A systematic review of clinical outcomes in surgical treatment of adult isthmic spondylolisthesis

Clinical and Radiologic Comparisons Between Oblique Lumbar Interbody Fusion Combined with Percutaneous Pedicle Screw Fixation and Transforaminal Lumbar Interbody Fusion for Adult Isthmic Spondylolisthesis: A 2-year Follow-Up Study

BACKGROUND

Adult isthmic spondylolisthesis (AIS) results in the anterior translation of the vertebral body with neural encroachment. Although oblique lumbar interbody fusion (OLIF) is minimally invasive technique that uses a retroperitoneal plane to achieve indirect decompression compared to transforaminal lumbar interbody fusion (TLIF), research on OLIF for AIS remains limited. Therefore, we aimed to compare the clinical and radiologic outcomes of these 2 surgical techniques for AIS.

METHODS

We analyzed the details of 62 patients with AIS who were treated with either OLIF (n = 26) or TLIF (n = 36) between 2019 and 2022, with a minimum 2-year follow-up. The 2 surgical techniques were compared in terms of perioperative surgical, radiologic, and clinical outcomes. The correlation between the severity of foraminal stenosis and clinical outcomes was evaluated.

RESULTS

The OLIF group experienced significantly less blood loss, shorter operative times, and shorter hospital stay than the TLIF group. Radiologic assessments showed no significant preoperative differences in disc height or slippage ratios, but postoperative slippage correction was significantly greater in the OLIF group than in the TLIF group (13.5 ± 8.0 vs. 5.0 ± 8.9; P < 0.001). The clinical outcome improvement ratios did not differ significantly between the 2 groups. The correlation between preoperative severity of foraminal stenosis and clinical outcomes in the OLIF group was not significant.

CONCLUSIONS

OLIF is more advantageous than TLIF in terms of blood loss, operative time, hospital stay, and anterolisthesis correction. In addition, good clinical outcomes were obtained with indirect decompression alone, regardless of the severity of foraminal stenosis. Therefore, OLIF is a good surgical option for the treatment of AIS.

Patient-reported outcome of lumbar decompression with instrumented fusion for low-grade spondylolisthesis: influence of pathology and baseline symptoms

INTRODUCTION

Low-grade isthmic and degenerative spondylolisthesis (DS) of the lumbar spine are distinct pathologies but both can be treated with lumbar decompression with fusion. In a very large cohort, we compared patient-reported outcome in relation to the pathology and chief complaint at baseline.

METHODS

This was a retrospective analysis using the EUROSPINE Spine Tango Registry. We included 582 patients (age 60 ± 15 years; 65% female), divided into four groups based on two variables: type of spondylolisthesis and chief pain complaint (leg pain (LP) versus back pain). Patients completed the COMI preoperatively and up to 5 years follow-up (FU), and rated global treatment outcome (GTO). Regression models were used to predict COMI-scores at FU. Pain scores and satisfaction ratings were analysed.

RESULTS

All patients experienced pronounced reductions in COMI scores. Relative to the other groups, the DS-LP group showed between 5% and 11% greater COMI score reduction (p < 0.01 up to 2 years' FU). This group also performed best with respect to pain outcomes and satisfaction. Long-term GTO was 93% at the 5 year FU, compared with between 82% and 86% in the other groups.

CONCLUSION

Regardless of the type of spondylolisthesis, all groups experienced an improvement in COMI score after surgery. Patients with DS and LP as their chief complaint appear to benefit more than other patients. These results are the first to show that the type of the spondylolisthesis and its chief complaint have an impact on surgical outcome. They will be informative for the consent process prior to surgery and can be used to build predictive models for individual outcome.

Comparison of ALIF and PLIF in Isthmic Lumbosacral Spondylolisthesis. A Multicenter Surveillance Study of 602 cases from the German Spine Registry (DWG Register)

BACKGROUND

 Isthmic spondylolisthesis most commonly occurs in the lumbosacral junction and can cause backpain and radicular pain as well as stiffness with progressive immobilization, with a negative impact on an individual's ability to work and quality of life. Multiple operative treatments are currently available. This study aims to compare complications, demography, and clinical features between anterior lumbar interbody fusion (ALIF) and posterior lumber body fusion (PLIF) in the operative treatment in isthmic spondylolisthesis.

METHODS

 An analysis of data from the German spine registry (Deutsche Wirbelsäulengesellschaft [DWG]-Register) of patients who underwent operative treatment (PLIF and ALIF) for isthmic spondylolisthesis in the sacrolumbar junction in 170 departments between January 2017 and May 2021 was performed. Age, gender, American Society of Anesthesiologists (ASA) score, surgical approach, smoker/nonsmoker, as well as severeness of the spondylolisthesis according to the Meyerding classification were evaluated.

RESULTS

 In total, 602 patients undergoing fusion in L5/S1 were identified in the registry, n = 570 PLIF (group 1) and n = 32 ALIF (group 2). A significant difference in the ASA score between the two groups was noted; group 1 had more patients suffering a more debilitating disease in comparison to group 2. There was no significant difference in gender, grade of spondylolisthesis, age, or smoking status. Significant differences were found in operative and postoperative variables and complications (fusion material, dura injury).

CONCLUSION

 No difference was found between the two procedures in terms of symptomatic benefit of patients who underwent either ALIF or PLIF. According to the DWG Register, PLIF was the preferred method to treat isthmic spondylolisthesis in the sacrolumbar junction in Germany. To compare these two spine fusion techniques, further studies with an adequate sample size and follow-up period are required.

