The implantation of an artificial hip joint, also known as total hip replacement (THR), is one of the most successful surgeries in modern orthopedics. Various methods are available for anchoring the prosthesis: cemented and cementless fixation. Both techniques have specific advantages and disadvantages that should be weighed according to individual patient conditions.

In this article, the two procedures are comprehensively presented, their respective areas of application are discussed and important decision-making criteria are explained. The aim is to provide a sound basis for decision-making for patients and physicians.

2. Anatomical basics of the hip joint

The hip joint is one of the largest and most stressed joints in the human body. It consists of the spherical femoral head (caput femoris) and the socket (acetabulum) in the pelvis. A complex interplay of cartilage, ligaments, muscles, and synovial fluid ensures stability and smooth movement.

Wear and tear phenomena such as osteoarthritis lead to pain, movement restrictions and ultimately to the need for joint replacement.

3. History and Development of Hip Replacement

Modern hip arthroplasty has a long history of development. The first attempts with artificial joints date back to the early 20th century. In the 1960s, Sir John Charnley revolutionized endoprosthetics with the introduction of the cemented prosthesis stem. Later, cement-free models were developed that enable biological integration of the implant into the bone.

Today, the most modern materials and techniques are available, which have significantly improved the durability and functionality of the prostheses.

4. Cemented Hip Replacement

4.1 Procedure and Technique

In cemented hip replacement, the prosthetic stem is fixed in the femur with bone cement. The cement (polymethylmethacrylate, PMMA) hardens within minutes, creating a load-bearing connection between the implant and bone.

4.2 Advantages of cemented hip prosthesis

• Immediate load-bearing capacity: The prosthesis can be fully loaded directly after the operation.
• Suitable for osteoporosis: In cases of soft or porous bone, cement fixation provides a stable anchorage.
• Less risk of fracture: No need to press the implant firmly into the bone, which can avoid fractures.

4.3 Disadvantages of cemented hip prosthesis

• Revisions are more difficult: Removing a cemented prosthesis is complex and can cause bone loss.
• Possible cement reactions: In rare cases, cement allergies or cement embolisms can occur.

4.4 Indications for cemented hip prosthesis

• Older patients with reduced bone quality
• Patients with osteoporosis
• Individuals with limited mobility

5. Cementless Hip Replacement

5.1 Procedure and Technique

In the cementless technique, the implant is connected to the bone through a specially coated surface. This porous structure promotes the ingrowth of bone and ensures a stable, biological fixation.

5.2 Advantages of cementless hip prosthesis

• Longer durability: The biological integration can provide a more stable long-term anchorage.
• Easier revision surgeries: No cement that needs to be removed.
• No cement complications: No risk of cement fracture or embolism.

5.3 Disadvantages of Cementless Hip Prosthesis

• Delayed load-bearing capacity: The full load-bearing capacity is only achieved after several weeks.
• Higher risk of fracture during surgery: The press-fit implantation can weaken the bone.

5.4 Indications for Cementless Hip Prosthesis

• Younger, active patients
• Good bone quality
• Patients with high physical demands

6. Hybrid technique

A combination of both methods is the so-called hybrid technique. For example, the acetabular cup is implanted without cement, while the stem is cemented. This technique can combine the advantages of both methods.

7. Decision criteria: When cementless, when cemented?

The choice between cemented and cementless hip replacement depends on several factors:

• Age: Younger patients often receive cementless prostheses.
• Bone quality: Osteoporosis tends to favor a cemented prosthesis.
• Activity level: Athletic individuals often benefit from cement-free models.
• Diseases: Certain pre-existing conditions may require a cemented fixation.

8. Rehabilitation and Follow-up Care

The correct aftercare plays a crucial role in the success of the prosthesis. Physiotherapy, targeted strengthening exercises and a gradual increase in load are essential for optimal function of the new joint.

9. Conclusion: The choice between a cement-free or cemented hip replacement is individual!

Both methods have their justification and should be tailored to the patient individually. The cemented fixation offers immediate stability, while the cementless variant enables long-term biological integration. A detailed consultation with the treating hip specialist is essential to make the best decision.