From the Guidelines
Joint hardware becomes infected when bacteria enter the surgical site and colonize the implant surface, typically through contamination during surgery, hematogenous seeding, or contiguous spread from a local source, as noted in a study published in 2013 1. This can occur during the initial surgery through contamination from the patient's skin, airborne particles in the operating room, or from surgical instruments. Infections can also develop later when bacteria from another infection in the body travel through the bloodstream and settle on the implant. Some key points to consider include:
- Common risk factors for joint hardware infection include compromised immune systems, diabetes, obesity, rheumatoid arthritis, and previous joint infections.
- The bacteria most frequently responsible are Staphylococcus aureus and Staphylococcus epidermidis, which form biofilms on the implant surface that protect them from antibiotics and the immune system, as discussed in a study from 2020 1.
- Prevention strategies include preoperative antibiotics, careful skin preparation, proper surgical technique, and maintaining strict sterility in the operating room.
- Patients with joint hardware should also receive antibiotic prophylaxis before dental procedures or other invasive treatments that might introduce bacteria into the bloodstream, as recommended in guidelines from 2013 1 and 2013 1. It's also worth noting that the management of prosthetic joint infections requires a multi-disciplinary approach and strong collaboration between medical and surgical specialists, as emphasized in a study from 2020 1. Additionally, diagnosis and prevention of periprosthetic joint infections can be aided by multiple aerobic and anaerobic bacterial periprosthetic tissue cultures, implant sonication fluid aerobic and anaerobic bacterial cultures, and implant sonication fluid nucleic acid amplification testing, as noted in a study from 2020 1.
From the Research
Joint Hardware Infection Routes
Joint hardware can become infected through three different routes:
- Direct implantation: This occurs when the joint prosthesis is contaminated during the implantation process 2.
- Hematogenic infection: This type of infection occurs when bacteria enter the bloodstream and travel to the joint prosthesis, causing an infection 2.
- Reactivation of latent infection: This type of infection occurs when a latent infection, such as osteomyelitis, is reactivated after joint prosthesis implantation 2.
Risk Factors for Joint Hardware Infection
Several risk factors can increase the likelihood of joint hardware infection, including:
- Advanced age 2
- Malnutrition 2
- Obesity 2
- Diabetes mellitus 2
- HIV infection at an advanced stage 2
- Presence of distant infectious foci 2
- Antecedents of arthroscopy or infection in previous arthroplasty 2
- Use of vancomycin as surgical antibiotic prophylaxis instead of cefazolin 3
Prevention of Joint Hardware Infection
To prevent joint hardware infection, surgical antibiotic prophylaxis is crucial. Cefazolin is a commonly used antibiotic for this purpose, and studies have shown that it is effective in preventing surgical site infections 4, 5. However, the use of vancomycin as surgical antibiotic prophylaxis may increase the risk of infection compared to cefazolin 3. In some cases, the use of vancomycin and cefazolin together may be beneficial in reducing the risk of surgical site infections 6.
Diagnosis and Treatment of Joint Hardware Infection
Diagnosing joint hardware infection can be challenging, but it typically involves a combination of clinical evaluation, imaging studies, and laboratory tests 2. Treatment of joint hardware infection usually requires extensive surgical debridement and adequate antibiotic therapy 2. In some cases, a two-stage treatment approach may be necessary, involving the removal of the infected prosthesis and the use of a spacer until the infection is resolved 2.