FAQ (Hip and Knee) ​

Most frequent questions and answers

Arthritis means destruction of the joint due to damage to the cartilage, which exposes the underlying bone. Progressive destruction of the joint leads to wearing off of the bone.

Common types of arthritis are osteoarthritis (OA) and rheumatoid arthritis (RA).

Patients with mild to moderate arthritis can be usually treated with painkillers, physiotherapy and lifestyle modifications.

However, in severe arthritis, medications will relieve pain only for a short duration, while their prolonged use will be harmful to the stomach, liver and kidneys. In such cases, one may consider joint replacement surgery as an effective and permanent solution. THR or TKR can relieve pain and restore the patient to near-normal level of daily activities.

The hip joint has two components – the acetabulum (socket) and the femoral head (ball). THR means replacing both these components with artificial parts made of metal, plastic or ceramic. The artificial parts move smoothly against each other and give complete relief from hip pain.

Common reasons for doing a THR are

  •  Osteoarthritis (OA) of the hip
  •  Rheumatoid Arthritis (RA) of the hip
  •  AVN (avascular necrosis) of the femoral head
  •  Femur neck fracture in elderly patients (as an alternative to Bipolar Hemiarthroplasty)
  • Dysplastic Disease of the Hip (DDH)
  • Ankylosing Spondylitis affecting the hip

The knee joint is made up of ends of the femur (thigh bone), the tibia (leg bone) and the patella (kneecap). In TKR, the ends of the femur and tibia which rub against each other are replaced with artificial parts made of metal and plastic. In addition, the undersurface of the patella is sometimes replaced with a plastic cap. The artificial parts move smoothly against each other and give complete relief from knee pain.

Common reasons for doing a TKR are

  • Osteoarthritis (OA) of knee
  • Rheumatoid Arthritis (RA) of knee

You may need joint replacement surgery (hip or knee) in the following situations:

  • Severe pain troubles you in daily activities such as walking, sitting cross-legged, climbing or descending stairs, or getting up from a sitting position
  • Pain-killers are required almost daily, and give only temporary relief
  • Physiotherapy and lifestyle modification are not helpful in alleviating pain

With proper care an artificial hip or knee joint will last for about 20 years. The longevity of the artificial joint is reduced if you are overweight or do excessive physical activities.

The success rate of joint replacement surgery is extremely high.

However, the result can be influenced to some extent by several factors like severity of the initial disease, bone quality, status of surrounding muscles and ligaments and adherance to post-operative instructions by the patient.

Patient motivation to comply with the exercise program after surgery is very important to ensure a good result. A positive outlook towards the surgery is also very important.

Overall, most patients are extremely happy with results of joint replacement surgery.

Femoral Stem: Metal (Cobalt-chrome or Titanium), sometimes with Hydroxyapatite coating or porous Titanium coating
Femoral Head: Metal (Cobalt-chrome), Ceramic (Alumina), or Metal-Ceramic (Oxidized Zirconium)
Acetabular Liner: Plastic (Cross-linked Polyethylene), Ceramic (Alumina) or Metal (Cobalt-chrome)
Acetabular Cup: Metal (Titanium), sometimes with Hydroxyapatite coating or porous Titanium coating, or All-Poly cup (Cross-linked Polyethylene)

Femoral Component: Metal (Cobalt-chromium-molybdenum) or Metal-Ceramic (Oxidized Zirconium)

Insert: Plastic (Cross-linked Polyethylene)

Tibal Base-plate: Metal (Titanium or Cobalt-chrome)

Patellar Component: Plastic (Cross-linked Polyethylene)

No. The large multinational companies which manufacture these implants follow strict industry standards, and the same implant is used all over the world.

However, the implant price may vary in different countries, depending on cost of living, local taxation laws and expenditure related to transport / handling / storage.