Impact of body mass index on assisted reproductive technology outcomes in patients with polycystic ovary syndrome: a meta-analysis

The effect of obesity on pregnancy outcomes of patients with polycystic ovary syndrome (PCOS) undergoing assisted reproductive technology (ART) remains unclear. As such, a meta-analysis of recent studies was conducted to probe the effect of being overweight or obese on ART pregnancy outcomes in patients with PCOS. PubMed, Embase, MEDLINE, Scopus and Web of Science were searched from inception to 22 July 2023 without language restrictions. The main indicators were: live birth rate, clinical pregnancy rate, spontaneous abortion rate and multiple pregnancy rate. Ten studies were analysed, with a combined sample size of 247,845. Among patients with PCOS undergoing ART who were overweight or obese, the live birth rate, clinical pregnancy rate, implantation rate and number of retrieved oocytes were lower than in normal-weight patients with PCOS, and the spontaneous abortion rate was higher than in normal-weight patients with PCOS. Obese patients with PCOS undergoing ART had a lower multiple pregnancy rate and a lower number of mature oocytes compared with normal-weight patients with PCOS. The data showed that, among patients with PCOS, being overweight or obese has a negative effect on ART pregnancy outcomes. This meta-analysis may inform guidelines for pregnancy with ART, and encourage overweight or obese patients with PCOS to lose weight.

Combined Transforaminal Lumbar Interbody Fusion and Smiley Face Rod Technique Using Dual-Headed Pedicle Screws for L4 Isthmic Spondylolisthesis and L5 Spondylolysis

Spondylolysis with pseudarthrosis may be treated surgically by repairing the spondylolysis using the smiley face rod (SFR) technique. The SFR technique can avoid adjacent segmental disease caused by transforaminal lumbar interbody fusion (TLIF), which is one of the main surgical techniques to treat isthmic lumbar spondylolisthesis. A 59-year-old woman had been playing softball since she was 12 years old and was a member of a prefectural representative team. She sought treatment because of numbness in her left lower limb and difficulty playing softball. Despite conservative treatment for a year, her symptoms did not improve. Physical examination revealed decreased patellar tendon reflexes and numbness and pain from the front of the thigh to the lower leg without muscle weakness. Imaging showed L4 isthmic spondylolisthesis with Meyerding classification grade 2 anterior slip and L5 spondylolysis with pseudarthrosis. We diagnosed L4 radiculopathy caused by L4/5 foraminal stenosis and L4 isthmic spondylolisthesis with L5 spondylolysis. She underwent surgery combining the TLIF of L4/5 and the SFR technique of L5 using dual-headed pedicle screws that can fix two types of rods with L5 pedicle screws. Three months after surgery, fusion between L4/5 and fusion of the L5 pars cleft were confirmed. She resumed sports, and one year postoperatively, she was able to participate in softball games. Two years postoperatively, she could bat, run, and play defense without adjacent segmental disease. Two-segment TLIF increases adjacent segmental disease more than single-segment TLIF. Because the L5 spondylolysis had not slipped, we chose the SFR technique to preserve mobility at L5/S1. The dual-headed pedicle screw fastens two-type rods at the head of the pedicle screw, making it a suitable design for this procedure.

Return to Play Criteria After Adult Lumbar Spinal Fractures: A Review of Current Literature and Expert Recommendations

PURPOSE OF REVIEW

Understanding the management of lumbar spinal fractures and return to play (RTP) criteria is an essential component of care for adult athletes. Appropriate management of lumbar spinal fractures must balance minimizing time away from physical activity while also minimizing risk of reinjury. The purpose of this review is to summarize current recommendations on lumbar spinal fracture management and RTP guidelines and to provide expert opinion on areas of discrepancy in the field.

RECENT FINDINGS

There is a paucity of high-level evidence on the management and return to play criteria for adult lumbar spine fractures in athletes. Much of the data and recommendations are based on expert opinion and studies in pediatric or osteoporotic patients, which may not be applicable to adult athletes. These data presented here may be used to aid patient-physician conversations and provide guidance on expectations for patients, coaches, and athletic trainers. In general, we recommend that patients be free of lumbar pain, neurologically intact, and have full strength and motion of the lumbar spine and lower extremities before returning to play. Adequate protective equipment is recommended to be worn at all times during practice and play.

Clinical efficacy of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in the treatment of II° lumbar isthmic spondylolisthesis: A retrospective cohort study

Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is not suitable for high-grade isthmic spondylolisthesis, whether MIS-TLIF can treat II° lumbar isthmic spondylolisthesis (IS) is still controversial. This retrospective cohort study compared the clinical efficacy of MIS-TLIF and open transforaminal lumbar interbody fusion (OPEN-TLIF) in the treatment of II° lumbar IS. From January 2017 to January 2023, 101 patients with II° lumbar IS were diagnosed in our hospital and underwent surgical treatment, of which 53 received MIS-TLIF surgery and 48 received OPEN-TLIF surgery. The operation time, blood loss and surgical complications were compared between the 2 groups. The pain, function, reduction rate and fusion rate of the patients were evaluated during follow-up. The amount of intraoperative blood loss, postoperative drainage, and postoperative hospital stay in the MIS-TLIF group were significantly lower than those in the OPEN-TLIF group were (P < .01). In the MIS-TLIF group, there were 1 case of dural sac injury and 3 cases of lower limb paralysis. The complication rate of MIS-TLIF was lower than the OPEN-TLIF group (P = .032). In the visual analog scale score of low back pain, the MIS-TLIF group was lower than the OPEN-TLIF group after operation and at the last follow-up. There were no significant differences in postoperative leg pain score, slippage rate, and fusion rate between the 2 groups. Compared with OPEN-TLIF, MIS-TLIF has the advantages of better low back pain relief, less trauma, less bleeding and faster recovery, and is worthy of clinical promotion.

Surgical management of isthmic spondylolisthesis: A comparative study of postoperative outcomes between ALIF and TLIF

INTRODUCTION

Circumferential fusion by the anterior (ALIF) or transforaminal (TLIF) approach combined with posterior instrumentation is currently used for the surgical treatment of low-grade isthmic spondylolisthesis. But few studies have compared the clinical and radiological outcomes of various interbody fusion techniques. The objective of this study was to compare the clinical and radiological results at 2 years postoperative of two fusion techniques-TLIF versus ALIF plus posterior instrumentation-for low-grade isthmic spondylolisthesis in adults.

