WHAT IS ELF?
ELF is a method of enlarging the neuroforamen using minimally invasive spine surgery for the
treatment of
foraminal stenosis.
Endoscopic laser foraminoplasty is a technique using the basic technique of selective endoscopic
discectomy to access the neuroforamina.  Once the cannula is in the neuroforamina, the bulging
disc is excised as in SED, but in addition the facet joint is enlarged using a very high power
Holmium YAG side firing laser and mechanical cutter device to open up the size of the
neuroforamen.  The laser will actually vaporize bone when the laser is set on 80 watt power.

WHO DEVELOPED ELF?
Martin Knight, a surgeon in England was largely responsible for the development of the
technique.  David Casper, MD, an Oklahoma City surgeon is the champion of the technique in
America.  There are very few surgeons performing this technique due to the unusual equipment
and anatomy.  There are no surgical or pain management fellowship programs that train
individuals in this technique.  

ADVANTAGES AND DISADVANTAGES OF ELF:
Using a keyhole portal approach, the endoscope can turn a complex operation requiring excision
of significant amounts of spinal support bone and ligaments into a modest surgical procedure.  
The risks are the same as for selective endoscopic discectomy with the caveat that there may be
more trauma to the nerve due to the acoustic wave effect of the laser when fired close to the
nerve.  Also, in small neuroforamina, it may be difficult to place the cannula into the neuroforamen.
In one study the overall complication rate was 1.6% with no major neurological sequelae.

OUTCOME OF ELF
Aware State Endoscopic Laser Foraminoplasty in thr Treatment of Chronic Lumbar Spondylosis and Failed Back Surgery
Martin T.N. Knight The Spinal Foundation, Arbury Consulting Centre, Manchester Road,
   Study Design. This study evaluates the results of Endoscopic Foraminoplasty on 250 consecutive patients followed for a
minimum of 2 years, reviewed and assessed by an external independent assessor.
   Objectives. The objective has been to assess the clinical outcomes and morbidity following Spinal Probing and
Discography pain source definition and their treatment by Endoscopic Laser Foraminoplasty with decompression of the
foramen, mobilisation and neurolysis of the exiting and transiting nerves and ablation of osteophytes in patients with
Chronic Lumbar Spondylosis (CLS) and Failed Back Surgery (FBS).
   The function of the foramen is a delicate balance between the size of the foraminal boundaries and the status of their
contents.  This balance is easily compromised by pathology, irritation or sensitisation of tethered tissues and abnormal
motion.
Outcome Study Methodology. This prospective study involved “daycase” Endoscopic Laser Foraminoplasty performed on
121 males, and 129 females with an average age of 48 years (21-86 years).  They were followed for an average period of 30
months (26-43 months).  The average preoperative duration of symptoms was 6.1 years (5 -11 years).  75 Patients had had 1
– 3 previous open operations.  19 patients were on narcotic analgesics prior to surgery. At other centres, 142 patients
were evaluated and open surgical procedures were not deemed appropriate or likely to be of benefit.

Outcome Study Results. 97% cohort integrity was maintained at the final follow up.  Back, buttock
and leg pain were separately compared and analysed using the percentage change in Oswestry
Disability Index, and percentage change in visual analogue pain (VAP) scores, a Patient
Satisfaction Scoring Scale and a patient Target Achievement Score. Clinically appreciable change
was observed in 74% patients with back pain, 77% buttock pain, and 75% leg pain. Using a
percentage change in Oswestry Disability Index of 50 or more to determine good and excellent
outcomes, 61% of patients exceeded this score for back pain; 66% for buttock pain; and 65% for
leg pain.  95% patients required no further surgical intervention
Click on pics
below to enlarge


Endoscopic Laser
Foraminoplasty- ELF
Sensory
Nerve DRG
Seen
Through the
Endoscope
Portal In
Neuroforamen
Trephine being used to cut off the
facet joint which is causing
foraminal stenosis.
(fluoroscopically guided)
Drawing of
How ELF is
Performed
ELF Laser on
Facet Joint
Vaporizing
Bone-Red Dot
Is Laser Spot
ELF: Laser on
Facet:
Siginificant Bone
Removal