Background and Objectives: Posterior fracture dislocations are rare. There is currently no uniformity regarding treatment. Therefore, outcomes are difficult to compare. We evaluated clinical and radiological outcomes of patients with humeral head posterior fracture dislocation treated with an open posterior reduction and then fixed with a biomechanically validated configuration of blocked threaded wires. Materials and Methods: 11 consecutive patients with humeral head three-part posterior fracture dislocation were treated by reduction through a posterior approach and fixed with blocked threaded wires. All patients were clinically and radiographically evaluated after a mean follow-up of 50 months. Results: The mean irCS was 86.1% (range: 70.5-95.3%). No significant difference was found between irCS at 6 and 12 months postoperatively and the final follow-up. Six patients noted their pain intensity as 0/10, three as 1/10, and two as 2/10. The postoperative reduction was considered as excellent in eight patients (Bahr's criteria) and good in the remaining three; at the final follow-up, reduction was excellent and good in seven and four patients, respectively. The mean neck-shaft angles at FU 0 and at the final FU were 137° and 132°, respectively. No signs of avascular necrosis, non-union, and arthritis progression were seen. No recurrence of dislocation or posterior instability symptoms were reported. Conclusions: We believe that our very satisfactory results stem from: (1) the manual reduction of the dislocation through a vertical posterior surgical approach, which does not produce further osteocartilaginous damage of the humeral head; (2) no multiple perforations of the humeral head are performed; (3) the threaded wires have a smaller diameter than the screws, therefore they preserve the bone tissue of the humeral head; (4) deperiostization or further detachment of soft tissues are not expected; (5) the adopted and validated system is stable and limits translation, torsion, and the collapse of the humeral head.
Keywords: complex proximal humerus fracture dislocation; composite tuberosity shield fragment; percutaneous blocked threaded wires; posterior approach for posterior shoulder fracture-dislocation; posterior shoulder fracture dislocation.