MATERIALS AND METHODS

This was an observational multicenter study done at nine French healthcare facilities specialized in spine surgery. The inclusion criteria were minimum age of 18 years, grade 1-3 isthmic spondylolisthesis, ALIF+posterior fixation (ALIF+PS) or TLIF, minimum follow-up of 2 years. Clinical and radiological evaluations were done preoperatively and at 2 years of follow-up. A lumbar CT scan was done at 1 year postoperative to evaluate fusion.

RESULTS

The cohort consisted of 89 patients (50 women, 39 men) with a mean age of 47.7±12.3 (18-79) years. The patients in the ALIF groups (n=71) had a significantly longer hospital stay than those in the TLIF group (n=18): 5.7 days versus 4.6 days (p=.04). However, their medical leave from work was significantly shorter: 31.0 weeks versus 40.7 (p=.003). Lumbar pain VAS diminished faster in the ALIF groups, with a significantly larger drop than the TLIF group in the first 3 months postoperative. Only the increase in lumbar disc lordosis was larger in the ALIF group: 11.7°±12.0° versus 6.0°±11.7° (p=.036). There was a significant correlation between the increase in global lordosis and reduction in lumbar VAS at 2 years postoperative (ρ=-0.3295; p=.021).

CONCLUSION

ALIF+PS provides a faster relief of postoperative low back pain than TLIF but there are no significant clinical differences between techniques at 2 years of follow-up. Despite better restoration of disc lordosis in the ALIF+PS group, there was no difference in the restoration of global lordosis.

LEVEL OF EVIDENCE

III; multicenter comparative study.

A Novel Technique for Pars Defect Direct Repair with a Modified Smiley Face Rod for Spondylolysis and Isthmic Spondylolisthesis

Introduction

Lumbar spondylolysis is a common fatigue fracture of the pars interarticularis of the lamina of the lumbar spine in adolescent athletes presenting with pars clefts. Some pseudarthrotic lumbar spondylolysis causes low back pain or radiculopathy. This study presents a case of pseudarthrotic lumbar spondylolysis that was successfully treated using a modified smiley face rod technique.

Technical Note

We developed a modified smiley face rod technique, which places pedicle screws in the lateral edge of the pedicle to preserve the erector spinae muscles and inserts a U-shaped rod between the spinous processes to preserve the supraspinous ligament. When a U-shaped rod penetrates the interspinous ligament subcutaneously, the resection of the supraspinous ligaments can be avoided. When the screw head is positioned more anterolaterally, a compression force is applied perpendicular to the surface of the pars cleft by rod clamping. This intrasegmental fusion technique preserves the mobile segment and simultaneously repairs the pars cleft. It is less invasive and more appropriate than interbody fusion for young athletes to avoid the possibility of future adjacent segment disorders.

Conclusions

This is a minimally invasive procedure that can easily achieve bone fusion and should be introduced for patients who are suffering from the symptoms of pseudarthrotic lumbar spondylolysis.

Response to Preoperative Steroid Injections Predicts Surgical Outcomes in Patients Undergoing Fusion for Isthmic Spondylolisthesis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The decision to pursue operative intervention for patients with isthmic spondylolisthesis is complex. Although steroid injections are a well-accepted therapeutic modality that may delay or obviate surgery, little is known regarding their ability to predict surgical outcomes.

SUMMARY OF BACKGROUND DATA

Here, we examine whether improvement after preoperative steroid injections can accurately predict clinical outcomes after surgery.

METHODS

A retrospective cohort analysis was performed on adult patients undergoing primary posterolateral lumbar fusion for isthmic spondylolisthesis between 2013 and 2021. Data were stratified into a control (no preoperative injection) group and an injection group (received a preoperative diagnostic and therapeutic injection). We collected demographic data, peri-injection visual analog pain scores (VAS) pain scores, PROMIS pain interference and physical function scores, Oswestry Disability Index, and VAS pain (back and leg). Student t test was utilized to compare baseline group characteristics. Linear regression was performed comparing changes in peri-injection VAS pain scores and postoperative measures.

RESULTS

Seventy-three patients did not receive a preoperative injection and were included in the control group. Fifty-nine patients were included in the injection group. Of patients who received an injection, 73% had >50% relief of their preinjection VAS pain score. Linear regression revealed a positive interaction between the injection efficacy and postoperative pain relief as measured by VAS leg scores ( P <0.05). There was also an association between injection efficacy and back pain relief, though this did not achieve statistical significance ( P =0.068). No association was found between injection efficacy and improvement in Oswestry Disability Index or PROMIS measures.

CONCLUSIONS

Steroid injections are often utilized in the nonoperative therapeutic management of patients with lumbar spine disease. Here, we demonstrate the diagnostic value of steroid injections in predicting postoperative leg pain relief in patients undergoing posterolateral fusion for isthmic spondylolisthesis.

Transforaminal Lumbar Interbody Fusion Versus Posterolateral Fusion Alone in the Treatment of Grade 1 Degenerative Spondylolisthesis

BACKGROUND

Transforaminal lumbar interbody fusion (TLIF) and posterolateral fusion (PLF) alone are two operations performed to treat degenerative lumbar spondylolisthesis. To date, it is unclear which operation leads to better outcomes.

OBJECTIVE

To compare TLIF vs PLF alone regarding long-term reoperation rates, complications, and patient-reported outcome measures (PROMs) in patients with degenerative grade 1 spondylolisthesis.

METHODS

A retrospective cohort study using prospectively collected data between October 2010 and May 2021 was undertaken. Inclusion criteria were patients aged 18 years or older with grade 1 degenerative spondylolisthesis undergoing elective, single-level, open posterior lumbar decompression and instrumented fusion with ≥1-year follow-up. The primary exposure was presence of TLIF vs PLF without interbody fusion. The primary outcome was reoperation. Secondary outcomes included complications, readmission, discharge disposition, return to work, and PROMs at 3 and 12 months postoperatively, including Numeric Rating Scale-Back/Leg and Oswestry Disability Index. Minimum clinically important difference of PROMs was set at 30% improvement from baseline.

