The question comes up in almost every knee replacement consultation: Is robotic surgery better than the traditional approach?
It’s a fair question. Robotic-assisted joint replacement has been marketed aggressively over the past decade, and patients naturally want to know what they’re actually getting when a hospital or surgeon promotes “robotic surgery.” What does the technology do? What doesn’t it do? Does it change the recovery? Does it produce better long-term outcomes? Is it worth choosing a robotic surgeon over a traditional one?
The honest answer is that robotic-assisted knee replacement changes some things meaningfully, some things modestly, and some things not at all. Patients considering knee replacement deserve a clear, unhyped explanation of what the technology actually does — and what it doesn’t.
At HSS Long Island in Uniondale, Dr. Tony Shen performs both robotic-assisted total and partial knee replacement. This is what patients should understand about the differences between the two approaches — and what actually matters for their care.
Serving Long Island patients from HSS Long Island in Uniondale — minutes from Garden City, Hempstead, Westbury, and East Meadow—call (212) 224-7988 to schedule your consultation.
What “Robotic Knee Replacement” Actually Means
The term “robotic surgery” can be misleading. When patients hear it, some imagine a robot operating autonomously. That’s not what robotic-assisted knee replacement is.
Robotic-assisted knee replacement is a precision tool the surgeon uses to plan and execute the procedure with greater accuracy than traditional techniques allow. The surgeon remains in control throughout. The system provides constraints, measurements, and real-time feedback that help the surgeon match the plan to the patient’s specific anatomy.
Here’s what typically happens in a robotic-assisted knee replacement:
- Preoperative planning — Advanced imaging of the patient’s knee is used to build a three-dimensional model of their specific anatomy. The surgeon plans implant size, position, and alignment on that model before the operation.
- Intraoperative registration — During surgery, the robotic system registers the patient’s actual knee against the preoperative plan and tracks how the joint moves through its range of motion.
- Plan adjustment — If the patient’s knee behaves differently than the imaging predicted (which happens often), the surgeon adjusts the plan in real time before anything permanent happens.
- Guided bone preparation — The robotic arm assists with bone cuts within precisely defined boundaries, helping ensure the surgical execution matches the plan.
The surgeon operates. The technology helps constrain error rather than replacing surgical judgment.
Traditional knee replacement, in contrast, relies on standard cutting guides, visual assessment, and the surgeon’s experience to determine implant size, position, and alignment — often making key decisions during the operation itself rather than before it.
What Actually Changes for the Patient (And What Doesn’t)
Here’s where the honest conversation matters most. Robotic-assisted knee replacement is often marketed as if it revolutionizes patient care. The reality is more nuanced.
What Meaningfully Changes
Precision of implant positioning. Multiple studies have demonstrated that robotic-assisted knee replacement produces more consistent implant alignment than traditional techniques. In traditional knee replacement, alignment can vary based on the surgeon’s visual assessment. Robotic assistance measurably tightens that variability.
Preservation of healthy tissue. Because the plan is precise before the first cut, less healthy bone and soft tissue are disturbed during the procedure. The robotic system’s guidance helps ensure cuts stay within the planned boundaries.
Soft-tissue balance. How the ligaments around the knee are balanced significantly affects how the replaced knee feels afterward. Robotic assistance provides real-time feedback about ligament tension and joint gaps, helping the surgeon fine-tune the balance more precisely than visual assessment alone allows.
Ability to handle complex anatomy. Patients with unusual anatomy, prior fractures, deformity, or previous surgeries benefit particularly from the ability to plan and adjust in three dimensions. Traditional techniques can struggle with atypical presentations that robotic planning addresses more consistently.
Suitability for partial knee replacement. For patients who are candidates for partial knee replacement (where only one compartment of the knee is resurfaced), the precision of robotic assistance is arguably even more important than for total replacement. Partial replacement demands exact alignment because the new component must work in harmony with the untouched parts of the joint.
What Changes Modestly
Early functional recovery. Some studies suggest slightly faster early functional recovery with robotic-assisted knee replacement—walking with less assistance and achieving early range-of-motion targets sooner. The magnitude of this effect varies by study and by patient.
Length of hospital stay. In some cases, patients with robotic-assisted procedures may go home slightly sooner, though this depends heavily on individual health factors rather than the technology itself.
Pain in the first few weeks. Some patients report slightly less post-operative pain with robotic assistance, though this varies significantly and isn’t consistently demonstrated across all studies.
What the Research Actually Shows
The research on robotic-assisted knee replacement continues to evolve. Here’s what current evidence suggests:
Alignment and positioning: Multiple studies consistently show that robotic-assisted knee replacement produces more accurate and consistent implant alignment than traditional techniques.
Short-term patient outcomes: Early data suggests some benefit in early functional recovery, though the magnitude is modest and doesn’t apply to every patient.
