Periprosthetic Joint Infection (PJI) Surgery: Types, Procedures, Recovery, and Risks

What is PJI surgery?

PJI surgery refers to a range of complex surgical procedures designed to treat Periprosthetic Joint Infection (PJI), a severe complication involving infection around a prosthetic joint implant, such as those used in hip or knee replacements.

Understanding PJI: What is it?

Periprosthetic Joint Infection (PJI) is a serious and challenging complication following total joint arthroplasty (TJA), where bacteria or other microorganisms colonize the artificial joint and surrounding tissues. Unlike typical infections, PJI involves the formation of a biofilm on the implant surface, a protective layer that makes bacteria highly resistant to antibiotics and the body's immune response. This biofilm makes complete eradication of the infection without surgical intervention extremely difficult, often necessitating specialized surgical approaches to remove the infected tissue and, frequently, the implant itself.

Why is PJI Surgery Necessary?

PJI is a devastating complication that can lead to significant pain, swelling, reduced joint function, and systemic illness. If left untreated, the infection can spread, cause bone destruction (osteolysis), implant loosening, chronic pain, and in severe cases, lead to limb amputation or even be life-threatening. The unique challenge of PJI lies in the biofilm formation, which renders systemic antibiotics largely ineffective on their own. Therefore, surgical intervention becomes paramount to physically remove the infected material and address the source of the infection.

Types of PJI Surgical Procedures

The specific surgical approach for PJI depends on several factors, including the patient's overall health, the virulence of the infecting organism, the duration of the infection, and the stability of the prosthetic implant. The primary goals are to eradicate the infection, preserve or restore joint function, and alleviate symptoms.

• Debridement and Implant Retention (DAIR):

  • Description: This procedure involves thoroughly cleaning the infected joint (debridement), removing infected soft tissues, and exchanging the modular components of the prosthesis (e.g., polyethylene liner in a knee replacement or femoral head in a hip replacement). The main prosthetic components (femoral and tibial components, or acetabular and femoral stem) are retained.
  • Indications: Typically performed for acute infections (within weeks of initial surgery or acute hematogenous spread to an existing implant) where the implant is stable and the infecting organism is less virulent.
  • Success Factors: Early diagnosis and intervention, susceptible organisms, and good patient health are crucial for success.

• One-Stage Exchange Arthroplasty:

  • Description: All components of the infected prosthesis are removed, the joint is thoroughly debrided and irrigated, and a new, sterile prosthesis is implanted during the same surgical session.
  • Indications: Often considered for less virulent organisms, well-defined infections, and patients who can tolerate a longer, more complex single surgery. It requires meticulous surgical technique and often involves the use of antibiotic-impregnated bone cement.
  • Advantages: Eliminates the need for multiple surgeries, potentially reducing overall recovery time and cost.

• Two-Stage Exchange Arthroplasty:

  • Description: This is considered the gold standard for chronic or difficult-to-treat PJI.
    • Stage 1: The infected prosthesis is completely removed, extensive debridement of all infected tissue occurs, and an antibiotic-impregnated spacer (often made of cement) is temporarily implanted. The patient then undergoes a prolonged course of intravenous antibiotics (typically 4-6 weeks).
    • Stage 2: After a period where infection markers normalize and the patient is clinically stable, the antibiotic spacer is removed, and a new, sterile prosthesis is implanted.
  • Indications: Preferred for chronic infections, virulent organisms, significant bone loss, or when DAIR has failed.
  • Advantages: Allows for a prolonged period of local antibiotic delivery and systemic antibiotic treatment to eradicate the infection before a new implant is placed, leading to higher success rates.

• Resection Arthroplasty (Girdlestone procedure for hip):

  • Description: The infected prosthesis is removed, and no new implant is inserted. The joint space is left empty or filled with cement and scar tissue. This leaves a flail joint or pseudoarthrosis.
  • Indications: Reserved for patients with severe, uncontrollable infections, poor bone stock, multiple failed surgeries, or those who cannot tolerate further reconstructive surgery.
  • Outcome: While it eradicates the infection, it results in significant limb shortening, instability, and functional impairment, often requiring assistive devices for ambulation.

