Introduction: The ButtonFix(®) system represents a new angular stable percutaneous fixation device for stabilisation of fractures of the proximal humerus. The purpose of this study was to present a preliminary report of the radiological and clinical outcome after minimally invasive stabilisation of selected proximal humerus fractures with the ButtonFix(®).
Patients and methods: Seventeen patients with fractures of the proximal humerus were treated in our department with the ButtonFix(®) system. The mean final follow-up was performed 19 months postoperatively. Follow-up included assessment of postoperative reposition, range of motion, the DASH score, the Constant-Murley score, and the Short Form 36 (SF36).
Results: Twelve patients showed anatomical head-to-shaft angles, four revealed minor valgus replacement, and one minor varus replacement. In one patient unplanned revision surgery was necessary due to early secondary fracture dislocation requiring ORIF with an angular stable form plate. Implant removal was performed after 6 weeks in all patients. At the final follow-up, mean range of motion was: flexion 135°, extension 45°, abduction 142°, internal rotation 51°, and external rotation 62°. The mean Constant-Murley score was 70. The mean DASH score was 26 points and the average SF36 score was 76 points. One patient showed radiological signs of avascular necrosis.
Conclusion: The ButtonFix(®) system represents a valuable tool in the treatment of proximal humeral fractures with results indicating fewer complications compared to prior percutaneous fixation devices. Moreover, the ButtonFix(®) seems to be able to maintain reduction even in elderly patients with potentially reduced bone mass.