1. Preoperative Templating
Preoperative templating is crucial to the success of this procedure. The height of the prosthesis is determined to restore equal leg lengths. Measurement is made from the tip of the greater trochanter. Note the center of the femoral head has been moved 4 mm superior to make up for a 4 mm discrepancy in leg length.
Tip: A high offset component was selected to restore anatomic offset in this varus hip. A standard offset is typically used in valgus hips.

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2. Incision Planning
A line is drawn down the center of the femoral shaft. Beginning 4 cm distal to the proximal tip of the greater trochanter, a line is drawn 3 cm posteriorly. A 6 cm line is drawn to intersect the femoral shaft creating the hypotenuse of a 30°-60°-90° triangle. A 10 cm incision is then drawn from the posterior corner of the triangle.
Tip: The Incision finder can be used to quickly determine incision location. Find tip of the greater trochanter with spinal needle through hole in finder. Align line distal to hole with the neutral axis of the femur. Use 10 cm line for incision.
Tip: Obese patients: The tip of the greater trochanter may be identified with a spinal needle. Moving the incision 1-1.5 cm distally will aid in acetabulum insertion.

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3. Gluteus Maximus Fascia Dissection
The gluteus maximus fascia is then identified with sharp dissection.
Tip: The distal aspect of the incision in the gluteus maximus should encounter posterior femur.

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4. Charnley Retraction
A Charnley retractor is used to visualize the external rotators. A Cobb elevator is placed superior to the piriformis and directly on bone under the gluteus medius and minimus.
Tip: The bursal tissue should be taken down carefully to control bleeding. Bleeding will make visualization difficult.

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5. Superior Capsule
A knife may be used to divide the superior capsule in tight hips. However, often it can be left intact.
Tip: The Cobb elevator is on top of the superior capsule. The knife should follow the elevator to its distal end.
Alternative: Can use a bovie and make a hockey stick capsule incision.

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6. External Rotators
The external rotators and capsule are taken down together to expose the femoral neck and head. The Cobb elevator is still in place. It is again important to control bleeding.
Tip: It is possible to perform the approach without detaching the piriformis tendon. Simply make the capsular incision just distal to the piriformis tendon.

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7. Dislocation
The hip is dislocated with internal rotation of the femur. A cobra retractor is placed under the inferior neck of the femur in preparation for the neck cut.
Tip: If necessary, the lesser trochanter is easily identified with a Hohmann retractor

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8. Neck Osteotomy
A transverse neck cut is made. The cobra helps protect the sciatic nerve.
Tip: If a collarless implant is selected, the transverse neck cut can be made arbitrarily approximately 1 finger breadth below the femoral head. A collared implant can be prepared for by using traditional landmarks.

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9. Anterior Capsule
An incision is made in the anterior capsule while an assistant elevates the trochanter with a bone hook. This is in preparation for a retractor over the anterior wall at the 8:00 position.
Tip: This is not a release of the anterior capsule. The incision only needs to be as long as the width of the anterior retractor.
Optional: A sharp pointed Hohmann retractor can be driven into the anterior column at 10:00, just proximal to the acetabular rim. This will prevent any potential trauma to anterior/neurovascular structures and aid in reamer insertion.