• Arthrodesis (Joint Fusion):

  • Description: The joint is surgically fused, eliminating motion but providing a stable, pain-free limb.
  • Indications: Considered in cases of failed PJI treatment where joint motion is no longer a priority, and stability is needed.
  • Outcome: Successful in eradicating infection and providing stability, but at the cost of permanent loss of joint mobility.

• Amputation:

  • Description: Surgical removal of the limb.
  • Indications: A last resort for limb-threatening, intractable infections that have failed all other treatments and are causing severe systemic illness or are life-threatening.

The Surgical Process

Regardless of the specific type, PJI surgery is a major undertaking. It typically involves:

• Pre-operative Assessment: Extensive evaluation, including blood tests (e.g., C-reactive protein, erythrocyte sedimentation rate), joint aspiration for culture, and imaging studies to confirm the diagnosis and plan the approach.
• Anesthesia: General anesthesia is typically used.
• Incision and Exposure: The existing surgical incision is often reopened.
• Debridement and Implant Removal: All infected soft tissues are meticulously removed, and the existing prosthesis (or components thereof) is extracted.
• Irrigation: The joint is thoroughly irrigated with large volumes of saline and sometimes antiseptic solutions.
• New Implant Insertion (if applicable): In one-stage exchanges or the second stage of a two-stage procedure, a new, sterile prosthesis is implanted.
• Closure: The wound is closed in layers.
• Post-operative Care: Patients are typically admitted for several days to weeks, receiving intravenous antibiotics and pain management.

Recovery and Rehabilitation

Recovery from PJI surgery is often prolonged and challenging.

• Antibiotic Therapy: A crucial component of treatment, often lasting several weeks to months, tailored to the specific bacteria identified. This may involve intravenous antibiotics initially, transitioning to oral antibiotics.
• Pain Management: Extensive pain control is required.
• Physical Therapy: Rehabilitation is vital, though often delayed or modified compared to standard joint replacement. The focus is on restoring strength, range of motion, and functional mobility, while protecting the healing tissues and ensuring infection eradication.
• Weight-Bearing Restrictions: Depending on the procedure and stability of the new implant or spacer, weight-bearing restrictions may be in place for an extended period.
• Monitoring: Regular blood tests and clinical follow-ups are necessary to monitor for infection recurrence.

Potential Risks and Complications

Beyond the general risks of any major surgery (bleeding, blood clots, nerve damage, adverse reaction to anesthesia), PJI surgery carries specific risks:

• Recurrent Infection: Despite aggressive treatment, PJI can recur, necessitating further surgery.
• Antibiotic Resistance: Development of antibiotic-resistant bacteria.
• Bone Loss: Further bone loss can occur, complicating future reconstructions.
• Joint Stiffness or Instability: Especially after resection arthroplasty or if extensive soft tissue removal is required.
• Limb Length Discrepancy: Can occur after implant removal or complex reconstructions.
• Fracture: Periprosthetic fractures can occur during implant removal or insertion.
• Renal/Hepatic Toxicity: Due to prolonged, high-dose antibiotic therapy.

Prognosis and Long-Term Outlook

The success rate of PJI surgery varies depending on the type of procedure, the infecting organism, patient comorbidities, and adherence to post-operative protocols. Two-stage exchange arthroplasty generally has the highest success rates, ranging from 85-95% for infection eradication. However, even with successful eradication, some patients may experience ongoing pain, reduced function, or limitations in activity compared to those who have undergone a routine, uninfected joint replacement. Long-term follow-up is essential.

Prevention of PJI

Preventing PJI is paramount. Strategies include:

• Pre-operative Optimization: Addressing patient health issues (e.g., diabetes control, smoking cessation, dental health).
• Intra-operative Measures: Strict sterile technique, prophylactic antibiotics, and specialized operating room environments.
• Post-operative Care: Careful wound management and patient education on signs of infection.

Consulting a Specialist

PJI is a complex condition requiring management by a multidisciplinary team, typically including orthopedic surgeons specializing in joint replacement and infection, infectious disease specialists, and physical therapists. If you have a joint replacement and experience symptoms such as persistent pain, swelling, warmth, redness, fever, or drainage from the surgical site, seek immediate medical attention. Early diagnosis and intervention are critical for improving outcomes in PJI.