The Hip

Dear patient

The hip joint is of utmost importance for our mobility. Once the hip hurts mobility and the quality of life are impaired.

Total hip arthroplasty restores pain-free mobility and enables you of enjoying life again.

My long term follow-up studies of uncemented total hip replacement were published in the world’s leading scientific journals.

In the near future the differences in the anatomy of the male and the female pelvis will be taken into consideration. With these differences in mind I have already developed the Zweymueller SL offset-stem in cooperation with the manufacturer.

The following pages are meant to give you a better insight in the medical aspects of total hip arthroplasty: However, they should not prevent you from making an appointment with your doctor. I am at your disposal at any time that you would like to talk to me personally.

Yours

Alexander Grübl, MD
Orthopaedic Surgeon
 

How does the hip joint function?

The hip joint is a ball and socket joint. It joins the trunk to the legs. The hip socket is part of the pelvis. The hip head is the top part of the femur (thigh). Both (socket and head) are covered with articular cartilage that serves as a shock absorber. The joint is enclosed by a capsule. It’s inner layer produces synovia that reduces friction and nurishes the cartilage.

What causes the damage to the hip joint ?

Hip related pain is most frequently caused by the degeneration (degradation) (wear and tear) of the joint cartilage (arthritis). Disorders of growth, congenital hip dysplasia, traumatic lesions of the hip joint or chronic rheumatoid arthritis account for the degeneration. Often the cause is unknown.

Circulatory disorders of the hip (avascular necrosis of the head, AVN) can also necessitate total hip arthroplasty.

The abrasion of the joint cartilage leads to the malformation of the joint which in itself brings about marked pain and reduced mobility. The pain at first is felt with activity and later already in a state of rest.

What does an artificial hip joint look like?

The artificial hip joint consists of a cup, a head and a femoral stem. It replaces the degenerated hip joint and will permanently relieve the patient of his hip pain.

The artificial hip joint is made of different materials. In Austria titanium alloy is mainly used for the cup and the stem because of it’s specific strength and biocompatibility. Generally those prostheses are implanted without cement.
(E.g. Zweymüller – Prosthesis, see www.alloclassic.com).

The head is usually made of ceramics (aluminium-oxide) or metal (cobalt–chromium) and paired with ultra-high molecular weight polyethylene which offers excellent friction characteristics. Metal-on-Metal or Ceramic-on-Ceramic articulations are used for younger patients.

What different types of implants for my joint replacement are available?

In most cases total hip arthroplasty (total hip replacement) has to be performed.

In the case of a hemiarthroplasty the acetabulum (socket of the hip joint) is not replaced. The artificial ball head glides in the patient’s own acetabulum. This type of endoprothesis is used in cases of femoral neck fracture, provided that the cartilage inside the acetabulum is still intact.

When is the appropriate point of time to undergo surgery?

It is the patient who decides when the appropriate point of time has arrived.

Ordinarily I advise surgery if the patient suffers from a certain amount of pain that he or she finds hard to tolerate and/or the patient’s quality of life is impaired.

There is nothing like too young or too old the crucial point is how much you suffer. As a rule of the thumb, however, I would advise not to wait too long. It is always better to have surgery when your general state of health is still good.

What happens during surgery?

By way of minimally invasive surgery the surgeon approaches the hip joint and the endoprosthesis is implanted.

The operation usually takes one hour. You can choose between general anaesthesia or spinal anaesthesia. The anaesthetist will tell you what form of anaesthesia is best for you.

Of course as with all other operations there is also a certain risk in the case of getting a hip implant. Here mainly infection, thrombosis and emboli (venous congestion, reduced blood flow in the venous system and pulmonary infarcts) should be mentioned. Blood vessels or nerves could also be injured. In order to minimize these risks you will be given antibiotics before and .after surgery. The operating team will be wearing “space-suits” to minimize the risk of infection. You will receive injections to prevent thromboembolism from the evening preceding the day of surgery to the day you will no longer have to wear crutches.

How do I regain mobility?

You will be allowed to get out of bed on the first day after the operation. This is done to avoid complications and speeds up the healing process. You will relearn everyday movements like getting out of bed, sitting down or walking the stairs.

To improve your ability to move intensive physiotherapy will help build up your muscle strength. The success of hip surgery depends to a large extent on how well you cooperate at this stage.

It will take six to eight weeks for your muscles to regain as much strength as to safeguard your joint against unruly movements. Before that time arrives you must take care not to carry out certain movements like crossing your legs or rotating your body from inside out or sitting in deep armchairs.

How can I picture my life with an artificial hip?

Modern artificial hip implants will last a number of decades.

You will soon recognize: Everyday life is back to normal. You will be able to resume doing sports, cycling swimming or hiking being ideally suited.

There is a saying that patients tend to “forget” their hip because it has become an integral part of their body.

Scientific literature: see “Introducing myself - publications“

www.jbjs.org