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Koga Improved PETA for LFS at L5/S1

treatment of LDH with migration into the hidden zone. diagnostic methods, the need for surgical treatment
The authors used PETA in 9 cases of hidden-zone of LFS has increased. On the other hand, patient
[6]
LDH, and successful removal of LDH was confirmed demand for minimally invasive surgery is also rapidly
using postoperative magnetic resonance imaging in all increasing. The development of new equipment for
cases. They created a 4-mm bone hole using a high- fully endoscopic spinal surgery will be key to the
speed drill with a diameter of 3.2 mm, as a larger bone introduction of this procedure. I expect that equipment
hole is required for the treatment of LFS at L5/S1. We manufacturers will partake in the development of this
therefore made an approximately 10 mm diameter new surgical approach.
entry hole at the pars interarticularis using a high-speed
drill with a diameter of 3.5 mm. Dezawa et al. pointed Financial support and sponsorship
[5]
out that the disadvantages of PETA are its technically None.
demanding nature and the hand-eye coordination
learning curve, and recommended that PETA should Conflicts of interest
only be attempted after developing significant skill
in standard endoscopic techniques. Du et al. also There are no conflicts of interest.
[9]
used PETA in 7 highly down-migrated LDH cases and
obtained good outcomes. Compared with the treatment Patient consent
of LDH, the treatment of LFS is more difficult, because All involved patients gave their consent forms.
LFS occurs in older patients with combined facet joint
osteoarthritis and disc degeneration. Further refinement Ethics approval
of the technique will make this improved PETA available Not applicable.
to spine surgeons who treat such patients.
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Mini-invasive Surgery ¦ Volume 1 ¦ March 31, 2017 5