Using the Gill criteria, three patients showed excellent results and
four had good outcomes.
Using a new endoscopic technique to treat patients with
spondylosis-induced lumbar nerve root compression shows promising results,
according to researchers from Japan.
“Although spinal fusion is the gold standard to treat
spondylolisthesis, decompression without fusion can be
effective procedure for certain patients,” Koichi Sairyo, MD, PhD, an
author of the study told Orthopedics Today. “Surgeons should
understand the pathology of the symptom for the patients. Not all patients need
The research appeared in the Journal of Neurosurgery.
Scott D. Boden
Orthopedics Today Spine Section Editor Scott D. Boden, MD,
said that while minimal incision decompression techniques have the potential to
improve patient outcomes, such results should be properly proven
“I believe that such techniques, while exciting, have not yet found
their way into broad use because a meaningful objective improvement in patient
outcomes has yet to be consistently documented that would be sufficient to
justify the increased cost of disposables and increased learning curve for the
surgeon,” Boden told Orthopedics Today. “Instead, some
of the minimally invasive decompression techniques have served as marketing
tactics to attract patients to practices.”
He added, “The possibility of decompression without fusion for
spondylolisthesis patients with only radicular leg pain as proposed by Sairyo
is attractive and the key will be whether good results are maintained with long
term follow up.”
For the procedure, about a one-finger
width skin incision is needed to insert the endoscope.
Images: Sairyo K
Sairyo and his colleagues studied seven patients who were older than 40
years old and underwent endoscopic decompression surgery to treat a total of 10
vertebral levels. Preoperatively, the patients had radiculopathy without low
back pain and no evidence of spinal instability on dynamic radiographs. Four
patients had no evidence of subluxation, and three patients were categorized as
having Meyerding grade I slippage. The patients had a mean follow-up of 11.7
The investigators found no intra- or postoperative complications. Using
the Gill criteria, they discovered that three patients had excellent clinical
outcomes and four patients had good results. They also found that all of the
patients reported a decrease or disappearance of leg pain and returned to daily
activities within 3 weeks. Radiographs at final follow-up also revealed no
increase in slippage in any patient.
Sairyo noted that the technique is minimally invasive. “The skin
incision is about 18 mm and the muscular damage is also minimal [because you
are] using a tubular retractor,” he said.
After making the skin incision, surgeons performed fenestration to
identify the impacted nerve root. They then removed the proximal stump of the
ragged edge of the lesion and cleared away the fibrocartilage mass compressing
the nerve root. They used a CT scan to verify that the proximal stump of the
ragged edge of the lesion was removed.
“To decide the indication and to understand the exact pathology
causing the symptom is the most challenging part,” Sairyo said. “If
the pain is from the disc, this procedure is not effective. They may need
This endoscopic view shows that the
L5 nerve root is completely decompressed.
The procedure is indicated for elderly patients with minimal back pain
and radiculopathy caused by a pseudoarthrotic site of spondylolysis — the
ragged edge. Patients should also have no evidence of instability on
radiographs, Sairyo said.
He noted that there is a learning curve for using the technique.
This preoperative CT scan shows that the
hooked-shaped osteophyte (encircled) has entrapped the nerve root.
Surgeons removed the osteophyte as seen in
this postoperative scan of the same patient.
“Before starting this technique, one must get used to the
microendoscopic discectomy technique to treat herniated nucleus pulposus [and
perform] at least 50 cases,” Sairyo said.
He added, “This technique is possible with a surgical microscope.
The minimally invasive microscopic surgery using a tubular retractor is also
For more information:
- Scott D. Boden, MD, is director of Emory University Spine Center.
He can be reached at 59 Executive Park South, Suite 3000, Atlanta, GA 30329;
email@example.com. He is a consultant to
Medtronic, receives royalties from Medtronic and Osteotech, and his center
receives various funding from Medtronic, Synthes, National Institutes of
Health, Linvatec, Johnson & Johnson, DePuy, a Johnson & Johnson
company, and Wright Medical Technology.
- Koichi Sairyo, MD, PhD, can be reached at the Department of
Orthopedics, Institute of Health Biosciences, The University of Tokushima
Graduate School 3-18-15, Kuramoto, Tokushima 770-8503, Japan; e-mail:
or Sairyo@clin.med.tokushima-u.ac.jp. He has no direct financial
interest in any products or companies mentioned in this article.
- Sairyo K, Katoh S, Sakamaki T, et al. A new endoscopic technique to
decompress lumbar nerve roots affected by spondylolysis. J
Neurosurg. 2003; 98 (Suppl 3): 290-293.