Surgical system

1. A surgical system comprising:

an instrument portal comprising a first proximal end, a first distal end, and a first elongated member, the first elongated member defining a first bore having a first diameter, wherein the first bore extends from the first distal end to the first proximal end, wherein the maximum clearance of the instrument portal is the first diameter;

a drill guide reducer configured to be inserted into the instrument portal, the drill guide reducer comprising an elongated cylindrical member defining an outside diameter that is smaller than the first diameter, such that the drill guide reducer is sized to fit within the instrument portal and defining an inner diameter configured to receive a drill guide, wherein the inner diameter of the drill guide reducer is smaller than the first diameter of the instrument portal;

an anchor pin receiving chamber positioned outside of the first elongated member and fixed in parallel to the instrument portal comprising a second proximal end, a second distal end, and a second elongated member comprising a second bore, the second bore defining a second diameter, wherein the second bore extends from the second distal end to the second proximal end, and wherein the second diameter is smaller than the first diameter; and

an anchor pin to be inserted into the anchor pin receiving chamber for anchoring the system to a vertebral lateral mass or a pedicle, the anchor pin comprising an elongated member, a proximal stopping knob, and a proximal protruding end, wherein a distal protruding end extends past the second distal end when the anchor pin is located within the anchor pin receiving chamber.

2. The system of claim 1 , further comprising:

an inner cannula to be inserted into the instrument portal for advancing the MIS apparatus toward a vertebral lateral mass or a pedicle, the inner cannula comprising a proximal end, a distal end, and an elongated member defining an outer diameter sized to fit within the instrument portal.

3. The system of claim 2 , wherein the distal end of the inner cannula is tapered.

4. The system of claim 2 , wherein the inner cannula is radiopaque.

5. The system of claim 2 , wherein the inner cannula is sized to fit against an inner surface of the instrument portal.

6. The system of claim 1 further comprising:

a screw reducer to be inserted into the instrument portal to accommodate a head of a screw, the screw reducer comprising an elongated cylindrical member sized to fit within the instrument portal and an inner opening sized to fit the head of the screw, wherein the head of the screw defines an outer diameter that is smaller than the first diameter.

7. The system of claim 1 , wherein the instrument portal is radiolucent.

8. The system of claim 1 , wherein the first distal end includes an oblique end contoured to fit against a vertebral lateral mass or a pedicle.

9. A surgical apparatus comprising:

an instrument portal comprising a first proximal end, a first distal end, and a first elongated member, the first elongated member comprising a first cylindrical bore defining a first diameter, wherein the first cylindrical bore extends from the first distal end to the first proximal end, wherein the maximum clearance of the instrument portal is the first diameter;

a screw reducer located within the instrument portal to accommodate a head of a screw, the screw reducer comprising an elongated cylindrical member sized to fit within the instrument portal and an opening defining an inner diameter sized to fit the head of the screw, wherein the head of the screw defines a diameter that is smaller than the first diameter;

an anchor pin receiving chamber positioned adjacent the first elongated member and fixed in parallel to the instrument portal;

a drill guide reducer configured to be inserted into the instrument portal, the drill guide reducer comprising an elongated cylindrical member defining an outside diameter such that the drill guide reducer is sized to fit within the instrument portal and defining an inner diameter configured to receive a drill guide, wherein the inner diameter of the drill guide reducer is less than the first diameter; and

an anchor pin located within the anchor pin receiving chamber for anchoring the apparatus to the vertebral lateral mass or a pedicle, the anchor pin comprising an elongated member, a proximal stopping knob, and a proximal protruding end, wherein the proximal protruding end extends past the second distal end to engage the vertebral lateral mass or a pedicle.

10. The apparatus of claim 9 , wherein the instrument portal is radiolucent.

11. The apparatus of claim 9 , wherein the first distal end includes an oblique end contoured to fit against a vertebral lateral mass or a pedicle.

12. The apparatus of claim 9 , wherein the drill guide reducer reduces the maximum clearance of the instrument portal.

13. The apparatus of claim 9 , wherein the instrument portal comprises a second proximal end, a second distal end, and a second elongated member, the second elongated member comprising a second cylindrical bore defining a second diameter, wherein the second cylindrical bore extends from the second distal end to the second proximal end, and wherein the second diameter is smaller than the first diameter.

14. The apparatus of claim 9 , further a handle coupled to at least one of an outer surface of the instrument portal or an outer surface of the anchor pin receiving chamber.