A new morphological classification for greater tuberosity fractures of the proximal humerus

Abstract

In this study, we describe a morphological classification for greater tuberosity fractures of the proximal humerus. We divided these fractures into three types: avulsion, split and depression. We retrospectively reviewed all shoulder radiographs showing isolated greater tuberosity fractures in a Level I trauma centre between July 2007 and July 2012. We identified 199 cases where records and radiographs were reviewed and included 79 men and 120 women with a mean age of 58 years (23 to 96). The morphological classification was applied to the first 139 cases by three reviewers on two occasions using the Kappa statistic and compared with the AO and Neer classifications. The inter- and intra-observer reliability of the morphological classification was 0.73 to 0.77 and 0.69 to 0.86, respectively. This was superior to the Neer (0.31 to 0.35/0.54 to 0.63) and AO (0.30 to 0.32/0.59 to 0.65) classifications. The distribution of avulsion, split and depression type fractures was 39%, 41%, and 20%, respectively. This classification of greater tuberosity fractures is more reliable than the Neer or AO classifications. These distinct fracture morphologies are likely to have implications in terms of pathophysiology and surgical technique.

Surgical Treatment of Displaced Greater Tuberosity Fractures of the Humerus

“…[22][23][24][25][26] This poor reliability persists even when GT fractures are evaluated in isolation (Neer interobserver/intraobserver 0.31 to 0.35/0.54 to 0.63 and AO interobserver/intraobserver 0.30 to 0.35/0.59 to 0.65). 26,27 The poor reliability of the AO and Neer classifications is likely the result of difficulty in measuring GT displacement using radiography. 18,19,28 However, many studies have shown persistently poor reliability despite the use of radiographic aids, such as stereovisualization and three-dimensional CT. 22,23,26 The Neer and AO classification systems are based solely on fragment displacement 20,21 and do not take into account GT fragment size, morphology, or orientation.…”

“…In 2014, Mutch et al 27 proposed a morphologic classification using a series of 199 isolated GT fractures. The interobersever/intraobserver reliability was 0.73 to 0.77 and 0.69 to 0.86, respectively.…”

“…The interobersever/intraobserver reliability was 0.73 to 0.77 and 0.69 to 0.86, respectively. 27 Three fracture types were described: avulsion, split, and depression. Forty percent of GT fractures were avulsion fractures that involved a small fragment with a fracture line perpendicular to the humeral shaft.…”

Locking plate fixation provides superior fixation of humerus split type greater tuberosity fractures than tension bands and double row suture bridges

“…This study focuses on the split fracture type, which typically involves a large fragment with a fracture line from supero-medial to inferolateral angled 50°with respect to the humeral shaft. This type represents 41% of GT fractures (Mutch et al, 2014).…”

“…The split type, which also makes up 41% of all cases, consists of a fracture line oriented approximately 50°to the humeral shaft. The depression fracture is the least common (18%) and represents an impaction of the GT(Mutch et al, 2014).…”