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

Decompressive Surgery for Lumbar Spinal Stenosis: WFNS Spine Committee Recommendations

Objective

Lumbar spine stenosis is a common disease with a prevalence progressively increasing due to the aging of the population. Despite many papers having been published over the last decades, there still remain many doubts regarding its natural history and appropriate treatment. To overcome these problems and reach some globally accepted recommendations, the World Federation of Neurosurgical Society Spine Committee organized a consensus conference on this topic. This paper describes recommendations about the efficacy of surgical decompression, the difference between surgical techniques, and complications of surgery.

Methods

World Federation of Neurosurgical Society Spine Committee aimed to standardize clinical practice worldwide as much as possible and held a 2-round consensus conference on lumbar spinal stenosis. A team of expert spine surgeons reviewed literature regarding surgical treatment from over the last 10 years, and then drafted and voted on some statements based on the presented literature.

Results

Ten statements were voted. The committee agreed on the effectiveness of surgical decompression in patients with moderate-to-severe symptoms or with neurologic deficits. There was no consensus on the best surgical technique and, in particular, about the equivalence of microscopic techniques and an open approach. Regarding complications, we agreed that the most frequent complications are incidental durotomy and general complications in the elderly.

Conclusions

Surgical decompression represents the treatment of choice for symptomatic lumbar spinal stenosis with a low complication rate. However, which surgical technique is the best is still under debate. Further studies with standardized outcome measures are needed to understand the real complication rate and frequency of different unwanted events.

Two-level percutaneous endoscopic lumbar discectomy for highly migrated upper lumbar disc herniation: A case report

BACKGROUND

The technique of percutaneous endoscopic lumbar discectomy (PELD) as a transforaminal approach has been used to treat highly migrated lower lumbar disc herniations. However, due to the different anatomic characteristics of the upper lumbar spine, conventional transforaminal PELD may fail to remove the highly migrated upper lumbar disc nucleus pulposus. Therefore, the purpose of this study was to describe a novel surgical technique, two-level PELD, for the treatment of highly migrated upper lumbar disc herniations and to report its related clinical outcomes.

CASE SUMMARY

A 60-year-old male presented with a complaint of pain at his lower back and right lower limb. The patient received 3 mo of conservative treatments but the symptoms were not alleviated. Physical examination revealed a positive femoral nerve stretch test and a negative straight leg raise test for the right leg, and preoperative visual analog scale (VAS) score for the lower back was 6 points and for the right leg was 8 points. Magnetic resonance imaging (MRI) demonstrated L2-L3 disc herniation on the right side and the herniated nucleus pulposus migrated to the upper margin of L2 vertebral body. According to physical examination and imaging findings, surgery was the primary consideration. Therefore, the patient underwent surgical treatment with two-level PELD. The pain symptom was relieved and the VAS score for back and thigh pain was one point postoperatively. The patient was asymptomatic and follow-up MRI scan 1 year after operation revealed no residual nucleus pulposus.

CONCLUSION

Two-level PELD as a transforaminal approach can be a safe and effective procedure for highly migrated upper lumbar disc herniation.

The benefit zone of full-endoscopic spine surgery

Minimally invasive spine procedures have undergone rapid development during the last decade. Efforts to decrease muscle crush injuries during prolonged retraction, avoid significant soft tissue stripping and minimize bony resection are surgical principles that are employed to prevent iatrogenic instability and provide patients with decreased post-operative pain and disability. Full-endoscopic spine surgery represents a tool for the spine surgeon to provide targeted access to spinal pathology utilizing these principles. Endoscopic techniques have seen over 30 years of evolution and innovation, however, early iterations of these techniques largely focused on transforaminal lumbar microdiscectomies. Currently, endoscopic techniques are utilized for approaching pathology in the cervical, thoracic and lumbar spine. There has been a growing body of literature that not only confirms the efficacy of these procedures but also underscores the advantages these procedures offer with respect to less morbidity and safer complication profiles. Endoscopic decompressions have been utilized in the settings of degenerative spinal stenosis, spondylolisthesis, scoliosis, previous fusion, tumor and infection. Furthermore, endoscopic interbody fusion has also been utilized in the lumbar spine as technology continues to advance. As technological innovation continues to facilitate reproducible surgical technique and expand the indications for use, we believe that endoscopic spine surgical techniques will provide surgeons with a more powerful and less morbid approach to spinal pathology that ultimately elevates the standard of care when treating our patients. We present a brief review of the history of endoscopic spine surgery, an overview of current techniques and review current outcomes of endoscopic spine surgical procedures in the context of an invasiveness/complexity index to elucidate the benefit zone of these newer techniques.

