Purpose: This experimental study is to know what the safe zones are
and angles of half pin insertion in lumber vertebrae, and if there are
another new sites for half pin insertion.
Methodology: A cadaver study using two bony and four cadaveric
specimens was undertaken to examine the safe sites for half pins
insertion in lumber vertebrae. Half pins were inserted in specific
demarcated sites.
Results: From our study we suggest that the pedicle of the lumber
vertebrae is the safe and strong region for insertion of the half pins
with 10 to 40 degrees divergent from the mid line, where the new site
of half pin insertion in the vertebral body anterior and at the level of
transverse process is safe at angle lies between 50 to 60 degrees from
the sagittal plane in L4 and L5.
Conclusion: We concluded that the application of external fixators in
the lumber spine is valuable with good safety margins of half pin
introduction in both pedicle and vertebral body.