Clinical Outcomes of Minimally Invasive Posterior Decompression for Lumbar Spinal Stenosis with Degenerative Spondylolisthesis

Clinical effects of arthroscopic-assisted uni-portal spinal surgery and unilateral bi-portal endoscopy on unilateral laminotomy for bilateral decompression in patients with lumbar spinal stenosis: a retrospective cohort study

OBJECTIVE

To investigate the clinical effectiveness of Arthroscopic-assisted Uni-portal Spinal Surgery (AUSS) in the treatment of lumbar spinal stenosis.

METHODS

A total of 475 patients with lumbar spinal stenosis from January 2019 to January 2023 were included in this study. Among them, 240 patients were treated with AUSS (AUSS group); the other 235 patients were treated with unilateral bi-portal endoscopy treatment (UBE group). The differences in surgery-related clinical indicators, pain degree before and after surgery, Oswestry Disability Index (ODI), CT imaging parameters of spinal stenosis, and clinical efficacy were compared between the two groups.

RESULTS

Patients in the AUSS group had a shorter operative time than those in the UBE group, and the length of incision and surgical bleeding were less than those in the UBE group, with statistically significant differences (P < 0.05). Before operation, there was no significant difference in the VAS score of low back pain and leg pain between the two groups (P > 0. 05). After operation, patients in both groups showed a significant reduction in low back and leg pain, and their VAS scores were significantly lower than before the operation (P < 0.05). Three months after surgery, the results of CT re-examination in both groups showed that the spinal stenosis of the patients was well improved, and the measurements of lumbar spinal interspace APDC, CAC, ICA, CAD and LAC were significantly higher than those before surgery (P < 0. 05). Besides, the lumbar function of patients improved significantly in both groups, and ODI measurements were significantly lower than those before surgery (P < 0.05).

CONCLUSION

Both AUSS and UBE with unilateral laminotomy for bilateral decompression can achieve good clinical results in the treatment of lumbar spinal stenosis, but the former has the advantages of simpler operation, shorter operation time, shorter incision length, and less surgical blood loss.

Minimally Invasive Decompression With Noninstrumented Facet Fusion Versus Minimally Invasive Transforaminal Lumbar Interbody Fusion for Stenosis Associated With Grade 1 Lumbar Degenerative Spondylolisthesis

STUDY DESIGN

Retrospective matched cohort study.

SUMMARY OF BACKGROUND DATA

With a growing interest in minimally invasive spine surgery (MIS), the question of which technique is the most advantageous for patients with low-grade degenerative lumbar spondylolisthesis (DLS) still remains unclear.

OBJECTIVE

To compare patient-reported outcomes, perioperative morbidity, and rates of reoperation between MIS decompression with either unilateral noninstrumented facet fusion (MIS-F) or with transforaminal interbody fusion (MIS-T) for grade 1 DLS.

METHODS

Twenty patients who underwent MIS-T and 20 patients with MIS-F were matched based on age, sex, and preoperative ODI, VAS back, and VAS leg. All patients had DLS with at least 4 millimeters of translation on standing radiographs. Exclusion criteria included prior level surgery, multilevel instability, disk impinging on the exiting nerve root, spondylolisthesis from significant facet arthropathy, or foraminal compromise from disk collapse. ODI, VAS back, VAS leg, and patient satisfaction measured by the North American Spine Society questionnaire were tracked at 3, 6, 12, and 24 months postoperatively. Minimum clinically important differences and substantial clinical benefits were calculated.

RESULTS

MIS-F and MIS-T resulted in decreased ODI at 3, 6, and 12 months following the index procedure. Sixty percent of MIS-F and 83% of MIS-T patients reached minimum clinically important difference at 1 year postoperatively; however, using the threshold of 30% ODI reduction from baseline, 67% of MIS-F and 83% MIS-T ( P = 0.25) achieved this goal. Forty-three percent of MIS-F and 59% of MIS-T patients met substantial clinical benefits. Satisfaction at 1 year, measured by a score of 1 or 2 on the North American Spine Society questionnaire, was 64% for MIS-F and 83% for MIS-T.

