Open reduction and internal fixation of three- and four-part proximal humeral fractures by intrafocal distraction: a clinical and radiographic study of thirty-two cases with five to ten years of follow-up.

PURPOSE: The disadvantage of ORIF of proximal humerus fracture (PHF) by intrafocal distraction is that once the device is inserted, it cannot be removed. This study was designed to evaluate the tolerance of such a titanium alloy device at five years of minimal follow-up (FU) and secondarily to assess the relevance of the osteosynthesis of these fractures. METHOD: Thirty-two patients operated for PHF and implanted with a titanium alloy device between 2009 and 2011 were reviewed: fifteen three-part fracture (3-PF) with mean age 65.2 ± seven years and mean FU at 86 months, and seventeen four-part (4-PF) with mean age 62.9 ± 12 years and mean FU at 88 months. RESULTS: There were no signs of clinical or radiological incompatibility to the metal. The lateral cortex of the humeral shaft at the wedge component level of the device was thinner than pre-operatively in half of the cases. For the fifteen 3-PF, the median raw and weighted constant score (CS) were 75 and 100, respectively. Only one case presented avascular necrosis (AVN). For the seventeen 4-PF, the median raw and weighted CS were 64 and 88, respectively. Seven cases presented AVN and none of them seven had initially a dorsomedial metaphyseal extension of the humeral head. Kaplan-Meier survivorship analysis, with 95% confidence interval, was calculated at 89.7% (79.7-100%) survivorship at 7.18 years of follow-up. CONCLUSIONS: This study shows no incompatibility of the titanium alloy device, radiological signs of localized stress shielding in half of the cases with no functional impact, excellent clinical and radiological evolution of the 3-PF, and AVN in all 4-PF without dorsomedial metaphyseal extension of the humeral head whereas most of cases without AVN had dorsomedial metaphyseal extension.