Posterior Approach Total Hip Replacement
The Posterior Approach is probably the most commonly used surgical approach used in Australia and Worldwide. It is an excellent surgical approach. It has a slightly different risk profile than the Direct Anterior Approach and neither surgical approach is ‘better’ or ‘worse’ than the other.
As the name implies the posterior approach involves entering the hip through its posterior aspect with opening of the fibrous hip capsule. It allows for excellent exposure of the hip socket and can be extended if more extensive exposure is required. I undertake all my Revision Total Hip Replacements via this approach as I feel it gives my superior exposure for this more complex work.
Why would a Posterior Approach be recommended?
I would recommend a Posterior Approach is used if you have complex anatomy, that may require additional exposure to the femur or the acetabulum as explained above. Likewise, very muscular or overweight patients are not always good candidates for the Direct Anterior approach and will be offered a posterior approach.
If I have a Posterior Approach would I have the same type of Total Hip Replacement?
The choice of implant is individualised as outlined in About Total Hip Replacement Because the risk of dislocation is slightly higher at 3% with the Posterior Approach compared with the Direct Anterior Approach at 1% I tend to use a different head (that is the ball part of the joint) in my Posterior Approach patients. I use what is called a Dual Mobility Head. The Dual Mobility Head is a French-designed hip prosthesis. The difference between Dual Mobility and other hip replacements is that in Dual Mobility the hip joint consists of two balls that are able to move one inside the other (hence the ‘Dual Mobility). This allows an excellent range of movement while allowing excellent stability, thereby reducing the chance that the hip joint could dislocate.
Associate Professor Harvie has extensive experience with dual mobility hip replacement technology and has published research in this field. Dual Mobility hip prostheses are of particular attraction when performing traditional approach hip replacement (e.g posterior approach), where the risk of dislocation of the hip may be a concern.
Dual mobility prostheses may also be indicated in patients who have had previous spinal surgery and have reduced mobility in their lumbar spine.
What are the Risks of the Posterior Approach?
As with any major surgical procedure, there are certain potential risks and complications involved with total hip replacement surgery.
The possible complications after total hip replacement include:
- Infection
- Dislocation
- Leg Length inequality
- Fracture of the femur or pelvis
- Injury to nerves or blood vessels. Specifically the Sciatic Nerve resulting in weakness in the foot/ankle.
- Formation of blood clots in the leg veins
- Hip prosthesis may wear out
- Failure to relieve pain
- Scar formation
- Pressure sores
Is my rehabilitation different if I have a Posterior Approach?
There is little evidence to show much difference in outcome after Total Hip Replacement performed by either the Posterior or Direct Anterior Approaches by 6-12 months post-surgery. Although the ‘destination’ may be the same, the rehabilitation ie the ‘journey’ is slightly different and this is due mainly to the slightly increased risk of dislocation with the Posterior Approach. Certain activities are known to pose increased dislocation risk.
Some common precautions to be taken include:
- Avoid combined movement of bending your hip and turning your foot inwards
- Keep a pillow between your legs while sleeping for 6 weeks
- Never cross your legs and bend your hips past a right angle (90)
- Avoid sitting on low chairs
- Being careful when getting into and out of cars
- Avoid bending down to pick up things; instead a grabber can be used to do so
- Use an elevated toilet seat
Our physiotherapy team will give you clear instructions with these activities and ensure you are happy prior to discharge.
What are the Risks and Complications?
As with any major surgery, there are potential risks involved. The decision to proceed with the surgery is made because the advantages of surgery outweigh the potential disadvantages. It is important that you are informed of these risks before the surgery takes place.
Complications can be medical (general) or local complications specific to the Knee. Medical complications include those of the anesthetic and your general well being. Almost any medical condition can occur so this list is not complete.
Complications include:
- Allergic reactions to medications
- Blood loss requiring transfusion with its low risk of disease transmission
- Heart attacks, strokes, kidney failure, pneumonia, bladder infections
- Complications from nerve blocks such as infection or nerve damage
- Serious medical problems can lead to ongoing health concerns, prolonged hospitalization or rarely death
Infection can occur with any operation. In the hip this can be superficial or deep. Infection rates are approximately 1%. If it occurs, it can be treated with antibiotics but may require further surgery. Very rarely your hip may need to be removed to eradicate infection.
These can form in the calf muscles and can travel to the lung (Pulmonary embolism). These can occasionally be serious and even life threatening. If you get calf pain or shortness of breath at any stage, you should notify your surgeon.
Ideally, your knee should bend beyond 115 degrees but on occasion, may not bend as well as expected. Sometimes manipulations are required. This means going to the operating room where the knee is bent for you while under anesthetic.
The plastic liner eventually wears out over time, usually over 10 to 15 years, and may need to be changed. Alternatively the remainder of your own knee may wear out requiring revision to a Total Knee Replacement.
Fractures or breaks can occur during surgery or afterwards if you fall. To repair these, you may require surgery.
The operation will always cut some skin nerves, so you will inevitably have some numbness around the wound. This does not affect the function of your joint. You can also get some aching around the scar. Vitamin E cream and massaging can help reduce this. Occasionally, you can get reactions to the sutures or a wound breakdown that may require antibiotics or rarely, further surgery.
The knee may look different than it was because it is put into the correct alignment to allow proper function.
Your leg will be restored to it’s original length as the deformity caused by wearing of the knee has been corrected.
There are a number of ligaments surrounding the knee. These ligaments can be torn during surgery or break or stretch out any time afterwards. Surgery may be required to correct this problem. This problem is minimised with Robotic Assistance.
Rarely these can be damaged at the time of surgery. If recognized they are repaired but a second operation may be required. Nerve damage can cause a loss of feeling or movement below the knee and can be permanent.
Discuss your concerns thoroughly with your Orthopaedic Surgeon prior to surgery.
Summary
Surgery is not a pleasant prospect for anyone, but for some people with arthritis, it could mean the difference between leading a normal life or putting up with a debilitating condition. Surgery can be regarded as part of your treatment plan it may help to restore function to your damaged joints as well as relieve pain. Surgery is only offered once non-operative treatment has failed. It is an important decision to make and ultimately it is an informed decision between you, your surgeon, family and GP. Although most people are extremely happy with their new knee, complications can occur and you must be aware of these prior to making a decision. If you are undecided, it is best to wait until you are sure this is the procedure for you.