Long-term outcomes: This is where the picture is less clear. Whether the improved precision translates to better function 10, 15, and 20 years after surgery is still being studied. Early signs are encouraging, but definitive long-term data is still being collected.
Patient satisfaction: Studies of patient-reported outcomes have shown modest improvements with robotic assistance, though satisfaction rates for both approaches are generally high when performed by experienced surgeons.
The honest summary: robotic assistance produces measurably more precise surgery, and modest improvements in patient experience and early recovery. Whether that translates to meaningfully better long-term outcomes remains an active area of research.
Who Benefits Most From Robotic-Assisted Knee Replacement?
While robotic assistance is beneficial across a range of patients, certain groups may benefit particularly:
Younger, more active patients. For patients in their 40s, 50s, and early 60s who need the implant to last decades and perform under high functional demand, the additional precision matters more. Small alignment errors that a 75-year-old low-demand patient might never notice can create problems for a 55-year-old active patient over 20-30 years of use.
Partial knee replacement candidates. As discussed above, partial knee replacement demands more precision than total replacement. The technology’s benefits are particularly valuable here.
Patients with complex anatomy. Prior fractures, unusual bone geometry, or previous surgeries create alignment challenges that benefit from three-dimensional planning.
Patients with high functional expectations. Athletes, active retirees, and patients wanting to return to demanding recreational activities may benefit from the additional precision that supports better long-term function.
Patients with previous joint replacements. Those needing revision surgery or replacement of a second joint often benefit from planning that accounts for existing hardware or the outcome of prior procedures.
What Actually Determines Your Outcome
Here’s the honest surgeon’s perspective: the specific technology used in your knee replacement is one factor among many that determines your outcome. The others are often more important.
Your surgeon’s experience. How many knee replacements they perform annually. How they think about your specific case. Their track record with patients similar to you.
Whether you’re actually a candidate for the procedure; not everyone with knee pain needs replacement. A good surgeon will tell you honestly whether surgery is the right answer for you now.
Whether total or partial replacement is the right choice. For some patients, partial replacement is a better answer. A surgeon comfortable with both approaches can offer the right procedure—not just the one they know how to do.
Your health going into surgery. Cardiovascular health, weight, muscle strength, and other health factors all influence how well you recover.
Your commitment to rehabilitation. The work you do in the first six weeks after surgery has an outsized effect on the final result.
The care you receive at every stage. Not just the surgery itself, but preoperative planning, anesthesia, post-op pain management, and rehabilitation.
Focusing exclusively on whether the surgery is robotic or traditional misses the bigger picture. The right question is whether the entire care team — surgeon, hospital, rehabilitation team — will produce the best outcome for your specific situation.
The Practical Reality: What This Means for Long Island Patients
For Long Island patients considering knee replacement, here’s the practical takeaway:
If your surgeon offers robotic-assisted knee replacement, ask what specific benefits they believe it provides for your case. A confident surgeon should be able to explain clearly why the approach is right for your situation—not just that they use the latest technology.
If your surgeon uses traditional techniques, that doesn’t necessarily mean lower quality care. Experienced surgeons using traditional techniques produce excellent outcomes. The technology is one tool, not the whole picture.
Ask about outcomes, not just technology. How often do their patients require additional surgery? What are their infection rates? What do their patient satisfaction scores look like?
Ask about the entire care experience. Where will your surgery be performed? Who provides your rehabilitation? What’s the post-operative pain management approach?
Ask about candidacy. Are you a candidate for partial knee replacement instead of total? Are there non-surgical options you should try first?
The best consultation should leave you understanding not just what surgery is available, but whether you’re the right candidate—and what specifically about your case makes their recommended approach the best fit.
What Dr. Shen’s Approach Includes
At HSS Long Island in Uniondale, Dr. Tony Shen offers:
Fellowship-trained expertise in joint replacement. Dr. Shen is board-certified by the American Board of Orthopedic Surgery and completed both his residency and his Adult Reconstruction and Joint Replacement fellowship at Hospital for Special Surgery — one of the country’s premier orthopedic institutions.
HSS-level care close to home. Long Island patients receive the same evidence-based approach used at HSS’s Manhattan location without commuting into New York City for every visit.
Both robotic and traditional expertise. Dr. Shen is trained in both approaches and can recommend the appropriate technique for each patient’s specific situation.
Focus on personalized medicine. Dr. Shen’s published research covers personalized medicine in joint replacement, rapid recovery approaches, and robotic surgical precision — meaning your care benefits from ongoing engagement with the latest evidence.
Both total and partial knee replacement. For patients who are candidates for partial knee replacement, Dr. Shen offers this alternative rather than defaulting to total replacement.
Honest consultations. You should leave your consultation knowing whether you’re a surgical candidate, what non-surgical options remain, what to expect from the procedure, and what your realistic outcomes are—with real numbers for your specific case.
Frequently Asked Questions
Is robotic knee replacement better than traditional knee replacement?
