Internal fixation of proximal humerus fractures using the Polarus intramedullary nail

It has been stated that proximal humeral fractures are the last unsolved fractures in orthopedics. In this study, we evaluate the results of the Polarus nail, in order to constitute to the controversial problem of the treatment of proximal humerus fractures.

Between 2003 and 2005, 27 patients with severely displaced proximal humeral fractures were treated with the Polarus intramedullary system. The fractures were classified according to the Neer classification system. There were 16 2-part fractures and 11 3-part fractures. At the 12-months follow up we graded the clinical outcome of the patients according to the Neer scoring system.

The duration from time of injury to operation ranged from 1 to 6 days. The mean operative time was 55 min and no need of blood transfusion was recorded. Bony union was obtained in 27 patients. There were no cases of nonunion and the period from operation to the appearance of sufficient bridging callus on radiographs was 5-11 weeks (mean 6 weeks). In one patient, a backed-out proximal screw was recorded. Stiffness of the shoulder was seen in one patient and avascular necrosis of the head of humerus in another. Related to the clinical outcome, six patients had an excellent result, 15 patients had a satisfactory result, four patients had an unsatisfactory result, and two patients had a poor result. The 77.78% of the patients had an excellent or satisfactory clinical outcome. There was significant difference in the functional outcome between patients younger than 65 years (91.55) and those older than 65 years (80.22) (P < 0.05). No significant difference was recorded in the Neer score between the patients with a 2-part fracture and the patients with a 3-part fracture (80.18) (P > 0.05).

The Polarus nail is designed to provide stable fixation with a straightforward insertion and targeting procedure. The fact that 77.78% of the patients had an excellent or satisfactory clinical outcome, suggest that Polarus humeral rod system can be a worthy alternative to traditional operative methods for displaced proximal fractures of the humerus.