Comparison of full-endoscopic and minimally invasive decompression for lumbar spinal stenosis in the setting of degenerative scoliosis and spondylolisthesis

OBJECTIVE

The management of lumbar spinal stenosis (LSS) with concurrent scoliosis and/or spondylolisthesis remains controversial. Full-endoscopic unilateral laminotomy for bilateral decompression (ULBD) facilitates neural decompression while preserving stabilizing osseoligamentous structures and may be uniquely suited for the treatment of LSS with concurrent mild to moderate degenerative deformity. The safety and efficacy of full-endoscopic versus minimally invasive surgery (MIS) ULBD in this patient population is studied here for the first time.

METHODS

A retrospective analysis of prospectively collected data was conducted on 45 consecutive LSS patients with concurrent scoliosis (≥ 10° coronal Cobb angle) and/or spondylolisthesis (≥ 3 mm). Patient demographics, operative details, complications, and imaging characteristics were reviewed. Outcomes were quantified using back and leg visual analog scale (VAS) scores and the Oswestry Disability Index (ODI) at 2 weeks, 3 months, and 1 year.

RESULTS

A total of 26 patients underwent full-endoscopic and 19 underwent MIS-ULBD with an average follow-up period of 12 months. The endoscopic cohort experienced a significantly shorter hospital length of stay (p = 0.014) and fewer adverse events (p = 0.010). Both cohorts experienced significant improvements in VAS and ODI scores at all time points (p < 0.001), but the endoscopic cohort demonstrated significantly better early ODI scores (p = 0.024).

CONCLUSIONS

Endoscopic and MIS-ULBD result in similar functional outcomes for LSS with mild to moderate deformity, while the endoscopic approach demonstrates a favorable rate of complications. Further studies are required to better delineate the characteristics of spinal deformities amenable to this approach and the durability of functional results.

Comparative analysis of three types of minimally invasive decompressive surgery for lumbar central stenosis: biportal endoscopy, uniportal endoscopy, and microsurgery

OBJECTIVE

Recently, minimally invasive unilateral laminotomy with bilateral decompression (ULBD) has been performed for lumbar stenosis using endoscopic approaches. The object of this retrospective study was to compare the clinical and radiological outcomes of three types of minimally invasive decompressive surgery: microsurgery, percutaneous uniportal endoscopic surgery, and percutaneous biportal endoscopic surgery.

METHODS

In the period from March 2016 to December 2017, minimally invasive ULBD was performed using microscopy, a uniportal endoscopic approach, or a biportal endoscopic approach to treat lumbar canal stenosis. Patients were classified into three groups based on the surgery they had undergone. The angle of medial facetectomy area and postoperative dural expansion were measured using MR images. The visual analog scale (VAS) score for leg and back pain, Oswestry Disability Index (ODI), operation time, and complications were assessed. Clinical and radiological parameters were compared among the three groups.

RESULTS

There were 33 patients in the microscopy group, 37 in the biportal endoscopy group, and 27 in the uniportal endoscopy group. Preoperatively stenotic dural areas were significantly expanded in each of the three groups after surgery (p < 0.05). Mean dural expansion in the uniportal endoscopy group was significantly lower than that in the microscopy or biportal endoscopy group (p < 0.05). The mean angle of the facetectomy in the biportal endoscopic group was significantly lower than that in the microscopic group or uniportal endoscopic group (p < 0.05). On the 1st day after surgery, the VAS score for back pain was significantly higher in the microscopic group than in the uniportal or biportal endoscopic group (p < 0.05). However, there were no significant differences in the VAS score for back pain, VAS score for leg pain, or ODI at the final follow-up among the three groups (p > 0.05).

CONCLUSIONS

Although radiological results were different among the three groups of patients, postoperative clinical outcomes were significantly improved after each type of surgery. The percutaneous biportal or uniportal endoscopic approach offers the advantage of reduced immediate postoperative pain. A percutaneous uniportal or biportal endoscopic lumbar approach may be effective for the treatment of lumbar central stenosis and an alternative to conventional microsurgical decompression.

