Robotic-Assisted Joint Replacement

A more precise way to plan and perform hip and knee replacement — used when it helps, explained honestly when the evidence is mixed.

What is robotic-assisted joint replacement?

Robotic-assisted joint replacement uses the Stryker Mako system — computer-guided technology to help your surgeon plan your operation in three dimensions and carry out that plan with a high degree of precision. A CT scan of your joint is used to build a detailed 3D model, and your surgeon uses that model to plan the exact size, position, and alignment of your implant — before the first incision is made.

One important clarification: the robot does not perform the surgery. Dr. Sloan performs every step of the operation. The robotic system is a tool — like a highly precise instrument — that helps execute the surgical plan and provides real-time feedback during the procedure.

How it works

1. Personalized 3D planning. Before surgery, imaging of your hip or knee is used to create a three-dimensional model of your joint. Dr. Sloan plans your implant size, position, and alignment on that model — tailored to your anatomy, not an average.

2. Surgeon-controlled execution. During surgery, the robotic arm assists in positioning the instruments and making the bone cuts. The system can constrain the instruments to stay within the boundaries of the plan, which helps protect surrounding tissue.

3. Real-time verification. Throughout the procedure, the system provides live feedback on implant position and alignment, allowing adjustments to be made while there is still time to make them.

What the evidence actually shows

Dr. Sloan believes patients deserve a straight answer on this, because marketing around surgical robotics often outruns the evidence:

  • Precision: Across published studies, robotic assistance consistently produces more accurate implant positioning and fewer alignment outliers than conventional instruments. On this point, the evidence is strong.
  • How patients feel: Whether that precision translates into better pain, function, or satisfaction is less certain. Large randomized trials of robotic total knee replacement — including the RACER-Knee trial (339 patients across 10 hospitals) — found no clinically meaningful advantage in patient-reported outcomes at one to two years compared with conventional surgery.
  • Where robotics may matter most: Partial knee replacement, which is technically demanding, may be an especially good application for robotic assistance — and complex cases (severe deformity, dysplasia, revision surgery) may be where precision matters most of all.

The honest summary: robotics improves execution. The surgeon’s judgment still determines the plan — and the plan is what ultimately matters most.

Why Dr. Sloan uses robotic assistance

Dr. Sloan serves as Director of Robotics for Orthopedic Surgery at Emerson Health. His view, discussed in depth on the Joint Replacement Podcast, is that the real question isn’t “robot or no robot” — it’s what target the technology should be aiming at. He uses robotic assistance as part of a broader philosophy: combine precise execution with individualized planning based on your specific anatomy.

Over 2,000 robotic-assisted hip and knee replacements performed using the Mako system.

Is robotic-assisted surgery right for you?

Many patients having total or partial hip or knee replacement may be candidates for a robotic-assisted approach. The best way to find out is a consultation: Dr. Sloan will review your imaging, discuss your goals, and recommend the approach — robotic-assisted or conventional — that makes the most sense for your specific joint.

Robotic assistance is a tool, not a requirement. In experienced hands, conventional joint replacement remains an excellent operation. The recommendation will always be based on what’s best for you, not on the technology.

What to expect

  • Before surgery: CT imaging for 3D planning, medical clearance, and pre-operative education.
  • Day of surgery: Around 80% of patients having primary hip or knee replacement go home the same day.
  • Recovery: The recovery timeline is similar to conventional joint replacement — walking with assistance the day of surgery, with steady progress over the following weeks under the guidance of your physical therapy team.

Frequently asked questions

Does the robot do the surgery?

No. Dr. Sloan performs the entire operation. The robotic system assists with planning and precision — it never acts on its own.

Is robotic-assisted joint replacement better than traditional surgery?

It’s more precise, and that precision is well documented. Whether it produces meaningfully better pain relief or function is less clear in the current evidence — and any surgeon who tells you otherwise isn’t reading the studies. Dr. Sloan uses it where the evidence supports it and will tell you honestly when it doesn’t change the recommendation.

Does it cost more?

Robotic-assisted surgery can involve additional costs depending on your insurance plan. Our office will verify your coverage before surgery so there are no surprises.

Will I recover faster?

Recovery depends far more on your overall health, the surgical approach, and your rehabilitation than on whether a robot was used. Most patients are up and walking the day of surgery either way.

Do you use robotics for both hip and knee replacement?

Yes — robotic assistance can be used for total and partial knee replacement as well as total hip replacement, when appropriate for the individual case.

Related podcast episodes

Schedule a consultation

Considering hip or knee replacement? Meet with Dr. Sloan to discuss whether a robotic-assisted approach is right for you.

Schedule a Consultation or call 978-369-5391.