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 pelvis and acetabulum safe corridors and directions for pins insertion.
Methods
A cadaveric study using two bony and three cadaveric pelves. Half pins were inserted in specific demarcated sites and tested for resistance to pullout, and safety of nearby neurovascular structures.
Results
Iliac crest, AIIS, ASIS, PIIS, PSIS, supra acetabular region, ischial tuberosity both triangular and quadrangular areas, anterior column of the acetabulum lateral to the ASIS, and the lateral one cm of ala of the sacrum are safe pin insertion sites. While the area 1cm medial to the AIIs and AIIS, and the rest of the ala of the sacrum is unsafe.
Conclusion
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.