The following document is provided to all patients before surgery. You may
read it below,
download a Microsoft Word version or
download an Adobe Acrobat Reader version.
You may need to install the free
Adobe Acrobat Reader in order to
view/print this document. Click the logo here and then on the Adobe
website to download the software.
DR. ARNO SMIT, M.D., F.R.C.S.(C)
ORTHOPAEDIC SURGERY Unit 44 - 1480 Foster Street
White Rock, B.C. V4B 3X7
Phone: (604) 538-0068
Fax: (604) 538-0703
You are scheduled for total knee replacement. This document
summarizes the discussion that you and I had about the benefits and risks
associated with this procedure. Please read this document carefully, then
acknowledge your understanding and agreement by initialling on the line
provided before the various points. This will help ensure that you fully
understand the implications of the decision to undergo this operation.
Please review the following points:
1/ Purpose of operation. The primary purpose of this procedure
is relief of pain. Secondary purpose of this procedure is to enhance walking
ability. Tertiary purpose is to restore anatomy as closely to normal as
possible. The prosthesis is designed for walking, even brisk walking. It is not
designed to allow running etc.
2/ Risks of operation. It is not difficult to see how this
operation may be beneficial to you. However, all of surgery carries inherent
risks. Risks pertinent to this operation include the following:
-Risk of anesthesia, general or spinal anesthetic. You will
have the opportunity to discuss this further with the anesthesiologist.
-Risk of infection. The infection risk
is approximately 1:50 to 1:100. Superficial infection can be managed by
antibiotics, and/or washout of the wound and surgical site. On occasion, the
prosthesis will become infected. In this scenario, removal of the prosthesis,
temporary placement of an antibiotic loaded spacer, and definitive placement of
a new prosthesis after approximately two or three months would be necessary.
This is a very grave complication, and is fortunately rather rare. Surgery to
replace an infected prosthesis would normally be carried out in a university
hospital. Extremely rarely, the infection cannot be controlled and a definitive
prosthesis cannot be placed. This may lead to a ‘flail knee’, knee fusion
(‘stiff leg’) or even amputation. Death from uncontrolled infection is
extremely rare, but possible. The risk of infection is increased in the
presence of smoking, diabetes, rheumatoid arthritis, and other conditions
affecting the immune system. Of note, late infection can occur when bacteria
circulate in the bloodstream, In situations such as invasive dental work,
urology/gynecology procedures, bowel procedures etc.. If possible, a discussion
with the treating practitioner regarding the need for protective antibiotics
should be carried out prior to performing these procedures.
-Injury to the neurovascular structures. Important nerves and
blood vessels are located around the surgical site. Great care is taken
throughout the operation to avoid damage to these structures. However, on
occasion damage to nerves can occur, possibly leading to numbness an/or
weakness, possibly paralysis. This is very rare. Damage to the blood vessels is
very rare as well. However, such injury could lead to rapid blood loss, and may
lead to blood transfusion during surgery. As well, vascular repair could be
necessary, ordinarily performed by a vascular surgeon on an emergent basis.
This would require emergency transfer to a hospital providing vascular surgery.
Fortunately, major vascular injury is extremely rare.
-Deep venous thrombosis/pulmonary embolism and the need for anticoagulation.
This operation can lead to development of a blood clot in the deep veins of the
operated and/or non-operated leg. This impairs the circulation in the legs.
Furthermore, parts of this blood clot can be released into the bloodstream,
these can reach the heart and lungs and cause severe shortness of breath, even
sudden death. In order to minimize this risk, you will be asked to start
walking as soon as possible after the surgery. You will receive a blood
thinner, low molecular weight heparin, for approximately one week. It is my
preference that this is followed by another five weeks of aspirin use, 325 mg
per day. As well, if tolerated, the compression stockings that will be provided
to you in the hospital, should be worn for a total of six weeks. Under these
circumstances, the risk of death from pulmonary embolism appears to be well
below one in thousand. On occasion, this régime is modified based on other
health concerns, which may necessitate assessment by a specialist in internal
medicine. If a blood clot develops in the legs, this may lead to prolonged
treatment with a blood thinner. If heart/lungs become involved, intensive care
treatment may be required. These complications would ordinarily be treated by
-Possibility of a blood transfusion. This operation will lead
to some blood loss. Usually, this is between 100 and 500 ml. Most often, blood
transfusion is not necessary. However, sometimes blood transfusion is offered
when a combination of sleep deprivation, pain medication and blood loss prevent
progression of the rehabilitation program. A blood transfusion my act as a
‘boost’, to allow mobilization, avoiding complications related to prolonged bed
rest, such as development of a blood clot, pneumonia, etc..
3/ Expected postoperative course.
-Mobilization after surgery is important to prevent
complications, and to resume independent self-care as soon as possible. The
degree of weight bearing that is allowed immediately after surgery is decided
upon by the surgeon during surgery, depending on the achieved firmness of the
fixation. With a non-cemented prosthesis, protected weight-bearing may be
necessary for approximately six weeks, to allow on-growth of bone onto the
prosthesis, leading to secure long-term fixation, without compromise of the
position of the prosthesis.
-Hospital stay is dependent on achieving pain control through
medication by mouth, as well as achieving safe, independent, mobilization.
Depending on circumstances, this usually means 1-5 days of hospital stay. Home
care nursing is available within the first week, to ensure that the blood
thinner régime is completed, and that no untoward complications occur. Dressing
changes will be performed as necessary.
-Physiotherapy starts immediately after the operation while in
hospital. This is continued in the outpatient department after discharge from
hospital. Most often, the final range of motion achieved is similar to the
range of motion prior to surgery.
Usually, arrangements for staple removal are made at the two-week mark, in the
daycare department of Peace Arch hospital after a physiotherapy appointment.
-I explained that, initially, residual discomfort and swelling are common.
Numbness may be present around the knee. These issues usually settle in
approximately six months, occasionally a year. Rarely, these can persist.
Through use of less invasive surgery, I attempt to minimize residual pain from
disrupted soft tissues.
- Further standard follow-up will be at 8 weeks, 6 months, and one year. After
this, yearly follow-up with X-rays is recommended, to allow early detection of
possible problems with the prosthesis.
If after reading this, you fully understand the issues and wish to proceed, your
signature on this document will confirm the previously obtained consent for
surgery and blood transfusion.
Arno Smit, M.D., F.R.C.S.C.