Long-term clinical outcomes after bilateral laminotomy or total laminectomy for lumbar spinal stenosis: a single-institution experience

OBJECTIVE

Lumbar spinal stenosis (LSS) is the most common spinal disease in the geriatric population, and is characterized by a compression of the lumbosacral neural roots from a narrowing of the lumbar spinal canal. LSS can result in symptomatic compression of the neural elements, requiring surgical treatment if conservative management fails. Different surgical techniques with or without fusion are currently treatment options. The purpose of this study was to provide a description of the long-term clinical outcomes of patients who underwent bilateral laminotomy compared with total laminectomy for LSS.

METHODS

The authors retrospectively reviewed all the patients treated surgically by the senior author for LSS with total laminectomy and bilateral laminotomy with a minimum of 10 years of follow-up. Patients were divided into 2 treatment groups (total laminectomy, group 1; and bilateral laminotomy, group 2) according to the type of surgical decompression. Clinical outcomes measures included the visual analog scale (VAS), the 36-Item Short-Form Health Survey (SF-36) scores, and the Oswestry Disability Index (ODI). In addition, surgical parameters, reoperation rate, and complications were evaluated in both groups.

RESULTS

Two hundred fourteen patients met the inclusion and exclusion criteria (105 and 109 patients in groups 1 and 2, respectively). The mean age at surgery was 69.5 years (range 58–77 years). Comparing pre- and postoperative values, both groups showed improvement in ODI and SF-36 scores; at final follow-up, a slightly better improvement was noted in the laminotomy group (mean ODI value 22.8, mean SF-36 value 70.2), considering the worse preoperative scores in this group (mean ODI value 70, mean SF-36 value 38.4) with respect to the laminectomy group (mean ODI 68.7 vs mean SF-36 value 36.3), but there were no statistically significant differences between the 2 groups. Significantly, in group 2 there was a lower incidence of reoperations (15.2% vs 3.7%, p = 0.0075).

CONCLUSIONS

Bilateral laminotomy allows adequate and safe decompression of the spinal canal in patients with LSS; this technique ensures a significant improvement in patients’ symptoms, disability, and quality of life. Clinical outcomes are similar in both groups, but a lower incidence of complications and iatrogenic instability has been shown in the long term in the bilateral laminotomy group.

Selective versus multi-segmental decompression and fusion for multi-segment lumbar spinal stenosis with single-segment degenerative spondylolisthesis

Background

Lumbar spinal stenosis, often accompanied by degenerative spondylolisthesis, is one of the most common conditions in the elderly. Decompression and fusion is a well-accepted treatment for single-segment lumbar spinal stenosis with degenerative spondylolisthesis; however, the treatment for multi-segment lumbar spinal stenosis with single-segment degenerative spondylolisthesis (MLSS) remains controversial. The objective of this study is to compare the effectiveness of selective decompression and fusion to multi-segmental decompression and fusion for MLSS.

Methods

A total of 42 patients suffering from MLSS who underwent surgery between June 2012 and January 2015 were included in this analysis. Of the 42 patients with minimum 3-year follow-up, 22 underwent selective decompression and fusion, and 20 patients underwent multi-segmental decompression and fusion. Age, gender, symptom duration, operative time, blood loss, the number of decompressed segment and fused segment, and complication were compared between the two groups. The visual analog scale (VAS), Oswestry Disability Index (ODI) and Short Form 36 (SF-36) were used to assess efficacy.

Results

Operative time, blood loss, and the number of fused segment in multi-segmental decompression and fusion group were greater than those in selective decompression and fusion group (P < 0.01). The VAS, ODI, and SF-36 scores at 1-year follow-up and 3-year follow-up were significantly improved compared with those preoperatively in both groups (P < 0.01) but were not significantly different between the two groups at each time point (P > 0.05). There was no iatrogenic spinal instability in the decompressed segments in selective decompression and fusion group, while three patients developed postoperative instability at the adjacent segments above the fused segments in multi-segmental decompression and fusion group at 3-year follow-up.

Conclusions

Selective decompression and fusion is a safe and effective method for the treatment of MLSS, with the advantages of shorter operative time, less blood loss, and more preservation of spinal motion segments when compared with multi-segmental decompression and fusion.

