What Each Procedure Actually Replaces

The knee joint has three compartments. The medial compartment sits on the inner side — between the inner ends of the femur and tibia.

The lateral compartment sits on the outer side. The patellofemoral compartment is at the front, between the kneecap and the lower end of the thigh bone.

Arthritis can affect one, two, or all three of these compartments, and which compartments are affected determines which operation is appropriate.

Total knee replacement resurfaces all three compartments. The damaged cartilage and bone from the ends of the femur, the top of the tibia, and the underside of the kneecap are removed and replaced with a metal and plastic prosthesis.

The entire joint surface is new. This is appropriate when arthritis affects two or more compartments, or when the joint damage is too extensive to address partially.

Partial knee replacement — also called unicompartmental arthroplasty — replaces only the damaged compartment. The healthy cartilage, bone, and ligaments in the other compartments are left entirely untouched. Most commonly, the medial compartment is replaced. Lateral compartmental replacement is less common. Patellofemoral replacement is an option for isolated anterior knee arthritis.

The appeal of partial replacement is preservation. Patients retain the natural bone and cartilage in the healthy parts of their joint, and the cruciate ligaments — which are removed in total replacement — remain intact.

This produces a knee that moves more naturally and tends to feel more like the original joint than a total replacement does. The limitation is that it only works when damage is genuinely confined to one area.

Who Qualifies for Partial Replacement — The Exact Criteria

Not everyone with knee arthritis qualifies for partial replacement, and the criteria are specific. Your surgeon will make this determination based on your imaging — X-ray and MRI — and your clinical examination. The list below reflects the standard eligibility framework used at India's major joint replacement centres.

You may be eligible for partial knee replacement if:

Arthritis is confined to one compartment — typically the medial (inner) compartment, confirmed on weight-bearing X-ray. Your anterior cruciate ligament (ACL) is intact — this is critical, as partial replacement relies on the ACL for stability.

Your pain is primarily localised to the affected compartment rather than diffuse across the whole knee. You have a relatively normal range of motion — the joint bends and straightens reasonably well.

Your body weight is within a range your surgeon considers appropriate for the implant size and loading. You are generally willing to accept the possibility of future surgery if arthritis progresses to other compartments.

You will need total knee replacement if:

Arthritis affects two or three compartments. Your ACL or other major ligaments are damaged or absent.

You have severe valgus or varus deformity — significant bow-legged or knock-kneed alignment. Your pain is diffuse and not localised to one compartment.

Previous major knee surgery has compromised the remaining structures. Inflammatory arthritis — rheumatoid arthritis, for example — rather than osteoarthritis is the primary diagnosis.

Pros and Cons — The Honest Comparison

Neither procedure is universally superior — they serve different patient situations. The comparison below is honest about the trade-offs of each.

Partial knee replacement — advantages

Partial replacement preserves more of the natural knee. The cruciate ligaments remain.

Healthy cartilage and bone in the unaffected compartments stay in place. Patients consistently report that a partial replacement feels more natural — closer to the original knee — than total replacement.

Studies confirm that patients with partial replacement tend to achieve better functional scores on activities requiring a full range of motion, like climbing stairs or getting up from a low chair.

The surgical approach is less invasive. The incision is smaller.

Blood loss is lower. Hospital stay is two to three nights rather than four to five.

Recovery is significantly faster — most partial replacement patients reach normal daily activities in six to eight weeks compared to three to six months for total. For international patients travelling to India, this shorter recovery means a shorter required stay — two to three weeks rather than three to four.

Partial knee replacement — disadvantages

The primary limitation of partial replacement is that arthritis can progress. If the disease spreads to the other compartments in the years after partial replacement, revision surgery may be needed — converting the partial to a total.

This is a more complex operation than a primary total replacement because the prior implant and any scarring need to be managed. Revision rates for partial replacement are higher than for total over a 15 to 20 year horizon, though at 10 years the Oxford system's 97.8 percent survival rate compares well.

