Unilateral Biportal Endoscopy Versus Tubular Microendoscopy in Management of Single Level Degenerative Lumbar Canal Stenosis: A Prospective Study

Abstract

Study design: Prospective clinical study.

Summary of background data: To the authors knowledge, there are no previous prospective studies to test the feasibility of the unilateral biportal endoscopic (UBE) technique in management of lumbar canal stenosis.

Purpose: The study was conducted to compare clinical results of the UBE technique with the tubular microendoscopic (TME) surgery for management of degenerative lumbar canal stenosis.

Methods: One hundred fifty-four cases of single level degenerative lumbar canal stenosis were randomly divided into 2 groups. Each group consisted of 77 cases: one group underwent UBE and the other TME. Clinical outcome was assessed periodically: early postoperative, at 1, 3, and every 6 months for 2 years. Clinical outcome assessment operatives included the Oswestry Disability Index (ODI), Zurich Claudication Questionnaire (ZCQ), and patient satisfaction using Modified Macnab Criteria (MMC). In addition, the admission period, operative time, and estimated blood loss were compared.

Results: In UBE cases, ODI and ZCQ were statistically superior to TME for all periods (P<0.05). For both approaches, values presented progressive improvement until the 24th month. Regarding ODI, UBE and TME had an 84% and 79% success rate, respectively. In ZCQ, UBE and TME had a 79% and 73% success rate, respectively, at the end of the 24th month. Regarding the MMC, UBE and TME had 63% and 29% excellent results, respectively. UBE also has shorter admission period (days: 1.11 vs. 1.28), operative time (minutes: 57.74 vs. 65.31), and less estimated blood loss (mL: 49.47 vs. 53.57).

Conclusions: Given its demanding learning curve, UBE is considered an effective alternative to TME with a higher clinical success rate.

FIGURE 1

Intraoperative pictures for unilateral biportal endoscopic technique depicting (A) 2 small unilateral working channels, (B) endoscopic view of surgical dissector at the midline with bilateral attachments of the ligamentum flavum, and (C) endoscopic view of sublaminar contralateral decompression.

FIGURE 2

Radiographic pictures for a case performed with unilateral biportal endoscopic technique of (A) preoperative and (B) postoperative axial magnetic resonance images cut depicting completed neural decompression, and (C) postoperative axial and (D) sagittal computed tomography scan cut depicting the extent of bony decompression.

FIGURE 3

Intraoperative pictures for tubular microendoscopic surgery (A) depicting the tubular system and working channel, (B) presenting operative view via the working cannula using a diamond high-speed drill for laminotomy, and (C) adjusting the tubular system to work on the contralateral side.

FIGURE 4

Radiographic pictures for a case performed with tubular microendoscopic technique of (A) preoperative axial magnetic resonance images (MRI) cut, (B) postoperative axial MRI cut depicting completed neural decompression utilizing TM, and (C) axial computed tomography cut depicting the extent of bony decompression.

FIGURE 5

Diagram illustrating clinical outcomes over a 24-month period using the Oswestry Disability Index (ODI).

FIGURE 6

Diagram illustrating the clinical outcomes over a 24-month period using the Zurich Claudication Questionnaire (ZCQ).

FIGURE 7

Diagrams representing (A) unilateral biportal endoscopic (UBE) and (B) tubular microendoscopic (TME) success rates regarding Oswestry Disability Index (ODI) and Zurich Claudication Questionnaire (ZCQ). C, The UBE and TME clinical outcomes according to the Modified Macnab Criteria.

FIGURE 8

Illustrations of comparisons between the unilateral biportal endoscopic and tubular microendoscopic regarding (A) admission period, (B) operative time, and (C) estimated blood loss.