Hip replacement

Brief information

Surgical term:
(Total) hip joint endoprosthesis, THE, THR.

When is this procedure indicated?
If wear and tear of the hip joint occurs that can no longer be treated conservatively, causes severe pain on exercise and at rest and markedly restricts the patient's everyday activities, the hip joint can be replaced surgically with a prosthesis in order to reduce pain and improve the joint's function. Sometimes, when elderly people fracture a bone near the hip, it may be necessary to replace the entire hip joint.

Surgical technique:
Under partial or full anaesthesia, the hip joint is exposed and the head of the femur and the surface of the articular cavity are removed. An acetabular cup that fits perfectly into the joint and a prosthetic stem complete with an artificial femoral head are then inserted. The prostheses can then be secured in place with or without bone cement.

Inpatient stay:
patients are required to stay in hospital for around 12 - 14 days.

Follow-up treatment:
Immediately after the operation, movement exercises are commenced with walking aids. Normally, a period of convalescence and recovery in a specialist facility follows the inpatient stay.
By the 5th or 6th week, complete and independent weight-bearing should be possible.

In-depth information

After the knee joint, the hip joint is the largest joint in the human body. It is a ball-and-socket joint that is reinforced with powerful ligaments and the muscles that support the legs and pelvis. Its function is crucial for upright walking and the unrestricted mobility of the leg on that side. Over the years, the cartilage around the joint gets naturally worn and can progress to a stage at which severe pain occurs on exertion and there is considerable limitation of the joint's mobility. This is known as hip arthrosis or coxarthrosis.
Generally, there is severe extensive wear and tear of the joint surfaces. First, the cartilage is affected, and later the underlying bone of the femoral head and the articular cavity.
This frictional wear causes inflammatory reactions and gliding disturbances in the joint, leading to pain on exertion and sometimes even at rest, as well as increasing restriction of the joint's mobility.
The reasons behind this wear and tear process are partly due to the general ageing process or adverse mechanical stresses on the joint. These latter are primarily caused by excessive weight stresses (being overweight) and malformations of the articular cavity (too small or distorted), the femoral head (deformation of the head) or adverse positioning of the femoral neck (coxa vara / valga), causing an incorrect distribution of pressure within the joint. These malformations are often caused by the hip joint not maturing or developing properly during childhood (hip dysplasia).
Unequal load distribution caused by professional activities involving extreme physical work, or metabolic conditions such as after many years of cortisone therapy or circulatory problems, can also cause these types of malformation.
Injuries with direct (cartilage/bone injuries such as in cases of a femoral neck fracture) or indirect (capsule / ligament / tendon injuries) joint involvement can encourage the development of arthrosis.
Hip replacements, just like the human hip, are made up of two main components, the artificial articular cavity and the prosthetic stem with the ball-shaped prosthetic head. The parts of the prosthesis itself are made from special, very high-quality metal alloys. With cement-free prostheses, the parts that contact the bone are made from titanium.

When is a hip replacement indicated?
If worsening wear and tear of the hip joint causes severe restriction of the hip joint's mobility due to pain and limits the patient's general mobility, the insertion of a hip prosthesis is indicated to improve mobility and restore the patient's ability to walk without pain.

How is the surgery performed?

The surgery is performed under partial or full anaesthesia. A lateral incision is made to expose the hip joint and the diseased head of the hip joint is removed as planned prior to the operation. The articular cavity and femoral stem are then prepared using specialist instruments. Test prosthetic parts are then inserted to check the expected outcome. Only then are the final prosthetic components inserted and anchored stably into place. Depending on the stability of the bone, the patient's age and other contributory factors, this is done either without cement or by using a special bone cement.
Once wound drains have been inserted, the surgical wound is closed up anatomically.

A distinction is currently made between three different types of implantation and fixation procedure for hip joint replacements.

  1. With the uncemented form, both parts of the prosthesis are secured in place without cement.
  2. With the cemented form, both parts of the prosthesis are secured in place with cement.
  3. With the hybrid form, the prosthetic stem is secured in the femoral bone shaft with bone cement, however the artificial articular cavity is secured without it.

How long will I have to stay in hospital for?
The inpatient stay after the operation is around 2 weeks. The pre-operative checks can normally be carried out as an outpatient.

What follow-up treatment will I require?
On the very first day after the surgery, physiotherapy exercises are started. Passive movements on mobile rails and active strengthening exercises are combined to suit each individual. In addition to this, patients are helped to walk again with crutches and later helped to climb stairs.
Following inpatient treatment there is generally a period of rehabilitation which may be organised as an outpatient or at an inpatient facility, depending on the patient's needs and their agreement with their health insurance provider.