RESULTS

Of 546 patients, 373 (68.3%) underwent TLIF and 173 underwent (31.7%) PLF. Median follow-up was 6.1 years (IQR = 3.6-9.0), with 339 (62.1%) >5-year follow-up. Multivariable logistic regression showed that patients undergoing TLIF had a lower odds of reoperation compared with PLF alone (odds ratio = 0.23, 95% CI = 0.54-0.99, P = .048). Among patients with >5-year follow-up, the same trend was seen (odds ratio = 0.15, 95% CI = 0.03-0.95, P = .045). No differences were observed in 90-day complications ( P = .487) and readmission rates ( P = .230) or minimum clinically important difference PROMs.

CONCLUSION

In a retrospective cohort study from a prospectively maintained registry, patients with grade 1 degenerative spondylolisthesis undergoing TLIF had significantly lower long-term reoperation rates than those undergoing PLF.

Abnormal L5-S1 Facet Joint Orientation as a Harbinger of Degenerative Spondylolisthesis: A Case Report

Degenerative spondylolisthesis is a common cause of low back pain and resultant disability in the adult population. The causes of degenerative spondylolisthesis are not entirely understood, though a combination of anatomic and lifestyle factors likely contributes to the development of this pathology. Here, we report a case of a 38-year-old female presenting with low back pain and right lower extremity radiculopathy, found to have degenerative L5-S1 spondylolisthesis, which we postulate developed in part due to the sagittal orientation of her L5-S1 facet joints bilaterally.

Enhancing endoscopic foraminal decompression in adult isthmic spondylolisthesis: the potential influence of lateral recess isthmic spur and our case series of an innovative craniocaudal interlaminar approach via unilateral biportal endoscopic spinal surgery

BACKGROUND

The NASS guideline cannot recommend any of the surgical treatment options toward adult isthmic spondylolisthesis (AIS) since 2014. After the introduction of endoscopic decompression, instead of treating the spondylolysis itself, treatment can specifically target the refractory radicular pain developed during the degeneration progress without devastating the peripheral soft tissue. However, we noticed that endoscopic transforaminal decompression seems to be less effective in AIS compared to other types of degenerative spondylolisthesis. Thus, we came up with a novel craniocaudal interlaminar approach, utilizing the proximal adjacent interlaminar space to perform bilateral decompression and observed the pathoanatomy of pars defect directly and tried to identify the cause of decompression failure.

METHODS

From January 2022 to June 2022, 13 patients with AIS underwent endoscopic decompression via the endoscopic craniocaudal interlaminar approach and were followed up for at least 6 months. Visual Analogue Scale, Oswestry Disability Index and MacNab scores were recorded to monitor patients' clinical recovery. All endoscopic procedures were recorded and reviewed to illustrate the pathoanatomy.

RESULTS

Four patients required minor revision via the same technique. One of them required it due to incomplete isthmic spur resection, two due to neglected disc protrusion, and the other due to root subpedicular kinking in higher grade anterolisthesis. All patients' clinical condition improved significantly subsequently. After reviewing the endoscopic video, we have observed that the hook-like, ragged spur originating from the isthmic defect extends beyond the region around the foramen. Instead, it extends proximally into the adjacent lateral recess, resulting in impingement along the fracture edge above the index foramen and, in some cases, even in the extraforaminal area.

CONCLUSIONS

The broad spanning isthmic spur extending to the proximal adjacent lateral recess might be the reason why the transforaminal approach yielded less satisfactory results due to the incomplete decompression result from approach related restriction. Our study demonstrated an optimistic outcome by applying decompression from the upper level. Therefore, we propose that the craniocaudal interlaminar approach might be a better route for decompression in adult isthmic spondylolisthesis.

Effect of COVID-19 vaccination on the outcome of in vitro fertilization: A systematic review and meta-analysis

Background

Universal COVID-19 vaccination programs are now recommended in several countries and represent the most effective preventive measure against COVID-19. However, some reports suggest that vaccination may cause infertility or have adverse effects on pregnancy. Conflicting reports have led to vaccine hesitancy in women planning pregnancy.

Purpose

To determine whether vaccination against COVID-19 affects in vitro fertilization (IVF) outcomes, we conducted a meta-analysis.

Method

A systematic search was conducted using PubMed, Embase, MEDLINE, and Web of Science databases for all published literature on COVID-19 vaccines and outcomes of IVF. International Prospective Register of Systematic Reviews registration was completed on September 13, 2022 (CRD42022359771).

Results

We analyzed 20 studies totaling 18,877 individual cases undergoing IVF. COVID-19 vaccination had significant effect on clinical and ongoing pregnancy rate (risk ratio (RR): 0.97; 95% confidence interval (CI): 0.94–0.99; RR: 0.93; 95% CI: 0.87–0.99). These outcomes did not differ between vaccinated and unvaccinated individuals: biochemical pregnancy rate (RR: 0.95; 95% CI: 0.88–1.03), implantation rate (RR: 1.02; 95%CI: 0.97–1.07; P = 0.41), the number of oocytes (mean difference (MD): 0.12; 95% CI: −0.65–0.88) and MII/mature oocytes recovered (MD: 0.27; 95% CI: −0.36–0.90), blastocysts rate (MD: 0.01; 95% CI: −0.04, 0.06), and fertilization rate (MD: 1.08; 95% CI: −0.57, 2.73).

Conclusion

Our findings suggest that vaccination against COVID-19 does not adversely affect the biochemical pregnancy rates; number of oocytes and MII/mature oocytes obtained; implantation, blastocysts; and fertilization rates in women undergoing IVF treatment. Subgroup analysis showed that the mRNA vaccine had no statistical significance on all indexes (clinical, biochemical, or ongoing pregnancy rates; implantation, blastocysts, or fertilization rates; and the number of oocytes and MII/mature oocytes). The findings of this meta-analysis are anticipated to increase the willingness of women planning IVF treatment to receive COVID-19 vaccination and provide evidence-based medical guidance for the development and implementation of guidelines.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022359771.

