How long does knee replacement surgery take? For most patients, the operation itself takes one to two hours, whether it is a conventional or MAKO robotic procedure. Total time in the operating suite, including anaesthesia, positioning and closing, usually runs closer to two to three hours. This guide breaks down what happens at each stage of knee replacement surgery in Thailand, how long you can expect to stay in hospital, and how the full timeline compares with the wait for surgery back home in Australia.
The Quick Answer: Surgery Time at a Glance
Knee replacement surgery time depends mainly on the type of procedure and whether robotic technology is used. Here is how the main options compare:
| Procedure type | Typical surgery time |
| Partial knee replacement | 45 minutes to 1 hour |
| Total knee replacement (conventional) | 1 to 2 hours |
| MAKO robotic knee replacement | 1 to 2 hours |
| Bilateral knee replacement (both knees) | 3 to 4 hours combined |
| Revision knee replacement | Up to 3 hours |
These figures cover the time the surgeon is actively operating. Add roughly 45 minutes to an hour either side for anaesthesia, theatre preparation and initial recovery, and a single knee replacement typically occupies two to three hours of theatre time in total.
Step by Step: What Happens During Knee Replacement Surgery
Knee replacement follows a consistent sequence regardless of hospital or surgeon. Understanding each step helps make sense of where the time actually goes.
- Anaesthesia and positioning (15 to 20 minutes). You receive either general or spinal anaesthesia, then are positioned on the operating table with the leg secured for access.
- The incision. The surgeon makes an incision over the front of the knee, typically 10 to 20 centimetres for conventional surgery, or shorter for minimally invasive and MAKO techniques.
- Removing damaged bone and cartilage. Worn cartilage and a thin layer of bone are removed from the end of the thigh bone, top of the shin bone, and sometimes the kneecap.
- Shaping and fitting the implant. The bone surfaces are precisely shaped to match the artificial components, which are then fitted and secured, often with bone cement.
- Testing movement and alignment. The surgeon bends and straightens the new joint to check alignment, stability and range of motion before closing.
- Closing the incision. Layers of tissue and skin are closed and a dressing applied before you are moved to the recovery room.
If you would like a fuller breakdown of the terms used at each stage, our knee surgery terminology guide explains what surgeons mean by terms like resurfacing and component fixation.
What Affects How Long Your Surgery Takes
A few factors explain why one patient’s surgery might take 90 minutes and another’s closer to three hours:
- Total vs. partial replacement – A partial knee replacement, which resurfaces only the damaged section of the joint, is usually quicker than a total replacement. Our guide to total vs. partial knee replacement explains how surgeons decide which one you need.
- Robotic vs. conventional technique – MAKO robotic surgery adds pre-operative CT scanning and computer planning, but operating time itself is comparable to conventional surgery.
- One knee vs. both knees – Patients having both knees replaced in the same session, known as bilateral knee replacement, should expect roughly double the operating time. See our guide on having both knees replaced at once for what that involves.
- Revision surgery – Replacing a knee implant that has already been operated on takes longer than a first-time replacement, due to scar tissue and existing hardware.
- Individual anatomy and complexity, including body weight, bone quality, and the degree of joint deformity, can all extend surgical time.
- Surgeon and hospital experience matters too. High-volume orthopaedic centres tend to have more consistent, efficient theatre times.
MAKO Robotic Knee Replacement: Does It Take Longer?
A common assumption is that robotic-assisted surgery takes noticeably longer than conventional surgery. In practice, MAKO robotic knee replacement typically takes about the same one to two hours in theatre. The main difference happens before surgery day: a CT scan is taken in advance and used to build a 3D model of your knee, which the surgeon uses to plan bone cuts and implant position ahead of time.
During the operation, the robotic arm follows that pre-set plan within haptic boundaries, guiding the surgeon’s cuts rather than replacing their judgement. This planning stage is what allows for the precision robotic surgery is known for, without meaningfully extending time on the table. If you are weighing up which approach suits your knee, our comparison of robotic vs. conventional knee replacement covers the differences in more depth.