CONCLUSIONS

MIS-F and MIS-T are effective treatment options for spinal stenosis associated with low-grade DLS. Both techniques result in comparable patient-reported outcomes and satisfaction up to 2 years and have similar long-term reoperation rates. More evidence is required to delineate optimal selection characteristics for MIS-F versus MIS-T.

Progression to fusion after lumbar laminectomy for degenerative lumbar spondylolisthesis: Rate and risk-factors. A national database study

OBJECTIVE

Lumbar laminectomy is often utilized in the treatment of degenerative lumbar spondylolisthesis. Risk factors that contribute to reoperation rates, in particular to progression to fusion, are poorly understood. We aimed to identify rate and risk factors of lumbar fusion surgery following lumbar laminectomy for the treatment of degenerative lumbar spinal spondylolisthesis.

METHODS

Our sample was obtained from the national MarketScan Commercial Claims and Encounters Database. We reviewed patients undergoing lumbar laminectomy for stable degenerative lumbar spondylolisthesis (Grade-1) at one or two levels between January 2007 and December 2016.

RESULTS

A total of 33,681 patients were included. By 2 years after the index operation, 2.48 % of patients had required lumbar fusion surgery. Female sex was associated with lower odds (OR 0.8, 95 %CI 0.7-0.9) of reoperation for fusion. Diabetes (OR 1.2, 95 %CI 1.1-1.4), rheumatoid arthritis (OR 1.5, 95 %CI 1.2-1.7) and clinical presentation with LBP (OR 2.1, 95 %CI 1.6-2.9), lower extremity weakness (OR 1.4, 95 %CI 1.1-1.5), as well as occurrence of a postoperative neurological complications (OR 2.0, 95 %CI 1.1-3.4) increased the odds ratio for requiring fusion surgery within two years after lumbar laminectomy.

CONCLUSION

In this large cross-sectional sample of a national claims database consisting of lumbar laminectomy patients for the treatment of spondylolisthesis, approximately 2.5 % required subsequent lumbar fusion. Several modifiable risk factors for fusion progression were identified, which may guide clinicians in shared decision-making and to help identify patients with elevated post-operative risk providing potential leverage point for prevention.

Decompression alone or decompression with fusion for lumbar spinal stenosis: a randomized clinical trial with two-year MRI follow-up

AIMS

The aims of this study were first, to determine if adding fusion to a decompression of the lumbar spine for spinal stenosis decreases the rate of radiological restenosis and/or proximal adjacent level stenosis two years after surgery, and second, to evaluate the change in vertebral slip two years after surgery with and without fusion.

METHODS

The Swedish Spinal Stenosis Study (SSSS) was conducted between 2006 and 2012 at five public and two private hospitals. Six centres participated in this two-year MRI follow-up. We randomized 222 patients with central lumbar spinal stenosis at one or two adjacent levels into two groups, decompression alone and decompression with fusion. The presence or absence of a preoperative spondylolisthesis was noted. A new stenosis on two-year MRI was used as the primary outcome, defined as a dural sac cross-sectional area ≤ 75 mm² at the operated level (restenosis) and/or at the level above (proximal adjacent level stenosis).

RESULTS

A total of 211 patients underwent surgery at a mean age of 66 years (69% female): 103 were treated by decompression with fusion and 108 by decompression alone. A two-year MRI was available for 176 (90%) of the eligible patients. A new stenosis at the operated and/or adjacent level occurred more frequently after decompression and fusion than after decompression alone (47% vs 29%; p = 0.020). The difference remained in the subgroup with a preoperative spondylolisthesis, (48% vs 24%; p = 0.020), but did not reach significance for those without (45% vs 35%; p = 0.488). Proximal adjacent level stenosis was more common after fusion than after decompression alone (44% vs 17%; p < 0.001). Restenosis at the operated level was less frequent after fusion than decompression alone (4% vs 14%; p = 0.036). Vertebral slip increased by 1.1 mm after decompression alone, regardless of whether a preoperative spondylolisthesis was present or not.

