Partial Knee Replacement in Perth
Robotic-assisted partial knee replacement in Perth by Dr Rhys Clark. Replaces only the damaged compartment of the knee, with a shorter recovery than a total knee replacement.
What’s involved?
Your knee is not one joint so much as three compartments working together — the medial (inside), the lateral (outside), and the patellofemoral (behind the kneecap). Arthritis does not always affect all three.
Partial knee replacement surgery is an option for the treatment of osteoarthritis when the damage is confined to one of them. Unlike a total knee replacement, this surgery involves removing only the damaged sections of bone and cartilage. Only the affected area is resurfaced with metal and a high-density plastic layer, placed to mimic your own joint and cartilage.
Everything else stays: the healthy compartments, and — importantly — the cruciate ligaments in the centre of the knee, which a total replacement usually sacrifices.
“After a partial knee replacement, you can expect to feel less pain and an improved range of motion in the joint. This surgery is all about regaining normal functionality and feel,” says Dr Rhys Clark.
Am I a candidate?
Knee injuries can be just as complex as the joints themselves. For a partial knee replacement to be suitable, two things must be true:
- The arthritic damage is limited to one compartment. If two or more are affected, resurfacing one leaves the others to keep causing pain.
- The surrounding ligaments are healthy and intact, particularly the anterior cruciate. The partial implant relies on your own ligaments for stability — it does not provide its own.
Assessment is done with X-ray and CT or MRI imaging, generally after medication, physiotherapy or injections have stopped controlling the pain.
Not everyone who needs a knee replacement is suitable for a partial one, and the honest position is that most are not — single-compartment disease with good ligaments is a specific picture rather than the usual one. That is not a disappointment so much as an anatomical fact about how arthritis tends to progress.
“I can assess if you’re a suitable candidate for surgery based on X-ray and CT/MRI imaging. If medication, physical therapy, and/or injections have not been effective in alleviating pain, surgery may be an option for you.”
What preserving the knee actually buys you
Where a patient is suitable, the advantages are real:
- A more natural-feeling knee. Keeping the cruciate ligaments preserves much of the joint’s own mechanics and its proprioception — your sense of where the knee is and what it is doing. Patients frequently describe a partial as feeling more like their own knee than a total does.
- A quicker recovery. Less bone is removed and less soft tissue disturbed. Most patients bear weight on the day of surgery and go home within one to three days.
- More bone preserved. This matters for the future: if further surgery is ever needed, there is more to work with.
- A smaller operation. Shorter procedure, less blood loss, typically a smaller incision.
The trade-off worth understanding
A partial knee replacement is not simply a smaller, better version of a total. There is a genuine trade-off, and you should hear it clearly before deciding.
Partial replacements are revised more often than total replacements. The main reason is not that the implant fails, but that arthritis can progress in the compartments that were preserved. The operation treats the damage that exists; it does not stop the rest of the joint ageing.
So the choice is often framed as: a more natural knee with a faster recovery now, against a somewhat higher chance of needing further surgery later. For a younger, active patient with clear single-compartment disease, that trade often favours the partial. For someone with early changes creeping into a second compartment, it usually does not.
If arthritis does progress later, a partial can generally be converted to a total knee replacement. That conversion is usually more straightforward than revising a failed total replacement, precisely because less bone was taken the first time.
A helpful (robotic) hand
Rhys uses robotic assistance in partial knee surgeries. A virtual pre-operation is completed prior to your surgery to ensure you have the best possible outcome. While Rhys is still in control of the procedure, the robotic assists in the bone preparation and placement of the implant.
Accuracy arguably matters more here than in a total replacement. The new component has to sit correctly alongside the parts of your own joint being preserved and work with your own ligaments — there is less room for error when most of the knee is staying put, and a partial that sits slightly wrong can overload the compartments it was meant to protect.
Robotic-assisted knee replacement explains how the CT-based planning works and what the evidence currently supports.
What to expect from surgery
You can usually return home one to three days after your operation. Rehabilitation exercises and further appointments will follow, but the downtime is less than a total knee replacement. Most patients can bear weight on their knee, either with assistance or independently, on the same day as their surgery. Some patients are able to return to their normal activities within three to six weeks.
The week-by-week recovery guide is written around a total knee replacement, but the phases and the principles apply here too, on a shorter timeline — take the pain relief, do the physiotherapy consistently, and treat a swollen day as feedback about pacing rather than a setback.
“Seeing my patients recover after joint replacement surgeries, especially after a short recovery time, is truly rewarding. Knowing that their freedom of movement is no longer limited is a true joy.”
Deciding between partial and total
The decision rests on what the imaging shows, what your ligaments are doing, your age and activity level, and how you weigh a quicker recovery now against the possibility of further surgery later.
It is a conversation rather than a formula, and it is worth arriving with your own questions. If you are still working out whether surgery is the right step at all, Understanding Knee Arthritis covers what arthritis is and what the non-surgical options look like. If cost is a factor, what a knee replacement costs in Australia sets out the public, private and self-funded pathways.
To discuss which operation suits your knee, book a consultation or phone the rooms on (08) 6332 6365.
Am I a candidate for a partial knee replacement?+
Two conditions need to be met: the arthritic damage must be limited to one compartment of the knee, and the surrounding ligaments must be healthy and intact. Dr Clark assesses suitability using X-ray and CT or MRI imaging, generally after medication, physiotherapy or injections have failed to relieve the pain. Roughly speaking, a minority of patients needing a knee replacement are suitable for a partial one.
How long is recovery after a partial knee replacement?+
Recovery is shorter than for a total knee replacement. Most patients bear weight on the knee the same day as surgery, either with assistance or independently, and return home one to three days afterwards. Some patients are back to normal activities within three to six weeks.
Partial or total knee replacement — which is better?+
Neither is better in general; they suit different knees. A partial replacement preserves more of your own knee, including the cruciate ligaments, and usually feels more natural with a quicker recovery — but it is only suitable when a single compartment is damaged, and it carries a higher likelihood of needing further surgery later. A total knee replacement addresses the whole joint surface and is less likely to need revising.
Is a partial knee replacement done robotically?+
Yes. Dr Clark uses robotic assistance for partial knee replacement. A virtual pre-operation is completed beforehand from a CT scan, and the robot assists with bone preparation and implant placement while the surgeon remains in control of the procedure. Accuracy arguably matters more in a partial replacement than a total one, because the implant has to work alongside the parts of your own joint being preserved.
Does a partial knee replacement feel more natural than a total?+
Many patients report that it does. Because the cruciate ligaments and the undamaged compartments are kept, the knee retains more of its own mechanics and proprioception — the sense of where the joint is in space. This is one of the main arguments for a partial where a patient is suitable.
What happens if arthritis develops in the rest of the knee later?+
It can, and it is the commonest reason a partial replacement needs further surgery. If arthritis progresses into a compartment that was preserved, the partial can usually be converted to a total knee replacement. That conversion is generally more straightforward than revising a failed total replacement, because less bone was removed originally.
How long does a partial knee replacement last?+
Most last many years, but as a group partial replacements are revised more often than total replacements — largely because arthritis can progress in the compartments left behind. That trade-off is worth discussing openly: a partial offers a more natural knee and quicker recovery now, against a somewhat higher chance of further surgery later.