About Dr. Darshan Devani
Dr. Darshan Devani is a Joint Replacement Surgeon in Surat, specializing in primary and revision knee and hip replacement, arthroplasty, and robotic-assisted joint replacement. He has over a decade of experience in joint replacement and has received fellowship training in hip and knee arthroplasty in Mumbai and adult reconstruction surgery in Munich, Germany.
The first thing to get straight is that the robot doesn’t perform your knee replacement. Your surgeon does.
What the machine provides is guidance — a 3D plan built from your own anatomy, and an arm that physically resists the saw if the surgeon’s hand drifts outside that plan. It’s closer to a very sophisticated set of surgical instruments than to an autonomous operator. Some patients arrive at the consultation expecting a machine to do the cutting while the surgeon watches. That’s not what happens, and it’s worth knowing before you weigh the decision.
So what is the actual benefit? It’s real, but narrower and more specific than most hospital marketing pages suggest. Here’s a straight account of where robotic assistance in total knee replacement (TKA) helps, where the evidence is thinner, and what it doesn’t change.
How Robotic-Assisted Knee Replacement Works, Step by Step
The workflow varies by system, but the logic is broadly shared.
1. Imaging and planning. With CT-based systems, you have a scan before surgery. The software converts it into a three-dimensional model of your femur and tibia — your actual bone shapes, your actual deformity. Imageless systems skip the scan and build the model intraoperatively by registering anatomical landmarks instead. Both approaches end up in the same place: a plan with specific angles, resection depths, and implant sizes chosen for your knee rather than for an average knee.
2. Registration. In the operating room, the surgeon confirms that the digital model matches your real anatomy, mapping landmarks and surface points. Accuracy here determines everything downstream.
3. Bone preparation. This is the step patients find most surprising. The surgeon still holds the saw. A robotic arm constrains its movement within a defined boundary — haptic feedback that makes it physically difficult to cut outside the planned plane. You can think of it as a very precise guide rail that only exists in software.
4. Balance assessment. Several systems let the surgeon check ligament tension and joint balance before committing to final implants, then adjust the plan if the soft tissues tell a different story than expected.
5. Verification. The final position of the components is measured against the plan, in the room, before closing. No waiting for a post-operative X-ray to find out whether things landed where they should.
Different platforms sit at different points on the spectrum. Some are semi-active haptic systems, some are imageless navigation-linked robots, and each has trade-offs in scan requirements, workflow, and cost. For a patient, the honest summary is that the platform matters less than the surgeon’s experience with it.
Where the Evidence Is Strongest: Positioning and Alignment
This is the least contested benefit, and it’s not a small one.
Conventional knee replacement relies on jigs and rods aligned to anatomical landmarks, combined with the surgeon’s judgement. It works well in experienced hands. But it produces outliers — cases where final alignment drifts meaningfully from the target — more often than robotic assistance does. Multiple systematic reviews and meta-analyses have consistently found that robotic-assisted TKA achieves more accurate component positioning and better mechanical alignment, with fewer cases falling outside the intended range.
Why does that matter? Because malalignment and poorly positioned components are associated with earlier wear, instability, and revision. Precision isn’t cosmetic.
One caution: achieving a specific alignment target is not the same as achieving a better-functioning knee. That gap between “the numbers are better” and “the patient feels better” is where most of the genuine debate lives.
Where the Evidence Is More Modest: Function, Pain, and Recovery
Here the picture gets muddier, and anyone telling you otherwise is overselling.
Randomised trials and meta-analyses comparing robotic-assisted with conventional TKA generally report either comparable or modestly improved early functional outcomes. Some studies show better early pain scores, quicker achievement of range of motion, or shorter hospital stays. Others find no significant difference in patient-reported outcomes at one year.
A prospective cohort study following patients to five years reported comparable functional outcomes between the two approaches, but higher Forgotten Joint Scores in the robotic-assisted group — meaning patients were less conscious of their knee during daily life. That’s a meaningful patient-centred measure, but it’s one study, not settled science.
Registry data has been similarly mixed. Some analyses suggest lower early revision rates with robotic assistance; others find comparable survivorship and safety. What most of the long-term data agrees on is that revision rates are low for both techniques in appropriately selected patients.
If you want the honest one-sentence version: robotic assistance reliably improves how well the surgery is executed, and shows a modest, inconsistent advantage in how patients feel afterward.
The Alignment Debate the Robot Makes Possible
Something interesting has happened alongside the technology.
For decades, the goal in knee replacement was a standard mechanical alignment — everyone’s leg brought to roughly the same neutral position. That’s an average, and averages don’t fit everyone. A growing body of work suggests that restoring a patient’s own pre-arthritic alignment, or an individualised target somewhere between their native alignment and neutral, may produce better function in some people.
Executing a personalised alignment plan requires precision that manual techniques struggle to deliver consistently. Robotic systems make it practical. So in a sense, the robot’s most interesting contribution isn’t that it hits the target better — it’s that it lets surgeons aim at a different target altogether.
That’s an evolving area, not a settled one. But it’s the direction a lot of the field is moving.
Complex Cases: Where It Helps Most
The patients who seem to benefit most clearly are those whose anatomy makes standard instrumentation unreliable:
- Severe deformity, either bow-legged or knock-kneed beyond the usual range
- Extra-articular deformity — the crookedness is in the femur or tibia shaft, not just the joint
- Retained hardware from a previous fracture or osteotomy
- Post-traumatic arthritis with distorted anatomy
- Some revision surgeries, where normal landmarks are gone
In these situations, conventional jigs may not seat properly or may reference landmarks that no longer exist. A system that plans from a 3D model of the actual bone can navigate around those problems. Several recent reviews point specifically to complex primary and revision cases as the setting with the clearest technical advantage.
