Minimally invasive spinal decompression surgery in diabetic patients: perioperative risks, complications and clinical outcomes compared with non-diabetic patients' cohort

Minimally Invasive vs. Open Surgery for Lumbar Spinal Stenosis in Patients with Diabetes - A Canadian Spine Outcomes and Research Network Study

STUDY DESIGN

Retrospective cohort.

OBJECTIVES

To compare outcomes of minimally invasive surgery (MIS) vs open surgery (OPEN) for lumbar spinal stenosis (LSS) in patients with diabetes.

METHODS

Patients with diabetes who underwent spinal decompression alone or with fusion for LSS within the Canadian Spine Outcomes and Research Network (CSORN) database were included. MIS vs OPEN outcomes were compared for 2 cohorts: (1) patients with diabetes who underwent decompression alone (N = 116; MIS n = 58 and OPEN n = 58), (2) patients with diabetes who underwent decompression with fusion (N = 108; MIS n = 54 and OPEN n = 54). Modified Oswestry Disability Index (mODI) and back and leg pain were compared at baseline, 6-18 weeks, and 1-year post-operation. The number of patients meeting minimum clinically important difference (MCID) or minimum pain/disability at 1-year was compared.

RESULTS

MIS approaches had less blood loss (decompression alone difference 100 mL, P = .002; with fusion difference 244 mL, P < .001) and shorter length of stay (LOS) (decompression alone difference 1.2 days, P = .008; with fusion difference 1.2 days, P = .026). MIS compared to OPEN decompression with fusion had less patients experiencing adverse events (AEs) (difference 13 patients, P = .007). The MIS decompression with fusion group had lower 1-year mODI (difference 14.5, 95% CI [7.5, 21.0], P < .001) and back pain (difference 1.6, 95% CI [.6, 2.7], P = .002) compared to OPEN. More patients in the MIS decompression with fusion group exceeded MCID at 1-year for mODI (MIS 75.9% vs OPEN 53.7%, P = .028) and back pain (MIS 85.2% vs OPEN 70.4%, P = .017).

CONCLUSIONS

MIS approaches were associated with more favorable outcomes for patients with diabetes undergoing decompression with fusion for LSS.

Does Tobacco Smoking Affect the Postoperative Outcome of MIS Lumbar Decompression Surgery?

BACKGROUND

Tobacco smoking is a major cause of morbidity and mortality worldwide. Several authors reported a significant negative impact of smoking on the outcome of spinal surgeries. However, comparative studies on the effect of smoking on the outcome of minimally invasive (MIS) spinal decompression are rare with conflicting results. In this study, we aimed to evaluate clinical outcomes and postoperative complications following MIS decompression in current and former smoking patients compared to those of non-smoking patients.

METHODS

We used our prospectively collected database to retrospectively analyse the records of 188 consecutive patients treated with MIS lumbar decompression at our institution between November 2013 and July 2017. Patients were divided into groups of smokers (S), previous smokers (PS) and non-smokers (N). The S group and the PS group comprised 31 and 40 patients, respectively. The N group included 117 patients. The outcome measures included perioperative complications, revision surgery and length of stay. Patient-reported outcome measures included a visual analogue scale (VAS) for back pain and leg pain, as well as the Oswestry disability index (ODI) for evaluating functional outcomes.

RESULTS

Demographic variables, comorbidity and other preoperative variables were comparable between the three groups. A comparison of perioperative complications and revision surgery rates showed no significant difference between the groups. All groups showed significant improvement in their ODI and VAS scores at 12 and 24 months following surgery. As shown by a multivariate analysis, current smokers had lower chances of improvement, exceeding the minimal clinical important difference (MCID) in ODI and VAS for leg pain at 12 months but not 24 months postoperatively.

CONCLUSIONS

Our findings show that except for a possible delay in improvement in leg pain and disability, tobacco smoking has no substantial adverse impact on complications and revision rates following MIS spinal decompressions.

Standalone lordotic endoscopic wedge lumbar interbody fusion (LEW-LIF™) with a threaded cylindrical peek cage: report of two cases

We report two cases of a standalone lordotic endoscopic wedge lumbar interbody fusion (LEW-LIF™) with a stress-neutral non-expandable cylindrical threaded polyether ether ketone (PEEK) interbody fusion implant. Patients underwent full-endoscopic transforaminal decompression and fusion for symptomatic lateral recess stenosis due to disc herniation, and hypertrophy of the facet joint complex and ligamentum flavum and no more than grade I spondylolisthesis. Lumbar interbody fusion with cages traditionally calls for posterior supplemental fixation with pedicle screws for added stability. A more simplified version of lumbar decompression and fusion without pedicle screws would allow treating patients suffering from stenosis and instability induced sciatica-type low back and leg pain in an outpatient ambulatory surgery center setting (ASC). This would realize a significant reduction in cost as well as the burden to the patient with decreased postoperative pain and earlier return to function. A 62-year-old female patient had surgery at L4/5 for a 6-year history of worsening right sided sciatica-type leg- and low back pain. Another 79-year-old female had the same surgical management at L4/5 for a 5-year history of unrelenting left-sided spondylolisthesis-related symptoms. Both patients had an uneventful postoperative course until the last available follow-up of 24 weeks with greater than 60% VAS and Oswestry disability index (ODI) reductions. There was no evidence of implant expulsion, subsidence, or postoperative instability. We concluded that standalone outpatient lumbar transforaminal endoscopic interbody fusion with a non-expandable threaded cylindrical cage is feasible, and favorable clinical outcomes provide proof of concept to study long-term clinical outcomes in larger groups of patients.

Subsidence induced recurrent radiculopathy after staged two-level standalone endoscopic lumbar interbody fusion with a threaded cylindrical cage: a case report

We report a case of subsidence induced recurrence of unilateral L5 and S1 radiculopathy six months following a successful staged two-level endoscopic standalone lumbar interbody fusion using the VARILIF-L™ device. The patient was a 64-year-old female who first underwent outpatient endoscopic fusion L4/5 for failed non-operative care of Grade I spondylolisthesis. Within 11 months from the L4/5 index procedure, she developed symptomatic adjacent segment disease stemming from the L5/S1 level. A preoperative computed tomography before the planned L5/S1 endoscopic standalone VARILIF™ fusion 15 months following her L4/5 VARILIF™ procedure revealed fusion at the L4/5 level with minimal subsidence of the VARILIF-L™ implant, and advanced degeneration of the L5/S1 motion segment with lateral recess and foraminal stenosis, reduced posterior disc height, and vacuum disc. The patient underwent uneventful L5/S1 endoscopic standalone fusion using the VARILIF-L™ implant with successful clinical outcome and resolution of back and leg symptoms. Six months after the second endoscopic L5/S1 VARILIF™ procedure she developed recurrent L5 and S1 radiculopathy. Computed tomography showed significant implant subsidence and formation of a large soft tissue bulge on the approach side behind the interbody fusion cage. The subsidence induced subsidence and loss of posterior disc height and the associated recurrence of nerve root compression of the traversing S1 and exiting L5 nerve root. The recurrent radiculopathy was eventually treated with another transforaminal endoscopic decompression which included a more generous foraminoplasty with resection of the remaining superior articular process including a partial S1 pediculectomy and additional resection of the posterior annulus as well as scar and bony tissue that had formed within the axillary hidden zone of Macnab. We concluded that recurrent radiculopathy might occur after standalone lumbar transforaminal endoscopic interbody fusion with an expandable threaded cylindrical cage as a result of vertical and angular subsidence.