Incidence of subsequent surgical decompression following minimally invasive approaches to treat lumbar spinal stenosis: A retrospective review

BACKGROUND CONTEXT

Surgical decompression is the definitive treatment for managing symptomatic lumbar spinal stenosis; however, select patients are poor surgical candidates. Consequently, minimally invasive procedures have gained popularity, but there exists the potential for failure of therapy necessitating eventual surgical decompression.

PURPOSE

To evaluate the incidence and characteristics of patients who require surgical decompression following minimally invasive procedures to treat lumbar spinal stenosis.

STUDY DESIGN/SETTING

Retrospective review.

PATIENT SAMPLE

Patients who underwent minimally invasive procedures for lumbar spinal stenosis (Percutaneous Image-guided Lumbar Decompression [PILD] or interspinous spacer device [ISD]) and progressed to subsequent surgical decompression within 5 years.

OUTCOME MEASURES

The primary outcome was the rate of surgical decompression within 5 years following the minimally invasive approach. Secondary outcomes included demographic and comorbid factors associated with increased odds of requiring subsequent surgery.

METHODS

Patient data were collected using the PearlDiver-Mariner database. The rate of subsequent decompression was described as a percentage while univariable and multivariable regression analysis was used for the analysis of predictors.

RESULTS

A total of 5278 patients were included, of which 3222 (61.04%) underwent PILD, 1959 (37.12%) underwent ISD placement, and 97 (1.84%) had claims for both procedures. Overall, the incidence of subsequent surgical decompression within 5 years was 6.56% (346 of 5278 patients). Variables associated with a significantly greater odds ratio (OR) [95% confidence interval (CI)] of requiring subsequent surgical decompression included male gender and a prior history of surgical decompression by 1.42 ([1.14, 1.77], p = 0.002) and 2.10 times ([1.39, 3.17], p < 0.001), respectively. In contrast, age 65 years and above, a diagnosis of obesity, and a Charlson Comorbidity Index score of three or greater were associated with a significantly reduced OR [95% CI] by 0.64 ([0.50, 0.81], p < 0.001), 0.62 ([0.48, 0.81], p < 0.001), and 0.71 times ([0.56, 0.91], p = 0.007), respectively.

CONCLUSIONS

Minimally invasive procedures may provide an additional option to treat symptomatic lumbar spinal stenosis in patients who are poor surgical candidates or who do not desire open decompression; however, there still exists a subset of patients who will require subsequent surgical decompression. Factors such as gender and prior surgical decompression increase the likelihood of subsequent surgery, while older age, obesity, and a higher Charlson Comorbidity Index score reduce it. These findings aid in selecting suitable surgical candidates for better outcomes in the elderly population with lumbar spinal stenosis.

Comparison of biportal endoscopic technique and uniportal endoscopic technique in Unilateral Laminectomy for Bilateral Decomprssion (ULBD) for lumbar spinal stenosis

OBJECTIVE

Unilateral laminotomy for bilateral decompression (ULBD) has been adopted widely to treat lumbar spinal stenosis (LSS). The objective of the study is to investigate clinical and radiological outcomes of the biportal endoscopic ULBD (BE-ULBD) and uniportal endoscopic ULBD (UE-ULBD).

METHODS

We collected retrospectively 65 patients' data who met the inclusion criteria (July 2019-June 2021). 33 patients underwent BE-ULBD surgery, and 32 patients underwent the UE-ULBD surgery, and were followed up for at least 1 year. The following preoperative and postoperative outcomes were compared between groups: the visual analog scale (VAS) for pain, the Oswestry disability index (ODI) for nerve function, and modified Macnab criteria for satisfaction, the cross-sectional area of the dural sac (DSCSA), the mean angle of facetectomy.

RESULTS

Age, BMI, gender, levels of involvement and duration of symptoms were not significantly different at baseline in this study. Clinical data showed that postoperative ODI, VAS scores and Modified Macnab Criteria were not statistically different between the two groups. The BE-ULBD group had a shorter operation time than the UE-ULBD group (P < 0.001). Patients in the BE-ULBD group had a larger postoperative expansion of DSCSA expansion postoperatively (85.58 ± 3.16 mm2 VS 71.43 ± 3.35 mm2, P < 0.001) and a larger contralateral facetectomy angle (63.95 ± 3.34° vs 57.80 ± 3.43°, P < 0.001) compared with patients in the UE-ULBD group. There were no statistical differences in the incidence of postoperative complications between the two groups.

CONCLUSION

Both the BE-ULBD and the UE-ULBD yielded clinical improvement in terms of pain and stenosis symptoms. The BE-ULBD technique has the advantages of the shorter operation time, larger DSCSA expansion and larger contralateral facetectomy angle.

Indications for and Outcomes of Three Unilateral Biportal Endoscopic Approaches for the Decompression of Degenerative Lumbar Spinal Stenosis: A Systematic Review

Objective: In this systematic review, we summarized the indications for and outcomes of three main unilateral biportal endoscopic (UBE) approaches for the decompression of degenerative lumbar spinal stenosis (DLSS). Methods: A comprehensive search of the literature was performed using Ovid Embase, PubMed, Web of Science, and Ovid’s Cochrane Library. The following information was collected: surgical data; patients’ scores on the Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and Macnab criteria; and surgical complications. Results: In total, 23 articles comprising 7 retrospective comparative studies, 2 prospective comparative studies, 12 retrospectives case series, and 2 randomized controlled trials were selected for quantitative analysis. The interlaminar approach for central and bilateral lateral recess stenoses, contralateral approach for isolated lateral recess stenosis, and paraspinal approach for foraminal stenosis were used in 16, 2, and 4 studies, respectively. In one study, both interlaminar and contralateral approaches were used. L4-5 was the most common level decompressed using the interlaminar and contralateral approaches, whereas L5-S1 was the most common level decompressed using the paraspinal approach. All three approaches provided favorable clinical outcomes at the final follow-up, with considerable improvements in patients’ VAS scores for leg pain (63.6–73.5%) and ODI scores (67.2–71%). The overall complication rate was <6%. Conclusions: The three approaches of UBE surgery are effective and safe for the decompression of various types of DLSS. In the future, long-term prospective studies and randomized control trials are warranted to explore this new technique further and to compare it with conventional surgical techniques.

