Apparatus and method for positioning an orthopaedic instrument
A number of orthopaedic surgical instruments are disclosed. A method, apparatus, and system for fabricating such instruments are also disclosed. In some embodiments, an orthopaedic instrument assembly may include a femoral cutting block configured to receive a portion of a distal femur of a patient and a ligament balancer secured to the femoral cutting block.
1 . An orthopaedic instrument assembly, comprising:
a femoral cutting block having (i) a negative contour surface that is configured to receive a portion of a distal femur of a patient that has a corresponding contour, and (ii) a cutting guide configured to guide a cutting tool to perform a resection of the distal femur of the patient, and
a ligament balancer comprising a bracket having a first end releasably secured to the femoral cutting block, wherein the ligament balancer has (i) a tibial base plate, and (ii) a pair of femoral paddles each of which is movable relative to the tibial base plate, and wherein the first end of the bracket has guide pin holes defined therein that are configured to receive guide pins secured into the distal femur of the patient.
2 . The orthopaedic instrument assembly of claim 1 , wherein a second end of the bracket is secured to the tibial base plate of the ligament balancer.
3 . The orthopaedic instrument assembly of claim 1 , wherein the guide pins are also received in guide pin holes of the femoral cutting block to secure the femoral cutting block to the distal femur of the patient.
4 . The orthopaedic instrument assembly of claim 1 , wherein:
the ligament balancer has a pair of cylinders secured to the tibial base plate, and
each of the pair of femoral paddles is received into a respective one of the pair of cylinders.
5 . A method of performing an orthopaedic surgical procedure on a knee joint of a patient, the method comprising:
inserting a portion of a ligament balancer between a femur of the patient and a tibia of the patient,
operating the ligament balancer to rotate the femur with respect to the tibia,
securing a femoral cutting block to the femur using a pair of guide pins, wherein the pair of guide pins are also received in a pair of apertures of the ligament balancer to releasably couple the femoral cutting block to the ligament balancer, and
moving a cutting tool along a cutting guide of the femoral cutting block to perform a resection of the femur.
6 . The method of claim 5 , wherein the ligament balancer comprises a bracket having (i) a first end that includes the pair of apertures and (ii) a second end coupled to the portion of the ligament balancer inserted between the femur and the tibia.
7 . The method of claim 5 , wherein operating the ligament balancer to rotate the femur with respect to the tibia comprises operating the ligament balancer to achieve a desired tension in the knee joint.
8 . The method of claim 5 , wherein inserting the portion of the ligament balancer between the femur and the tibia comprises:
placing a tibial base plate of the ligament balancer in contact with a proximal end of the tibia, and
placing at least one femoral paddle of the ligament balancer in contact with at least one condyle of the femur.
9 . The method of claim 8 , wherein placing the tibial base plate of the ligament balancer in contact with the proximal end of the tibia comprises positioning the tibial base plate on a resected surface of the tibia.
10 . The method of claim 8 , wherein operating the ligament balancer to rotate the femur with respect to the tibia comprises moving the at least one femoral paddle relative to the tibial base plate.
11 . The method of claim 5 , wherein inserting the portion of the ligament balancer between the femur and the tibia comprises:
placing a medial femoral paddle of the ligament balancer in contact with a medial condyle of the femur, and
placing a lateral femoral paddle of the ligament balancer in contact with a lateral condyle of the femur.
12 . The method of claim 11 , wherein operating the ligament balancer to rotate the femur with respect to the tibia comprises adjusting a displacement between the medial femoral paddle and the lateral femoral paddle.
13 . The method of claim 5 , wherein moving the cutting tool along the cutting guide of the femoral cutting block to perform the resection comprises performing a distal resection of the femur.
14 . The method of claim 5 , wherein moving the cutting tool along the cutting guide of the femoral cutting block to perform the resection comprises performing an anterior resection of the femur.
15 . An orthopaedic instrument assembly comprising:
a plurality of guide pins configured to be secured into a femur of a patient,
a ligament balancer comprising a medial femoral paddle configured to be positioned between a tibia of the patient and a medial condyle of the femur, a lateral femoral paddle configured to be positioned between the tibia and a lateral condyle of the femur, and a bracket extending away from the medial and lateral femoral paddles to a free end formed to include apertures configured to receive the plurality of guide pins, and
a femoral cutting block configured to be positioned on the femur, wherein the femoral cutting block is formed to include (i) guide holes configured to receive the plurality of guide pins to secure the femoral cutting block to the femur during a resection of the femur and (ii) a cutting guide configured to guide a cutting tool to perform the resection of the femur.
16 . The orthopaedic instrument assembly of claim 15 , wherein the ligament balancer further comprises a tibial base plate configured to be positioned in contact with a proximal end of the tibia, wherein the medial femoral paddle is configured to be positioned in contact with the medial condyle of the femur and is movable relative to the tibial base plate to adjust a medial gap between the tibia and the medial condyle of the femur, and wherein the lateral femoral paddle is configured to be positioned in contact with the lateral condyle of the femur and is movable relative to the tibial base plate to adjust a lateral gap between the tibia and the lateral condyle of the femur.
17 . The orthopaedic instrument assembly of claim 16 , wherein the bracket of the ligament balancer comprises (i) a distal end coupled to the tibial base plate and (ii) a proximal end opposite the distal end, wherein the apertures are formed in the proximal end of the bracket.
18 . The orthopaedic instrument assembly of claim 15 , wherein the cutting guide of the femoral cutting block is configured to guide the cutting tool to perform a distal resection of the femur.
19 . The orthopaedic instrument assembly of claim 15 , wherein the cutting guide of the femoral cutting block is configured to guide the cutting tool to perform an anterior resection of the femur.
20 . The orthopaedic instrument assembly of claim 15 , wherein the free end of the bracket of the ligament balancer is further formed to include a receiver configured to couple to an intramedullar rod positioned in the intramedullary canal of the femur.