Patient selection is also stricter. The eligibility window for partial replacement is narrower than for total — if your arthritis has spread even slightly beyond one compartment, or if your ACL has any significant damage, you are disqualified.

This narrows the pool of patients who can benefit. Only a minority of knee arthritis patients — estimates vary from 20 to 40 percent — genuinely meet the criteria for partial replacement at the time of their first assessment.

Total knee replacement — advantages

Total replacement addresses the whole joint in one operation. There is no risk of needing a second procedure because arthritis has progressed to another compartment — the whole surface has been replaced.

The revision rate over 15 to 20 years is lower than for partial replacement. For patients with multi-compartment arthritis, total replacement is the only appropriate option, and for most patients with severe knee arthritis, it represents the definitive long-term solution.

Total replacement also provides more predictable relief from the specific symptom of diffuse pain — if pain is coming from multiple compartments, only a procedure that addresses all of them can resolve it completely.

And because total replacement is performed more frequently, the surgical experience base and data supporting outcomes is broader and deeper than for partial replacement.

Total knee replacement — disadvantages

Total replacement removes healthy bone and cartilage along with the damaged portions. The cruciate ligaments are taken out.

The result is a functional knee, but one that — in most cases — does not feel quite as natural as the original. Range of motion may be slightly less than partial replacement, and some patients describe total replacement as feeling more mechanical.

Recovery is longer and more demanding. For international patients, the in-India stay requirement of three to four weeks is a meaningful practical commitment compared to two to three weeks for partial.

Cost in India — What Partial Saves You vs Total

Partial replacement is less expensive than total in India — the surgery is shorter, the hospital stay is two nights rather than five, and the implant is simpler.

For international patients who qualify, this cost difference compounds with the shorter required stay in India — less accommodation, fewer physiotherapy sessions, and less time away from home or work.

All India costs include surgery, implant, hospital stay, surgeon, and anaesthesia. Standard implant included. Oxford PKR or equivalent brand used at JCI hospitals. May 2026. Exchange rate: £1 = approx. USD 1.27.

Recovery — How the Timelines Differ

The recovery difference between partial and total replacement is one of the most practically significant distinctions for international patients. Partial replacement's shorter recovery means a shorter required stay in India — which reduces accommodation costs, reduces time away from work or family, and for many patients makes the decision to travel for surgery more manageable.

Recovery timelines are averages — individual outcomes vary based on patient age, fitness, pre-operative mobility, and physiotherapy engagement. Data from GAF Healthcare partner hospitals and published orthopaedic literature.

Having Either Procedure in India — Hospitals and Practical Details

Both partial and total knee replacement are performed at GAF Healthcare's JCI-accredited partner hospitals in Delhi NCR at internationally accredited standard. The partial replacement programme at Max Saket Delhi — the first hospital in India to introduce minimally invasive knee techniques — and at Fortis FMRI Gurgaon are both well established.

Medanta Gurgaon and Apollo Delhi perform both procedures with robotic MAKO assistance available for either surgery type.

One important practical note: GAF Healthcare reviews your imaging before you travel.

This matters specifically for the partial versus total question because the candidacy assessment for partial replacement requires careful imaging review — patients who travel to India expecting partial replacement and then discover in pre-operative assessment that their arthritis is too extensive for it are in a difficult position.

Sending your X-ray and MRI before booking ensures you travel with the right surgical plan confirmed, not discovered on arrival.

"I was 61 and my left knee hurt mainly on the inner side. I had read about partial knee replacement and wanted it — it sounded less invasive and the recovery seemed manageable for someone still working. I sent my MRI to GAF Healthcare before booking. The specialist confirmed I qualified — one compartment affected, ACL intact, good alignment. I had the partial replacement at Max Saket. Three weeks in India. I flew home to London. Six weeks later I was back at my desk. The knee feels close to normal. I am glad I did not default to total."