Endoscopic and Microscopic Segmental Decompression via Translaminar Crossover Spinal Approach in Elderly Patients

OBJECTIVE

For effective minimally invasive lumbar decompression, we changed the routine of segmental decompression. Using a high-speed drill or an ultrasound knife, we created a working channel, starting at the base of the spinous process of the upper vertebra slightly above the disc level, to target and decompress the contralateral recess, and termed it the translaminar crossover decompression (TCD). We evaluated the feasibility and compared the outcomes of a navigation-guided endoscopic translaminar crossover approach for segmental decompression (eTCD) in elderly patients with microscopic decompression using the same approach (mTCD).

METHODS

A total of 740 elderly patients were enrolled in a prospective cohort study. Of the 740 patients, 297, who had undergone mTCD, and 253, who had undergone eTCD, completed a 1-year follow-up visit. In addition to the surgical data, numerical rating scales (NRSs) for back and leg pain, the Core Outcome Measures Index and Oswestry Disability Index were recorded preoperatively and 3, 6, and 12 months after surgery. The MacNab criteria were supplemented by qualitative assessment of the patients' postoperative pain-free walking distance.

RESULTS

A comparison of the preoperative and postoperative clinical scores showed significant improvement after TCD in both cohorts (P < 0.01): Oswestry Disability Index, from 50.3% ± 12.6% to 15.5% ± 7.43%; NRS (back), from 6.9 ± 1.9 to 2.5 ± 1.3; NRS (leg), from 8.0 ± 0.85 to 1.6 ± 0.33; Core Outcome Measures Index (back), from 7.8 ± 2.0 to 2.7 ± 1.5. No statistically significant differences were found in the outcomes between the 2 cohorts.

CONCLUSIONS

TCD inherently eliminated central stenosis and facilitated decompression of both recesses via mutual undercutting, with preservation of facet joint integrity.

Comparison of clinical outcomes following minimally invasive or lumbar endoscopic unilateral laminotomy for bilateral decompression

OBJECTIVE

Minimally invasive lumbar unilateral tubular laminotomy for bilateral decompression has gradually gained acceptance as a less destabilizing but efficacious and safe alternative to traditional open decompression techniques. The authors have further advanced the principles of minimally invasive surgery (MIS) by utilizing working-channel endoscope-based techniques. Full-endoscopic technique allows for high-resolution off-axis visualization of neural structures within the lateral recess, thereby minimizing the need for facet joint resection. The relative efficacy and safety of MIS and full-endoscopic techniques have not been directly compared.

METHODS

A retrospective analysis of 95 consecutive patients undergoing either MIS (n = 45) or endoscopic (n = 50) unilateral laminotomies for bilateral decompression in cases of lumbar spinal stenosis was performed. Patient demographics, operative details, clinical outcomes, and complications were reviewed.

RESULTS

The patient cohort consisted of 41 female and 54 male patients whose average age was 62 years. Half of the patients had single-level, one-third had 2-level, and the remaining patients had 3- or 4-level procedures. The surgical time for endoscopic technique was significantly longer per level compared to MIS (161.8 ± 6.8 minutes vs 99.3 ± 4.6 minutes; p < 0.001). Hospital stay for MIS patients was on average 2.4 ± 0.5 days compared to 0.7 ± 0.1 days for endoscopic patients (p = 0.001). At the 1-year follow-up, endoscopic patients had a significantly lower visual analog scale score for leg pain than MIS patients (1.3 ± 0.3 vs 3.0 ± 0.5; p < 0.01). Moreover, the back pain disability index score was significantly lower in the endoscopic cohort than in the MIS cohort (20.7 ± 3.4 vs 35.9 ± 4.1; p < 0.01). Two patients in the MIS group (epidural hematoma) and one patient in the endoscopic group (disc herniation) required a return to the operating room acutely after surgery (< 14 days).

CONCLUSIONS

Lumbar endoscopic unilateral laminotomy for bilateral decompression is a safe and effective surgical procedure with favorable complication profile and patient outcomes.