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.

Minimally Invasive Discectomy and Decompression for Lumbar Spine using Tubular Retractor System: Technique, Learning Curve and Outcomes

Objective To study the indications, technical nuances, learning curve, and outcomes associated with minimally invasive tubular discectomy of spine (MITDS) and minimally invasive tubular decompression (MITD) using the tubular retractor system and compare the outcomes with open microdiscectomy and open decompression.

Materials and Methods All patients who underwent MITDS and MITD received a trial of conservative management for 6 weeks prior to surgery. Patients who had undergone open microdiscectomy and open decompression during the same period were used as controls. Operating time, intraoperative blood loss, preop and postop visual analogue scale (VAS) scores, preop and postop Oswestry disability index (ODI) scores, duration of hospital stay, complications, and need for redo surgery were analyzed.

Results Thirty-two patients who underwent MITDS and 8 patients who underwent MITD were compared with an equal number of patients who underwent open microdiscectomy and open decompression, respectively. MITDS and MITD were associated with shorter hospital stay. Short-term pain outcome was better in MITDS and MITD group, although it was not statistically significant in MITD group. Functional outcome measured in terms of ODI at 6 months was not statistically significant between minimally invasive and open procedures.

Conclusion Both MITDS and MITD have a significant learning curve and have a distinct advantage of shorter hospital stay. MITDS has the distinct advantage of better short-term pain relief compared with open procedures. For MITD, comparison of short-term pain relief requires a larger sample size. To establish long-term advantages of MITDS and MITD, larger sample size and long-term follow-up are needed.

Microendoscope-Assisted Versus Open Posterior Lumbar Interbody Fusion for Lumbar Degenerative Disease: A Multicenter Retrospective Cohort Study

Background and objectives: Minimally invasive surgery has become popular for posterior lumbar interbody fusion (PLIF). Microendoscope-assisted PLIF (ME-PLIF) utilizes a microendoscope within a tubular retractor for PLIF procedures; however, there are no published reports that compare Microendoscope-assisted to open PLIF. Here we compare the surgical and clinical outcomes of ME-PLIF with those of open PLIF. Materials and Methods: A total of 155 consecutive patients who underwent single-level PLIF were registered prospectively. Of the 149 patients with a complete set of preoperative data, 72 patients underwent ME-PLIF (ME-group), and 77 underwent open PLIF (open-group). Clinical and radiographic findings collected one year after surgery were compared. Results: Of the 149 patients, 57 patients in ME-group and 58 patients in the open-group were available. The ME-PLIF procedure required a significantly shorter operating time and involved less intraoperative blood loss. Three patients in both groups reported dural tears as intraoperative complications. Three patients in ME-group experienced postoperative complications, compared to two patients in the open-group. The fusion rate in ME-group at one year was lower than that in the open group (p = 0.06). The proportion of patients who were satisfied was significantly higher in the ME-group (p = 0.02). Conclusions: ME-PLIF was associated with equivalent post-surgical outcomes and significantly higher rates of patient satisfaction than the traditional open PLIF procedure. However, the fusion rate after ME-PLIF tended to be lower than that after the traditional open method.

Comparision of biportal endoscopic and microscopic decompression in treatment of lumbar spinal stenosis: A comparative study protocol

BACKGROUND

Microscopic bilateral decompression (MBD) has been suggested as an alternative to open laminectomy and fusion. Recently, percutaneous biportal endoscopic decompression (PBED) has begun to attract attention. The purpose of this retrospective study was to evaluate postoperative pain, functional disability, symptom reduction and satisfaction, and specific surgical parameters between the MBD and PBED techniques in patients with lumbar spinal stenosis (LSS).

METHODS

A retrospective review of LSS patients performed with MBD or PBED technique between May 2015 and June 2018 was conducted. Institutional review board approval in People's Hospital of Ningxia Hui Nationality Autonomous Region was obtained prior to conducting chart review and analysis. We received informed consent from all patients before surgery. The primary outcomes assessed were the preoperative to postoperative changes in leg/back pain and disability/function, patient satisfaction with the procedure, and postoperative quality of life. The secondary outcomes including duration of postoperative hospital stay, time to mobilization, postoperative analgesic use, complication rates, and baseline patient characteristics were prospectively collected.

RESULTS

The hypothesis was that the PBED technique would achieve better clinical outcomes as compared to the MBD technique in LSS.

Feasibility and Outcomes of Tubular Decompression in Extreme Stenosis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To report the feasibility, nuances, technical tips as well as outcomes of managing single-level grade D (extreme stenosis) and to compare the outcomes with nonextreme stenosis using the tubular retractor system.

SUMMARY OF BACKGROUND DATA

Minimally invasive decompression in extreme stenosis is a challenge due to technical difficulty, feasibility of adequate decompression, and a steep learning curve.