Fusion and clinical outcomes of lumbar interbody fusion for low-grade isthmic spondylolisthesis

INTRODUCTION

Low-grade isthmic spondylolisthesis (ISPL) is generally treated by circumferential fusion with interbody graft, although there is no consensus on technique.

HYPOTHESIS

The various interbody fusion strategies provide satisfactory fusion rates and clinical results.

METHODS

A multicenter retrospective study analyzed lumbar interbody fusion for low-grade ISPL performed between March 2016 and March 2019. Techniques comprised: circumferential fusion on a posterior or a transforaminal approach (PLIF, TLIF: n=57), combined anterior (ALIF)+posterolateral fusion (ALIF+PLF: n=60), and ALIF+percutaneous posterior fixation (ALIF+PPF: n=55). Function was assessed on a lumbar and a radicular visual analog scale (AVS-L, VAS-R), Oswestry Disability Index (ODI) and Short Form 12 (SF12).

RESULTS

Among the 129 patients, 85.3% showed fusion (Lenke 1 or 2), with no significant differences between the ALIF-PLF or ALIF-PPF groups and the PLIF or TLIF groups (p=0.3). Likewise, there was no difference in fusion rates between the ALIF-PPF and ALIF-PLF subgroups (p=0.28). VAS-L (p<0.001) and VAS-R (p<0.0001), ODI (p<0.001) and SF12 physical (PCS) (p<0.01) and mental component sores (MCS) (p<0.001) all showed significant improvement at 12months. Combined approaches provided greater clinical efficacy than TLIF or PLIF for lumbar (p<0.0001) and radicular pain (p<0.05), ODI (p<0.0001) and SF12 PCS (p<0.01). At 12months, there was no clinical difference between the ALIF-PPF and ALIF-PLF subgroups. However, patents with interbody non-union (Lenke 3 or 4) had lower SF12 PCS scores (p<0.004) and VAS-L ratings (p<0.001) than Lenke 1-2 patients.

CONCLUSION

Low-grade ISPL treated by circumferential arthrodesis and interbody graft showed 85.3% consolidation at 2years, with equivalent outcomes between anterior and posterior techniques. Successful fusion was associated with better clinical results.

LEVEL OF EVIDENCE

IV.

Trends of Different Surgical Approaches in Patients With Single-Level Lumbar Isthmic Spondylolisthesis: A National Registry Analysis

BACKGROUND

A variety of surgical approaches (anterior vs. posterior vs. anterior and posterior) are available for Isthmic Spondylolisthesis (IS). The aim of our study was to analyze the pattern and 30-day outcomes in patients undergoing different surgical approaches for single-level IS.

MATERIALS AND METHODS

National Surgical Quality Improvement Program (NSQIP) database was queried using the ICD-9/10 and CPT 4^th edition, from 2012 to 2020. We included patients 18-65 years of age who underwent spine fusions for IS. Outcomes were a length of stay (LOS), discharge disposition, 30-day complications, hospital readmission, and complication rates.

RESULTS

Of 1036 patients who underwent spine fusions for IS, 838 patients (80.8%) underwent posterior only, 115 patients (11.1%) underwent anterior-only fusions and the rest (8%) underwent combined anterior and posterior procedures. 60% of patients in the posterior-only cohort had at least one comorbidity compared to 54% of patients in anterior only and 55% of patients in the combined cohort. No statistically significant differences in terms of LOS (3 days each) and discharge to home (96% vs. 93% vs. 94%) were noted among the anterior-only, posterior-only and combined cohorts, p> 0.05. In terms of 30-day complication rates, combined procedures had slightly higher rates (13%) compared to anterior (10%) or posterior-only (9%) procedures.

CONCLUSION

Posterior-only fusions were performed in 80% of patients with IS. No differences in terms of LOS, discharge disposition to home, 30-day complications, hospital readmission and reoperation rates were noted across the cohorts.

In Single-Level, Open, Posterior Lumbar Fusion, Does Transforaminal Lumbar Interbody Fusion or Posterolateral Fusion Lead to Better Outcomes?

BACKGROUND

Two common approaches for open, one-level, posterior lumbar fusions include transforaminal lumbar interbody fusion (TLIF) and posterolateral fusion (PLF) alone without an interbody.

OBJECTIVE

To compare TLIF vs PLF alone in (1) discharge disposition, (2) return to work (RTW), and (3) patient-reported outcomes (PROs).

METHODS

A single-center, retrospective cohort study was undertaken between October 2010 and May 2021, all with a 1-year follow-up and excluding patients with isthmic spondylolisthesis. Minimum clinically important difference for each PRO was used, which included Numeric Rating Scale (NRS) and Oswestry Disability Index (ODI). Logistic/linear regression controlled for age, body mass index, disc height, flexion-extension movement, amount of movement on flexion-extension, and spondylolisthesis grade.

RESULTS

Of 850 patients undergoing open, 1-level, posterior lumbar fusion, 591 (69.5%) underwent a TLIF and 259 (30.5%) underwent a PLF alone. Patients undergoing TLIF were younger (59.0 ± 11.3 vs 63.3 ± 12.6, P < .001), had higher body mass index (31.3 ± 6.6 vs 30.2 ± 12.6, P = .019), and more often had private insurance (50.3% vs 39.0%, P < .001). Regarding discharge disposition, no significance was found in multivariate regression (odds ratio = 2.07, 95% CI = 0.39-10.82, P = .385) with similar RTW between TLIF and PLF alone (80.8% vs 80.4%, P = .645) (odds ratio = 1.15, 95% CI = 0.19-6.81, P = .873). Regarding PROs, patients undergoing a TLIF had higher preoperative (6.7 ± 2.3 vs 6.4 ± 2.5, P = .046) and 3-month NRS-back pain (3.4 ± 2.6 vs 2.9 ± 2.5, P = .036), with similar 12-month NRS-back pain. Regarding NRS-leg pain, no differences were observed preoperatively ( P = .532) and at 3 months ( P = .808). No other significant differences were observed in ODI.

