Abstract
Not every patient with painful end-stage degenerative disc disease is a
candidate for instrumented fusion surgery or wants it regardless of whether it is carried
out through open, mini-open, or minimally invasive incisions. The authors were
intrigued by their anecdotal observation that elderly patients with painful vacuum discs
serendipitously found during endoscopic decompression went on to successful fusion
and enjoyed substantial long-term pain relief. Therefore, we investigated the feasibility
of a transforaminal endoscopic decompression and un-instrumented lumbar interbody
fusion procedures with cancellous bone allograft. A total of 29 patients had their
vacuum discs directly visualized with a modified hybrid transforaminal technique
employing procedural components of both the outside-in and the inside-out technique.
Intraoperative endoscopic visualization of a painful, hollow collapsed, rigid
intervertebral disc space allowed grafting it with cancellous allograft chips. In addition
to the two-year radiographic assessment of fusion, patients were evaluated with VAS,
ODI, and modified MacNab criteria. At the final follow-up, mean VAS and ODI scores
reduced from 7.34 ± 1.63 and 50.03 ± 10.64 preoperatively to 1.62 ± 1.741 and 6.69 ±
4.294 postoperatively (p < 0.0001). According to Macnab criteria, excellent and good
clinical outcomes were obtained in 34.5% and 62.1% of patients, respectively. Only
one patient had minimal improvement from “Poor” preoperatively to “Fair”
postoperatively. Computed tomography assessment of interbody fusion at the last
follow-up showed successful fusion in 91.4% of patients. Based on these study
observations, the authors concluded that an un-instrumented interbody fusion by
packing a hollow interspace with cancellous bone allograft chips could be an adjunct to
endoscopic foraminal lateral recess decompression select patients with validated
painful, collapsed, and rigid motion segments.Keywords: Allograft, Endoscopic lumbar decompression, Interbody fusion.