The purpose of this study is to evaluate clinical results of internal fixation using Polarus humeral nail for proximal humeral fractures. Thirty shoulders of 30 patients (19 females, 11 males) underwent intramedullary fixation using Polarus humeral nail from September 2004 to January 2009. The mean age was 60 years old (range 18 to 82 years) and the average period of follow up was 13 months (range 6-48 months). According to the AO classification, 5 fractures were classified as A2, 6 as A3, 15 as B1, 1 as B2, 1 as B3 and 2 as C3. We checked radiographic results, JOA score, and the range of shoulder motion. Two patients underwent a second operation because of displacement, and we also used polarus humeral nail for the second surgery. All patients obtained bone union and the mean time for union was 3.7 months. The average of JOA score was 82.1(52-100). The average of shoulder motion was 144 degrees for flexion, 42 degrees for external rotation, L2 for internal rotation. Osteosynthesis of proximal humeral fracture using Polarus humeral nail was a useful procedure. It is important to insert the nail from the top of the humeral head. To prevent cut-out of the greater tuberosity's screws, it is nessesary to combine rotator cuff and screw using suture.
