AMIS METHOD – MINIMALLY INVASIVE HIP REPLACEMENT SURGERY

In principle, the AMIS method can be used in all age groups and with any body constitution. However, the operation is more demanding for muscular men than for slim, petite women. This is because the muscles have to be kept aside during the operation. Even when replacing a loosened hip stem, the AMIS technique is my preferred surgical method. The only exception is when a very long, straight hip stem needs to be implanted. In this case, a different surgical approach is sometimes chosen because it is not always possible to insert long revision stems through a muscle gap. This is of course clarified with the client in advance.

The AMIS surgical method can be performed under both general and spinal anaesthesia. During spinal anaesthesia, the patient is awake, but the legs are anaesthetised so that there is no pain during the operation.

In principle, you can get up again on the day of the operation if this method is used.

The operated leg can be fully weight-beared immediately. For safety reasons, forearm crutches should be used for at least the first few days after the operation.

Normally, you can go home a few days after hip joint replacement using the AMIS method. Of course, this decision is made individually together with you as the patient, so that a shorter or longer stay in the clinic is also possible. Rooming-in is also an option at the ETHIANUM Heidelberg.

Inpatient rehabilitation is possible after minimally invasive implantation of a hip joint endoprosthesis using the AMIS technique, but is not necessary. From a medical point of view, normal outpatient physiotherapy is completely sufficient. As the patient, you decide whether you prefer inpatient rehabilitation or outpatient physiotherapy, for example in our physiotherapy practice.

In principle, you can drive a car again very soon after your AMIS hip replacement. For insurance reasons, however, it is advisable to wait about four weeks after the procedure.

That depends very much on your profession. Desk jobs can be resumed very quickly, usually within the first few weeks after the operation. Occupations that involve heavy physical labour require a longer break. A few months should be expected in this case. The reason: if the endoprosthesis is anchored in the bone without cement, the implant must first “grow into the bone”. If the operated hip is exposed to extreme loads during this phase, the ingrowth of the artificial hip joint may be disturbed.

Which sport is the question. Sports that involve movement of the joint without higher impact can be resumed shortly after the operation. Cycling, for example, is usually possible again just one week after the operation, but using the exercise bike first to be on the safe side.

As soon as the wound has healed after around two to three weeks, you can also go swimming again. Stop and go sports such as squash or volleyball are not ideal for the artificial – as well as for the natural – hip joint, as they can lead to faster wear and tear or earlier loosening of the endoprosthesis. In principle, however, almost all sports are possible again in the medium term.

The implants used today have an average service life of around twenty years. However, the service life of a prosthesis depends on many factors.

In principle, the poorer the bone quality and the more extreme the daily load on the hip, the higher the risk of a prosthesis loosening or wearing out over time. Septic loosening must be distinguished from this so-called aseptic loosening of an endoprosthesis. Septic loosening of an endoprosthesis is caused by a bacterial infection. Bacteria can reach the artificial joint via the bloodstream as a result of a dental infection, for example. Accordingly, particular caution is required in the case of infections, for example of the teeth, but also in other parts of the body (throat, nose, ear infections, infected wounds, etc.). In such cases, a doctor should always be consulted and antibiotic therapy should be carried out to protect the endoprosthesis.

Symptoms of a loosened hip joint endoprosthesis are pain, especially when exerting pressure, as well as an occasional feeling of instability in the hip. If the hip joint region is reddened, swollen and overheated or fever occurs, a bacterial infection may be present. In these cases, prompt diagnostics are essential to clarify the suspicion and cause of a loosening.

In the event of loosening without infection, the affected part of the prosthesis can be replaced in a single procedure. In many cases, this is also possible using the minimally invasive AMIS technique. If a bacterial infection is found to be the cause of the loosening of the endoprosthesis, more than one procedure is often necessary in addition to antibiotic therapy in order to first treat the infection and then implant the new endoprosthesis in the next step. Fortunately, however, septic endoprosthesis loosening occurs comparatively rarely.