CONCLUSION

TLIF patients had slightly higher NRS-back pain at baseline and 3 months, but similar NRS-leg pain, despite the added risk of placing an interbody. No differences were seen in discharge disposition, RTW, and 12-month pain scores and ODI.

Application of Oblique Lateral Interbody Fusion Combined with Bridge-Locking Cage in Adjacent Segment Disease After Lumbar Fusion

OBJECTIVE

Adjacent segment disease (ASD) is considered any abnormal process that develops in the mobile segment next to spinal fusion, accompanied by related symptoms. To evaluate the efficacy and complications of oblique lateral interbody fusion (OLIF) combined with bridge-locking fusion on ASD after lumbar fusion.

METHODS

A total of 35 ASD patients who required re-operation after lumbar fusion in our hospital from March 2014 to March 2020 were retrospectively analyzed, among which 13 cases (seven males and six females; 62.3 ± 11.3 years old) received the treatment of OLIF + bridge-locking cage internal fixation (OLIF group), and 22 cases (14 males and eight females; 52.3 ± 17.8 years old) received the treatment of transforaminal lumbar interbody fusion (TLIF) + pedicle screw fixation (TLIF group). The comparison of the operation time, intraoperative blood loss, postoperative drainage volume, and length of hospital stay between the two groups of patients was performed using the t-test. The comparison of Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) at different time points before and after the operation was performed using analysis of variance for repeated measurement data. The fusion rate and postoperative complications of the two groups of patients were also evaluated.

RESULTS

The operation time of patients in the OLIF group (55.4 ± 12.4 min) was significantly shorter than that of patients in the TLIF group (94.3 ± 22.9 min) (P < 0.05), the length of stay of patients in the OLIF group (7.4 ± 2.3 day) was significantly shorter than that of patients in the TLIF group (12.4 ± 3.2 day) (P < 0.05); the intraoperative blood loss (62.2 ± 30.1 mL) and postoperative drainage (47.3 ± 22.4 mL) of patients in the OLIF group were significantly less than those of patients in the TLIF group with intraoperative blood loss (363.4 ± 120.2 mL) and postoperative drainage (285.5 ± 57.8 mL) (all Ps < 0.05). Besides, the VAS and ODI scores of the two groups of patients were improved 3 months after the operation and at the last follow-up (all Ps < 0.05). Three patients in the OLIF group developed complications such as hip flexion weakness and fusion cage sink, with an incidence of 23.1%. Three patients in the TLIF group developed complications including wound infection and intraoperative nerve injury, with an incidence of 22.7%.

CONCLUSION

The combination of OLIF and bridge-locking cage may be a safe and effective therapy for ASD patients after lumbar fusion operation.

Outcomes Following Direct Versus Indirect Decompression Techniques for Lumbar Spondylolisthesis: A Propensity-Matched Analysis

STUDY DESIGN

Retrospective review.

OBJECTIVE

The aim was to compare outcomes at 3 and 12 months for patients with lumbar spondylolisthesis treated with direct decompression (DD) versus indirect decompression (ID) techniques.

SUMMARY OF BACKGROUND DATA

Debate persists regarding the optimal surgical strategy to treat lumbar spondylolisthesis. Novel techniques relying on ID have shown superior radiographic outcomes compared to DD, however, doubt remains regarding their effectiveness in achieving adequate decompression. Currently, there is a paucity of data comparing the clinical efficacy of DD to ID.

METHODS

The Quality Outcomes Database (QOD), a national, multicenter prospective spine registry, was queried for patients who underwent DD and ID between April 2013 and January 2019. Propensity scores for each treatment were estimated using logistic regression dependent on baseline covariates potentially associated with outcomes. The propensity scores were used to exclude nonsimilar patients. Multivariable regression analysis was performed with the treatment and covariate as independent variables and outcomes as dependent variables.

RESULTS

A total of 4163 patients were included in the DD group and 86 in the ID group. The ID group had significantly lower odds of having a longer hospital stay and for achieving 30% improvement in back and leg pain at 3 months. These trends were not statistically significant at 12 months. There were no differences in ED5D scores or Oswestry disability index 30% improvement scores at 3 or 12 months. ID patient had a significantly higher rate of undergoing a repeat operation at 3 months (4.9% vs. 1.5%, P =0.015).

CONCLUSION

Our study suggests that both DD and ID for the treatment of lumbar spondylolisthesis result in similar clinical outcomes, with the exception that those treated with ID experienced a lower reduction in back and leg pain at 3 months and a higher 3-month reoperation rate. This data can provide surgeons with additional information when counseling patients on the pros and cons of ID versus DD surgery.

Surgical Reduction and Direct Repair Using Pedicle Screw-Rod-Hook Fixation in Adult Patients with Low-Grade Isthmic Spondylolisthesis

Background

Although direct pars repair using a pedicle screw-rod-hook system has achieved satisfactory results in patients with spondylolysis, its application in adults with low-grade isthmic spondylolisthesis is rarely reported.

Objective

To assess the surgical effect of reduction and direct repair surgery with a pedicle screw-rod-hook system combined with autogenous bone grafts in adult patients with low-grade isthmic spondylolisthesis.

Methods

Sixty-four adult patients with low-grade isthmic spondylolisthesis underwent reduction and direct repair using a pedicle screw-rod-hook system in our department from September 2009 to April 2018. The clinical efficacy was evaluated by clinical and radiological assessments.

