What You Need to Know About Hip Prostheses for Hemiarthroplasty

What is Hemiarthroplasty?

Hemiarthroplasty, or partial hip replacement, is typically performed for displaced fractures of the femoral neck, especially in elderly patients who may not be ideal candidates for a total hip replacement due to health concerns. Instead of replacing the entire hip joint, the surgeon replaces only the femoral head, which articulates with the acetabulum (the cup-shaped part of the pelvis). This procedure helps to relieve pain, restore function, and allow patients to regain mobility.

While hemiarthroplasty can effectively treat fractures, the decision to perform it is based on factors like the patient's age, activity level, and overall health.

Why Use Hip Prostheses for Hemiarthroplasty?

Hip prostheses designed for hemiarthroplasty play a critical role in the success of the procedure. These implants are specifically designed to fit the anatomy of the femoral head and provide stability while maintaining the function of the hip joint. The primary goal is to reduce pain and improve the range of motion by replacing the damaged part of the joint with a prosthetic that mimics the natural movement of the hip.

The prosthesis must be durable and able to withstand the stresses placed on it throughout the patient’s daily activities. For elderly patients, the materials used in the prosthesis must also be bio-compatible and resistant to wear, as their bone quality may not be as strong as younger patients.

Materials Used in Hip Prostheses for Hemiarthroplasty

Hip prostheses for hemiarthroplasty are generally made from a combination of metals, ceramics, and plastics. The most commonly used materials are:

• Titanium Alloys: Titanium is known for its strength, light weight, and bio-compatibility. It is resistant to corrosion and is commonly used in both the femoral head and stem of the prosthesis.

• Cobalt-Chromium Alloys: Cobalt-chromium alloys are also frequently used for the femoral head due to their strength, wear resistance, and durability.

• Ceramics: Ceramics are often used in the femoral head for their smooth surface, which reduces friction and wear over time. They are particularly valuable in younger, more active patients but can be more brittle than metal implants.

• Polyethylene: The acetabular component of the prosthesis, where the femoral head fits, is often lined with a high-density polyethylene cup to reduce friction and provide a smooth surface for the femoral head to glide.

Each material has its own set of advantages and challenges, and surgeons must choose the appropriate combination based on the patient’s age, activity level, and overall health.

Types of Hip Prostheses for Hemiarthroplasty

Hip prostheses come in several variations, depending on the design and intended use:

• Unipolar Hip Prosthesis: In this type, the femoral head is a single, solid piece that articulates directly with the acetabulum. This is the most commonly used implant in hemiarthroplasty due to its simplicity and cost-effectiveness. However, unipolar prostheses are often associated with higher wear rates and are less commonly used in younger or more active patients. These include: Austin Moore and Thompson Hip Prosthesis implants.

• Bipolar Hip Prosthesis: The bipolar prosthesis is designed with a mobile inner bearing that allows the femoral head to rotate within a shell. This design helps reduce wear and offers improved range of motion compared to unipolar prostheses. Bipolar hip prostheses are often chosen for patients who have a more active lifestyle.

Choosing the Right Prosthesis for the Patient

The choice of prosthesis depends on several factors, including the patient’s age, activity level, and bone quality. Younger, more active patients may benefit from a bipolar prosthesis, which offers greater mobility and reduces the risk of wear. In contrast, elderly patients with lower activity levels and poorer bone quality may do well with a unipolar prosthesis.

Surgeons must also take into account the patient’s overall health, comorbidities, and life expectancy when selecting the appropriate prosthesis. For instance, patients who are not candidates for total hip replacement due to other medical conditions may still benefit from a hemiarthroplasty with a well-designed prosthesis that offers both pain relief and mobility restoration. Jani's Bonecare provides comprehensive range of hip prosthesis implants, as well as instruments and instrument sets, to suit all requirements.

Surgical Considerations

Hemiarthroplasty is generally performed through a lateral or anterolateral approach, where the surgeon gains access to the hip joint by making an incision along the side of the hip. After the femoral head is removed, the appropriate prosthesis is inserted and secured in place using a stem that fits into the femoral canal.

The surgical technique plays a significant role in the overall success of the procedure. Proper alignment of the prosthesis and ensuring that the components are stable are essential for achieving long-term outcomes.

The Role of Jani's Bonecare in Hemiarthroplasty

Jani's Bonecare Co. Ltd., based in Kampala, Uganda, has been a trusted supplier of orthopedic implants and instruments since 2006. Our commitment to quality ensures that orthopedic surgeons have access to top-tier prostheses and surgical tools for procedures like hemiarthroplasty.

Jani's Bonecare offers a wide range of hip prostheses designed for hemiarthroplasty, including both unipolar and bipolar designs. These implants are made from advanced materials, ensuring durability and bio-compatibility. Jani’s Bonecare prostheses provide orthopedic surgeons with reliable, high-quality options that can improve the long-term success of surgeries and patient satisfaction.

In addition to providing prostheses, Jani's Bonecare also supplies a comprehensive range of orthopedic instruments, including reamers, drills, and alignment guides, to help ensure accurate and efficient surgeries. Surgeons trust Jani's Bonecare to provide the right tools to achieve the best results for their patients.