The artificial joint (hip or knee) implanted in your body will eventually become loose from its bony contact. This happens after about 20 years, and the patient may require a revision surgery at that stage. In certain circumstances like severe osteoporosis, loosening can occur earlier (as early as 8 – 10 years).

The two moving parts of the implant which come in contact with each other constitute the ‘bearing surface’ of the artificial joint.

In the hip, the bearing surface is between the femoral head and the liner in the cup. In the knee, the bearing surface is between the metallic femoral component and the plastic tibial insert.

With continuous use of the artificial joint over several years, there is damage to the bearing surface. This is called ‘wear’ of the implant, and it may require us to do a revision surgery after 20 years.

Air travel should be avoided for the first 4 weeks as the risk of deep vein thrombosis is higher. If travel is unavoidable, you should go by road or rail.

Domestic flights within the country are allowed after 4 weeks. After 6 weeks, short flights (e.g. Mumbai to Europe) are allowed. Long haul flights (e.g. Mumbai to USA) are allowed only after 3 months.

Metal detectors at the airport will go off because of the metallic implant in your body, so it is advisable to carry a certificate from your doctor with you.

All major operations involve some risk. With current advances in surgical techniques and anaesthesia, the risks are quite low. Patients should be aware of the rare complications like infection, blood clots and medical issues. For more information on these, please refer to the individual sections on risks of total hip replacement and risks of total knee replacement.

Yes, but only in selected cases. Usually, hips are operated one at a time.

Yes, but only in selected cases. Bilateral (both sides) knee replacement has the advantage of a shorter overall recovery period, but the anaesthesia risk is increased slightly.

The use of computer to ensure correct alignment and component placement is called Computer – Assisted Surgery (CAS) or Navigation. During surgery, the computer ‘registers’ in its databank the individual details of the patient’s anatomy with the help of infra-red rays. Then the computer guides the surgeon to accurately place the implants in correct alignment.

Separate computer softwares are available for the hip and knee. However, most surgeons today do not use CAS for hip replacement.

CAS is very popular for knee replacement. However, the surgeon has to be specially trained in computer-assisted surgery. Also, one must note that conventional total knee replacement (without CAS) is also very accurate and reliable.

This is an advanced tool in knee replacement surgery. Briefly, it is similar to computer navigation (CAS), but the computer does all its work one month before the surgery. An MRI Scan or CT Scan of the knee is done, and the data are fed into the computer. Based on these data, the computer then creates a digital ‘mould’ for the instruments used for cutting the bones in TKR surgery. The instruments are specially manufactured for an individual patient, and are discarded after the surgery. This obviously takes time, and it significantly increases the cost. More research is going on about this technology.

You will be discharged from the hospital in 4 to 5 days after the surgery. Most patients are walking with the aid of a walker within 48 hours after the operation. The main purpose of the walker is to prevent a fall. The implant is strong enough to sustain the body weight of the patient.

The walker is replaced by a stick in about 3 weeks, and the stick is used for another 6 weeks. In approximately two months after the surgery, the patient is very comfortable and is walking independently.

Most patients are walking with the aid of a walker within 48 hours after hip or knee replacement.

Usually, the operation is done under spinal anaesthesia, but sometimes general anaesthesia is required. An epidural is sometimes coupled with spinal anaesthesia.

The patient is usually discharged in 4 – 5 days.

  • First visit at 2 weeks for suture / staple removal.
  • Second visit at 6 weeks.
  • Third visit at 3 months.
  • Fourth visit at 6 months.
  • Fifth visit at 1 year.

Thereafter, you should meet your doctor once every year.

There will be some post-operative pain, which lasts for 2 – 3 days, and it is controlled with painkillers.

(a) Antibiotics
(b) Blood-thinners
(c) Pain-killers
(d) Specific medication for conditions like diabetes, heart disease and hypertension

Hip: X-Ray PBH (Pelvis with Both Hips) and X-Ray Both Hips Lateral

Knee: X-Ray Both Knees AP (Standing), X-Ray Both Knees Lateral and X-Ray Both Knees Skyline View.