Results

The average follow-up was 52.15 ± 9.96 months. The visual analog scale (VAS) scores (VAS-lumbar and VAS-leg) and Oswestry Disability Index (ODI) at the final follow-up (FFU) were significantly lower than the preoperative levels (P < 0.05). The modified Prolo score was “excellent” for 60 patients (93.75%) and “good” for 4 patients (6.25%). The slip distance and slipping percentage showed significant decreases postoperatively and FFU compared to preoperatively (P < 0.05). There were no significant differences in the disc height, slip angle, and range of motion of the surgical intervertebral space or upper intervertebral space between preoperation and FFU (P < 0.05). Successful bony fusion had a 96.86% success rate.

Conclusion

Reduction of slip and direct repair using pedicle screw-rod-hook fixation combined with autogenous iliac bone grafting in adult patients with low-grade isthmic spondylolisthesis is a safe and effective technique.

Isthmic spondylolisthesis in adults… A review of the current literature

Isthmic spondylolisthesis can be defined as the anterior translation of a vertebral body relative to the one subjacent to it and secondary to an abnormality of the pars interarticularis. Isthmic spondylolisthesis is usually asymptomatic and discovered as an incidental radiographic finding. However, it can be symptomatic due to its biomechanical effects on the adjacent neural structures and patients may present with low back and/or radicular leg pain. Standing plain radiographs can be obtained to confirm the presence or assess the degree of isthmic spondylolisthesis. Computed tomography (CT) clearly shows the pars defect and provides a better assessment of the pathology. Magnetic resonance imaging (MRI) is indicated in patients with neurologic manifestations and can be used to assess the degree of foraminal or central stenosis. Conservative management including oral anti-inflammatory medication, physical therapy, and/or transforaminal epidural corticosteroid injections can be utilized initially. Surgery can be considered in the setting of persistent symptoms unrelieved with conservative management or significant neurologic compromise. Several surgical methods and techniques are available in the management of isthmic spondylolisthesis. There has been a significant national increase in the use of interbody fusion posteriorly for the management of isthmic spondylolisthesis. Reports have suggested that interbody fusion can be a cost-effective technique in selected patients with isthmic spondylolisthesis. Future studies are encouraged to further characterize the specific indications of various surgical modalities in patients with isthmic spondylolisthesis.

Better Functional Recovery After Single-Level Compared With Two-Level Posterolateral Lumbar Fusion

Background

Multiple studies describe the outcomes of patients undergoing single-level and multilevel posterolateral lumbar fusion (PLF). However, a comparison of outcomes between single-level and two-level PLF is lacking. The aim of this prospective cohort study was to compare outcomes between single-level and two-level instrumented PLF.

Methods

A total of 42 patients were enrolled at nine US centers between October 2015 and June 2017. Data included radiologic outcomes, visual analog scale (VAS) Back and Leg Pain, disability per the Oswestry Disability Index (ODI), and health-related quality of life (QoL) per 36-Item Short Form Survey version 2.0 (SF-36v2) at six weeks and three, six, 12, and 24 months.

Results

Twelve-month and 24-month follow-ups were completed by 38 (90.5%) and 32 (76.2%) subjects, respectively. The average age was 67 years, and 54.8% were female. Twenty-six received single-level PLF, and 16 received two-level PLF. In the single-level group, there was one reoperation, two postoperative infections, and one dural tear. In the two-level group, there was one postoperative infection. The surgeon computed tomography (CT)-based evaluation of fusion rate was 67.6% (25/37) at 12-month follow-up and 94.1% (32/34) at 24-month follow-up. The third-party evaluation of fusion rate was 52.8% (19/36) at six months, 81.1% (30/37) at 12 months, and 86.5% (32/37) at 24 months. There was a tendency toward a higher fusion rate in single-level compared with two-level PLF. The ODI, SF-36v2 Mental Component Score (MCS), and VAS Back Pain and Leg Pain outcomes improved by the first follow-up visit in both the single-level and two-level groups. Improvement in the ODI was 5.86 (95% confidence interval (CI): 0.03-11.69) points greater in the single-level group compared with the two-level group.

Conclusions

Compared with the two-level PLF subjects, single-level PLF subjects had better functional outcomes and reported higher satisfaction with the outcome of surgery but showed similar fusion, pain, and generic health-related quality of life outcomes. Both single-level and two-level PLF subjects demonstrated high fusion rates in association with improvements in pain, functional, and quality of life outcomes, as well as high satisfaction levels.

Isthmic spondylolisthesis treated with circumferential arthrodesis (ALIF and posterior fixation): correction, fusion and indirect decompression

There is no consensus regarding the choice of the surgical technique for isthmic spondylolisthesis treatment, although they all aim to a common goal, achieving fusion at the index level while restoring an appropriate lordosis and remove potential radicular compression. Analyze outcome of circumferential arthrodesis (CA) with ALIF (Anterior Lumbar Interbody Fusion) and pedicle screw fixation for the treatment of all-grade isthmic spondylolisthesis, with indirect neurological decompression. Retrospective study of isthmic spondylolisthesis treated with CA, with one-year follow-up. Clinical scores were collected at one year: VAS-L, VAS-R and ODI. Pelvic parameters, L4-S1 lordosis and at index and adjacent levels, and lumbo-sacral angle (LSA) were measured pre- and post-operatively and at last follow-up. Foraminal surface and diameters were measured pre- operatively and at follow-up on CT-Scan. Level of evidence: IV. 87 patients were included. Mean VAS-L was 2.3, mean VAS-R was 1, and mean ODI was 13.8%. 10% of the patients presented a high-grade spondylolisthesis and 50% a grade II. Mean lordosis at index level shifted from 6° to 18°, L4-S1 lordosis increased from 37 to 45° and LSA shifted from 116 to 125° (p<0.001). The foraminal surface increased from 50mm 2 to 70mm 2 at last follow-up mostly through the supero-inferior diameter, shifting from 7.4mm to 9.5mm (p<0.001). In LSA<90° group, mean correction was 20° at index level, 13° at L4-S1 and 21° for LSA versus 11°, 8° and 8° respectively in LSA>90° group (p<0.001). Fusion rate was estimated at 96.5%. One infection, 5 sympathetic dysfunctions, one retrograde ejaculation, one iliac vein injury, one incisional hernia, one lateral femoral cutaneous nerve injury and two adjacent syndromes have been noted. CA is an efficient technique for the treatment of isthmic spondylolisthesis of all grades, with an acceptable rate of complications. It allows a restoration of the regional lordosis as well as a foraminal widening, avoiding additional decompression.