METHODS

Consecutive patients from January 2007 to January 2017 presenting with neurogenic claudication secondary to single-level spinal stenosis operated using tubular retractors were included in the study. The patients were divided into two groups; extreme-stenosis and nonextreme stenosis. The outcomes of surgery were evaluated and compared using visual analogue score (VAS) for leg and back pain, Oswestry disability index (ODI), and MacNab's criteria.

RESULTS

A total of 325 patients (out of 446 patients after excluding the multilevel cases) fulfilled the inclusion criteria. One hundred forty patients were cases of extreme stenosis and 185 were nonextreme stenosis. The mean VAS for back and leg pain for extreme stenosis improved from 3.23 ± 1.30 to 2.15 ± 0.91 and 7.33 ± 0.78 to 1.66 ± 1.03 respectively as compared with nonextreme stenosis where the mean VAS for back and leg pain improved from 3.01 ± 1.15 to 1.86 ± 1.10 and 6.57 ± 1.00 to 1.54 ± 1.12 respectively. The mean ODI changed from 66.47 ± 7.53 to 19.95 ± 2.90 in extreme stenosis as compared with nonextreme stenosis where mean ODI changed from 59.05 ± 5.08 to 19.88 ± 2.67. As per MacNab's criteria 102 (of 120 patients) and 139 (of 157 patients) reported excellent and good outcomes in extreme and nonextreme stenosis respectively.

CONCLUSION

Tubular decompression is feasible in patients with extreme-stenosis with no difference in the outcomes as well as complication rates when compared with a cohort of nonextreme stenosis.

LEVEL OF EVIDENCE

3.

Clinical and radiological outcomes between biportal endoscopic decompression and microscopic decompression in lumbar spinal stenosis

BACKGROUND CONTEXT

Numerous minimal invasive techniques treating lumbar spinal stenosis have been introduced. Clinical results using biportal endoscopic spinal surgery has recently been introduced as a treatment option for lumbar spinal stenosis. The purpose of this study was to compare the clinical and radiologic outcome between microscopic unilateral laminotomy bilateral decompression and biportal endoscopic unilateral laminotomy bilateral decompression in patients with degenerative lumbar spinal stenosis.

METHOD

A total of 89 patients were evaluated for this study. Only single-level patients were enrolled for accurate comparison. Patients that underwent biportal endoscopic surgery were assigned to Group A, and patients that underwent microscopic surgery were designated Group B. Clinical outcomes were evaluated using modified Macnab criteria, Oswestry Disability Index, and Visual Analog Scale. Postoperative complications were checked until final follow up. Plain radiographs before and after surgery were compared to analyze the change of alignment.

RESULT

There was a significant difference between Group A and B in VAS of back on postoperative 2 months. Other clinical measurements except for postoperative 2 months VAS of back showed no significant difference. There were no significant differences between Group A and Group B regarding preoperative and postoperative radiological findings.

CONCLUSION

Two different decompression techniques preserve the spinal structure and exhibit a favorable clinical outcome and have the advantage of not causing postoperative instability in the short term follow up. Biportal endoscopic surgery may leads to less postoperative back pain than microscopic surgery, which may allow early ambulation and shorter hospitalization period.

Are There Differences Between Patients with Extreme Stenosis and Non-extreme Stenosis in Terms of Pain, Function or Complications After Spinal Decompression Using a Tubular Retractor System?

BACKGROUND

Micro-tubular decompression in extreme lumbar spinal stenosis is challenging because it is technically difficult to achieve adequate decompression. Whether the results of micro-tubular decompression related to pain, function, and complications in lumbar spinal stenosis of the extreme and non-extreme varieties are different has not yet been conclusively established.

QUESTIONS/PURPOSES

Are there differences between patients with extreme stenosis and non-extreme stenosis in terms of (1) VAS back or leg pain, (2) Oswestry Disability Index (ODI), or (3) complications when they were treated with spinal decompression using a tubular retractor system?

METHODS

Between January 2007 and January 2017, one surgeon performed 325 single-level lumbar micro-tubular decompressions without fusion. Of those, 43% (140 of 325) had extreme stenosis (defined as the absence of cerebrospinal fluid signal and a grey homogeneous dural sac with unrecognizable rootlets and posterior epidural fat in T2 weighted axial MRI image) and the rest had non-extreme stenosis. During this time, we used tubular retractors for these procedures in patients with simple lumbar spinal stenosis who had persistent symptoms despite conservative treatment for neurogenic claudication. No alternate form of decompression was performed in the study period. Patients with complex lumbar spinal stenosis associated with a deformity or instability who were treated with instrumented fusion were excluded. A total of 14% (20 of 140) patients in the extreme stenosis group and 15% (28 of 185) patients in the non-extreme stenosis group were lost to follow-up before 2 years; the remaining 120 patients with extreme stenosis and 157 patients with non-extreme stenosis were analyzed at a mean follow-up of 33 ± 5 months in this retrospective, comparative study. The groups were not different at baseline in terms of preoperative VAS score for back pain, age, gender, BMI or the percentage who had diabetes or who smoked. However, patients with extreme stenosis had higher preoperative ODI scores and higher preoperative VAS score for leg pain compared with the non-extreme group. There was a higher proportion of men in the non-extreme stenosis group (56% [104 of 185] versus 50% [71 of 140]; p = 0.324). Study endpoints were VAS score for leg and back pain, ODI, and complications, all of which were ascertained by chart review. With the numbers available, we could detect with 80% power at p < 0.05 a difference of 0.93 cm of 10 cm on a 10-cm VAS scale for VAS leg pain; a difference of 1.00 cm of 10 cm on a 10-cm VAS scale for VAS back pain and a difference of 2.12 cm of 100 cm on a 100-cm ODI scale.

