Clinical Outcomes of Selective Single-Level Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression of Multilevel Lumbar Spinal Stenosis and Risk Factors of Reoperation.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To investigate the usefulness of selective single-level lumbar endoscopic unilateral laminotomy for bilateral decompression (LE-ULBD) in patients with radiological multilevel lumbar spinal stenosis (LSS) and clarify the predictive factors of reoperation. METHODS: A total of 128 patients who underwent LE-ULBD of radiological multilevel LSS were retrospectively examined. Single-level decompression was selected clinically and supplemented radiologically. Clinical outcomes were assessed with the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ), numeric rating scale (NRS), and Macnab criteria (mean follow-up period, 28.6 months [range, 24-63 months]). Stenosis severity was classified as grades M (moderate) and S (severe) based magnetic resonance imaging findings. Multilevel LSS was classified as SS, SM, and MM according to the number of grade S levels. RESULTS: The follow-up rate was 74.2%. All domains of the JOABPEQ and NRS significantly improved during follow-up. The Macnab outcome classification was "excellent" or "good" in 77.9% of the patients. The reoperation rate was 10.2%. None of the patients with unilateral symptoms required reoperation. The SS type was a significant risk factor of reoperation for multilevel LSS with bilateral symptoms. Additional LE-ULBD was performed for all the reoperation with the "excellent" or "good" results of the Macnab criteria in 69% of the patients. CONCLUSIONS: Selective single-level LE-ULBD provided favorable results for multilevel LSS. However, information about the risks of reoperation for multilevel severe stenosis with bilateral symptoms should be shared between surgeons and patients.

Full-Endoscopic Lumbar Discectomy for Recurrent Lumbar Disc Herniation: A Retrospective Study with Patient-Reported Outcome Measures.

INTRODUCTION: Revision surgery for recurrent lumbar disc herniation after surgical treatment is at times challenging due to epidural adhesions and scar. This study aimed to review the clinical results and safety of full-endoscopic lumbar discectomy via interlaminar (FELD-IL) and transforaminal (FELD-TF) approaches for revision surgery. METHODS: We conducted a retrospective study including 52 lumbar disc herniation revision patients (mean age, 51.8 years; male/female, 13/39), with 17 FELD-IL and 35 FELD-TF cases. Complication incidences were assessed by reviewing surgical videos and postoperative magnetic resonance images of nerve decompression outcomes. Patients' responses to Japan Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and numerical rating scales (NRS) for lumbar pain, leg pain, and leg numbness were recorded before and during follow-up. The Wilcoxon-signed rank tests were utilized to compare pre- and postoperative group variables. RESULTS: The average operation time was 33.0 min in FELD-IL and 31.7 min in FELD-TF. Seven FELD-IL cases required lamina excavation with high-speed drill bars for scar tissue dissection from the lamina. Dura injury occurred during the excavation in one case. No complication was noted in the FELD-TF group. Successful decompression of the nerve was achieved in all cases. Complete sets of JOABPEQ and NRS were obtained in 64.5% of FELD-IL and in 82.9% of FELD-TF. The mean follow-up period was 18.6 months. All the subdomain of JOABPEQ and NRS improved significantly postoperative in both groups. There was no difference regarding the improvement of scores between the procedures except NRS for lumbar pain, which was more favorable in FELD-IL. Recurrence of herniation occurred in one patient (6%) after FELD-IL and two patients (6%) after FELD-TF. CONCLUSIONS: Both FELD-IL and FELD-TF are safe and effective revision procedures for recurrent lumbar disc herniation. FELD-TF could be performed employing the same procedure as primary surgery in revisions, regardless of the previous surgical approach.

Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression for Lumbar Spinal Stenosis Provides Comparable Clinical Outcomes in Patients with and without Degenerative Spondylolisthesis.

OBJECTIVE: To investigate and compare the clinical and radiological outcomes of lumbar endoscopic unilateral laminotomy for bilateral decompression (LE-ULBD) for lumbar spinal stenosis (LSS) patients with and without degenerative spondylolisthesis (DS). METHODS: A total of 129 patients who underwent LE-ULBD for single-level LSS were retrospectively reviewed. The patients were classified into 2 groups based on the presence of DS. Clinical outcomes were assessed with the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire and numeric rating scale (NRS) for low back pain, lower limb pain, and lower limb numbness. Scores were obtained at baseline and final follow-up (mean follow-up, 28.6 months [range, 24-63 months]). RESULTS: The follow-up rate was 77.5% (103 patients). All domains of the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire and NRS evaluations significantly improved during the follow-up period in both groups; group differences were not significant except for the postoperative NRS limb numbness score, which was higher in patients with DS. The Macnab outcome classification was excellent or good in 80% of patients without DS and 77.1% of patients with DS. During the follow-up period, the increase of vertebral slip was observed in 31% of the patients with DS that includes vertebral slip progression defined as percent slip >5% in 4% of the patients. The increase of vertebral slip was not related to a clinical outcome. Segmental motion of the affected intervertebral disc did not increase after surgery. CONCLUSIONS: LE-ULBD provides a comparably favorable outcome in LSS patients with and without DS. Postoperative segmental instability did not occur in patients with DS.

