Polarus nail fixation for proximal humeral fractures

PURPOSE. To report the outcomes of Polarus nail fixation for displaced proximal humeral fractures. METHODS. Medical records of 19 men and 27 women aged 26 to 84 (mean, 63) years who underwent fixation using a standard Polarus nail (n=34) or Polarus plus nail with shaft extension (n=12) for proximal humeral fractures of 2 and 3 parts (n=34) and 2-part with extension to the shaft (n=12) were reviewed. Fracture union, neck shaft angle, and hardware complications were evaluated using radiographs. Outcomes were assessed using the Constant score, the visual analogue scale for pain, and subjective satisfaction. The range of motion, grip strength, and ability to return to work were also recorded. RESULTS. The mean follow-up was 20 (range, 15-28) months. The mean humeral neck shaft angle was 137.2º. 44 (96%) patients achieved fracture union after a mean of 14 (range, 11-16) weeks. Two patients with 3-part fractures did not unite; one of them underwent hemiarthroplasty and the other consented for nail removal only. Complications included temporary radial nerve palsy (n=2), impingement symptoms caused by the prominent metal work (n=10), and missing of the proximal screws in the nail (n=4). Respectively in patients aged <60 (n=15) and ≥ 60 years (n=31), the mean Constant scores were 79 and 67 (p=0.04). The mean pain score improved from 93 to 15.5 at 12 months. 16 patients were very satisfied, 22 were satisfied, and 8 were not satisfied with the outcome. Of the latter, 3 were aged <60 years and 5 were aged ≥ 60 years. CONCLUSION. Polarus nail fixation for displaced proximal humeral fractures achieved good fracture union and satisfactory functional outcome, particularly in younger patients and those in active employment, but elderly dependent patients tended to have poor functional results. The rates of minor hardware problems and non-union in 3-part fractures were relatively high.