Stress fracture of the midshaft clavicle associated with sternocostoclavicular hyperostosis—Case report

INTRODUCTION: Stress fracture is generally a result of cumulative and repetitive stress in athletes, which accelerates the normal remodeling process of bones, and the most frequently involved areas are the tibia and metatarsal bones. Therefore, stress fractures of the midshaft of the clavicle are very rare. PRESENTATION OF CASE: A 58-year-old female was admitted to our hospital because of pain in the middle of the right clavicle. Based on laboratory and radiographic inspection, it was concluded that the stress fracture of the midshaft of the clavicle in this case was caused by sternocostoclavicular hyperostosis (SCCH). Because the clavicular fracture had no displacement or callus formation, conservative treatment with a clavicle band was undertaken. Shoulder function at the final follow-up visit was satisfactory. DISCUSSION: SCCH is a rare chronic inflammatory disorder of the axial skeleton and ossifying diathesis associated with a predominantly osteogenic response. Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome and ankylosing spondylitis (AS) should be considered in the differential diagnosis of SCCH. If a patient with this type of fracture has no history of traumatic injury or sports activity, the differential diagnosis might be very difficult. CONCLUSION: We report the case of a female who had a stress fracture of the midshaft of the clavicle associated with SCCH in SAPHO or AS. Although the patient was treated conservatively, and the shoulder function was satisfactory at the final follow-up visit, re-fracture may occur in the future.