Minimally invasive decompression in patients with degenerative spondylolisthesis associated with lumbar spinal stenosis. Report of a surgical series and review of the literature

We reported the results of minimally invasive spinal decompression (MISD) in patients with degenerative spondylolisthesis (DS) associated with lumbar spinal stenosis (LSS) and performed a literature review in order to evaluate the clinical and radiological outcomes, the complications and reoperation rate of MISD procedures in these patients. Data of 28 patients submitted to MISD for DS associated to LSS were reviewed. We evaluated the Visual Analogue Scale (VAS) both for low back pain (LBP) and legs pain, the Oswestry Disability Index (ODI) and the degree of the slippage. A PubMed search of the English literature was conducted. Only papers with more than 10 patients and reporting explicitly data of patients with DS were included in the analysis. We found a statistically significant improvement of LBP, legs pain and ODI in our series. The degree of slippage was stable at follow-up (FU) with no need of reoperation. No major complications occurred. In our literature review, we were able to analyze the differences in ODI in 156 patients and the differences in Japanese Orthopedic Association (JOA) score in 218 patients. We observed a statistically significant improvement of ODI and JOA score at FU compared to pre-operative. The percentage of slippage, evaluated in 283 patients, was unchanged at FU compared to pre-operative. The overall complication rate was 1.6%. The overall reoperation rate was 4.5%. MISD procedures are safe and effective in patients with DS associated to LSS and are associated to low morbidity and significant improvement of disability without progression of slippage.

Pedicle distraction increases intervertebral and spinal canal area in a cadaver and bone model

INTRODUCTION

Lumbar spinal stenosis is degenerative narrowing of the spinal canal and/or intervertebral foramen causing compression of the spinal cord and nerve roots. Traditional decompression techniques can often cause significant trauma and vertebral instability. This paper evaluates a method of increasing pedicle length to decompress the spinal and intervertebral foramen, which could be done minimally invasive.

METHODS

Three Sawbone (Sawbones Europe, Sweden) and 1 cadaveric lumbar spine underwent bilateral pedicle distraction at L4. A pedicle channel was drilled between the superior articular process and transverse process into the vertebral body. The pedicles underwent osteotomy at the midpoint. Screws were inserted bilaterally and fixated distraction of 0 mm, 2 mm, 4 mm and 6 mm. CT images were taken at each level of distraction. Foramen area was measured in the sagittal plane at L3/4. Spinal canal area was measured at L4 in the axial images. The cadaver was used to evaluate safety of osteotomy and soft tissue interactions preventing distraction. Statistical analysis was by student paired t-test and Pearson rank test.

RESULTS

Increasing distraction led to greater Spinal canal area. From 4.27 cm² to 5.72 cm² (p = 0.002) with 6 mm distraction. A Maximal increase of 34.1%. Vertebral foramen area also increased with increasing pedicle distraction. From 2.43 cm² to 3.22 cm² (p = 0.022) with 6 mm distraction. A maximal increase of 32.3%. The cadaver spinal canal increased in area by 21.7%. The vertebral foramen increased in area by 36.2% (left) and 22.6% (right).

DISCUSSION

For each increase in pedicle distraction the area of the spinal and vertebral foramen increases. Pedicle distraction could potentially be used to alleviate spinal stenosis and root impingement. A potential osteotomy plane could be at the midpoint of the pedicle with minimal risk to nerve roots and soft tissue restrictions to prevent distraction.

Navigated minimally invasive unilateral laminotomy with crossover for intraoperative prediction of outcome in degenerative lumbar stenosis

BACKGROUND

Different surgical techniques have been described for treatment of degenerative lumbar stenosis (DLS). Only postoperative measures have been identified as predictors of efficacy of decompression. The objective of this study is to assess the role of navigated unilateral laminotomy with crossover to achieve and predict a satisfying decompression and outcome in DLS.

MATERIALS AND METHODS

We enrolled patients with DLS who underwent navigation-assisted unilateral laminotomy with crossover. The extent of decompression was evaluated during surgery using neuronavigation. The outcome was assessed through the Oswestry disability index (ODI) and visual analog scale (VAS) for leg pain. Outcome correlation with the extent of the intraoperative bone decompression was analyzed. Finally, the outcome, surgical time, and in-hospital length-of-stay were compared with a control group treated through standard unilateral laminotomy.

