Sufficient Lumbar Lateral Recess Decompression Acquired by Undercutting "Superior Articular Process Neck" Plus Intervertebral Disk Annuloplasty in Percutaneous Transforaminal Endoscopic Surgery.

BACKGROUND Percutaneous transforaminal endoscopic surgery has been used as a surgical measure for lumbar lateral recess stenosis. However, the necessary decompressive range has never been clearly documented in detail. Here, we discuss the effectiveness of a percutaneous transforaminal endoscopic procedure with clearly defined decompressive range. MATERIAL AND METHODS The relevant data were retrospectively collected from a series of degenerative lateral recess stenosis patients who acquired a prospectively designed percutaneous transforaminal endoscopic procedure in our department. The decompressive procedure mainly included undercutting of superior articular process and intervertebral disk annuloplasty. Leg pain and back pain was evaluated using visual analogue scale (VAS). The functional status was assessed using Oswestry disability index (ODI). The clinical results were also evaluated using MacNab criteria. RESULTS From May 2014 to October 2018, a total of 33 patients who met our inclusion criteria were included for analysis. There were no perioperative complications. Leg pain VAS decreased from preoperative score of 6.18±2.38 to final follow-up score of 0.45±1.00 (P<0.01). Back pain VAS decreased from preoperative score of 1.88±2.19 to final follow-up score of 0.64±1.02 (P<0.01). ODI (%) decreased from preoperative score of 47.86±18.15 to final follow-up score of 6.29±6.75 (P<0.01). At the final follow-up, the results of MacNab criteria were excellent in 18 cases (54.55%), good in 14 cases (42.42%), fair in 1 case (3.03%) and poor in 0 cases. None of the patients complained of recurrence of the symptoms during follow-up. CONCLUSIONS Undercutting of "superior articular process neck" plus intervertebral disk annuloplasty is sufficient for lumbar lateral recess decompression in a transforaminal approach.