RESULTS

In terms of pain, both groups improved after surgery, but there was no between-group difference in terms of the VAS scores at the most recent follow-up. VAS back pain improved from a mean of 3 ± 1 to 2 ± 1 in the extreme stenosis group and from 3 ± 1 to 1 ± 1 in the non-extreme stenosis group (p = 0.904); VAS leg pain improved from 7 ± 1 to 1 ± 1 versus 6 ± 1 to 1 ± 1, respectively (p = 0.537). ODI scores likewise improved in both groups, with no between-group difference in the ODI scores at latest follow-up (66 ± 7 to 19 ± 2 in the extreme stenosis group versus 59 ± 5 to 19 ± 2 in the non-extreme stenosis group (p = 0.237). Complications in the group with extreme stenosis occurred in six patients (incidental dural tears in two patients, urinary retention in three patients, and Syndrome of Inappropriate Anti Diuretic Hormone secretion (SIADH) in one patient); complications in the non-extreme stenosis occurred in two patients (incidental dural tears in two patients).

CONCLUSIONS

The results in terms of improvement in VAS for leg and back pain and ODI scores were not different between patients with extreme and non-extreme stenosis. Micro-tubular decompression can be thus considered an alternative for patients with extreme stenosis. Future studies, ideally multicentre, comparative trials, are needed to confirm our preliminary results.

LEVEL OF EVIDENCE LEVEL

III, therapeutic study.

Endoscopic Lumbar Surgery: The State of the Art in 2019

This study was aimed to provide a brief historical perspective to facilitate appreciation of current techniques, describe outcomes of endoscopic lumbar surgery relative to those of existing techniques, and identify topics in need of study and future directions for the field of endoscopic lumbar surgery. Using the PubMed database, a comprehensive search was conducted to identify peer-reviewed English language articles pertaining to endoscopic lumbar surgery. Lack of focus on pertinent techniques or lack of outcome measures constituted exclusion criteria. A majority of included articles were published from 2015–2019. A context with which to appreciate the application of endoscopic lumbar techniques is established. An abundance of case series and several recent comparison studies have documented the benefits and potential pitfalls of these methods in the past two decades. The advantages of endoscopic lumbar spine surgery are widely touted to include reduced perioperative morbidity, including blood loss, operative time and immediate postoperative recovery, minimal structural trauma resulting from surgery, generally positive patient report outcome scores and the potential to contain costs. Additional high-quality research assessing outcomes of endoscopic lumbar surgery are certainly needed and currently expected given the rapid expansion of the field in recent years.

ANALYSIS OF POSTOPERATIVE OUTCOMES OF DEGENERATIVE DISEASES OF THE LUMBOSACRAL JUNCTION

ABSTRACT Objective: The article presents an analysis of the clinical efficacy and causes of unsatisfactory outcomes of surgical treatment in patients with degenerative diseases of the lumbosacral junction of the spine. Methods: Patients were allocated to one of three groups, depending on the method of surgical intervention on the lumbosacral junction: 1) (n=352) - operated by the method of microsurgical discectomy; 2) (n=83) - operated with the use of artificial IVD prostheses; 3) (n = 183) - operated with the use of interbody fusion and posterior rigid stabilization. To investigate the causes of unsatisfactory outcomes, a correlation analysis was conducted of long-term clinical outcomes with preoperative instrumental parameters in the operated segment, surgical tactics used, and the development of complications. Results: It is determined that long-term “good” clinical outcomes are associated with individual preoperative parameters of the lumbosacral junction of the spine - linear displacement, sagittal angulation, height of the interbody space, degree of IVD degeneration by ADC. Conclusion: In degenerative diseases of the lumbosacral junction of the spine, the detailed analysis of long-term clinical outcomes enable the identification of the causes that affect the development of unsatisfactory outcomes, which are individual morphostructural changes in the lower lumbar segment: the amplitude of the segmental angle, the angle of the lumbar lordosis, the degree of linear displacement of the vertebrae, the height of the interbody space, and ADC. Complex clinical and instrumental analysis enabled us to determine possible surgical tactics. Level of Evidence II; Prognostic Studies— Investigating the Effect of a Patient Characteristic on the Disease Outcome.

Comparative study of two spinous process (SP) osteotomy techniques for posterior decompression surgery in lumbar spinal stenosis: SP base versus splitting osteotomy

PURPOSE

To compare the postoperative clinical and radiological outcomes of the SP base osteotomy versus SP splitting techniques for PD for treating LSS.

METHODS

Of 139 patients who underwent PD surgery for LSS, 97 who met the study criteria were enrolled in the study. Group A comprised 53 patients who underwent SP base osteotomy, and group B included 44 patients who underwent SP splitting osteotomy. The primary study endpoint was intensity of lower back pain (LBP) and pain radiation to the lower extremities measured with the visual analogue scale (VAS). Secondary endpoints included (1) clinical outcomes assessed using Oswestry disability index and 12-short health form questionnaire; (2) surgical outcomes; and (3) procedure-related complications.

RESULTS

LBP was more or less greater in SP base osteotomy group than in SP splitting osteotomy group at postoperative 1 week and 1 year (P = 0.04 and 0.03), but radiating pain was no significant difference between the groups throughout the 1-year follow-up period. One year after the surgery, the fusion rate at the osteotomized site was significantly greater in SP splitting osteotomy group (77%) than in SP base osteotomy group (55%) (P = 0.03). Clinical outcomes, surgical outcomes, and complications did not differ significantly between groups during follow-up times.

