Bone preserving anatomic hip arthroplasty system

A hip prosthesis system, comprising:

• a) a medullary nail for insertion into a femoral canal of the femur, the nail having a proximal end, a distal end, a length between the proximal and distal ends, a longitudinal axis extending through the proximal and distal ends, a neck opening having a central axis extending at a neck angle relative to the longitudinal axis;
• b) a neck component having a body and a seat,
• the body of the neck component having a width and a height greater than the width,
• the body of the neck component supportable in the neck opening at the neck angle and longitudinally displaceable relative to the neck opening at the neck angle;
• c) a locking assembly adapted to secure the neck component in position relative to the medullary nail;
• and
• d) a bone anchor having a central opening, a front face, a rear face, a plurality of screw holes extending through the front and rear faces, and at least one locking screw extending into the central opening, the central opening sized and shaped to receive the body of the neck beam,
• wherein when the body of the neck component is positionable through the central opening of the bone anchor and the locking screw is tightened, the bone anchor is secured relative to the neck component.

A method of setting a position of a prosthetic femoral head during a hip arthroplasty, comprising:

• a) cutting the femoral head off the femoral neck to define a flat bone surface;
• b) providing a bone anchor having a central opening extending between the front and rear faces;
• c) securing the rear face of the bone anchor to the flat bone surface;
• d) providing a neck component having a head seat and a body;
• e) positioning the body of the neck component within the central opening of the bone anchor;
• f) locking the position of the neck component relative to the bone anchor;
• and
• g) implanting the prosthetic femoral head on the head seat.

A method of setting a position of a prosthetic femoral head during a hip arthroplasty, comprising:

• a) implanting a nail within a medullary canal of a femur, the nail having an opening;
• b) inserting a neck component through the opening in the nail;
• c) providing a femoral head trial onto an end of the neck component, the femoral head trial having an opening axial with the neck component and communicating with the neck component;
• d) measuring or testing the fit of the femoral head trial;
• e) inserting an instrument through the opening in the femoral head trial, engaging the neck component, and longitudinally displacing the neck component relative to the nail with the instrument;
• f) locking the position of the neck component relative to the nail;
• and
• g) replacing the femoral head trial with a prosthetic femoral head.

A method of setting a position of a prosthetic femoral head during a hip arthroplasty, comprising:

• a) implanting a nail within a medullary canal of a femur, the nail having an opening;
• b) inserting a neck component through the opening in the nail;
• c) inserting a prosthetic femoral head onto the neck component;
• e) positioning the prosthetic femoral head into a corresponding hip joint component in a pelvis, the femoral head rotatable relative to the corresponding hip joint component;
• f) engaging the neck component with an instrument, and longitudinally displacing the neck component relative to the nail with the instrument;
• and
• g) locking the position of the neck component relative to the nail.

A method of implanting a total hip prosthesis, comprising

• a) implanting a medullary nail into a femoral canal of a femur, the nail having a proximal end, a distal end, a longitudinal axis extending through the proximal and distal ends, and a neck hole having a central axis extending at an angle between 110° to 140° relative to the longitudinal axis;
• b) cutting a femoral head off a femoral neck of the femur to form a cut-off femoral neck;
• c) inserting a neck component having a head seat and a body, the body passing through the neck hole of the medullary nail;
• d) implanting an acetabular cup assembly;
• e) placing a femoral head on the neck seat of the neck component;
• and
• f) inserting the femoral head into the acetabular cup assembly.