Chapter 21 - Minimally invasive spine surgery

Question 1

Minimally invasive lumbar laminectomy pros

Answer 1

interspinous ligament is preserved, unlike in open laminectomy

Access the CONTRALATERAL foramen through your incision, ie if your left foramen is tight, you would make your incision off midline toward the RIGHT then undercut the SP, remove the lamina and ligamentum flavum to access the left

Question 2

Outcomes of MIS discectomy compared with open

Answer 2

Higher incidence of fural tears, slightly lower incidence of wound infection, increased revision surgery rate (increased risk of recurrent disk herniation)

Question 3

Outcomes of minimally invasice laminectomy compared to open

Answer 3

Fewer reoperations for spondylolisthesis and a shorter hospital stay

Question 4

Outcomes of minimally invasive posterior cervical foraminotomy compared with open

Answer 4

trend toward decreased blood loss and shorter hospital stays

equivalent neurologic recovery, complication rate, reduction of neck/arm pain, overall clinical success rate

Question 5

What side to approach from in lateral interbody fusion

Answer 5

Usually performed from the left side: the aorta is more anterior here, and arterial structures are less prone to injury than venous structures

in a multilevel fusion, it is best to approach from the CONCAVE side of the curve

Question 6

What sort of monitoring is needed if going TRANS-psoas approach?

Answer 6

triggered EMG (lumbar plexus monitoring)

Question 7

What levels are most easily accesses through a lateral approach?

Answer 7

L2-3, L3-4

Diaphragm is cephalad, psoas diameter is manageable, iliac crest is caudad, and the iliac bifurcation hasnt happened yet

Question 8

What level is the most challenging to access direct lateral?

Answer 8

L4-5

iliac crest often blocks this level, if this is the case, can often do an oblique lateral or an anterior to psoas lateral approach

Question 9

What level has the greatest risk of lumbar plexus injury in lateral approach to the disc?

Answer 9

L4-5

Question 10

Outcomes of stand-alone interbody fusion cage?

Answer 10

High risk of subsidence and pseudarthrosis

Question 11

Indications for ALIF

Answer 11

1. L5-S1 degen spondylolisthesis
2. L4-5 isthmic spondylolisthesis
3. L5-S1 > L4-5»> or L3-4 single level degen disk disease
4. pseudarthrosis after posterior fusion=

Question 12

What fluoro view is most important for ensuring safety in percutaneous pedicle screw instrumentation

Answer 12

AP

Question 13

Outcomes of posterior percutaneous fusion compared to open

Answer 13

Less blood loss, lower infection rate. No outcome measures to demonstrate superiority of either technique