Bone graft material loading assembly and associated devices, systems, and methods

1. A bone graft loading device, comprising:

a syringe defining a reservoir, the syringe comprising a nozzle at a distal portion of the syringe and an opening at a proximal portion of the syringe;

a plunger configured to force bone graft material from the reservoir through the nozzle, wherein the plunger comprises:

a plunger body positioned at least partially within the syringe and defining a lumen, wherein the plunger body comprises a threaded portion and a distal portion coupled to the threaded portion;

a handle coupled to a proximal end of the plunger body and positioned outside the reservoir;

a cap coupled to the proximal portion of the syringe, wherein the cap comprises a threaded portion configured to engage with the threaded portion of the plunger body; and

a tamp positioned within the lumen of the plunger body and configured to protrude distally of the plunger through the nozzle,

wherein an outer surface of the plunger mates with an inner wall of the syringe, and

wherein an inner surface of the plunger mates with the tamp to block passage of the bone graft material into the lumen of the plunger body.

2. The bone graft loading device of claim 1 , wherein the plunger comprises a stopper coupled to a distal end of the plunger body, wherein the stopper comprises:

the outer surface of the plunger mating with the inner wall of the syringe; and

the inner surface of the plunger mating with the tamp.

3. The bone graft loading device of claim 1 , wherein at least the distal portion of the plunger body extends within the syringe.

4. The bone graft loading device of claim 1 , wherein, in a retracted position, at least part of the threaded portion is positioned outside of the syringe.

5. The bone graft loading device of claim 1 , wherein the distal portion of the plunger body comprises a flange.

6. The bone graft loading device of claim 1 , further comprising a spring coupled to the tamp and the plunger, wherein the spring is configured to bias the tamp in a proximal direction relative to the plunger.

7. The bone graft loading device of claim 6 , wherein:

the tamp comprises a widened section and a distal section,

wherein a cross-sectional size of the widened section is greater than a cross-sectional size of the distal section,

wherein the plunger body comprises a first retention feature around the lumen of the plunger body, and

wherein the spring is positioned around the distal section of the tamp and extends between the first retention feature of the plunger body and the widened section of the tamp.

8. The bone graft loading device of claim 7 , wherein the plunger comprises a second retention feature proximal of the first retention feature, and wherein second retention feature is configured to abut a surface of the widened section of the tamp to retain the tamp within the lumen of the plunger body.

9. The bone graft loading device of claim 1 , wherein the syringe comprises a finger grip feature protruding from an external surface of the syringe.

10. The bone graft loading device of claim 1 , wherein the tamp is configured to advance distally relative to the plunger by a first distance to a second position, and wherein a distal end of the tamp is spaced from the nozzle by a distance greater than a first amount when the plunger is in a first position relative to the syringe.

11. The bone graft loading device of claim 10 , wherein the first distance is between 1.0 in. and 2.0 in.

12. The bone graft loading device of claim 1 , wherein a proximal section of the tamp extends proximally of the lumen of the plunger body, and wherein a tamp cap is coupled to the proximal section of the tamp.

13. The bone graft loading device of claim 12 , wherein the tamp cap is positioned proximally of the handle of the plunger and is movable independently of the handle.

14. A method for loading a bone graft injection cannula, comprising:

coupling the cannula to a syringe defining a reservoir, the syringe comprising a nozzle at a distal portion of the syringe and an opening at a proximal portion of the syringe;

placing bone graft material within the reservoir;

providing a plunging assembly that comprises:

a plunger body defining a lumen, wherein the plunger body comprises a threaded portion and a distal portion coupled to the threaded portion;

a handle coupled to a proximal end of the plunger body;

a cap coupled to the proximal portion of the syringe, wherein the cap comprises a threaded portion configured to engage with the threaded portion of the plunger body; and

a tamp extending within the lumen of the plunger body, wherein the tamp is movable relative to the plunger body, and wherein the tamp is biased proximally relative to the plunger body;

coupling the plunging assembly to the syringe such that the plunger body is positioned within the reservoir through the opening at the proximal portion, wherein an outer surface of the plunger body is configured to form a first sliding seal with the reservoir wherein an inner surface of the plunger is configured to form a second sliding seal with the tamp; and

rotating the handle of the plunging assembly to move the bone graft material toward the nozzle;

pushing the tamp toward the nozzle such that a distal end of the tamp protrudes distally of the plunger body to force the bone graft material through the nozzle and into the cannula.

15. A bone graft loading device, comprising:

a syringe defining a reservoir, the syringe comprising a nozzle at a distal portion of the syringe and an opening at a proximal portion of the syringe, wherein the syringe comprises a first cylindrical portion comprising a first diameter, and wherein the nozzle comprises a second cylindrical portion comprising a smaller second diameter;

a plunger configured to force bone graft material from the reservoir through the nozzle, wherein the plunger comprises:

a plunger body positioned at least partially within the syringe and defining a lumen, wherein the plunger body comprises a threaded portion and a distal portion coupled to the threaded portion;

a handle coupled to a proximal end of the plunger body and positioned outside the reservoir;

a cap coupled to the proximal portion of the syringe, wherein the cap comprises a threaded portion configured to engage with the threaded portion of the plunger body; and

a tamp positioned within the lumen of the plunger body and configured to protrude distally of the plunger into the second cylindrical portion comprising the smaller second diameter.