40. Distal end22includes an internal lip28extending thereabout.

Piston member30is shown inFIG. 12, and includes an elongated body extending between a distal end32and a proximal end34. Piston member30includes a central bore31sized for positioning about tubular portion48of mounting member40. Piston member30can include a number of elongated slots36extending therethrough and spaced radially thereabout to facilitate movement of piston member30between housing20and mounting member40. Piston biasing member90can be in the form of a spring positioned about tubular portion48with a distal end of piston biasing member90in contact with proximal end34of piston member30, and a proximal end of piston biasing member90in contact with collar46.

Biasing member90pushes piston member30against the proximal-most implant14and forces the distal-most implant14into contact with retaining mechanism120. Piston member30further includes an external lip38adjacent proximal end34that contacts internal lip28of housing20adjacent the distal end of housing20. Contact between the lips28,38retains piston member30about tubular portion48of mounting member40even when piston member30is fully extended distally from housing20under the force of biasing member90, as shown inFIGS. 1 and 2.