Dr Tarandeep Singh Gill — MS Ortho, MCh Ortho
Director – Joint Replacement & Robotic Surgery · RoboLens FT3D Pioneer · Max Super Speciality Hospital, Mohali
Every patient who hears “no CT scan needed” asks the same follow-up question: how does that work?
It’s a fair question. The standard understanding of robotic knee surgery is that you need a pre-operative CT scan to feed 3D data into the system. Without a scan, how does the robot know where to go?
The Problem with Pre-Operative CT Scans
Most robotic systems require a CT scan taken 1–4 weeks before surgery. That scan is used to build a virtual 3D model of the joint, which the surgical team uses to plan implant positioning and the bone cuts needed to achieve it. On surgery day, the robot executes that pre-built plan.
The weakness in this approach is the gap between planning and execution. A knee in a CT scanner — lying flat, unloaded, unswollen — is not the same as a knee on the operating table. Soft tissues shift with positioning. Swelling varies. Deformity that looks like X degrees in a scan may need more or less correction when the surgeon actually opens and sees the joint. The pre-operative plan is a best estimate, executed precisely — but it’s an estimate.
How RoboLens FT3D Gets the Data Without a CT Scan
FT3D — Fluoroscopy-Tracked Three-Dimensional — uses intraoperative imaging. During surgery, as the procedure is underway, the system acquires live fluoroscopic images of the actual joint from multiple angles. These images are processed in real-time to build a 3D model of the knee as it is at that moment — not as it was in a scan taken weeks earlier.
The surgical planning is then done live, with this current data. The system tells Dr Gill exactly where to make each cut, how much bone to remove, and what angle and depth to use for the implant. If the anatomy looks different from the pre-operative X-ray prediction — as happens with deformed knees — the live imaging captures that immediately and the plan adjusts.
This is the fundamental advantage of intraoperative imaging over pre-operative CT: the data is current, not historical.
What This Means for the Patient
No pre-operative CT scan means less radiation. A knee CT protocol delivers approximately 1–3 mSv — not catastrophic, but not nothing. For younger patients having bilateral knees done, eliminating this step reduces total radiation exposure meaningfully.
It also means a simpler pre-surgical workup. No separate CT appointment to arrange. No waiting 1–2 weeks for the 3D model to be processed by the manufacturer. The pathway from consultation to surgery is more direct. For patients who have been in pain for months and want to move forward, that matters.
And for the surgery itself, the live imaging means that what the surgeon plans is based on what he actually finds in the joint — not what was predicted before he opened. In complex cases — significant deformity, previous knee surgeries, unusual anatomy — this adaptability is a genuine advantage over pre-planned approaches.
Dr TS Gill is the pioneer of RoboLens FT3D in North India. The procedure is available at Max Super Speciality Hospital, Phase 6 (Sector 56), Mohali. New patient consultations include X-ray review, clinical examination, and a clear explanation of which procedure fits your specific knee. Book at tsgillortho.com/appointment or call +91-82880 15106.