Posterolateral Transforaminal Full-Endoscopic Lumbar Discectomy for Foraminal or Extraforaminal Lumbar Disc Herniations.

BACKGROUND: Surgical procedures via the posterior median or paramedian approach for lateral lumbar disc herniation require significant bone resection to reach the herniation. In contrast, posterolateral transforaminal full-endoscopic lumbar discectomy (FELD) allows direct access to the lateral disc herniation. This study aimed to determine the efficacy and safety of this procedure. METHODS: A total of 118 patients who underwent posterolateral transforaminal FELD were retrospectively examined. Data on surgical time, perioperative complications, and reoperation rate were reviewed from the medical records. Clinical evaluations were completed in 78 patients using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and numeric rating scale (NRS) for low back pain, lower limb pain, and lower limb numbness obtained at baseline and during a follow-up of more than 12 months. RESULTS: The mean operative time was 33.9 min. Postoperative transient dysesthesia occurred in 11 of 118 patients (9.3%). No other complications were observed. Reoperation was performed in nine patients (5.9%). All domains of JOABPEQ and NRS significantly improved during the follow-up period. The effectiveness rates of the JOABPEQ for measuring low back pain, lumbar function, walking ability, social life function, and mental health were 70.4%, 46.5%, 62.0%, 59.2%, and 32.4%, respectively. Using the Macnab criteria, excellent or good results were achieved in 52 patients (73%). CONCLUSIONS: Successful clinical results were obtained with a few complications and improvements in the domains of JOABPEQ and NRS. Posterolateral transforaminal FELD for lateral lumbar disc herniations is an effective and safe surgical option with minimal invasiveness and sufficient decompression.

Intra- and inter-operator reproducibility of US point shear-wave elastography in various organs: evaluation in phantoms and healthy volunteers.

PURPOSE: This study was conducted in order to assess the intra- and interoperator reproducibility of shear-wave speed (SWS) measurement on elasticity phantoms and healthy volunteers using ultrasound-based point shear-wave elastography. MATERIALS AND METHODS: This study was approved by the institutional review board. Two operators measured the SWS of five elasticity phantoms and seven organs (thyroid, lymph node, muscle, spleen, kidney, pancreas, and liver) of 30 healthy volunteers with 1.0-4.5 MHz convex (4C1) and 4.0-9.0 MHz linear (9L4) transducers. The phantom measurements were repeated ten times, while the volunteer measurements were performed five times each. Intra- and interoperator reproducibility was assessed. Interoperator reproducibility was also evaluated with the 95% Bland-Altman limits of agreement (LOA). RESULTS: In phantoms, all intraclass correlation coefficients (ICCs) were above 0.90 and the 95% LOA between the two operators were less than ± 18%. In volunteers, intraoperator ICCs were > 0.75 for all regions except the pancreas. Interoperator ICC was above 0.75 for the right lobe of the liver (depth 4 cm) and the kidney, but the 95% LOA was less than ± 25% only for the liver. CONCLUSION: Although excellent in phantoms, interoperator reproducibility was insufficient for all regions in the volunteers other than the right hepatic lobe at a depth of 4 cm. Clinicians should be aware of the 95% LOA when using SWS in patients. KEY POINTS: • Our phantom study indicated a high reproducibility for shear-wave speed (SWS) measurements with point shear-wave elastography (pSWE). • In volunteers, intraoperator reproducibility was generally high, but the interoperator reproducibility was not high enough except for the right hepatic lobe at 4 cm depth. • To evaluate interoperator reproducibility, the 95% limits of agreement (LOA) between operators should be considered in addition to the intraclass correlation coefficient (ICC).

Risk factors for re-recurrent carpal tunnel syndrome in patients undergoing long-term hemodialysis.

The purpose of this study was to evaluate risk factors for re-recurrent carpal tunnel syndrome (CTS) in long-term renal hemodialysis (HD) patients. Fifteen wrists of ten HD patients, follow-up period of minimum seven years after reoperation of CTS, were included in this study. Duration of HD, period from first operation to reoperation, shunt side was involved or not, presence of trigger finger and cervical destructive spondyloarthritis, and operative procedure performed during the reoperation (synovectomy was performed or not) were evaluated. Re-recurrent CTS was identified in four out of 15 wrists (27%). The period from first operation to reoperation, which was 3.8 years in the re-recurrence group and eight years in the no re-recurrence group, and the operative procedure had significant differences (synovectomy groups had no re-recurrence vs. no synovectomy groups had 82% re-recurrence). The results of this study suggested that synovectomy would be necessary for recurrent CTS in HD patients.