India's 1st robot-assisted cementless knee replacement at Delhi hospital. What sets the procedure apart

The Print

03-07-2025

Led by Dr Sujoy Bhattacharjee, chairman of the Max Institute of Robotic Joint Replacement, the surgical team opted for a cementless implant, using the CUVIS robotic system for precise alignment and placement of the implant, tailored to the patient's unique anatomy. 'We use markers and trackers to guide the robot during surgery,' Dr Bhattacharjee told media persons Wednesday.
The procedure was performed Monday on a 54-year-old patient from Jharkhand suffering from advanced osteoarthritis and severe knee deformities such as bow-leggedness (varus) and restricted knee extension (flexion).
New Delhi: Doctors at the Max Super Speciality Hospital in Delhi's Saket have successfully performed the country's first robot-assisted cementless medial pivot knee replacement, marking a major milestone for joint replacement surgery in India.
He said that the goal was not just to replace the knee, but to preserve key structures, especially ligaments, including the posterior cruciate ligament, which plays a critical role in knee stability.
A robot-assisted cementless medial pivot knee replacement is an advanced surgical technique that combines precision robotics with an implant design that closely replicates the natural movement of the human knee. Unlike traditional knee replacements that use bone cement to fix the implant, the cementless approach enables the patient's natural bone to grow into the implant, enhancing long-term stability and durability.
This combination of robotic precision, cementless fixation and anatomical design results in faster recovery, reduced post-operative pain, and improved overall joint function.
Dr Bhattacharjee demonstrated how a normal knee consists of three bones working in coordination—the upper, lower and the kneecap—with movement supported by two main ligaments, the anterior and posterior cruciate.
In traditional surgeries, the implant is fixed using bone cement, but in this case, they opted for a cementless implant made of titanium, which allows the bone to grow naturally into the surface.
Using real-time data from the Optical Tracking System (OTS), the surgical team monitored the 'gap', the space between the implant and bone, at every angle of knee movement, whether sitting or standing.
Dr Bhattacharjee explained that they first place a trial implant to assess alignment and mobility, and proceed with the final implant only after confirming that the gaps remain consistent at all angles.
'That's the beauty of robotic surgery; it's precise, evidence-based and fully trackable,' he said, noting that post-operative mobility in the patient's leg was excellent, with a smooth range of motion.
Doctors at Max claimed that theirs was the world's first robot-assisted cementless medial pivot knee replacement. However, in June 2022, Smith+Nephew, a global medical technology company, had already performed what was widely reported as the world's first robot-assisted cement-free total knee replacement.
On 30 June that year, Dr Cyna Khalily in Louisville, Kentucky, used the LEGION CONCELOC cementless implant in combination with the CORI surgical robot for the procedure. The surgery eliminated the need for bone cement and employed a handheld robotic tool to precisely prepare the bone.
Dr Bhattacharya clarified that the distinction lay in the type of robotic system used. The CORI system in the 2022 surgery, he said, was a passive robot controlled and guided manually by the surgeon. In contrast, the system used in the Max procedure was an active robot, capable of independently executing pre-programmed movements, which, according to him, sets it apart as a global first of its kind.
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Faster recovery, less chance of loosening
Highlighting the benefits of a non-cemented implant, Dr Bhattacharjee said the procedure is quicker because it eliminates the 12-15 minutes usually needed for cement to set. 'In bilateral knee replacements, this alone can save nearly 25 minutes.'
The implant bonds directly with the bone, without any cement in between, leading to stronger, more natural integration and better long-term outcomes.
He noted that while cement can sometimes compensate for small surgical errors, cementless implants leave no room for error, making surgical expertise crucial.
The added benefits include a lower risk of infection, reduced hospital stay as well as faster and smoother recovery due to the biological bonding process.
Dr Ankush Sharma, clinical associate and part of Dr Bhattacharjee's team, explained that cementless implants are designed with microscopic pores. 'The patient's bone grows into these pores, locking the implant in place naturally,' he said.
In contrast, cemented implants rely on an artificial bond. Cement sticks to both the implant and the bone, but the bone doesn't grow into it.
'Over 10 to 20 years, that cement bond can weaken and lead to loosening,' said Dr Sharma. But with a cementless implant, once bone growth secures it, the chances of loosening are drastically reduced.
(Edited by Sugita Katyal)
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