AMIS approach for hip surgery

What exactly is the AMIS approach for hip surgeries?

The AMIS method describes a specific surgical approach for implanting an artificial hip joint. The abbreviation stands for Anterior Minimally Invasive Surgery.

The hip joint allows a great range of movement allowing us to turn, bend and stretch our legs in different directions. Due to the large range of motion, the joint can show signs of wear with age. This is known as osteoarthritis or, in the specific case of the hip, coxarthrosis.

When conservative treatments are no longer sufficient to improve the pain and limitations in movement, a hip joint prosthesis, or total hip arthroplasty (THA), may be a viable option.

To reach the hip joint during this operation, the surgeon can choose different access routes. In the case of the AMIS method, the approach is from the front, allowing the artificial hip joint to be inserted as gently as possible.

When and for whom is the AMIS approach used in hip surgeries?

The AMIS approach can be considered as a surgical technique for many patients. This includes very muscular or overweight patients as well as patients with previous illnesses.

Muscular patients benefit in particular from the fact that the muscles and supplying nerves are spared. Overweight patients benefit from the fact that their mobility is restored relatively early.

Patients with many pre-existing conditions also benefit from this, as does the fact that the risk of major bleeding is minimized.

The AMIS approach is used for patients who are receiving their first hip joint prosthesis. In cases of prosthesis revision, for example, when the hip replacement has become loosened over time, other surgical methods are generally preferred.

What is the process of a hip surgery?

Different materials and surgical techniques are used when implanting a hip joint prosthesis. Nevertheless, the basic procedure is always very similar.

The hip joint consists of a femoral head, which is located on the thigh bone (femur), and a socket which is also called the acetabulum and is located on the bony pelvis. The femoral head and acetabulum are each covered by articular cartilage and virtually interlock. Various strong muscles and ligaments stabilize the hip joint and enable the various movements.

The most common indication for the implantation of an artificial hip joint is osteoarthritis. In this condition, the mass of the joint cartilage gradually decreases due to long-term stress, meaning that the joint head and socket eventually rub against each other at an advanced stage. This causes severe pain and restricted movement for those affected.

If the symptoms can no longer be relieved without surgery, an artificial joint can be implanted.

During the operation, the hip joint is first exposed and the surrounding muscles are held aside with the help of hooks. The femoral head is then released from the socket, which is medically referred to as dislocation.

At the end of the femur near the hip joint, the femoral head is completely removed. The acetabulum is usually slightly widened.

A synthetic socket is then implanted into this bony structure of the pelvic bone. A so-called stem is inserted into the femur. This is a long rod with an artificial joint head at the end, which then fits into the artificial socket.

At the end of the surgery, the joint head and socket are brought back together, the muscles that were held aside are released, and the surgical wound is closed.

A distinction is made between a cemented and a cementless endoprosthesis. In other words, cement is either used to secure the prosthetic components, or it is not. Both methods have various advantages and disadvantages and must be carefully weighed against each other before surgery.

How does the AMIS approach work? 

The AMIS method can be used with different materials and types of prosthesis. The special feature is that an anterior approach is chosen, which utilizes a natural muscle gap.

This surgical technique requires the use of a special positioning table and specific instruments. This way, the patient is positioned so that a relatively small skin incision is sufficient to allow a complete view of the surgical area and insertion of the artificial hip joint.

The implantation of the joint itself basically follows the same procedure as other surgical techniques for installing a total hip replacement.

Risks and benefits of the AMIS approach

The advantage of the AMIS approach for hip replacements is the particular surgical route allows muscles, nerves and soft tissue to be spared.

The anterior hip muscles form a natural muscle gap through which the various surgical instruments are inserted into the joint. In contrast to other approaches, such as from the side or back, the muscles are only held to the side and do not have to be cut or excessively stretched. This usually enables patients to stand up again on the day of the operation.

Furthermore, the use of this muscle gap minimizes the likelihood of injury to the nerves that supply the hip muscles. This not only prevents possible consequential damage from the operation, but also reduces pain after the operation.

The AMIS approach also offers the possibility of only making a small incision in the skin, so that the soft tissue can be spared and the risk of bleeding minimized. This is particularly beneficial for patients with pre-existing conditions.

The risks of surgery using the AMIS method do not differ from the risks associated with conventional techniques. As with any operation, there is a risk of damaging nerves or muscles.

However, the surgeon's experience with this method and special equipment in the operating room minimizes this risk as much as possible.

Who covers the costs of hip surgery? 

If there is a medical indication for a hip joint replacement, the costs are covered by statutory health insurance. This usually includes the costs for the AMIS surgical approach.

This also applies to private health insurance companies in most situations.

The amount of costs reimbursed in a specific case can be obtained individually from the respective health insurance company.

What should patients be aware of after hip surgery? 

A hip replacement is performed as part of an inpatient hospital stay. This is generally followed by rehabilitation.

Directly after the operation, the corresponding leg is placed in a special splint. Thanks to the continuous development and improvement of surgical techniques, patients are mobilized again as quickly as possible and are usually able to stand within the first 24 hours after the operation.

To prevent the formation of a thrombosis, the patient will receive daily injections of a blood thinner for the period of restricted mobility, and if necessary, this can be administered by the patient on their own.

Post-operative follow-up treatment can vary between the different surgical methods and hospitals.

In every case, the most important goals are to allow the hip joint to bear weight as quickly as possible and to ensure that the patient is free of pain.

During the rehabilitation program and during the first few months after the operation, the patient receives regular physiotherapy in which the muscles are constantly trained, and the hip joint is stabilized.

Depending on the patient's need for security and external circumstances, crutches are required for a period of around two weeks. During this period, the patient's gait has usually stabilized to such an extent that free walking is possible.

To assess the surgical outcome, x-tays oft he hip joint are taken at regular intervals after the surgery. This can usually be done without any issues by a local orthopedic specialist or surgeon.

Which doctors & clinics specialize in the AMIS approach for hip surgeries?

The implantation of an artificial hip joint represents a major change in the patient's life. That's why the surgeon should be chosen carefully in order to achieve the best possible result.

The ability of a surgeon to perform the AMIS method depends largely on their experience and the number of procedures they have performed. We have therefore carefully checked the experience of all the specialists listed here and found them to be competent and capable.

Take the opportunity and contact one of our experts directly to arrange an initial consultation.

Anyone in need of a doctor would expect the best possible medical care for themselves. Therefore, patients are looking for the most suitable clinic for their needs. Since this is not an objective decision and a respectable doctor would refrain from claiming to be the best, patients must trust the experience of a doctor.

We can help you find an appropriate expert for your condition. All the doctors and clinics listed have undergone extensive review and have been verified by us for their outstanding expertise in the AMIS approach for hip surgeries. They are looking forward to and are ready to address your questions and treatment requests.