CONCLUSIONS

The two SP osteotomy techniques offer excellent clinical and radiological outcomes at least for the first year after the surgery. In fusion rate at the osteotomized SP site, the SP splitting technique was superior to the SP base osteotomy technique. These slides can be retrieved under Electronic Supplementary Material.

Comparison of the Minimally Invasive and Conventional Open Surgery Approach in the Treatment of Lumbar Stenosis: A Systematic Review and a Meta-Analysis

Introduction: Minimally invasive surgery (MIS) is increasingly used in the treatment of lumbar stenosis. However, it is still not clear if the employment of minimally invasive surgical techniques can achieve superior clinical outcomes compared to standard open laminectomy. Materials and Methods: An extensive literature review regarding the clinical outcome, safety, and efficiency of MIS and standard open surgery (OS) in the treatment of lumbar stenosis was conducted on Medline, Cochrane, EMBASE, and Google Scholar databases up to 19 August 2016. Results: Sixteen studies that enrolled a total of 1580 patients with surgically-indicated lumbar stenosis were identified; 793 patients underwent MIS and 787 patients underwent conventional OS. No significant difference was found in the improvement of Oswestry Disability Index (ODI) (P = 0.718) and operation time (P = 0.322) between patients from different treatment groups. MIS was associated with better visual analogue scale (VAS) for back pain (P = 0.01), shorter length of hospital stay (P <0.001), and lower blood loss (P <0.001). Conclusion: Our findings indicate that both MIS and standard OS can effectively manage patients with lumbar stenosis and lead to comparable clinical outcomes. Further studies are necessary to evaluate MIS with different types of conventional surgery for lumbar stenosis. Key words: Back pain, Laminectomy

Iatrogenic spondylolisthesis following laminectomy for degenerative lumbar stenosis: systematic review and current concepts

OBJECT Decompression without fusion for degenerative lumbar stenosis is an effective treatment for both the pain and disability of neurogenic claudication. Iatrogenic instability following decompression may require further intervention to stabilize the spine. The authors review the incidence of postsurgical instability following lumbar decompression, and assess the impact of surgical technique as well as study design on the incidence of instability. METHODS A comprehensive literature search was performed to identify surgical cohorts of patients with degenerative lumbar stenosis, with and without preexisting spondylolisthesis, who were treated with laminectomy or minimally invasive decompression without fusion. Data on patient characteristics, surgical indications and techniques, clinical and radiographic outcomes, and reoperation rates were collected and analyzed. RESULTS A systematic review of 24 studies involving 2496 patients was performed, assessing both open laminectomy and minimally invasive bilateral canal enlargement. Postoperative pain and functional outcomes were similar across the various studies, and postoperative radiographie instability was seen in 5.5% of patients. Instability was seen more frequently in patients with preexisting spondylolisthesis (12.6%) and in those treated with open laminectomy (12%). Reoperation for instability was required in 1.8% of all patients, and was higher for patients with preoperative spondylolisthesis (9.3%) and for those treated with open laminectomy (4.1%). CONCLUSIONS Instability following lumbar decompression is a common occurrence. This is particularly true if decompression alone is selected as a surgical approach in patients with established spondylolisthesis. This complication may occur less commonly with the use of minimally invasive techniques; however, larger prospective cohort studies are necessary to more thoroughly explore these findings.

Unilateral tubular approach for bilateral laminotomy: effect on ipsilateral and contralateral buttock and leg pain

PURPOSE

Tubular laminotomy is an effective procedure for treatment of lumbar spinal stenosis (LSS) and lateral recesses stenosis. Most surgeons familiar with the procedure agree that the tubular approach appears to afford a more complete decompression of the contralateral thecal sac and nerve root, as compared to the ipsilateral approach. With this study we sought to answer the question whether this is reflected in clinically significant differences between the ipsilateral and contralateral side pain improvements.

METHODS

In a retrospective case study, patients with LSS and lateral recesses stenosis who started out with VAS scores that were similar on the right and left side were included. All patients underwent a tubular (MIS) "over the top" laminotomy from a unilateral approach and through one incision. Surgeries were performed by a single surgeon in a single center. At the last follow-up, the extent of VAS score improvement on the approach (ipsilateral) side was compared to that of the contralateral side.

RESULTS

Thirty-three patients were included in. At the latest follow-up of 25.8 ± 3.4 months, there were statistically significant improvements in ODI and back VAS scores (p = 0.002 and p < 0.0001, respectively). In addition, buttock VAS scores were significantly improved both on the ipsilateral and the contralateral side (p < 0.001, and p = 0.001, respectively). Similarly, leg VAS scores were improved significantly on both sides (p < 0.001, and p = 0.001, respectively). There were no statistically significant differences between the extent of pain improvement on the ipsilateral and the contralateral side.

CONCLUSIONS

MIS tubular laminotomy through a unilateral approach results in clinically effective bilateral decompression of LSS and lateral recesses, regardless of the approach side.

Preoperative retrolisthesis as a risk factor of postdecompression lumbar disc herniation

OBJECT

In this study, the authors aimed to identify specific risk factors for postdecompression lumbar disc herniation (PDLDH) in patients who have not undergone discectomy and/or fusion.

