A Failed Or Worn-out Hip Replacement
When Your Joint might need a Second Chance
Failing hip replacements, also known as aseptic or mechanical failure, occurs when a previously implanted artificial hip joint no longer functions as intended. These situations can arise for various reasons, and it’s essential to recognise the signs and seek timely intervention to restore your comfort and mobility.
WHAT CAUSES A HIP REPLACEMENT TO FAIL?
The main reasons why a hip replacement may fail include:
Over time, the materials used in artificial hip joints, such as the bearing surfaces (metal, plastic, or ceramic), can undergo gradual wear and tear. This is a natural consequence of the daily stresses placed on the hip joint. As these materials degrade, they can lead to the development of instability, pain, and a reduction in overall functionality. Essentially, the gradual deterioration of the artificial joint components can mimic the degeneration seen in natural joints.
In some cases, the prosthetic components of the hip replacement may become loose or detach from the bone or the implant itself. This can be a result of several factors, including the body’s response to the implant, surgical technique, or mechanical issues. When these components loosen, they can cause significant pain and limit the patient’s range of motion and overall hip joint function.
Precise placement of the prosthetic components during the initial surgery is crucial for the long-term success of a hip replacement. Incorrect positioning, alignment, or sizing of the artificial components can lead to premature failure. This could involve components that are too large, too small, or improperly aligned, affecting the hip’s biomechanics, and causing pain, discomfort, and instability.
A hip replacement can dislocate if the ball-and-socket components do not align correctly. This misalignment can lead to the artificial joint coming apart, causing significant pain and joint instability. Patients may experience difficulties with walking, standing, and general mobility.
Although rare, infections around the artificial hip joint can be a serious cause of implant failure. Infections may develop due to contamination during surgery or can occur post-operatively if proper sterile techniques and post-operative wound care are not followed. Infections lead to inflammation, pain, and potential failure of the implant. In severe cases, the implant may need to be removed entirely to control the infection.
Fractures around the hip joint can compromise the stability of the implant. These fractures may result from trauma or accidental falls, which can be especially concerning for elderly patients or those with weakened bones. When fractures occur, the implant may become dislodged or damaged, necessitating revision surgery.
Although uncommon, fractures of the implant components can occur. This can happen due to the accumulated stress and forces the implant endures over time. Implant fractures can lead to component separation and the failure of the artificial hip joint, requiring revision surgery to address the damage.
Some hip implants use metal components. In these cases, friction between metal parts can release metal ions into the bloodstream, potentially leading to complications. This includes adverse local tissue reactions, metallosis (metal toxicity), and soft tissue damage. These complications can ultimately lead to implant failure, prompting the need for revision surgery to remove and replace the problematic implant. It’s important to monitor metal-on-metal hip replacements closely for any signs of adverse reactions or complications.
HOW A WORN-OUT OR FAILING HIP REPLACEMENT IS DIAGNOSED
When you consult with Dr Keeley about concerns regarding your hip replacement, he will conduct a thorough review of your medical history, overall health, prior surgeries, and current medications. A detailed account of your symptoms, including their onset, duration, and any activities that worsen or relieve them, is crucial for an accurate diagnosis.
Dr Keeley will discuss your symptoms in detail, focusing on the location, intensity, and nature of your pain, as well as how it impacts your daily life and activities.
A comprehensive physical examination of your hip will be performed to assess range of motion, strength, stability, and any tenderness or discomfort. Specialised tests may also be conducted to identify the source of your symptoms.
To further evaluate your failing hip replacement, Dr Keeley may recommend:
X-rays: To check for implant-related issues like component wear or loosening.
MRI: To assess soft tissues and detect fluid accumulation, inflammation, or implant instability.
CT Scan: For detailed cross-sectional images of the hip joint, evaluating implant positioning and structural integrity.
Ultrasound: To evaluate soft tissue conditions and identify fluid collections.
Blood Tests:Blood tests may be performed to check for inflammatory markers or infections that could be contributing to the implant failure.
Joint Aspiration (Arthrocentesis):In some cases, Dr Keeley may remove synovial fluid from the hip joint for analysis to determine if infection or inflammation is present.
If needed, Dr Keeley may refer you to other specialists, such as infectious disease experts or rheumatologists, for a more comprehensive evaluation.
These diagnostic methods are tailored to your specific symptoms, helping Dr Keeley to accurately diagnose the cause of your failing hip replacement and develop an effective treatment plan for you.
TREATMENT OPTIONS FOR A FAILING HIP REPLACEMENT
Following are the most common treatment options for a failing hip replacement:
In some cases, initial treatment may involve medication to manage pain, inflammation, or infection. Non-steroidal anti-inflammatory drugs (NSAIDs) or antibiotics may be prescribed based on the specific condition causing the implant failure.
When a hip replacement demonstrates substantial implant wear and tear, component loosening, or other structural issues, revision hip replacement surgery is often necessary. During this procedure, Dr Keeley will remove the original prosthetic components and replace them with new ones. Revision surgery aims to restore joint stability and function, alleviate pain, and extend the longevity of the implant.
If the implant failure is due to infection, the primary focus is on treating the infection. This involves the removal of infected tissue, a thorough cleansing of the joint, and the administration of antibiotics. In some cases, a two-stage revision may be required, where the implant is temporarily removed and replaced after the infection has cleared.
In cases of inflammation-related implant failure, specific treatment strategies may be employed to address the inflammation and its underlying cause. This can include anti-inflammatory medications, physiotherapy, and lifestyle modifications.
If the implant’s failure is attributed to malpositioning during the initial surgery, a corrective procedure may be performed to reposition the components for improved stability and function.
When bone fractures around the hip joint contribute to implant instability, addressing the fractures may be necessary. This can involve surgical repair and may be combined with revision surgery if implant components have been compromised.
For patients with metal-on-metal hip replacements, Dr Keeley will carefully evaluate the levels of metal ions in the bloodstream and consider removing and replacing the implant if excessive metal ion release is detected. This is essential to prevent further complications associated with metal toxicity.
Each patient’s case is unique, and the choice of treatment depends on the underlying cause of the implant failure and your individual health and lifestyle.