Total Joint Replacement

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Computer-Assisted Navigation System


Computer assisted joint replacement surgery is perhaps the most important breakthrough in the history of artificial joint replacement. Using the computer, a precise model of the patient's diseased joint can be constructed in a very short period of time during the operation and therefore allows very accurate positioning of the artificial joint implants and thus greatly improves the clinical outcome and longevity of the artificial joint. The technique is now widely used in knee and hip replacement surgery with excellent results.

Total Knee Replacement
What is a total knee replacement?
In total knee replacement, the damaged joint surfaces of the knee are removed. Metallic and special plastic prostheses are then put on the joint surfaces.

When would a total knee replacement be required?
When the knee joint is badly damaged and other treatment methods cannot help to relieve the symptoms, total knee replacement may help to solve the problem. It aims to relieve pain and regain motion in the knee joint. The walking ability of the patient will usually be greatly improved after the operation.

Common diseases causing advance damage of the knee joint:
  • Primary osteoarthritis related to age
  • Rheumatoid arthritis
  • Post-traumatic arthritis

How long can the total knee replacement last?
Based on the past experience, we are expecting the newly designed implants to last for around 15 to 20 years. The longevity of the implants also depends on how vigorous one is using the replaced knee.

What is the navigation system and how does it help total knee replacement?
The navigation system basically consists of a computer, the infrared camera emitting and receiving infrared signals, the instrument with markers that reflect infrared signals and the specifically designed soft ware for individual operation.

In total knee replacement, the system can make use of the infrared technology to produce a model of the knee joint of the patient during the operation. Making use of the special soft-ware, we know exactly where to cut the bones. This will in turn helps the surgeon to put in the prosthesis in the best position. A properly positioned total knee prosthesis will last longer.


Minimal invasive total knee replacement
Total knee arthroplasty techniques are evolving and surgeons are using smaller incision to perform the same operation. It also aims to reduce the surgical trauma to the soft tissues and, hence, a faster recovery.

       After                 Before

Pre-operative preparations
  • General body check like blood tests, ECG, Chest X-ray
  • Stabilization of existing diseases like hypertension, diabetes mellitus, heart disease, etc.
  • Elimination of the possible septic focus in the body. Common areas requiring attention include to treat dental caries, fungal infection of the feet and urinary tract infection.

Post-operative preparations
  • Three to fours hours after the operation, when the condition is stable, the patient can start eating. Patients usually prefer to take light food like congee or soup. An intravenous drip will usually be kept for the first day to replenish the fluid loss.
  • Adequate analgesics will be given to the patient. The pain in the knee may last for around three to four days.
  • There will be drains leading from deep inside the wound to the plastic bottles at bedside. These help to remove the blood clots within the knee joint after the operation. These will be removed in two to three days after the operation.
  • If the patient cannot pass urine, he/she may require a urinary catheter. It will usually be removed in two to three days.
  • Breathing and mobilization exercises of the lower limbs are encouraged to prevent chest infection and deep vein thrombosis.
  • By the second day after the operation, many patients can sit out in a chair. Some can start walking with assistance from the physiotherapists. Appropriate walking aids would be arranged.
What are the potential complications and risks of the operation?
The rate of serious complications following total knee replacement is around 1-2%. The common ones are:
  • Heart attack, stroke, etc.
  • Wound infection or delayed wound healing
  • Excessive bleeding
  • Deep vein thrombosis, pulmonary embolism, fat embolism
  • Fractures
  • Nerve palsy
  • Loosening of the prosthesis, etc   

Related prosthetic & orthotic services

A leg sling will be provided to support the problem leg, thus early in-bed exercise can be processed in order to fasten the rehabilitation progress as well as swelling controlling.

Robotic Knee Replacement
Robotic Interactive Orthopaedic (RIO) System for Partial Knee Replacement
The knee joint is composed of three parts: patellofemoral joint, medial and lateral femorotibial joints. Due to different reasons, the knee joint may be totally or partially damaged. Total Knee Replacement can be performed if the whole joint is affected and other treatments have failed. Partial Knee Replacement can be considered as one form of treatments if part of the joint deteriorates.

Computer-assisted navigation system (CANS) has been widely used in Total Knee Replacement for about 10 years with very good clinical results. On the other hand, robotic surgery in medical science has undergone rapid development. Recently, Partial Knee Replacement has experienced a new breakthrough with the combination of CANS and robots.

In the past, Partial Knee Replacement was not widely practised by orthopaedic surgeons mainly because the positioning of implants is often suboptimal which may affect the long-term outcome of the operation. The Robotic Interactive Orthopaedic System (Makoplasty) synergises the advantages of both CANS and robots to achieve high precision and accuracy during surgery. The error in positioning assessment is less than 1 mm or 1 degree.

