Additional Information on Hip and Knee Surgery
"This website and the general handout I provide in the office will outline all the general principles of hip and knee replacement surgery, the realistic outcomes and things you need to be aware of. This handout provides extra information that you may find useful."
Before surgery you will need to attend a pre-admission clinic at the hospital where you will meet a clinical nurse who will go over the basic admission process and post operative course. In addition there are routine pre-operative blood tests and an ECG that are performed. Occasionally a chest X-ray is needed.
If any significant abnormality is detected in your pre-operative visit, the appropriate action/referral will occur to investigate and treat any issue needing attention.
If you see a cardiologist routinely and are on a regular blood thinner, please advise your cardiologist you are having a joint replacement and that you need to stop blood thinners such as warfarin, plavix/clopidigrol and aspirin. I am happy to perform the replacement under low dose aspirin (100mg) if your cardiologist insists.
Medication You Need To Stop
Please stop all anti-inflamatories (mobic, celebrex, nurofen, voltaren etc ) 1 week before surgery.
Herbal medication (fish oils, garlic, echinacea, kava, glucosamine etc ) need to be stopped 1 week before surgery as they can cause excessive bleeding.
If you are diabetic it is important that your diabetes is under proper control. Your GP will usually see to this. Dental issues. If you have any major dental issues requiring attention please get this done before your joint replacement.
If you have any prostate issues (Males), please inform me as every patient needs a urinary catheter for 24-48 hrs and prostate problems can result in a difficult catheterisation therefore it is best to have a urologist consult if need be.
Antiseptic Shower Soap
You will be given an antiseptic soap at the pre-admission clinic that you need to shower with for the 2 days prior to surgery. This will reduce the risk of a skin infection after surgery.
Please DO NOT shave hair around the hip or knee before surgery. The hospital nursing staff will shave the area if needed using special clippers that do not cut the skin.
The surgery is usually carried out under a combined spinal anaesthetic and light general / sedation. Spinal anaesthesia is safe and has been shown to assist in reducing complications during joint replacement surgery. It provides excellent post operative pain relief. The Anaesthetist will discuss this with you in detail.
A urinary catheter is used in all cases. Patients with a spinal as well as those who don't have a spinal but get morphine for pain relief, will invariably have difficulty passing urine for 12-18 hrs and hence the need for a catheter. It is much easier to pass a urinary catheter when you are sedated just before surgery than to pass a catheter when you are awake on the ward with a full bladder.
Removing a catheter is a very easy process done by the ward nurses and is not painful at all.
Antibiotics are given intravenously for 24-36 hrs and your IV cannula will remain in your arm for this period. The cannula is also often attached to a PCA machine which allows you to administer pain killers when needed. I do not use a PCA in all patients as often (such as in the minimally invasive hip approach) the local anaesthetic and oral pain tablets are sufficient.
You will be given the appropriate pain relief regime that the anaesthetist will order. This regime is tailored to each individual's needs.
The key to preventing thrombosis is mobilisation and exercise . Every patient is fitted with a calf compressor after surgery. This machine compresses the calf intermittently which promotes venous blood flow back to the heart and prevents clots. The compressors are used whilst in bed for the first 48 hrs. The sooner you get out of bed and walk the less the risk of a thrombosis.
In addition to early mobilisation and calf compressors you will either be given oral aspirin or clexane injections to assist in reducing the incidence of thrombosis.
I encourage 2 walks a day whilst in hospital. The more you can manage the better but don't overdo things.
Whilst the risk of a thrombosis is low despite all preventative measures they can still occur and are treated accordingly. I do not perform a routine Doppler scan to check for thrombosis as all studies have shown that routine scanning is a waist of time.
Antibiotic Policy For Procedures Following Joint Replacement
The risk of getting an infection in your replaced joint is extremely rare following routine procedures such as dental work and colonoscopies.
- Dental procedures: For routine dental cleaning after joint replacement surgery there is no need to take antibiotic prophylaxis. For major dental work after a joint replacement ( such as root canal etc) I recommend a single dose of 2gm amoxicillin 1 hour before provided you are not allergic to amoxil.
- Colonoscopy, Prostate, Bladder or Gynaecological procedures after joint replacement: Routine colonoscopy without any major biopsies or risk of bleeding do not require prophylactic antibiotic cover.
Surgery to the bladder, bowel, gynaecological and prostate surgery require a single intravenous antibiotic dose that is administered by the surgeon at the time of the procedure. Please advise them that you have a joint replacement.
Some other things about replacements:
All knee replacements have some numbness on the outer side of the wound. This is unavoidable as there is a skin nerve that goes directly across the skin incision and hence is purposefully cut in order to open up the knee joint. It is a minor nerve and the numbness will tend to lighten up over time but is never completely eliminated.
All knee replacements click. This is normal. It is simply the metal and polyethylene parts touching each other and is no cause for alarm. It is how the joint functions. The clicking noise will tend to get quieter over time.
Hip Replacements can occasionally click at the extreme of motion. No cause for alarm. Some ceramic on ceramic hip bearings can squeak (rare) again no cause for alarm.
Intraoperative stability is important in hip replacements. Rarely one may need to tension the hip which can lead to a leg length discrepancy. Various techniques are used to minimise this possibility.
The key to a successful recovery is motivation to mobilise and to do the exercises the physiotherapist will show you. Hip and Knee replacement surgeries have excellent outcomes provided the patients assist in a motivated recovery.