A hip replacement is a common surgery that can dramatically improve quality of life for those suffering from hip arthritis and pain. Over 300,000 total hip replacements are performed each year in the United States. While most hip replacements provide excellent, long-lasting results, complications can occur in a small percentage of patients. One potential complication is loosening of the hip implant components. If you’ve had a total hip replacement, it’s important to monitor for signs of loosening and follow up with your surgeon if you have any concerns.
What causes a hip replacement to loosen?
There are a few main reasons why a hip replacement implant can loosen over time:
- Normal wear and tear. All joint replacements experience some wear, even under normal conditions. Over many years, the components can slowly loosen from repetitive stress and use.
- Particle debris. Tiny particles can wear off the joint replacement components and cause inflammation. This inflammatory response can cause bone loss around the implant and loosening.
- Trauma or injury. Major impacts, falls, or fractures around the hip implant can disrupt its fit and cause sudden loosening.
- Loosening at the time of surgery. If the hip components are not adequately secured during the initial replacement surgery, early loosening is possible.
Loosening most often occurs gradually over many years. In rare cases, it can occur suddenly after injury or trauma.
How do you know if your hip feels loose?
The most common symptom of a loose hip replacement is pain around the hip joint itself. You may feel deep aching or throbbing pain even during rest. The pain may worsen with activity and weight-bearing.
Other symptoms that can indicate a loose hip replacement include:
- Instability when standing or walking
- Limping or altered gait
- Decreased hip range of motion
- Difficulty bearing weight on the leg with the replaced hip
- Sensation of the hip “giving way”
- Feeling or hearing clicking, clunking, or popping with hip movement
The pain and symptoms of a loose hip replacement are often different from your original hip arthritis pain. Any new onset or worsening pain around your hip implant should be evaluated.
Physical exam signs
During a physical exam, your doctor can check for certain signs that may indicate a loose hip replacement. Some findings may include:
- Tenderness directly over the hip implant
- Warmth, redness, or swelling around the hip joint
- Leg length discrepancy (one leg longer than the other)
- Decreased strength when flexing or extending the hip
- Reduced hip range of motion compared to the unreplaced hip
- Gait abnormalities like limping or waddling
- Audible popping or crunching with hip movements
Imaging tests
If a loose hip replacement is suspected, your surgeon will likely order imaging tests to evaluate the components. Some common tests include:
- X-rays: Can detect signs of implant loosening like subsidence (sinking of the device into bone), change in position of components, or new bone loss around the prosthesis.
- CT scan: Provides detailed views that can show subtle loosening or damage to implants.
- Nuclear bone scan: Looks for abnormal increased blood flow around the hip replacement which can indicate loosening.
- Ultrasound: May detect fluid collection or swelling around a loose implant.
- MRI: Can show soft tissue damage around the prosthesis and inflammation associated with particle debris.
How is a loose hip replacement treated?
If your hip replacement is found to be loose, treatment will depend on the extent of loosening, your symptoms, and your age/activity level. Options may include:
- Monitoring: If loosening is mild with minimal symptoms, your doctor may recommend close monitoring with periodic x-rays.
- Medications: Anti-inflammatory medications or injections can sometimes help manage pain.
- Revision surgery: If loosening is significant, a revision surgery may be required to remove and replace the loose components.
- Spacer insertion: For severe loosening, an antibiotic-loaded cement spacer may be placed temporarily before a formal revision.
- Hip fusion: If you are older or very low demand, a hip fusion procedure may be an option.
Revision hip surgery is a more involved procedure than the initial replacement. Your surgeon will discuss the options given your individual case.
Can a loose hip replacement be prevented?
While some loosening over time is inevitable, there are steps you can take to potentially prevent premature loosening:
- Follow your surgeon’s post-op activity restrictions and hip precautions.
- Attend physical therapy to build strength and properly learn movement patterns.
- Avoid high-impact activities like running to reduce wear.
- Maintain a healthy weight to prevent extra stress on the hip joint.
- Have routine follow-up exams and imaging to monitor for early component loosening.
Avoiding falls and promptly treating any infections can also help prevent loosening. Even with proper precautions, loosening may still occur in a small percentage of patients.
When to see your doctor
You should make an appointment with your orthopedic surgeon if you experience:
- New onset or worsening hip pain
- Instability, limping, or reduced hip mobility
- Clunking, popping, or crunching sensations
- Inability to bear weight through the replaced hip
While many hip replacements continue working well for 20-30 years, loosening can occur in some cases. Being aware of symptoms and promptly reporting them to your surgeon allows early detection to prevent significant damage and determine if any revision procedures are needed.
Conclusion
Loosening of the components is one potential complication after total hip replacement surgery. Gradual loosening over time is normal, but sudden or severe loosening requires prompt evaluation. Symptoms like pain, instability, limping, and clicking should be reported to your surgeon. X-rays, CT scans, and other imaging can diagnose loosening, and options like monitoring, medication, spacer insertion, or revision surgery may be considered depending on the circumstances.
While not entirely preventable, steps like limiting high-impact activities, maintaining a healthy weight, and avoiding falls can help reduce the risk. Loosening that causes pain or disability can nearly always be addressed with the appropriate treatments to keep your hip replacement functioning well.