Before the Robotic Partial Knee Replacement, the patient has to perform a CT scan of the knee. The information is then analysed by special software in the system computer to generate a 3D model of the knee. Based on these data, surgeons can formulate pre-operative planning to ensure accurate positioning of implants.

With CANS, surgeons will assess the soft tissue tension of the knee joint during surgery, fine-tune the bone cuts required and achieve high precision in implants positioning. When everything is well planned, the surgeon then guides the robot to remove the damaged knee bone surfaces. Finally the implants will be cemented in position.

What Are the Advantages of RIO Partial Knee Replacement?
  1. It is relatively minimally invasive with a small wound, less pain and faster recovery
  2. Less bone and soft tissues of the knee are removed, thus preserving function of the joint
  3. Decrease the difficulty of a Total Knee Replacement if there is a need in future

X-Ray Images of the Knee before Robotic Unicompartment
Knee Replacement

X-Ray Images of the Knee after Robotic Unicompartment
Knee Replacement

What Are the Indications for RIO Partial Knee Replacement?
When the knee joint is partially damaged and other forms of treatment have failed, Robotic Interactive Partial Knee Replacement can be conducted. Common diseases causing partial knee joint damage include:

  • Primary osteoarthritis of the knee
  • Osteonecrosis of the femoral condyle
  • Post-traumatic knee arthritis

With the RIO System, surgeons can replace just the patellofemoral joint, the medial or lateral femorotibial joint, or a combination of these joints.

What Are the Potential Complications and Risks of the Operation ?
The risk of serious complications from RIO Partial Knee Replacement is low. Common ones include:
  •  Heart attack, stroke, etc.
  •  Wound infection
  • Excessive blood loss
  • Deep venous thrombosis, pulmonary embolism and fat embolism
  • Fracture
  • Neurovascular damage
  • Loosening of implants, etc.

Robotic Interactive Orthopaedic System (Makoplasty)

Total Hip Replacement
What is a total hip replacement?
Total hip replacement is to replace the diseased hip joint with an artificial joint. If the hip has been damaged, common activities such as walking or getting in and out of a chair may be painful and difficult. If the use of medications, changes in your everyday activities, and the use of walking aids are not helpful, you may want to consider hip replacement surgery.

Total hip replacement can relieve pain and allow one to resume normal everyday activities. The artificial joint usually lasts for about 10 to 15 years.

Common Indications for Total Hip Replacement
  • Osteoarthritis of the hip
  • Rheumatoid arthritis
  • Avascular necrosis of the femoral head
  • Fracture neck of femur
  • Benign or malignant tumours affecting the hip joint
  • Other arthritic diseases of the hip joint, etc.

Pre-operative preparations
  • Take blood test, hip and chest X-rays and electrocardiogram
  • Physiotherapy including muscle training and breathing exercises
  • No food or drink 6 hours before surgery
  • Cleansing of the area to be operated
  • If you have any medical condition like cardiac disease, hypertension, diabetes mellitus, anaemia, asthma, and so on, please consult your doctor for assessment and stabilize the condition before surgery.
  • It normally takes about 3 to 4 hours.

Pre-operative preparations
  • If your condition is stable, you are allowed to take some food 4 to 6 hours after surgery. You will be given intravenous fluid supplement or blood transfusion if necessary.
  • You will be given oral, intramuscular, intravenous or other forms of analgesics to control pain.
  • An abduction pillow will be placed between legs to prevent dislocation of the replaced hip.
  • The drains inserted in the surgical wound will be removed in 2 to 3 days after surgery.
  • Doctors usually inserted a urinary catheter prior to the surgery to bring comfort to the patient after surgery. The catheter will be removed in 2 to 3 days after surgery.
  • During the first 2 to 3 days after surgery, as recommended by the doctor, most patients can start walking and sitting. It is recommended to sit on a high chair to avoid too much flexion of the operated hip joint, and thus to prevent possible dislocation. Patients are also advised to use a toilet commode to avoid too much flexion of the hip joint.
  • Deep breathing and exercises for the feet and ankles are good to prevent lung infection and deep vein thrombosis.
  • You can resume standing and walking under supervision of the physiotherapist.
  • You may need to stay in the hospital for one to two weeks after surgery. You are recommended to visit the hospital to receive continuous physiotherapy training.

To prevent dislocation of the operated hip joint:

  • Do not cross legs
  • Do not bend down your body to pick up things
  • Do not sit on low chairs or sofa

Possible complications
The rate of serious complications following hip replacement surgery is low. Common ones are:
  • Deterioration of the pre-existing diseases like cardiac disease, hypertension, stroke, diabetes mellitus, etc.
  • Wound infection or delayed wound healing
  • Bleeding from the wound or haematoma formation
  • Deep vein thrombosis, pulmonary embolism, fat embolism
  • Dislocation of the replaced hip or infection
  • Loosening of the prosthetic joint
  • Nerve palsy
  • Prolonged bed rest leading to pressure sore, etc.