The Solution That
Saves Your Bone —
Why the Exeter Stem
Becomes a Lifelong Partner
Hip revision surgery is something no surgeon or patient wants to face — but in an era of longer lifespans, it is a reality that must be prepared for. Here is a detailed look at why the Exeter stem is recognized not just as an implant, but as the optimal solution in revision surgery.
1 Why Revision Surgery Is So Difficult: The Problem of Bone Loss
The two greatest challenges in hip revision surgery are: (1) bone damage caused when removing the existing implant, and (2) how to fill the bone defects — the cavities left behind where bone has already deteriorated and dissolved away.
The most widely used implants today are cementless stems, which work by encouraging bone to grow directly into the rough, porous metal surface — a process called osseointegration. This approach works well for primary surgery, but creates a serious dilemma when revision is needed: the bone has fused into the metal, meaning surgeons must inevitably damage or fracture the surrounding bone to extract the implant.
Case example — a patient who underwent cementless hip replacement. Revision required replacement of the fractured ceramic head and the damaged stem.
| Feature | Cementless Stem | Exeter Stem (Cemented) |
|---|---|---|
| Fixation Method | Bone grows into porous metal | Mechanical taper-lock in bone cement |
| Primary Surgery | ✔ Very effective | ✔ Effective, immediate stability |
| Implant Removal | ✖ Requires breaking away fused bone | ✔ Taper lock released; stem slides out cleanly |
| Bone Preservation | ✖ Additional bone loss on extraction | ✔ Remaining bone stays intact |
| Compatibility with IBG | ✖ Not compatible | ✔ Designed to work with IBG |
2 How the Exeter Stem Is Removed: The Polished Surface and Taper-Lock Release
The Exeter stem is specifically designed so that bone and metal never fuse directly together. Its fixation comes entirely from mechanical force — not biological bonding.
A Mirror-Polished Surface
The surface of the Exeter stem is polished to an exceptionally smooth, mirror-like finish. Rather than bonding directly to bone, the stem is locked firmly inside a mantle of bone cement through a purely mechanical wedging action known as the Taper-Slip principle.
Exeter Stem fixation principle — the Taper-Slip mechanism converts axial load into radial pressure within the cement mantle (B = bone cement)
Clean Extraction Without Bone Damage
Should removal ever become necessary, the surgeon simply releases the mechanical taper-lock using surgical instruments. Because the stem has never fused with bone tissue, the smooth implant slides out from the cement mantle with relative ease — without inflicting additional damage on the patient's remaining bone.
When other implants require breaking away surrounding bone to be removed, the Exeter stem simply unlocks — like withdrawing a key from a lock. The bone is left exactly as it was.
Case Study: Right hip revision surgery. X-rays show before (fractured ceramic head) and after (Exeter stem replacement). The Cement-in-Cement technique preserves the existing cement mantle — replacing only the stem.
3 Overcoming Bone Defects: IBG and the Exeter Stem in Synergy
When revision surgery reveals severe deterioration — the femoral canal essentially hollowed out — the most trusted technique worldwide is Impaction Bone Grafting (IBG). This advanced procedure involves tightly packing finely milled donor bone (allograft) fragments into the empty cavity, then inserting bone cement and the new implant on top.
Cross-section diagram: Exeter Stem (EXETER STEM) surrounded by Impaction Bone Graft filling the bone defect areas, secured within a Bone Cement Layer inside the femur
This technique reaches its full potential when combined with the Exeter stem. Here is why:
With every step the patient takes after surgery, the wedge-shaped Exeter stem micro-settles slightly downward. This axial load is converted into outward, radial pressure — pushing in all directions against the surrounding material.
That radial pressure continuously compresses the packed graft bone fragments outward against the patient's own cortical bone. The graft is not simply sitting there — it is being mechanically loaded with every movement.
Bone responds to mechanical stress by activating regenerative cells — this is Wolff's Law. Thanks to the sustained compression delivered by the Exeter stem, blood vessels begin to grow into the previously lifeless graft fragments. Over time, the donor bone is gradually replaced by the patient's own living bone. What was lost is, in effect, rebuilt.
Bone adapts its structure in response to the mechanical loads placed upon it. Sustained, appropriate pressure activates osteogenic (bone-forming) cells, promoting regeneration and remodeling. The Exeter stem's taper-slip mechanism harnesses this biological principle to turn grafted bone into living bone.
Designed Not Just for Today — But for 10, 20 Years from Now
Most implants focus on a single question: how do we achieve the best fixation right now? The Exeter stem asks a different one: if something goes wrong in ten or twenty years, how do we protect as much of the patient's bone as possible — and give it the best chance of being restored?
The ability to be removed while preserving the remaining bone, and the ability to partner with bone grafting to regenerate what was lost — these biomechanical principles are precisely why the Exeter stem is regarded as a truly irreplaceable, patient-first implant in the field of hip revision surgery.