RESULTS

Twenty-five patients were treated using the navigated technique (Group A), 25 using the standard unilateral laminotomy (Group B). In Group A, a cut-off value ≥0.9 cm for bone decompression revealed to be an intraoperative predictor of good outcome, both regarding the ODI and VAS scores (P = 0.0005; P = 0.002). As compared with Group B, patients operated using the navigated technique showed similar operative times, in-hospital length-of-stay, ODI scores, but improved VAS scores for leg pain (P = 0.04).

CONCLUSIONS

The intraoperative navigated evaluation of the bone decompression could predict the outcome allowing satisfactory results in unilateral laminotomy for DLS. The navigated technique also could lead to an improved decompression of lateral recesses resulting in better control of leg pain as compared to standard unilateral laminotomy.

Effectiveness of a Decision-Making Protocol for the Surgical Treatment of Lumbar Stenosis with Grade 1 Degenerative Spondylolisthesis

BACKGROUND

Addition of fusion to decompression for stenosis with grade 1 degenerative spondylolisthesis is a controversial topic, and the question remains if fusion provides any benefit to the patient that warrants the increased health care utilization and perioperative morbidity. There is no consensus on indications for use of fusion over decompression alone.

METHODS

Patients received fusion or decompression according to a decision-making protocol based on their pattern of complaints, location of the compression, and facet angles and effusion as proven predictors of postoperative instability. Propensity score matching of patients was done for baseline data.

RESULTS

The study comprised 102 patients in 2 equally sized groups. No intergroup differences in numeric rating scale and Oswestry Disability Index were detected at any follow-up point (all P > 0.05). Duration of surgery, length of stay, estimated blood loss, and radiation doses were higher in the fusion group (all P < 0.001). Cumulative reoperation rate was similar with 6% for fusion and 8% for decompression (P > 0.05), as was the complication rate (8% vs. 6%, P > 0.05). Postoperative iatrogenic progression of spondylolisthesis requiring fusion surgery was seen in only 2% in the decompression group.

CONCLUSIONS

Use of a decision-making protocol led to a low rate of iatrogenically increased spondylolisthesis after decompression, while retaining outcomes. These data suggest that a decision-making protocol based on clinical history, location of nerve root compression, and proven radiologic predictors of postoperative instability assigns patients to fusion or decompression in a safe and effective manner.

Emerging Techniques in Degenerative Thoracolumbar Surgery

There continue to be incremental advances in thoracolumbar spine surgery techniques in attempts to achieve more predictable outcomes, minimize risk of complications, speed recovery, and minimize the costs of these interventions. This paper reviews recent literature with regard to emerging techniques of interest in the surgical treatment of lumbar spinal stenosis, fusion fixation and graft material, degenerative lumbar spondylolisthesis, and thoracolumbar deformity and sacroiliac joint degeneration. There continue to be advances in minimal access options in these areas, although robust outcome data are heterogeneous in its support. The evidence in support of sacroiliac fusion appears to be growing more robust in the properly selected patient.

Minimally invasive techniques for lumbar decompressions and fusions

PURPOSE OF REVIEW

The purpose of this study is to summarize the recent literature investigating the use of minimally invasive (MIS) techniques in the treatment of lumbar degenerative stenosis, spondylolisthesis, and scoliosis.

RECENT FINDINGS

MIS lumbar decompression and fusion techniques for degenerative pathology are associated with reduced operative morbidity, shortened length of hospital stay, and reduced postoperative pain and narcotics utilization. Recent studies with long-term clinical follow-up have demonstrated equivalence in clinical outcomes between open and MIS surgical procedures. Radiographically, MIS procedures provide adequate postoperative correction of coronal alignment. Correction of sagittal alignment, however, is more variable based on current reports. MIS techniques are both safe and effective in the treatment of lumbar degenerative pathologies. While some studies have reported on long-term outcomes and costs associated with MIS procedures, more investigation into these topics is still necessary. Additionally, further work is required to analyze the training requirements and learning curves of MIS procedures to better promote adoption amongst surgeons.

Long-term Clinical and Radiological Outcomes after Central Decompressive Laminoplasty for Lumbar Spinal Stenosis

OBJECTIVE

There are many technical modifications of decompressive lumbar laminectomy. The purpose of this study was to report long-term clinical and radiological outcomes of central decompressive laminoplasty (CDL), the corresponding author's own modification of lumbar laminectomy for lumbar spinal stenosis (LSS).

