Purpose Traumatic posterior instability of the sternoclavicular joint is a potentially life-threatening injury. In contrast to the low incidence there is a plethora of diferent strategies to treat this lesion. It was the objective of this retrospective analysis to evaluate and further develop current strategies. Methods In this retrospective analysis all posterior dislocations that were diagnosed and treated between 2011 and 2018 were included. In this 7 year period, eight male patients (median age 32 years) were operated. Results Three patients were not diagnosed at the primary institution and were referred later. Five patients were treated with an anterior buttress plate with clavicular stabilisation only. One patient was stabilized with a temporary sternoclavicular arthrodesis. Two patients were operated using an autologous tendon graft. All of the patients underwent an immediate postoperative CT-scan that documented the anatomical articulation. All patients treated with a plate underwent implant removal. A inal CT examination after removal documented the maintenance of the anatomic alignment. Conclusions The buttress plate technique with clavicular screw ixation is a suicient treatment to restore and preserve a normal sternoclavicular alignment. The technique inds its indication in unidirectional posterior instability. Level of evidence IV.