Surgery Time vs. Total Time in the Theatre
It helps to separate two different numbers patients often confuse:
- Cutting time – how long the surgeon is actively operating (one to two hours for most knee replacements).
- Total theatre time – everything from the moment you enter the operating suite to the moment you leave, including anaesthesia, positioning, prepping the leg, the operation, and initial recovery room monitoring.
Total theatre time is usually two to three hours, sometimes longer if anaesthesia takes extra time to establish or if additional imaging is used during the procedure. According to the NHS, a standard knee replacement operation usually takes about one to two hours of active surgery.
How Long Will You Be in Hospital After Surgery
After the operation, most patients spend three to five days in hospital before being discharged. Early mobilisation is a priority; you will typically be encouraged to stand and take a few steps with a walker within 24 hours of surgery, supported by a physiotherapist. At Phyathai 2 International Hospital, JCI-accredited since 2014, and KDMS Hospital, Thailand’s first dedicated bone and joint hospital, this early-mobilisation approach is standard practice for both conventional and MAKO robotic patients.
For international patients travelling for knee replacement surgery, the hospital stay is only part of the picture. Most patients remain in Thailand for 10 to 14 days in total: the initial hospital stay, followed by several nights nearby for wound checks and physiotherapy before your surgeon issues a fit-to-fly clearance. Our guide on how long after knee replacement you can fly covers exactly what that clearance involves and how to plan the return flight safely.
It is also normal to notice swelling during this period. Our article on swelling after knee replacement explains what is typical and what warrants a call to your care team.
Preparing for Surgery Day: What Happens Before the Clock Starts
The one to two hours in theatre is the shortest part of the overall process. Most hospitals ask patients to arrive several hours before surgery for final checks, including bloodwork, marking the correct leg, and a final review with the anaesthetist. A thorough pre-surgery routine, covering fasting times, medication adjustments and pre-operative exercises, makes a real difference to how smoothly the day goes. Our pre-surgery checklist and exercise guide walks through exactly what to prepare in the weeks before your procedure.
The Bigger Timeline: What This Means for Australian Patients
For Australians, “how long does it take” often means something bigger than the hours in theatre. According to the Australian Institute of Health and Welfare, the national median wait for public total knee replacement was 209 days in the 2024 to 2025 reporting period, with some patients waiting considerably longer depending on their state and category.
Choosing knee replacement surgery in Thailand changes that timeline significantly. Once assessment and travel are arranged, many patients can have surgery scheduled within a matter of weeks, then return home within two to three weeks with their recovery well underway. If you are comparing the full cost picture alongside the timeline, our guide to what a knee replacement costs in Australia breaks down how private, public and overseas options compare.
Every patient’s timeline looks a little different, and your surgeon is the best source for an estimate specific to your knee. If you would like a personalised assessment of your surgery time, hospital stay and full trip length, get in touch with our team and we will help you plan the details.
Frequently Asked Questions about Knee Replacement Surgery Timing
How long does total knee replacement surgery take?
Most total knee replacements take one to two hours of active surgical time, with two to three hours of total theatre time once anaesthesia and preparation are included.
How long does a partial knee replacement take?
Partial knee replacement is typically quicker, usually 45 minutes to an hour, since only the damaged section of the joint is resurfaced.
How long does MAKO robotic knee replacement take?
About the same as conventional surgery, one to two hours, though a CT scan and surgical planning happen in the days beforehand rather than adding time on the table.
How long will I be in hospital after knee replacement?
Most patients stay three to five days in hospital, with early walking encouraged within the first 24 hours.
How soon can I fly home after knee replacement surgery in Thailand?
Most international patients need 10 to 14 days in the country before their surgeon issues a fit-to-fly clearance, covering the hospital stay plus follow-up physiotherapy.
How long does it take to have both knees replaced at once?
Bilateral knee replacement, where both knees are replaced in a single session, typically takes three to four hours combined, roughly double a single-knee procedure.