Thoracic outlet syndrome in a patient with SAPHO syndrome - A case report.

INTRODUCTION AND IMPORTANCE: Thoracic outlet syndrome (TOS) includes disorders caused by compression of the neurovascular structures in the upper thoracic outlet (Roos and Owens, 1996 [1]; Bürger, 2014; Curuk, 2020 [3]). Depending on the compressed structure, it is categorized into neurological, arterial and venous TOS. SAPHO syndrome (synovitis-acne-pustulosis-hyperostosis-osteitis syndrome) is a rare chronic inflammatory disease of unknown etiology. With its typical involvement of sternoclavicular joint and clavicle, complication due to hyperostosis in this region, leading to thrombosis of the subclavian vein have been reported in some cases of SAPHO syndrome. Between 2015 and 2019 488 patients, suffering from neurological, vascular or combined TOS presented at our department. Depending on clinical and diagnostic results surgical therapy was performed in 175 cases via the transaxillary approach, including complete first rib and/or cervical rib resection, neurolysis of plexus brachialis, thoracic sympathectomy and vascular reconstruction if indicated (Curuk, 2020). During this period, only one single patient presented with SAPHO syndrome with thrombosis of the subclavian vein and neurovascular TOS.

CASE PRESENTATION: We present a 50-year-old female patient, in line with the SCARE 2020 criteria (Agha et al., 2020 [12]) suffering from extremely rare combination of neurovascular TOS and SAPHO syndrome with thrombosis of the left subclavian vein due to hyperostosis of the left clavicle.

CONCLUSION: Progressive bone changes associated with SAPHO syndrome can lead to narrowing of the thoracic outlet. Pharmacological therapies to avoid the progression of the hyperostosis of the costoclavicular joint and the clavicle do currently not exist. First rib resection is a therapeutic option to widen the space in the upper thoracic region. Surely, it is a rare condition and more long-term follow-up data are required.