Apparatus and method for connecting surgical rods
View Patent ↗An exemplary apparatus for connecting surgical rods according the principles of the present disclosure includes an elongate first arm, an elongate second arm, and a clamping assembly. The elongate first arm includes a first end that couples with a first rod and a second end with a first engagement portion. The elongate second arm includes a first end that couples with a second rod and a second end terminating in a second engagement portion. The clamping assembly includes a passageway that slidably receives the first engagement portion and that retains the second engagement portion and an adjustment member offset from the passageway that adjusts a clamping force to restrict positioning of the second engagement portion relative to the first engagement portion.
1. An apparatus for connecting surgical rods, comprising:
a first arm including a first end with a first hook configured to couple with a first rod and a second end with a first engagement portion comprising a curved channel in an upper surface and terminating in a lip in a lower surface;
a second arm including a first end with a second hook configured to couple with a second rod and second end with a second engagement portion terminating in an upper hemispherical portion with a first radius and a lower hemispherical portion with a second radius greater than the first radius; and
a clamp assembly including
an upper portion, a side portion, and a lower portion that form a C-shaped collar with a passageway therethrough, the lower portion slidably engageable with a lower surface of the first engagement portion and the upper portion including a hemispherical recess in a lower surface configured to retain the upper hemispherical portion of the second engagement portion;
an aperture extending through the upper portion and the lower portion, offset from a transverse centerline extending through the first arm and the second arm, and on an opposite side of the first and second engagement portions at the side portion; and
an adjustment member within the aperture that adjusts a clamping force on the first engagement portion and the second engagement portion to restrict positioning of the second arm relative to the first arm.
2. The apparatus of claim 1 , wherein the curved channel includes a routed portion of the upper surface having a radius configured to receive the lower hemispherical portion with the second radius.
3. The apparatus of claim 1 , wherein the adjustment member extends through the aperture without contacting the first arm and the second arm.
4. The apparatus of claim 1 , wherein the second arm further comprises a pair of flat surfaces adjacent the upper hemispherical portion and that engages the lower surface of the upper portion of the collar to restrict rotation about a longitudinal axis of the second arm.
5. The apparatus of claim 1 , wherein the lower hemispherical portion of the second engagement portion translates within the curved channel of the first arm to adjust a length of the apparatus.
6. The apparatus of claim 1 , wherein the second arm rotates about a longitudinal axis of the second arm.
7. The apparatus of claim 1 , wherein the second arm pivots about a common axis extending through the upper hemispherical portion and the lower hemispherical portion.
8. The apparatus of claim 1 , wherein the lip of the first arm engages the lower portion of the collar to retain the first arm within the passageway.
9. The apparatus of claim 1 , further comprising chamfered edges around the aperture in an upper surface of the upper portion of the clamping collar and a threaded section in the aperture of the lower portion to receive threads of the adjustment member.
10. The apparatus of claim 1 , further comprising a first rod aperture in the first hook configured to receive a first rod setscrew to couple with the first rod.
11. The apparatus of claim 1 , further comprising a second rod aperture in the second hook configured to receive a second rod setscrew to couple with the second rod.
12. The apparatus of claim 1 , wherein the aperture does not intersect the passageway.
13. The apparatus of claim 1 , wherein the adjustment member does not engage the first arm and the second arm.