Endoscopic lumbar foraminotomy.
Foraminal stenosis frequently causes radiculopathy in lumbar degenerative spondylosis. Endoscopic transforaminal techniques allow for foraminal access with minimal tissue disruption. However, the effectiveness of foraminal decompression by endoscopic techniques has yet to be studied. We evaluate radiographic outcome of endoscopic transforaminal foraminotomies performed at L3-L4, L4-L5, and L5-S1 on cadaveric specimens. Before and after the procedures, three dimensional CT scans were obtained to measure foraminal height and area. Following the foraminotomies, complete laminectomies and facetectomies were performed to assess for dural tears or nerve root damage. L3-L4 preoperative foraminal height increased by 8.9%, from 2.12±0.13cm to 2.27±0.14cm (p<0.01), and foraminal area increased by 24.8% from 2.21±0.18cm(2) to 2.72±0.19cm(2) (p<0.01). At L4-L5, preoperative foraminal height was 1.87±0.17cm and area was 1.78±0.18cm(2). Endoscopic foraminotomies resulted in a 15.3% increase of foraminal height (2.11±0.15cm, p<0.05) and 44.8% increase in area of (2.51±0.21cm(2), p<0.01). At L5-S1, spondylitic changes caused diminished foraminal height (1.26±0.14cm) and foraminal area (1.17±0.18cm(2)). Postoperatively, foraminal height increased by 41.6% (1.74±0.09cm, p<0.05) and area increased by 98.7% (2.08±0.17cm(2), p<0.01). Subsequent inspection via a standard midline approach revealed one dural tear of an S1 nerve root. Endoscopic foraminotomies allow for effective foraminal decompression, though clinical studies are necessary to further evaluate complications and efficacy.
Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA.
Alexander I
AI
Evins
Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA.
Matei A
MA
Banu
Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA.
Innocent
I
Njoku
Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA.
Eric H
EH
Elowitz
Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA.
Roger
R
Härtl
Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA.
Antonio
A
Bernado
Department of Neurological Surgery, University of Washington Medical Center, Seattle, WA, USA. Electronic address: chh9045@uw.edu.
Christoph P
CP
Hofstetter
D004724:Endoscopy / Q000379:methods*; D059526:Foraminotomy / Q000379:methods*; D006801:Humans; D007796:Laminectomy / Q000379:methods*; D008159:Lumbar Vertebrae / Q000601:surgery; D008161:Lumbosacral Region / Q000601:surgery; D011843:Radiculopathy / Q000601:surgery; D013116:Spinal Cord / Q000601:surgery*; D013130:Spinal Stenosis / Q000601:surgery
Decompression; Foraminotomy; Lumbar; Minimally invasive surgery; Spine endoscopy; Stenosis