1. A modular bone mill system (30) for converting bone stock into bone chips, the system comprising: a base module (32); and a milling module (60), said milling module comprising: a shell (34) adapted for releasable attachment to a base module (32) that includes a motor (38) and a sensor (54), the shell (34) having: an inlet opening (152) through which bone stock is introduced into the shell (34); an outlet opening (96) through which bone chips are discharged from the shell (34); and a milling element (170) disposed in the shell (34) between the inlet opening (152) and the outlet opening (96) for converting bone stock into bone chips, wherein the shell (34) includes: a lid (126) that is removably attached to a foundation (62), the lid (126) including the inlet opening (152) of the shell (34) and a first detection component (140) positioned to be detectable by the sensor (54) in the base module (32); and the foundation (62) being adapted for releasable attachment to the base module (32), the foundation (62) including the outlet opening (96) and a second detection component (236) and a catch tray (220) removably seated in the foundation (62) adjacent the outlet opening (96) to receive bone chips discharged therethrough, wherein the base module is configured to selectively power the milling element (170) of the milling module (60) based on whether the sensor (54) in the base module (32) detects that the first and second detection components (140, 236) are arranged relative to each other indicating that the lid (126) is correctly attached to the foundation (62), the catch tray (220) is correctly seated in the foundation (62), and the foundation (62) is correctly attached to the base module (32).
2. The modular bone mill system (30) of claim 1, wherein the first detection component (140) is mounted to the lid (126) and the second detection component (236) is mounted to the foundation, the base module including a single sensor for determining that the first and said second detection components (140, 236) are in registration with each other, which is indicative that the lid (126) is correctly secured to the foundation (62), the catch tray (220) is correctly seated in the foundation (62), and the foundation (62) is correctly attached to the base module (32).
3. The modular bone mill system (30) of claim 1 or 2, wherein the second detection component (236) of the foundation (62) is attached to the catch tray (220) and positioned to only be in registration with the first detection component (140) of the lid (126) when the catch tray (220) is correctly mounted to the foundation (62).
4. The modular bone mill system (30) of any one of claims 1-3, wherein: the first detection component is a magnet (140); and the second detection component (236) is formed from magnetically permeable material around which magnetic fields will develop.
5. The modular bone mill system (30) of any one of claims 1-4, wherein the milling element (170) includes: a cutting disc (172) with features (176) that convert bone stock into bone chips; and a shaft (186) that extends from the cutting disc (172) that is adapted to be held during removal of the milling element (170) from the foundation (62).
6. The modular bone mill system (30) of claim 5, wherein the shaft (186) extends from the cutting disc (172) and is formed with features (192) that removably couple the milling element (170) to the motor (38) of the base module (32).
7. The modular bone mill system (30) of claim 6, wherein the shaft (186) includes a head (188) and a stem (190) that extends downwardly from the head (188), wherein the stem (190) includes one or more notches (192) that extend upwardly from a bottom face of the stem (190) and are spaced radially outwardly from the center of the stem (190), wherein the one or more notches (192) are configured to engage one or more complementary teeth on a face of a drive spindle (40) of the base module (32) so that the rotation of the drive spindle (40) results in the like rotation of the milling element (170).
8. The modular bone mill system (30) of claim 7, wherein the cutting disc (172) includes one or more openings (174) which align with a complementary hole (175) on the head (188) of the shaft (186), wherein at least one pin (196) is positioned through one of said openings (174) and the complementary hole (175) such that the rotation of the shaft (186) results in the like rotation of the cutting disc (172).
9. The modular bone mill system (30) as set forth in any preceding claim, wherein the milling element (170) is removably attached to the foundation (62) of the shell (34).
10. The modular bone mill system (30) of any one of claims 1-9, wherein the lid (126) includes a domed, disc shaped cap (128) which defines an inner surface (129) and a side wall (131).
11. The modular bone mill system (30) of claim 10, wherein the cap (128) includes one or more tabs (130) that project radially outwardly from the cylindrical side wall of the cap, wherein the one or more tabs (130) are positioned and dimensioned so that when cap (128) is positioned in an opening (75) in the foundation (62) and rotated, each tab (130) rotates into a respective notch (106) in the foundation (62) to become integral with the notch (106) and correctly attach the lid (126) to the foundation (62).
12. The modular bone mill system (30) of claim 11, wherein one of the one or more tabs (130) includes a toe (138) having a magnet (140) disposed therein and extending downwardly from one end of tab (130), wherein when the cap (128) is positioned in an opening (75) in the foundation (62) and rotated to correctly attach the lid (126) to the foundation (62), the toe (138) moves into registration over an opening (112) in the foundation (62) when the lid (126) is correctly attached to the foundation (62).
13. The modular bone mill system (30) of claim 12, wherein the catch tray (220) includes a hollow sleeve (234) including a rod (236) with high magnetic permeability in the sleeve (234), wherein the components forming the milling module (60) are formed so that when the lid (126) is correctly secured to the foundation (62) and the catch tray (220) is correctly seated in the foundation (62), the rod (236) is located below the magnet (140).
14. The modular bone mill system (30) as set forth in any one of claims 10-13, wherein the cap (128) includes one or more rings (142, 144, and 146) which extend downwardly from the inner surface (129) of the cap (128); and/or wherein the cap (128) includes one or more ribs (143, 145) extending downwardly from the inner surface (129) of the cap (128), the ribs (143, 145) configured to push bone stock into a cutting disc (172) of the milling element (170) and prevent bone stock from accumulating on the inner surface (129) of the cap (128) when the bone mill is in operation.
15. The modular bone mill system (30) of any one of claims 1-14, wherein the foundation (62) includes a rim (64) having plural openings (66) and is dimensioned to seat around an outer perimeter of a top surface (36) of the base module (32), wherein when the milling module (60) is seated over the base module (32) top surface (36), plural tabs (44) on the base module (32) extend through the plural openings (66) to become integral with the plural opening (66) and correctly attach the milling module (60) to the base module (32).
