Indications
We routinely perform cement within cement revisions in Exeter in situations where the femoral or acetabular cement mantle remains well fixed. If the distal femoral cement mantle is well fixed, in certain cases where the proximal cement mantle is not, we remove the more proximal loose cement and then undertake a cemented revision. This is limited to situations where the proximal loosening is above the level of the lesser trochanter.

Cement within cement revision is indicated for a number of reasons in non-infected cases, including stem removal to allow good acetabular exposure, exchange of a monoblock stem with damage to the head (or modular stem with a damaged or incompatible taper), change of version or length for the treatment of instability or leg length discrepancy, stem fracture or loosening at the prosthesis – cement interface.

Collarless, polished, tapered stems in particular lend themselves to this technique, as they can be easily knocked out of their cement mantle, without damage to the mantle.

The Exeter V40 Short femoral stem.
Although with an Exeter stem it is a simple matter to remove the stem and then reinsert it or a slimmer sized stem into the existing mantle using a cement-within-cement technique, this is not the case when revising other types of femoral component. In addition if a change in version is required, or for the new stem to be inserted more distally, then removal of significant amounts of the existing cement mantle may be required. It may also be necessary to remove cement beyond the tip of the existing prosthesis. This can be difficult, time consuming and in particular carries the risk of femoral perforation or fracture. To avoid this problem, in patients with a short femoral offset we have in the past used a small 35.5mm offset Exeter stem, which is only 125mm long and shorter than most commonly used cemented femoral components. When combined with a +4 head this gives an offset of approximately 38mm. This however is not appropriate in many larger patients. A 44mm offset, short (125mm), slim, femoral stem (25mm shorter than a standard Exeter stem) has therefore been added to the Exeter V40 range specifically as a cement – within – cement revision stem for such cases. It is slim enough to be inserted into the cement mantle cavity of a 44 No 1 stem without the removal of any cement. Depending on the head used an offset between 41mm and 47mm can be achieved.