Also reasonable candidates: younger, higher-demand patients where durability matters more, and patients with significant bone quality concerns who need precise cementless component seating.
What Robotic Surgery Doesn’t Fix
This section matters as much as the ones above.
It doesn’t replace rehabilitation. The knee still needs to be moved, strengthened, and progressively loaded afterward. Patients who do their physiotherapy consistently do better than patients who don’t, regardless of which technique was used.
It doesn’t make the implant last forever. Implant choice, your bone quality, your activity level, your weight, and your overall health all influence longevity at least as much as surgical technique does.
It doesn’t guarantee a smaller incision or less pain. Soft tissue handling is still the surgeon’s job. Some systems and approaches are more tissue-sparing than others, but “robotic” on its own doesn’t promise that.
It adds cost. The technology carries additional expense — the CT scan where required, the disposable instrumentation, the capital cost of the system. Coverage and out-of-pocket impact vary considerably by country, hospital, and insurer. Ask specifically.
It has a learning curve. Studies on operative time suggest surgeons need on the order of 15 to 20 cases to reach proficiency, and roughly twice that to match the speed of their manual technique. An experienced robotic surgeon is not the same thing as a surgeon who has just bought the machine.
It uses radiation if CT-based. A planning scan involves a modest radiation dose. Imageless systems avoid it. Not a major factor for most patients, but worth knowing.
Questions Worth Asking Your Surgeon
Bring these to the consultation. The answers will tell you more than any brochure.
- How many robotic knee replacements have you personally performed?
- Which system do you use, and why did you choose it?
- Do you use CT-based planning or imageless registration?
- What alignment philosophy do you follow — mechanical, kinematic, or individualised?
- Would you recommend robotic assistance for my specific knee, and why or why not?
- What does it add to the cost, and is it covered?
- How would my recovery differ either way?
A surgeon who says “you’d do well with either approach, here’s why I’d lean this way for your knee” is giving you a more trustworthy answer than one who says robotics is essential for everyone.
Realistic Recovery Expectations
Robotic assistance doesn’t rewrite the biology of healing. Most patients can expect something like this:
- Day of surgery to day 2: walking with assistance, beginning range-of-motion work
- Weeks 1–3: increasing walking distance, managing swelling, physiotherapy underway
- Weeks 4–6: driving typically resumes, return to desk-based work for many
- Months 3–6: most daily function restored, strength still building
- Year 1 and beyond: continued improvement in strength and confidence for some patients
Some robotic-assisted patients go home earlier than they would have otherwise. That’s a genuine potential benefit — and also the kind of thing that depends more on your overall health, home support, and hospital protocol than on the robot.
So, Does It Help?
Yes, in specific, measurable ways. It helps surgeons place components more accurately and hit alignment targets more consistently, which is directly relevant to how long a knee replacement lasts. It helps most in knees that are hardest to instrument conventionally. And it makes individualised alignment strategies practical.
It helps less than the marketing implies at the level of “your knee will feel better because of the robot.” On that measure, the honest evidence is modest and inconsistent, and other factors — surgeon skill, implant selection, soft tissue handling, your rehabilitation — carry at least as much weight.
If you’re offered robotic-assisted surgery by an experienced surgeon at a hospital that does a high volume of knee replacements, that’s a good position to be in. If the same surgeon offers conventional surgery, that’s also a good position. The technique is one variable. It isn’t the only one.
Dr. Darshan Devani is a Joint Replacement Surgeon in Surat with a focus on knee and hip replacement, robotic knee replacement, primary and revision arthroplasty, and adult reconstruction surgery. He completed his D.N.B. in Orthopaedics from Central Railway HQ Hospital, Mumbai, followed by fellowship training in Hip & Knee Arthroplasty in Mumbai and Adult Reconstruction Surgery in Munich, Germany. Shalby Multispeciality Hospital
Dr. Darshan Devani
Joint Replacement Surgeon
Knee & Hip Care | Robotic Joint Replacement
Surat, Gujarat
FAQ
Is robotic knee replacement safer than conventional surgery? Safety profiles appear broadly comparable across studies, with low complication rates in both. Some analyses report shorter hospital stays or fewer soft tissue releases with robotic assistance; others find no significant difference. There’s no strong evidence that robotic surgery is dramatically safer.
Does it mean less pain afterward? Some patients report lower early pain scores. The evidence isn’t consistent enough to promise that. Most of the pain after knee replacement comes from soft tissue trauma and bone cutting, which happens either way.
Will my knee last longer? It may, indirectly. Better alignment and component positioning are associated with improved implant longevity, which is the strongest theoretical argument for the technology. But direct long-term registry evidence comparing survivorship is still mixed and maturing. If durability is your main concern, ask your surgeon about alignment targets and implant choice as well.
What if I have severe deformity? This is arguably where robotic assistance offers the clearest advantage. Discuss it specifically with your surgeon — severe deformity, prior osteotomy, or retained hardware are the scenarios where 3D planning and haptic guidance add the most value.
Do I still need physiotherapy? Yes. Without question. No surgical technique substitutes for rehabilitation.
Is it available everywhere? No. Availability depends on your hospital’s investment in the technology and your surgeon’s training. In many public health systems it’s offered selectively, often prioritised for complex cases.
Consult Dr. Darshan Devani
If you are considering robotic knee replacement, consult Dr. Darshan Devani, Joint Replacement Surgeon in Surat, to understand whether robotic-assisted knee replacement is appropriate for your individual knee condition.
Book an Appointment