METHODS

Between 2007 and 2012, 493 patients with lumbar spinal stenosis underwent bilateral partial laminectomy without discectomy and/or fusion in a single hospital. Eighteen patients (herniation group [H group]: 15 men, 3 women; mean age 65.1 years) developed acute sciatica as a result of PDLDH within 2 years after surgery. Ninety patients who did not develop postoperative acute sciatica were selected as a control group (C group: 75 men, 15 women; mean age 65.4 years). Patients in the C group were age and sex matched with those in the H group. The patients in the groups were also matched for decompression level, number of decompression levels, and surgery date. The radiographic variables measured included percentage of slippage, intervertebral angle, range of motion, lumbar lordosis, disc height, facet angle, extent of facet removal, facet degeneration, disc degeneration, and vertebral endplate degeneration. The threshold for PDLDH risk factors was evaluated using a continuous numerical variable and receiver operating characteristic curve analysis. The area under the curve was used to determine the diagnostic performance, and values greater than 0.75 were considered to represent good performance.

RESULTS

Multivariate analysis revealed that preoperative retrolisthesis during extension was the sole significant independent risk factor for PDLDH. The area under the curve for preoperative retrolisthesis during extension was 0.849; the cutoff value was estimated to be a retrolisthesis of 7.2% during extension.

CONCLUSIONS

The authors observed that bilateral partial laminectomy, performed along with the removal of the posterior support ligament, may not be suitable for lumbar spinal stenosis patients with preoperative retrolisthesis greater than 7.2% during extension.

Irrigation endoscopic decompressive laminotomy. A new endoscopic approach for spinal stenosis decompression

BACKGROUND CONTEXT

The classic surgical treatment of spinal stenosis involves bilateral dissection of paraspinal muscles to expose all the involved levels, wide laminectomy, and medial facetectomy and foraminotomy. The surgical morbidity of the procedure is further magnified by being more common in elderly with associated medical comorbidities and being usually global involving multiple levels. To address this problem, several less invasive techniques have been introduced over the past decade including the microendoscopic decompression.

PURPOSE

The aim was to describe and evaluate a new endoscopic technique for lumbar spinal canal decompression named irrigation endoscopic decompressive laminotomy.

STUDY DESIGN

This was a technical report.

PATIENT SAMPLE

One hundred four consecutive patients suffering from neurogenic claudication and resistant to 3 months of conservative management were included in the study. Grade I degenerative spondylolisthesis and degenerative scoliosis were not considered a contraindication. Patients with segmental instability and predominant low back pain were excluded.

OUTCOME MEASURES

Primary outcome measures included the final functional outcome using modified Macnab criteria and the Oswestry Disability Index (ODI). In addition, the operative time and complication rate have been evaluated. Secondary outcome measures included the evaluation of the early postoperative course using visual analog scale for postoperative incisional pain, time for ambulation, and length of hospital stay.

METHODS

Two 0.5-cm portals were used, one for the endoscope and the other for instruments. For every additional level, one portal is added. The endoscope and instruments are directly placed over the surface of lamina without any dissection, and saline under pump pressure is used to open a potential working space. Unilateral laminotomy/laminectomy is performed according to the severity of stenosis, followed by bilateral decompression beneath the midline structures.

RESULTS

Mean follow-up period was 28 months. The final outcome was excellent in 63%, good in 24%, fair in 9%, and poor in 4%. The preoperative ODI dropped from a mean of 64.2±10.0 to 23.1±20.8 postoperatively. Complications were limited to six cases of dural tear, which required no open conversion.

CONCLUSIONS

Irrigation endoscopic decompressive laminotomy allows the surgeon to safely perform effective central and foraminal decompression resulting in satisfactory midterm clinical results. Substituting long surgical incisions with 0.5-cm stabs and direct placement of instruments without dissection or dilatation could result in an improved postoperative course, shortened time for hospitalization, and reduced infection rate. However, still multicenter studies and randomized trials are needed before making final conclusions.

Minimally invasive compared with open lumbar laminotomy: no functional benefits at 6 or 24 months after surgery

BACKGROUND CONTEXT

Comparative studies between open and minimally invasive surgical (MIS) approaches for the treatment of spinal stenosis have mainly investigated immediate postoperative parameters.

PURPOSE

We aimed to compare the postoperative improvements in functional and pain scores between open versus MIS lumbar laminotomy and to describe the complications of each method.

STUDY DESIGN/SETTING

We conducted as retrospective review of prospectively collected data.

PATIENT SAMPLE

We included 113 patients.

OUTCOME MEASURES

Visual analog scale for back and leg pain, Oswestry Disability Index (ODI), the North American Spine Society score on neurogenic symptoms (NS), and average Short Form Health Survey-36 (SF-36) score. Accidental durotomies and patients with reoperations are presented.

METHODS

We obtained a list of patients who underwent either MIS or open unilateral one-level lumbar laminotomy for the treatment of neural foraminal or lateral recess stenosis with unilateral leg NS. Outcome measures are presented at 6 and 24 months postoperatively.

RESULTS

From 2000 to 2008, 113 patients (30 open, 83 MIS) underwent a one-level lumbar laminotomy and had complete postoperative data available for analysis. Between the approaches, there were no differences in baseline demographic data or functional scores. At 6 and 24 months after surgery, there were no differences in improvement in back or leg pain, or improvement in ODI, NS, or SF-36 scores. The MIS group reported greater satisfaction with treatment at 6 months (p=.009) but not at 24 months. Within the MIS group, three patients (3.6%) experienced an inadvertent durotomy and two patients (2.4%) underwent fusion of the operated segment within 24 months.

CONCLUSIONS

Compared with an open approach, MIS lumbar laminotomy gave no clear advantages in longer term functional or pain scores. The MIS group also had patients with inadvertent durotomies and reoperation within 2 years. In any lumbar decompressive surgery, the purported advantages of an MIS approach should be carefully weighed against potential complications. For a relatively simple surgery such as laminotomy, the open approach remains a safe and straightforward option.

