What Is the Diagnostic "Algorithm" for Infected Total Ankle Arthroplasty (TAA)?

Area of Science:

• Orthopedic Surgery
• Infectious Disease
• Diagnostic Medicine

Background:

• Periprosthetic joint infections pose significant challenges in orthopedic surgery.
• Accurate diagnosis of total ankle arthroplasty (TAA) infection is crucial for effective treatment and patient outcomes.

Purpose of the Study:

• To outline diagnostic criteria for periprosthetic ankle infection.
• To provide a stepwise approach for identifying TAA infections.

Main Methods:

• Clinical evaluation of symptoms and signs (pain, erythema, warmth, sinus tract, abscess).
• Assessment of inflammatory markers: erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP).
• Synovial fluid aspiration for cell count, differential, and microbial cultures (repeated if necessary).
• Consideration of nuclear imaging and histologic examination for diagnosis.

Main Results:

• Sinus tracts communicating with the joint strongly suggest TAA infection.
• Elevated inflammatory markers warrant joint aspiration when no sinus tract is present.
• Identification of the same organism in at least two synovial fluid cultures confirms infection.
• Histologic examination (>5 neutrophils/high-power field) aids in diagnosis during surgery.

Conclusions:

• Clinical presentation combined with laboratory and imaging findings facilitates TAA infection diagnosis.
• A systematic approach involving clinical signs, inflammatory markers, and synovial fluid analysis is recommended.
• Early and accurate diagnosis is essential for appropriate management of periprosthetic ankle infections.