Operative technique
Step 1 Confirm that a cemented hemiarthroplasty is indicated.
An X-ray template of the ETS stem is provided.
This should be used as a guide with the pre-operative X-ray, comparing both affected and contra lateral hips.
Particular care should be made regarding the likely stem insertion depth in relation to the tip of the greater trochanter.
Note: The centre of the femoral head is normally 2-3mm deeper than the tip of the greater trochanter. The mark on the rasp instrument is at the level of the centre of rotation of the prosthetic head.
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Fig 1 X-ray with overlying template
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Step 2 The patient is positioned and prepared on the operating table in the usual manner. Expose the hip joint using your preferred surgical approach for hemiarthroplasty. Note: The authors recommend an anterolateral approach1 in the majority of cases.
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Fig 2. Patient position.
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Step 3 Following exposure of the hip, cut the femoral neck 1 to 1.5cm above the lesser trochanter. The exact level and orientation of neck cut is not critical as the ETS stem has no collar or other features which will affect the osteotomy line. Fig 3
Remove and measure the femoral head or alternatively use an appropriate instrument to estimate the size of the acetabulum. Fig 4 
Fig 3. Cut neck at desired level
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Fig4. Measure head size.
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Step 4 Ensuring that the gluteus medius tendon is retracted and protected, a box chisel is used to open the proximal femur. This should be positioned laterally and posteriorly to gain exposure in line with the femoral canal. Fig 5
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Fig 5. Box chisel positioned laterally and posteriorly
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Step 5 The taper pin reamer is used to open up the femoral canal.
Ensure that it is directed in a neutral position down the axis of the femur.
Aim at the centre of the patella if an anterior approach is being used or, alternatively the popliteal fossa if a posterior approach is employed. Fig 6
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Step 6 Prepare the proximal femur with the femoral rasp. The rasp should be inserted until the mark on the handle is opposite to or just below the level of the tip of the greater trochanter. Fig 7
Note: If the contra lateral hip is normal then insert the rasp to the depth of the tip of the greater trochanter. If the hip is in varus then this may need to be deeper – as determined from the pre-operative X-ray templating.
The rasp should be inserted with the required amount of anteversion; typically this is between 0° and 20° depending on the preferred approach.
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Fig 7. Taper pin reamer used to open femoral canal
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Step 7 Using the rasp as a guide, mark the cut surface of the femoral neck at the desired stem insertion depth, using methylene blue or the tip of a diathermy forceps. Likewise the shoulder of the rasp can also be used as a reference. Fig 8
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Fig 8. Mark femoral neck
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Step 8 Proceed with the preferred method of cementing technique. (Modern cementing techniques are recommended, including the use of a distal cement plug, thorough lavage and drying of the canal and retrograde filling with a cement gun).
Prior to insertion of the stem, the cement centraliser should be placed on the distal stem tip. Fig 9
Both a winged and wingless cement centraliser are included with the prosthesis. For a canal size of 10mm or less, the wingless centraliser should be used.
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Fig 9. Stem with centraliser on.
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Step 9 The stem is inserted to the previously determined level (Step 7), using the stem insertion instrument. Place a thumb over the cement in the calcar, to maintain pressure during stem insertion.
The stem should be inserted with the chosen degree of anteversion as previously determined in Step 6.
Care should be taken to ensure that the soft tissues are retracted and do not push on the head of the prosthesis, thus altering the degree of anteversion. It is essential that the stem is held in position until the cement has fully polymerised in order to prevent movement of the stem within the cement mantle. 
Stem Inserter
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Stem in situ.
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Step 10 Reduce the hip, and after confirming stability and a concentric reduction, close the wound in a routine fashion.
Revision: In the event of revision of the hemiarthroplasty to a total hip replacement in the future, the ETS stem can be tapped back out of the cement mantle after clearing any cement or fibrous tissue from over the shoulder of the prosthesis. After acetabular preparation a size 0 (44mm or 37.5mm offset) Exeter™ stem can easily be recemented into the old cement mantle.
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