Robotic-assisted knee replacement produces measurably more accurate implant positioning and alignment than traditional techniques. Whether this translates to significantly better long-term outcomes remains under study. For patients with certain characteristics — including younger age, higher activity levels, and complex anatomy — the precision benefits are more meaningful.
Robotic-assisted knee replacement produces measurably more accurate implant positioning and alignment than traditional techniques. Whether this translates to significantly better long-term outcomes remains under study. For patients with certain characteristics — including younger age, higher activity levels, and complex anatomy — the precision benefits are more meaningful.
Does robotic knee replacement mean a robot performs the surgery?
No. Robotic-assisted knee replacement is a precision tool the surgeon uses. The surgeon plans the procedure, controls the robotic system, and performs the operation. The technology helps constrain error and improve accuracy; it doesn’t replace surgical judgment.
No. Robotic-assisted knee replacement is a precision tool the surgeon uses. The surgeon plans the procedure, controls the robotic system, and performs the operation. The technology helps constrain error and improve accuracy; it doesn’t replace surgical judgment.
Does robotic knee replacement have a shorter recovery?
Some studies suggest slightly faster early functional recovery, but the difference is modest and varies significantly between patients. Full recovery still takes months regardless of the technique, and physical therapy is equally important with either approach.
Some studies suggest slightly faster early functional recovery, but the difference is modest and varies significantly between patients. Full recovery still takes months regardless of the technique, and physical therapy is equally important with either approach.
Is robotic knee replacement more expensive?
The technology and associated care can be more expensive at some facilities, though this varies. Insurance coverage for robotic-assisted knee replacement is widespread, but details vary by plan.
The technology and associated care can be more expensive at some facilities, though this varies. Insurance coverage for robotic-assisted knee replacement is widespread, but details vary by plan.
Does robotic surgery mean less pain after surgery?
Some patients report less post-operative pain with robotic-assisted procedures, but the difference is inconsistent across studies. Pain management after knee replacement depends on many factors beyond just the surgical technique.
Some patients report less post-operative pain with robotic-assisted procedures, but the difference is inconsistent across studies. Pain management after knee replacement depends on many factors beyond just the surgical technique.
Can any surgeon do robotic knee replacement?
No. Surgeons need specific training and certification to perform robotic-assisted procedures. Choosing a surgeon with fellowship training in joint replacement (like Dr. Shen’s HSS fellowship) is often more important than simply choosing one with robotic training.
No. Surgeons need specific training and certification to perform robotic-assisted procedures. Choosing a surgeon with fellowship training in joint replacement (like Dr. Shen’s HSS fellowship) is often more important than simply choosing one with robotic training.
Should I choose a surgeon who does robotic surgery over one who doesn’t?
Not necessarily. Surgeon experience, judgment, and track record matter more than the specific technology used. An experienced surgeon using traditional techniques often produces better outcomes than an inexperienced surgeon using robotic assistance.
Not necessarily. Surgeon experience, judgment, and track record matter more than the specific technology used. An experienced surgeon using traditional techniques often produces better outcomes than an inexperienced surgeon using robotic assistance.
Is partial knee replacement better with robotic assistance?
For eligible patients, partial knee replacement benefits greatly from robotic precision. Partial replacement demands exact alignment because the new component must work with the knee’s natural, healthy parts.
For eligible patients, partial knee replacement benefits greatly from robotic precision. Partial replacement demands exact alignment because the new component must work with the knee’s natural, healthy parts.
How do I know if I’m a candidate for robotic knee replacement?
If you’re a candidate for knee replacement, you’re generally a candidate for the robotic approach. The question is whether you’re actually a candidate for knee replacement in the first place — and whether total or partial replacement is right for you. A good consultation should tell you honestly.
If you’re a candidate for knee replacement, you’re generally a candidate for the robotic approach. The question is whether you’re actually a candidate for knee replacement in the first place — and whether total or partial replacement is right for you. A good consultation should tell you honestly.
How long does a robotic knee replacement last?
Modern knee replacements — whether performed with robotic or traditional techniques — typically last 15-25 years or longer. Whether the precision improvements of robotic assistance extend implant lifespan meaningfully is still being studied.
Modern knee replacements — whether performed with robotic or traditional techniques — typically last 15-25 years or longer. Whether the precision improvements of robotic assistance extend implant lifespan meaningfully is still being studied.
Schedule a Consultation With Dr. Tony Shen
If you’re considering knee replacement — or trying to decide whether you’re ready — Dr. Tony Shen and his team can help you understand your options honestly.
Dr. Tony Shen, MD, is a fellowship-trained orthopedic surgeon at Hospital for Special Surgery specializing in hip and knee reconstruction, including robotic-assisted total and partial knee replacement. Trained at Harvard University, Washington University School of Medicine, and Hospital for Special Surgery, he brings HSS-level joint replacement expertise to Long Island patients at HSS Long Island in Uniondale. Call (212) 224-7988 to schedule your consultation.
