Safe Supra‐Acetabular Pin Insertion in Relation to Intraosseous Depth

Abstract

In pelvic fractures, dysfunction of the pelvic ring is often stabilized with supra-acetabular pin insertion. In existing literature, there are heterogeneous indications on proper pins selection and inclinations. Therefore, this study aimed to quantify the narrowing of safe pin corridors in the transverse and sagittal planes with increments of intraosseous screw depths. A computer algorithm created cross-sections over three-dimensional pelvic reconstructions at sagittal inclinations from 45°cranial to 45°caudal in 5°i ncrements. Templates of screw depths spanning 60-120 mm in 15 mm increments were disposed in the transverse plane from 45°medial to 45°lateral. Each intraosseous screw depth and transverse angle were evaluated for intraosseous containment to evaluate ranges narrowing with increasing screw depths. The 60-mm depth resulted in the largest sagittal range (60.9°± 6.9°) and transverse range (27.5°± 4.1°) at 30°caudal. Increasing depths by 15 mm resulted in ranges being significantly different from one another (p < 0.01). The sagittal plane of 20°cranial had the highest frequency of insertion for all depths, while transverse ranges were narrowed (p < 0.01). Bisecting angles were similar for sagittal planes 20°cranial to 30°caudal with an average of 27.9°± 1.2°(p ≥ 0.115). In conclusion, while 60 mm depths can be inserted with the highest discretion, 15 mm increments in depth significantly reduce safe ranges. Screws depths above 90 mm have low frequencies of insertion, should be inserted more cranially and must be considered prone to breaching.

Biomechanical comparative study on external fixators of new configurations in the treatment of Tile C pelvic injury

“…While the focus of this study is on the mechanical properties of the external fixator, imaging-related factors require equal attention to maximise stability while www.nature.com/scientificreports/ maintaining a clinically acceptable level of MRI quality 21,22 . Additional limitation of the study is given by the fact that single lengths for the screws were used while studies performed by Morandi et al 23 and Young et al 24 have proven that for these insertion points multiple trajectories and pin lengths are safe to be used.…”

Study of anatomical parameters and intraoperative fluoroscopic techniques for transiliac crest anterograde lag screws fixation of the posterior column of the acetabulum

“…Present results are comparable with those by other authors. The Morandi [ 12 ] explored the narrowing ranges of safe insertion with increasing screw lengths in the supraacetabular area and the relationship between anatomical size of the pelvis and screw size. The author concluded that the 60 mm screw depth provided the best option to limit breaching of the pelvic wall having the largest range in both transverse and sagittal directions.…”

“…Young et al [ 20 ] sectioned the pelvis by reconstructing three-dimensional model of the pelvis to determine the greatest degree of sagittal pin spanning angulation between two iliac crest pins and how intraosseous depth affects these angulations. Morandi et al [ 12 ] also designed the study that A computer algorithm created cross‐sections over three‐dimensional pelvic reconstructions to quantify the narrowing of safe supra‐acetabular pin corridors in the transverse and sagittal planes with increments of intraosseous screw depths. All the measures we performed were based on different entry points.…”

Successful coil embolization of a ruptured pseudoaneurysm of the superior gluteal artery after a percutaneous awake robot-assisted sacroiliac joint fusion: illustrative case

“…10,13 The use of shading scanners, fluoroscopybased imaging, three-dimensional C-arm, preoperative CT-based planning, computer navigation, and robot-assisted techniques have also shown promising results in ensuring accurate and safe screw placement while minimizing the risk of SGA injury. [15][16][17][18]…”