Customized acetabular cup positioning guide and system and method of generating and employing such a guide

A method of manufacturing a custom acetabular cup positioning guide for use in an arthroplasty procedure involving a hip region of a patient's body, wherein the hip region includes the patient's femoral head, femoral neck and acetabular cup, the guide including a mating region configured to matingly receive a portion of the patient's acetabular cup, the mating region including a surface contour that is generally a negative of a surface contour of the patient's acetabular cup, the surface contour of the mating region being configured to mate with the surface contour of the patient's acetabular cup in a generally matching or interdigitating manner when the patient's acetabular cup is matingly received by the mating region, the method of manufacture comprising:

• a) generating medical imaging slices of the portion of the patient bone;
• b) identifying landmarks on bone boundaries in the medical imaging slices;
• c) identifying a hip axis line, the hip axis line being generally collinear with an axis of the patient's femoral head and femoral neck in a preoperative state;
• d) using a computer processor to generate a three dimensional bone model of the patient's acetabular cup;
• e) shape-matching an inner surface of the three dimensional bone model of the patient's acetabular cup relative to the bone axis line;
• f) using data associated with the inner surface of the three dimensional model of the patient's acetabular cup to manufacture the custom acetabular cup positioning guide.

A method of performing an arthroplasty procedure on a hip region of a patient's body, the arthroplasty procedure involving implanting a prosthetic acetabular cup into a patient's acetabular cup, the method comprising:

• preparing the hip region of a patient's body to undergo the arthroplasty procedure, wherein preparing the hip region includes accessing the patient's acetabular cup;
• matingly interdigitating a shape-match hip guide with the patient's acetabular cup, the shape-match hip guide comprising a directional rod and a mating head with a mating surface that is generally a surface negative of a surface contour of the patient's acetabular cup;
• identifying a hip axis line that is generally collinear with a longitudinal axis defined along the directional rod when the mating surface of the mating head matingly interdigitates with the patient's acetabular cup, the hip axis line extending generally collinear with an axis of the patient's femoral head and femoral neck in a preoperative state;
• preparing of the patient's acetabular cup to receive the prosthetic acetabular cup;
• and
• implanting the prosthetic acetabular cup into the patient's acetabular cup along the hip axis line in order to replicate the preoperative state.