It is a good practice to get these X-Rays done before you come for consultation, as it saves time.

Generally, blood transfusion is not required, except in cases when the haemoglobin level is very low (< 9 gm %) or if there is much blood loss during surgery. However, it is prudent to make arrangements for one unit of blood in advance.

In most cases, after a 4-week leave, you can resume your work.

After a hip or knee replacement, you can easily walk for about 2 km and climb or descend stairs easily. You can also do activities like swimming and driving a car. You can play light sports like golf, table tennis and badminton.

Usually you can drive within 6 to 8 weeks following the operation, after being assessed by your doctor. If your left knee was operated and your car has automatic transmission, you may drive in 4 weeks.

The cost is divided into 4 parts:


(a) Cost of the artificial implant

(b) Hospital fee (includes surgeon fee, anaesthesia fee, operation theater charges and staying charges)

(c) Cost of medicines

(d) Cost of investigations

The hospital fee is usually clubbed together with the cost of medicines and investigations as a cost-effective package.

You should discuss the issue with your surgeon. Most surgeons and hospitals will be co-operative towards a genuinely non-affording patient. Hospitals run by charitable trusts offer subsidized rates for some patients.

Most people who undergo hip or knee replacement are above the age of 55 years. However, in special circumstances, even younger patients require this surgery.

As mentioned above, most patients who undergo hip or knee replacement are above the age of 55 years. But if you are younger than 50 years, and yet you have severely disabling arthritis, you should consider getting operated now. The present generation implants are already of such good quality that they will last 20 years. In case you need a revision (re-do) surgery after 20 years, it can still be done. Also, by that time, the technology of revision surgery (which gives a good result even now) will be still more advanced.

First and foremost, other causes of hip and knee pain must be ruled out. The pain may be referred from a spinal (back) problem. If the X-Rays do not show significant damage, then probably surgery is not required immediately, and you can wait for a few years.
If you don’t have significant pain, then the surgery should be delayed. Pain, rather than the X-Ray, is the more important parameter in assessing the need for surgery.

Most definitely yes. The quality of life dramatically improves after a successful joint replacement surgery. Many patients more than 90 years old have also been operated and have enjoyed the benefits of the procedure.

Most cardiac problems and hypertension can be managed today with appropriate medications. Some patients may require procedures like coronary angioplasty or CABG for poor heart condition. None of these conditions precludes you from having a joint replacement surgery. However, the risk factor is definitely more.

Therefore, you have to consider the relative risk versus the potential benefit that you will derive from the joint replacement surgery. If you feel that the risk is simply too big, then you should not consider surgery.

If you have severe arthritis in your hip or knee, joint replacement surgery is usually the best option. With current medical care and advances in implant design, it is extremely safe and rewarding.

However, if you are psychologically unprepared for surgery, then no one can force you to get operated. You may try any other legitimate treatment options like homeopathy or ayurveda. You should avoid prolonged use of painkillers to protect your kidneys and liver.

You may undergo joint replacement surgery even if you are overweight. After the surgery, you should get into a weight reduction program to prolong the life of your artificial implant.

You may undergo joint replacement surgery even if you have osteoporosis. After the surgery, you must take calcium and mineral supplements to strengthen your bones.

There is no ‘miracle cure’ for the treatment of arthritis.

It is perfectly all right to try any legitimate pain-relieving therapy provided it does not harm your body. But just because something new or exotic is available does not mean that it is good.

Certainly. Joint replacement is an elective surgery, and waiting for a short time (say, 3 to 4 months) is perfectly all right.

Not at all. After joint replacement surgery, supervised care is required only for a short duration (2 weeks or less). This can be arranged jointly by your surgeon, nurses and physiotherapist. After that, you will be able to take care of yourself on your own.

You must select a good surgeon and a hospital with a good infrastructure. The surgery can be arranged either through the surgeon’s office or through the hospital.