Background:
The external fixator is used in emergency stabilization of
unstable pelvic fractures; however, its role as a definitive fixation
device remains unestablished. The main problem is the risk of
injury to surrounding neurovascular structures with no definite
safe corridors for pin insertion. The purpose of the current
cadaveric study is to outline safe safe corridors in the pelvis and
acetabulum and directions for pin insertion.
Methods:
A cadaver study using two bony and three cadaveric pelves was
undertaken. Half pins were inserted in specific demarcated sites
and tested for resistance to pullout and safety of nearby
neurovascular structures.
Results:
The iliac crest, anterior inferior iliac spine, anterior superior iliac
spine, posterior inferior iliac spine, and posterior superior iliac
spine, supraacetabular region, ischial tuberosity both triangular
and quadrangular areas, anterior column of the acetabulum
lateral to the anterior superior iliac spine, and the lateral 1 cm of
ala of the sacrum are safe pin insertion sites. While the area 1 cm
medial to both the anterior inferior iliac spine and the anterior
superior iliac spine, and the rest of the ala of the sacrum is
unsafe.
Conclusions:
There are many safe areas for half pin insertion in pelvic and
acetabular fractures, while there are other unsafe areas.
Adequate knowledge of the safe sites and direction of pin
insertion decrease the risks of neurovascular injury and allow a
wider use of external fixators in pelvic and acetabular fractures.