Expandable intramedullary nails for humeral fractures: a systematic review of clinical and radiological outcomes.

The Fixion(™) system (Disc-O-Tech Medical Technologies, Herzeliya, Israel), which is currently the only expandable nailing system available for use in the humerus, has a number of purported advantages over the standard locked humeral nail, including a reduction in operating and fluoroscopy time since locking screws are not required. A systematic review was undertaken of all published (AMED, CINAHL, EMBASE and Medline via the Ovid platform) and unpublished or grey literature research databases from inception until 1st December 2010. Demographic data, clinical and radiological outcomes, and complications were extracted from each study by two independent investigators, and each study underwent independent critical appraisal using the CASP appraisal tool. Thirteen studies were deemed eligible for review, identified from a total of 154 citations. These included a total of 176 patients with 180 fractured humeri treated with expandable nails. Overall, 7.8% of humeral fractures treated with an expandable nail went on to non-union. Intra- and post-operative device failure rate was found to be 1.1 and 2.8%, respectively. These data compare favourably to published data on the outcome of locked humeral nails. However, there were numerous methodological flaws in the current evidence base; there were no comparative studies, treatment groups were heterogeneous, and there was no blinding of assessors or patients. Initial data indicate that the expandable humeral nail may be an acceptable form of treatment for humeral fracture or impending fracture, but high-quality comparative studies are needed to confirm these findings.