» In the operation theatre complex
Dr. Amyn Rajani
prefers to operate early in the morning, hence you will be wheeled in to operation theatre at about 7.45am.
The anaesthetist will evaluate you and make you comfortable. After which fuild drips will be started.
» During Anaesthesia:
We use a combination of spinal anaesthesia and femoral block for unilateral total knee replacement and a combination of spinal and epidural anesthesia for bilateral total knee replacement. You will be made to sit with your back facing the anaestheitst so that your back can be cleaned and draped before injecting the anesthetic.
Spinal anaestheisa given before surgery. As soon as spinal anaesthesia is given your limbs become numb and your are made to lie down.
Femoral Block :
Femoral block is being given in the operated limb after surgery. This is a very safe and effective way of managing post-operative pain. The catheter is connected to an electronic pump which continously provides pain relief to the operated limb over a period of 48 hrs.
Our teams of anaesthetists are very well trained and hence when the spinal and epidural injections are given in your back, you may feel minimum or no pain at all. The epidural catheter is left in the epidural space and is connected to a pump externally, which gives pain medications at regular intervals. The catheter is normally removed after 48 hrs. As soon as spinal and epidural anesthesia is given, your limbs become numb and your are made to lie down.
Combined spinal and epidural anaestheisa is being given for a bilateral knee replacement
» Catheterisation :
Urinary catheterisation is done to monitor the urinary ouput during the surgery as well as after the surgery. The catheter is removed at 48hrs after the surgery.
» Preparation of the limb before the surgery :
Inflatable cuff attached to an electronic tourniqet machine is applied to the thigh to prevent intra-operative bleeding by increasing the pressure. Limbs are then scrubbed thouroghly by an assistant surgeon, to prepare it for painting and drapping.
» Surgeons Preparation :
Before beginning to scrub the surgeon wears the body exhaust mechanism attached to a battery. This system is then covered with water impermeable hoods, so that no part of the surgeons body is exposed. This is an international protocol followed by all joint replacement surgeons.
After thorough scrubbing the surgeon is helped by the staff nurse to wear the hood gown and gloves. It is mandatory for all the assistants to wear the body exhaust mechanism or space suits and water impermeable gowns.
» Painting and Drapping :
The operated limb is then painted and draped according to the international protocol.
» The Surgery :
Before elevating the tourniquet pressure, an intravenous antibiotic is given to the patient by the anesthetist. A 10-15cm midline skin incision is made on the knee. The vastus medialis muscle is then divided and this division is extended distally to the medial patella retinaculum and medial side of the patella tendon. The knee joint is now exposed and the synovial fliud is removed by the suction. The patella along with the muscles is now moved to one side and the damaged tibial and femoral surfaces are exposed. The damaged surfaces of the femur, tibia and patella are removed with the help of a battery operated saw, using specialized jigs. The ligament balancing between the inner side (medial collateral ligament) and the outer side (lateral collateral ligament is now done. A Sizer is used to measure the exact size of the implant required for these cut surfaces.
A trial implant is then fitted to confirm the size. The knee joint is now bent and rotated to make sure it is stable and moves smoothly. The final implant of appropriate size is then unpacked from a sterile box. Biological cement is used to fix the implant on the cut surfaces of the femur, tibia and patella. The tourniquet is released so that active bleeders can be cauterized, to prevent a blood loss and or haematoma. A good wash is given by jet lavage before putting in a negative suction drain in the joint. The muscle and subcutaneous layers are approximated and sutured by dissolvable sutures. The skin is closed by metal clips. A thick wool and crepe bandage is applied to the knee and this stays in place for no more than 48 hours.