Minimally invasive laminectomy for lumbar spinal stenosis in patients with and without preoperative spondylolisthesis: clinical outcome and reoperation rates

OBJECT

Surgical decompression is the intervention of choice for lumbar spinal stenosis (LSS) when nonoperative treatment has failed. Standard open laminectomy is an effective procedure, but minimally invasive laminectomy through tubular retractors is an alternative. The aim of this retrospective case series was to evaluate the clinical and radiographic outcomes of this procedure in patients who underwent LSS and to compare outcomes in patients with and without preoperative spondylolisthesis.

METHODS

Patients with LSS without spondylolisthesis and with stable Grade I spondylolisthesis who had undergone minimally invasive tubular laminectomy between 2004 and 2011 were included in this analysis. Demographic, perioperative, and radiographic data were collected. Clinical outcome was evaluated using the Oswestry Disability Index (ODI) and visual analog scale (VAS) scores, as well as Macnab's criteria.

RESULTS

Among 110 patients, preoperative spondylolisthesis at the level of spinal stenosis was present in 52.5%. At a mean follow-up of 28.8 months, scoring revealed a median improvement of 16% on the ODI, 2.75 on the VAS back, and 3 on the VAS leg, compared with the preoperative baseline (p < 0.0001). The reoperation rate requiring fusion at the same level was 3.5%. Patients with and without preoperative spondylolisthesis had no significant differences in their clinical outcome or reoperation rate.

CONCLUSIONS

Minimally invasive laminectomy is an effective procedure for the treatment of LSS. Reoperation rates for instability are lower than those reported after open laminectomy. Functional improvement is similar in patients with and without preoperative spondylolisthesis. This procedure can be an alternative to open laminectomy. Routine fusion may not be indicated in all patients with LSS and spondylolisthesis.

Outcomes after decompressive laminectomy for lumbar spinal stenosis: comparison between minimally invasive unilateral laminectomy for bilateral decompression and open laminectomy: clinical article

OBJECT

The development of minimally invasive surgical techniques is driven by the quest for better patient outcomes. There is some evidence for the use of minimally invasive surgery for degenerative lumbar spine stenosis (LSS), but there are currently no studies comparing outcomes with matched controls. The object of this study was to compare outcomes following minimally invasive unilateral laminectomy for bilateral decompression (ULBD) to a standard "open" laminectomy for LSS.

METHODS

The authors conducted a prospective, 1:1 randomized trial comparing ULBD to open laminectomy for degenerative LSS. The study enrolled 79 patients between 2007 and 2009, and adequate data for analysis were available in 54 patients (27 in each arm of the study). Patient demographic characteristics and clinical characteristics were recorded and clinical outcomes were obtained using pre- and postoperative Oswestry Disability Index (ODI) scores, visual analog scale (VAS) scores for leg pain, patient satisfaction index scores, and postoperative 12-Item Short Form Health Survey (SF-12) scores.

RESULTS

Significant improvements were observed in ODI and VAS scores for both open and ULBD interventions (p < 0.001 for both groups using either score). In addition, the ULBD-treated patients had a significantly better mean improvement in the VAS scores (p = 0.013) but not the ODI scores (p = 0.055) compared with patients in the open-surgery group. ULBD-treated patients had a significantly shorter length of postoperative hospital stay (55.1 vs. 100.8 hours, p = 0.0041) and time to mobilization (15.6 vs. 33.3 hours, p < 0.001) and were more likely to not use opioids for postoperative pain (51.9% vs. 15.4%, p = 0.046).

CONCLUSIONS

Based on short-term follow-up, microscopic ULBD is as effective as open decompression in improving function (ODI score), with the additional benefits of a significantly greater decrease in pain (VAS score), postoperative recovery time, time to mobilization, and opioid use.

Lumbar spinal stenosis: therapeutic options review

Lumbar spinal stenosis (LSS) functionally impacts significant numbers of Americans per year. Current estimates place the number of Americans suffering from senescent lumbar spinal stenosis at 400,000. The prevalence of this disorder in patients ranging from 60 to 69 years of age is very high. Forty-seven percent of this age group have mild to moderate stenosis, and 19.7% have severe stenosis. As the baby boomer generation gets older, 10,000 individuals attain the age of 65 years every day in United States. LSS is becoming very common and will be a major healthcare issue as the population ages. Although LSS is not life threatening, it can cause substantial disability with limitations to performing daily activities, and thus, the associated negative impact on quality of life (QOL). This article reviews the pathophysiology and current treatment options for LSS, focusing on evidence-based treatment options.

Tubular surgery with the assistance of endoscopic surgery via midline approach for lumbar spinal canal stenosis: a technical note

PURPOSE

We devised a tubular surgery with the assistance of endoscopic surgery via midline approach to the spinal canal to preserve the bilateral facet joints and the paravertebral muscles when treating lumbar spinal canal stenosis. We report details of this operative procedure.

METHODS

A 2-cm incision is made in the skin in the midline of the intervertebral level to be decompressed. The spinous process on the cranial side is partially excised, and incisions along the ligament fiber are made in the midline of the supraspinous and interspinous ligaments to expose the ligamentum flavum. After the lamina and the inferior parts of the bilateral facet joints are adequately excised, the microendoscopic discectomy system is inserted. With this procedure, no muscular tissue is seen in the surgical site. The portal approach is small, but if full advantage is taken of the spinal microendoscope's merits, the bilateral facet joints are preserved and wide decompression of deep parts is possible. The microendoscope is positioned above the spinal canal to provide a good symmetrical field of view to enable easy anatomical orientation.