CONCLUSION

Adding fusion to a decompression increased the rate of new stenosis on two-year MRI, even when a spondylolisthesis was present preoperatively. This supports decompression alone as the preferred method of surgery for spinal stenosis, whether or not a degenerative spondylolisthesis is present preoperatively.Cite this article: Bone Joint J 2022;104-B(12):1343-1351.

Prevalence, risk factors, and potential symptoms of hyponatremia after spinal surgery in elderly patients

Old age and spinal surgery significantly increase the risk of postoperative hyponatremia. However, detailed analyses of postoperative hyponatremia after spinal surgery in elderly patients are lacking. Therefore, we retrospectively reviewed the records of 582 consecutive patients aged > 60 years who underwent spinal surgery to evaluate the frequency, risk factors, and symptoms of postoperative hyponatremia after spinal surgery in the elderly population. Postoperative hyponatremia was defined as a postoperative blood sodium level < 135 meq/L at postoperative day (POD)1, POD3, and/or after POD6. A total of 92 (15.8%) patients showed postoperative hyponatremia. On a multivariate analysis, a diagnosis of a spinal tumor/infection, decompression and fusion surgery, and lower preoperative sodium levels were significant independent factors of postoperative hyponatremia (p = 0.014, 0.009, and < 0.001, respectively). In total, 47/92 (51%) cases could have been symptomatic; vomiting was noted in 34 cases (37%), nausea in 19 cases (21%), headache in 14 cases (15%), and disturbances in consciousness, including delirium, in ten cases (21%); all incidences of these symptoms were significantly higher in elderly patients with postoperative hyponatremia than in the matched control group without postoperative hyponatremia (p < 0.05, respectively). Additionally, the length of stay was 2 days longer in patients than in the matched controls (p = 0.002).

Postoperative Physical Therapy Program Focused on Low Back Pain Can Improve Treatment Satisfaction after Minimally Invasive Lumbar Decompression

Patient satisfaction is crucial in pay-for-performance initiatives. To achieve further improvement in satisfaction, modifiable factors should be identified according to the surgery type. Using a prospective cohort, we compared the overall treatment satisfaction after microendoscopic lumbar decompression between patients treated postoperatively with a conventional physical therapy (PT) program (control; n = 100) and those treated with a PT program focused on low back pain (LBP) improvement (test; n = 100). Both programs included 40 min outpatient sessions, once per week for 3 months postoperatively. Adequate compliance was achieved in 92 and 84 patients in the control and test cohorts, respectively. There were no significant differences in background factors; however, the patient-reported pain score at 3 months postoperatively was significantly better, and treatment satisfaction was significantly higher in the test than in the control cohort (−0.02 ± 0.02 vs. −0.03 ± 0.03, p = 0.029; 70.2% vs. 55.4%, p = 0.045, respectively). In the multivariate logistic regression analysis, patients treated with the LBP program tended to be more satisfied than those treated with the conventional program, independent of age, sex, and diagnosis (adjusted odds ratio = 2.34, p = 0.012). Postoperative management with the LBP program could reduce pain more effectively and aid spine surgeons in achieving higher overall satisfaction after minimally invasive lumbar decompression, without additional pharmacological therapy.

Microendoscopic Lumbar Posterior Decompression Surgery for Lumbar Spinal Stenosis: Literature Review

Lumbar spinal stenosis (LSS) is a common disease in the elderly, mostly due to degenerative changes in the lumbar spinal complex. Decompression surgery is the standard surgical treatment for LSS. Classically, total laminectomy—which involves resection of the spinous process, entire laminae and medial facet—has been the standard decompression technique; however, it can cause post-surgical instability. To overcome this disadvantage, various minimally invasive techniques that preserve the stabilization structures of the spine have been developed, and surgeons have begun to re-evaluate decompression surgery from the standpoint of reduced invasiveness and cost. More than two decades have passed since the introduction of microendoscopic spine surgery, and studies continue to shed light on its advantages and limitations as new knowledge becomes available. This article is a narrative review of the available literature, along with authors’ experience, regarding the indications, surgical techniques, clinical outcomes, and limitations/complications of microendoscopic decompression for LSS.