The scapular glenopolar angle: standard values and side differences

Abstract

GPA values depend on the method of measurement used. Measurements made on 3D CT reconstructions and Neer I views showed almost the same values as those measured on bone specimens. The values measured on AP shoulder views and AP chest radiographs were statistically significantly lower. Side-to-side variability (right and left) measured on 3D CT reconstructions was insignificant, and the obtained values corresponded to the values from bone specimens. Therefore, the best method to measure the GPA is a 3D CT reconstruction and an exact Neer I projection.

Scapular glenopolar angle in anterior shoulder dislocation cases

“…[11,12] There is no consensus for the optimal radiological technique to measure GPA or the standard values of GPA in the literature. [13] GPA can be measured directly on cadaver specimens, 3D scapula reconstructions, Neer view X-ray images, AP shoulder or AP chest radiographs. [13] In this study, GPA measurement was performed on true (Grashey) AP shoulder radiographs.…”

“…[13] GPA can be measured directly on cadaver specimens, 3D scapula reconstructions, Neer view X-ray images, AP shoulder or AP chest radiographs. [13] In this study, GPA measurement was performed on true (Grashey) AP shoulder radiographs. In the literature, there are studies with measurements made on different imaging views.…”

“…GPA is the angle formed by the intersection of the line joining the most caudal and most cranial points of the glenoid cavity and the line joining the most cranial point of the glenoid cavity to the most caudal point of the scapula body. [4,5] GPA is normally used to measure rotational sequence disorders of the glenoid in scapula fractures on anteroposterior radiographs. [6] In this study, GPA was investigated on direct radiographs of anterior shoulder dislocation cases for the first time with an aim to assess the glenoid with GPA measurements in cases with anterior shoulder dislocation.…”

Quadruple Disruption of the Superior Shoulder Suspensory Complex (SSSC) and Outcome after One Year of Conservative Treatment: A Case Report

“…Hence, the recommendation of surgical fixation for such unstable fracture patterns is established, especially if fracture dislocation is present. Good clinical results after conservative therapy of double disruptions/floating shoulders with only minimally displaced fractures exist [35][36][37][38][39][40], yet more studies report the inferior outcome of conservatively versus surgically treated displaced fractures [41][42][43][44]. There is a lack of data concerning outcome after conservative treatment for triple or quadruple SSSC disruptions.…”

How to deal with a glenoid fracture

“…31 The GPA is in the range of 36° and 43° 32 and the most common recommendation for operative treatment is a GPA < 20° (Fig. 3), 30 although some controversy still exists on this point.…”