Temporomandibular joint ankylosis associated with psoriasis and familial Mediterranean fever: a rare case report.

Autoimmune and autoinflammatory diseases, though traditionally considered distinct, share overlapping pathogenic mechanisms that complicate diagnosis and management, particularly in joint involvement. Psoriasis-especially when associated with inflammatory joint manifestations-and familial Mediterranean fever (FMF) exemplify this overlap. Temporomandibular joint (TMJ) involvement is well recognized in connective tissue diseases; however, its presentation in such overlapping clinical states remains underreported and poorly understood. To the best of our knowledge, we present the first documented case of TMJ fibrous ankylosis in a patient with coexisting psoriasis and FMF. A 40-year-old female developed right TMJ fibrous ankylosis, confirmed by clinical examination and imaging. Despite multiple arthrocentesis procedures and conservative treatments, she experienced progressive limitation in mouth opening, ultimately requiring open joint surgery and arthroplasty. This rare case underscores the importance of considering TMJ involvement in patients with systemic inflammatory diseases and highlights the diagnostic and therapeutic challenges encountered when autoimmune and autoinflammatory conditions overlap.