RESULTS

Bilateral intervertebral joints were satisfactorily preserved in ten patients who received this surgery. All became ambulatory on the day after surgery and the clinical results remained favorable 3 years after the operation.

CONCLUSION

Tubular surgery with the assistance of endoscopic surgery via a midline approach is a minimally invasive surgical procedure with favorable results that enables preservation of paravertebral muscles and bilateral facet joints.

Minimally invasive lumbar decompression for the treatment of spinal stenosis of the lumbar spine

SUMMARY Lumbar spinal stenosis is one of the most common degenerative diseases of the elderly population, and a major cause of debilitating pain and decreased function. Lumbar spinal stenosis is almost always associated with neurogenic claudication characterized as pain worsened by standing or walking and relieved by lumbar flexion or sitting. While initial treatment of lumbar spinal stenosis may involve conservative therapies, as patients become more symptomatic the traditional treatment path has generally led to open laminectomy and other invasive, potentially destabilizing, procedures. More recently, less invasive alternatives to wide laminectomy have been developed. This article describes a new method of percutaneous lumbar decompression for treatment of neurogenic claudication secondary to lumbar spinal stenosis, the minimally invasive lumbar decompression procedure. We review the steps of successfully decompressing the hypertrophic ligamentum flavum and lamina, thereby alleviating pressure on neural structures. This is a major innovation in patient care and a step to reduce risks while minimizing costs.

The microendoscopic decompression of lumbar stenosis: a review of the current literature and clinical results

Lumbar stenosis is a well-defined pathologic condition with excellent surgical outcomes. Empiric evidence as well as randomized, prospective trials has demonstrated the superior efficacy of surgery compared to medical management for lumbar stenosis. Traditionally, lumbar stenosis is decompressed with open laminectomies. This involves removal of the spinous process, lamina, and the posterior musculoligamentous complex (posterior tension band). This approach provides excellent improvement in symptoms, but is also associated with potential postoperative spinal instability. This may result in subsequent need for spinal fusion. Advances in technology have enabled the application of minimally invasive spine surgery (MISS) as an acceptable alternative to open lumbar decompression. Recent studies have shown similar to improved perioperative outcomes when comparing MISS to open decompression for lumbar stenosis. A literature review of MISS for decompression of lumbar stenosis with tubular retractors was performed to evaluate the outcomes of this modern surgical technique. In addition, a discussion of the advantages and limitations of this technique is provided.

Long-term outcome after microendoscopic diskectomy for lumbar disk herniation: a prospective clinical study with a 5-year follow-up

BACKGROUND

Several authors have reported results obtained with the microendoscopic diskectomy (MED) technique, but the long-term outcome has not been described. This report summarizes our clinical experience with the lumbar MED technique with a long-term follow-up period.

OBJECTIVE

To evaluate the efficacy of the MED for lumbar disk herniation and to report long-term outcome and complications (5-year follow-up).

METHODS

One hundred twenty consecutive patients with lumbar disk herniation were treated with the METRx system.We included all types of lumbar herniated disks: contained, not contained, foraminal, and migrated disk herniations. The results were evaluated with the Visual Analog Scale (VAS) pain score, Oswestry Disability Index score, patient satisfaction questionnaire, and modified Macnab criteria.

RESULTS

The average age of patients was 41 years; 65 were men and 55 were women. The most commonly affected level was L5-S1 (54.2%). The follow-up time after surgery was 5 years in all cases. We obtained good or excellent results in 75% of patients and regular results in 18%. Good subjective satisfaction was observed with surgery in 92% of patients. The mean decrease in the Oswestry Disability Index score was 52.8 ± 21.6; the mean decrease in leg VAS score was 6.1 ± 2.3; and the mean decrease in lumbar VAS score was 1.9 ± 3.3. Adjusted mean differences were statistically significant in all cases (P < .05).

CONCLUSION

MED not only reduces the incision, tissue damage, and postoperative period of incapacity but also offers long-term results comparable to those of conventional techniques.

Safety and efficacy of a new percutaneously implantable interspinous process device

Background

Lumbar spinal stenosis is a degenerative disease of the elderly population. Although microsurgical decompression has shown good long-term results, percutaneous techniques could provide an alternative in the presence of significant comorbidities.

Method

Eighty-seven interspinous process decompression devices (In-space; Synthes, Umkirch, Germany) were implanted percutaneously in up to three segments of 50 patients. Outcome was assessed directly after surgery, at 6–8 weeks, and at average follow-up of 1 year (11.8 ± 6 months). Assessment included complications, pain and spinal claudication, neurodeficit, time to recurrence of symptoms, and time to second surgery. Subgroups with additional low back pain at presentation and mild spondylolisthesis were analyzed separately.

Findings

Intraoperative complications were rare (one misplacement and two cases of failed implantation); average operation time was 16.4 ± 12.2 min per segment. Initial response was very good with 72% good or excellent relief of symptoms. After a 1-year follow-up, 42% reported of lasting relief from spinal claudication. Thirteen percent of these complained about lasting or new-onset low back pain. A second surgery had been performed in 22%. Subgroup analysis was performed for patients presenting with additional low back pain and spondylolisthesis patients. No significant differences could be noted between subgroups.

Conclusions

The In-space is a percutaneous treatment option of claudication in patients with lumbar spinal stenosis. Compared with microsurgical decompression surgery, recurrence rate within 1 year is, however, high and the device seems not suitable for the treatment of low back pain. Therefore, the authors suggest that the device should presently be used primarily in controlled clinical trials in order to get more information concerning the optimal indication.