Septic arthritis of the first metatarsophalangeal joint: a case report.

Introduction: we describe the case of a 24-year-old male with an initial diagnosis of arthritis of the first metatarsophalangeal joint (MTP). In the magnetic resonance imaging (MRI) the abnormal findings were a bipartite medial sesamoid versus fracture of the medial sesamoid. During follow-up, the patient developed a fistula in the first MTP with a positive culture for methicillin-sensitive Staphylococcus aureus (MSSA), leading to the diagnosis of septic arthritis (SA) of the first MTP. Treatment involved surgical debridement and targeted antibiotic therapy, resulting in good outcomes and satisfactory progress.

Conclusion: sesamoid bone pathology is rare, with fractures and sesamoiditis being the most common conditions. Acute or chronic infection osteomyelitis of sesamoids is extremely unusual, and aggressive treatment is required. Sample collection should be performed to initiate targeted antibiotic therapy for the causative pathogens, with Staphylococcus aureus and Pseudomonas aeruginosa being the most frequent. Subsequently, extensive surgical debridement should be performed, aiming to avoid complete sesamoidectomy due to its significant comorbidity.