Cam based rod connection system and method
In one of many possible embodiments, the present exemplary system provides a connection member for coupling to one or more structural rods including a coupler body defining a first recess sized to receive the structural rod, and a cam mechanism positioned adjacent to the first recess, wherein the cam mechanism is configured to selectively vary a size of the first recess to couple the structural rod in the first recess.
1 . A coupler for coupling an orthopedic rod, comprising:
a coupler body defining a first recess sized to receive said orthopedic rod; and
a cam mechanism positioned adjacent to said first recess, wherein said cam mechanism is configured to selectively vary a size of said first recess to couple said orthopedic rod in said first recess.
2 . The coupler of claim 1 , wherein said cam mechanism is rotatably coupled to said coupler body.
3 . The coupler of claim 1 , wherein said cam mechanism comprises a lobed cam screw.
4 . The coupler of claim 1 , wherein said cam mechanism comprises a helical cam screw.
5 . The coupler of claim 1 , further comprising a second recess defined by said coupler body;
wherein said first recess is sized to receive a first orthopedic rod;
wherein said second recess is sized to receive a second orthopedic rod; and
wherein said cam mechanism is disposed in said coupler body between said first recess and said second recess, said cam mechanism being configured to simultaneously reduce a size of said first and said second recess upon rotation of said cam mechanism.
6 . The coupler of claim 5 , wherein said first recess is a different size than said second recess.
7 . The coupler of claim 5 , further comprising a retaining member configured to maintain said cam mechanism in said coupler body.
8 . The coupler of claim 7 , wherein said retaining member comprises one of a pin or a set screw.
9 . The coupler of claim 5 , wherein said cam mechanism further comprises a driving feature formed in a first end of said cam mechanism.
10 . The coupler of claim 9 , wherein said cam mechanism further comprises a second driving feature formed in a second end of said cam mechanism.
11 . The coupler of claim 1 , further comprising an orifice including a recess defined by said coupler body;
wherein said orifice is configured to receive a screw head of a screw; and
wherein said cam mechanism is positioned to urge an orthopedic rod disposed in said first recess against said screw head to seat said screw head in said recess.
12 . The coupler of claim 11 , wherein said cam mechanism is rotatable to a first position to retain said orthopedic rod between said cam mechanism and said screw head.
13 . The coupler of claim 12 , wherein said cam mechanism is rotatable to a second position to fixedly retain said orthopedic rod between said cam mechanism and said screw head.
14 . The coupler of claim 1 , further comprising a hook member coupled to said coupler body, wherein said hook member is configured to engage a posterior element of a vertebra.
15 . The coupler of claim 14 , wherein said cam screw comprises a helical cam screw.
16 . A coupler for coupling a first orthopedic rod to a second orthopedic rod, comprising:
a coupler body including a first slot and a second slot, said first slot configured to receive said first orthopedic rod and said second slot being configured to receive said second orthopedic rod; and
a cam mechanism positioned between said first slot and said second slot;
wherein said cam mechanism is configured to, when rotated, simultaneously reduce a size of said first slot and said second slot to retain said first orthopedic rod and said second orthopedic rod.
17 . The coupler of claim 16 , wherein said cam mechanism comprises:
a first recess in a first end of said cam mechanism, said first recess being configured to receive a driving tool; and
a second recess in a second end of said cam mechanism, said second recess being configured to receive said driving tool.
18 . An assembly comprising:
a coupler having a first opening to receive a screw head of a screw, a slot positioned adjacent to said first opening, a recess adjacent to the slot; and
a cam mechanism positioned in the recess and rotatable to urge a spinal rod located in the slot against the screw head.
19 . The assembly of claim 18 , wherein said coupler further comprises a wall extending from said first opening, said wall being configured to abut said screw head when said cam mechanism is positioned to urge said spinal rod against said screw head.
20 . A coupler for coupling an orthopedic rod, comprising:
a coupler body defining a first recess sized to receive said orthopedic rod;
a cam mechanism positioned adjacent to said first recess, wherein said cam mechanism is configured to selectively vary a size of said first recess to couple said orthopedic rod in said first recess; and
a hook member coupled to said coupler body, wherein said hook member is configured to engage a posterior element of a vertebra.
21 . The coupler of claim 20 , wherein said cam screw comprises a helical cam screw.
22 . A method for coupling an orthopedic rod to a housing comprising:
receiving said orthopedic rod in a first slot of said housing; and
rotating a cam mechanism to frictionally engage said rod in said housing.
23 . The method of claim 22 , wherein said rotating said cam mechanism further comprises forcing said rod against a head of a screw to seat said head of a screw in said housing.
24 . The method of claim 22 , further comprising receiving a second orthopedic rod in a second slot of said housing, wherein rotating said cam mechanism reduces a size of said first slot and said second slot, frictionally engaging both said first orthopedic rod and said second orthopedic rod in said housing.