Objective: To evaluate reconstruction surgery without bone grafting in humeral surgical neck nonunions using either a blade plate or the "Humerusblock'' implant in small head fragments. Design: Retrospective cohort study, Evidence-Based Medicine Level IV. Setting: Paracelsus Medical University Salzburg, Department of Traumatology and Sports Injuries. Patients: Fifty-five patients (mean age, 66.2 years) with symptomatic nonunion after humeral surgical neck fractures were subjected to surgical reconstruction. Intervention: In 45 patients, open reduction and internal fixation using a blade plate was performed (Group 1). In 10 patients, the Humerusblock device was used (Group 2), because the head fragment of each of these patients was too small for plating. In no patients was bone grafting used. Main Outcome Measurements: Shoulder function, level of pain, and bone healing. Results: After a mean follow-up time of 74 months, the overall mean Constant score improved from 30.4% preoperatively to 83.2% postoperatively. The improvement was from 30.5% to 85.3% in Group 1 and from 32.2% to 75.4% in Group 2, which represented statistically significant improvements for both groups (P < 0.01). Radiologic bone healing was achieved in 51 patients (93%). The overall complication rate was high, 15%, and complications included plate loosening, avascular head necrosis, persistent nonunion, and infection. Conclusions: Nonunion of humeral surgical neck fractures can be successfully treated by surgical reconstruction without bone grafting using either a blade plate or the Humerusblock for small head fragments. However, an increased complication rate is associated with this challenging posttraumatic pathology.