METHODS

Among 100 patients who underwent CDL by a single surgeon between December 2010 and March 2014, 68 patients were included in this study. Mean follow-up time was 37.7 months. Clinical and radiological data were gathered prospectively and reviewed retrospectively. Clinical outcome was measured by using visual analog scale (VAS) for back/buttock and leg, and the Oswestry Disability Index (ODI). Radiological outcome was measured by neutral slippage percentage, dynamic slippage percentage, and dynamic intervertebral angel on sagittal X-ray. Outcomes after CDL were assessed by changes of clinical and radiological parameters from the baseline. Mixed effect model with random patients' effect as used to test for differences in the repeated measured clinical and radiological data.

RESULTS

The patients had no serious complications with an uneventful recovery during the early postoperative period. In the early postoperative period, VAS scores for back/buttock and leg improved significantly and were kept with time (p<0.001). ODI also improved significantly during the postoperative follow-up period (p<0.001). The radiologic parameters were well maintained and showed no progression of instability. During the follow-up, a case of herniated disc at same level recurrence was noted after lifting trauma, and 2 adjacent foraminal stenosis needed additional surgery.

CONCLUSION

CDL provides long-term pain relief and functional restoration without progression of radiological instability.

Study-protocol for a randomized controlled trial comparing clinical and radiological results after three different posterior decompression techniques for lumbar spinal stenosis: the Spinal Stenosis Trial (SST) (part of the NORDSTEN Study)

Background

There are several posterior decompression techniques for lumbar spinal stenosis (LSS). There is a trend towards performing less invasive surgical procedures, but no multicentre randomized controlled trials have evaluated the relative efficacy of these techniques at short and long-term.

Method/design

A multicentre randomized controlled trial [the Spinal Stenosis Trial (SST) (part of the NORDSTEN study)] including 465 patients aged 18–80 years with neurogenic claudication or radiating pain and MRI findings indicating lumbar spinal stenosis without spondylolisthesis is performed to compare three posterior decompression techniques: unilateral laminotomy with crossover, bilateral laminotomy and spinous process osteotomy. The primary outcome is change in Oswestry Disability Index (ODI 2 years postoperatively). Secondary outcomes are change in EQ-5D, Zurich Claudication Questionnaire, and Numeric Rating Scale for leg-pain and back-pain. Also recorded were Global Perceived Effect score, complications, length of hospital stay, reoperation rate 2 years postoperatively, difference in recurrence of symptoms or postoperative instability, and MRI change in the dural sac area. Further, a 5 and 10 years follow-up is planned with the same outcome measures.

Discussion

Newer and less invasive techniques are increasingly favoured in surgery for LSS. This trial will compare the clinical and radiological results of three different techniques, and may contribute to better clinical decision making in the surgical treatment of LSS.

Trial registration

ClinicalTrials.gov reference: NCT02007083 (November 22, 2013).

Lumbar degenerative spondylolisthesis epidemiology: A systematic review with a focus on gender-specific and age-specific prevalence

The epidemiology of lumbar degenerative spondylolisthesis (DS) remains controversial. We performed a systematic review with the aim of gaining a better understanding of the prevalence of DS in the general population. The results showed that the prevalence of DS is very gender- and age-specific. Few women and men develop DS before they are 50 years old. After 50 years of age, both women and men begin to develop DS, with women having a faster rate of development than men. For elderly Chinese (≥ 65 years, mean age: 72.5 years), large population-based studies MsOS (Hong Kong, females: n = 2000) and MrOS (Hong Kong, males: n = 2000) showed DS prevalence was 25.0% in women and 19.1% in men. The female:male (F:M) prevalence ratio was 1.3:1. The published data for MsOS (USA) and MrOS (USA) studies seem to show that elderly Caucasian Americans have a higher DS prevalence, being approximately 60-70% higher than elderly Chinese; however, the F:M prevalence ratio was similar to the elderly Chinese population. Patient data showed that female patients more often received surgical treatment than male and preliminary data showed the ratio of female to male patients receiving surgical treatment did not differ between Northeast Asians (Chinese, Japanese, and Korean), Europeans, and American Caucasians, being around 2:1 in the elderly population. The existing data also suggest that menopause may be a contributing factor for the accelerated development of DS in postmenopausal women. The translational potential of this article: A better understanding of epidemiology of lumbar degenerative spondylolisthesis can support patient consultation and treatment planning.