Flexion-extension standing radiographs underestimate instability in patients with single-level lumbar spondylolisthesis: comparing flexion-supine imaging may be more appropriate

BACKGROUND

Generally, most spine surgeons agree that increased segmental motion viewed on flexion-extension radiographs is a reliable predictor of instability; however, these views can be limited in several ways and may underestimate the instability at a given lumbar segment.

METHODS

Consecutively collected adult (≥18 years old) patients with symptomatic single-level lumbar spondylolisthesis were reviewed from a two-surgeon database from 2015 to 2019. Routine standing lumbar X-rays (neutral, flexion, extension) and supine lumbar MRI (sagittal T2-weighted imaging sequence) were performed. Patients were excluded if they had prior lumbar surgery, missing radiographic data, or if the time between X-rays and MRI was >6 months.

RESULTS

All 39 patients with symptomatic, single-level lumbar spondylolisthesis were identified. The mean age was 57.3±16.7 years and 66% were female. There was good intra- and inter-rater reliability agreement between measured values on the presence of instability. The slip percentage (SP) difference was significantly highest in the flexion-supine (FS) (5.7 mm, 12.3%) and neutral standing-supine (NS) (4.3 mm, 8.7%) groups, both of which were significantly higher compared with the flexion-extension (FE) group (1.8 mm, 4.5%, P<0.001). Ventral instability based on SP >8% was observed more frequently in FS (79.5%) and NS (52.6%) groups compared with FE group (16.7%, P<0.001). No statistically significant correlation was found between SP and disc angle for all radiographic views.

CONCLUSIONS

Comparing standing lateral and flexion X-rays with supine MRIs provides higher sensitivity to assess instability than standard flexion-extension radiographs. The FS and NS comparisons also show greater slip percentage differences at higher slip grades, but not at different lumbar levels. These changes are not dependent on age or gender.

A Qualitative Descriptive Study of Patient Experiences of Pain Before and After Spine Surgery

OBJECTIVE

The purpose of this study was to describe the preoperative and postoperative experiences of spine surgery from the patient's perspective to help inform behavioral health services provided before, during, and after hospitalization.

SETTING

Single urban academic tertiary care hospital.

METHODS

Semistructured interviews with 14 adults who underwent spine surgery. Interview transcriptions were analyzed using content analysis by three investigators to identify emergent themes.

RESULTS

Three broad domains with associated themes emerged from the analysis: 1) preoperative experience-preparation, worries, and expectations; 2) recovery process-activity and pain management strategies; and 3) postoperative support in recovery-family and social support.

CONCLUSIONS

The results of this qualitative descriptive study can be used to guide future perioperative behavioral health services for patients undergoing spinal surgery. Establishing realistic expectations of spine surgery and a comprehensive pain management plan are essential for adequate preoperative preparation. Furthermore, family involvement in the preoperative preparation for surgery is important for support of the patient during the recovery process.

Comparison of Clinical Outcomes Between Posterior Instrumented Fusion With and Without Interbody Fusion for Isthmic Spondylolisthesis

STUDY DESIGN

A multicenter ambispective study using the Canadian Spine Outcomes and Research Network to compare clinical outcomes in adult patients with isthmic spondylolisthesis who received surgery.

OBJECTIVE

The purpose of this study is to compare 1-year postoperative clinical outcomes between posterior instrumented fusion with and without interbody fusion in patients with isthmic spondylolisthesis.

SUMMARY OF BACKGROUND DATA

Despite the increased use of interbody fusion in patients with isthmic spondylolisthesis, clinical superiority has not been demonstrated. It remains unclear what the optimal surgical approach is for this population.

MATERIALS AND METHODS

The primary outcome was changed in leg pain at 1 year. Secondary outcomes were changed in Oswestry Disability Index, Short Form-12 Physical Component Score, and back pain at 1-year postoperative follow-up, estimated intraoperative blood loss, length of surgery, length of stay, number of transfusions, and adverse events. Descriptive statistics, Student t test, χ2 test, and stepwise multivariable regression were used for analysis.

RESULTS

In total, 300 patients were included in this study. Of the 300 patients, 252 received posterolateral instrumented fusion with interbody fusion and 48 received posterolateral instrumented fusion alone. There were no significant differences in primary and secondary clinical outcomes at 1-year postoperative follow-up between the 2 groups. There were no significant differences in estimated blood loss (441 vs. 356 mL), length of surgery (210 vs. 224 min), length of stay (4 vs. 4 d), rate of transfusions (5.6% vs. 8.3%), and number of adverse events (33% vs. 23%) between patients who received interbody fusion and patients who did not. The addition of interbody fusion was not a significant variable for primary and secondary clinical outcomes in the stepwise multivariable regression analysis.

CONCLUSIONS

There were no significant differences in clinical outcomes at 1 year or in the number of early complications between patients who received posterolateral fusion or posterior/transformational lumbar interbody fusion.

LEVEL OF EVIDENCE

Level III.

Critically Low Confidence in the Results Produced by Spine Surgery Systematic Reviews: An AMSTAR-2 Evaluation From 4 Spine Journals

STUDY DESIGN

A systematic cross-sectional survey of systematic reviews (SRs).

OBJECTIVE

To evaluate the methodological quality of spine surgery SRs published in 2018 using the updated AMSTAR 2 critical appraisal instrument.

METHODS

We identified the PubMed indexed journals devoted to spine surgery research in 2018. All SRs of spine surgical interventions from those journals were critically appraised for quality independently by 2 reviewers using the AMSTAR 2 instrument. We calculated the percentage of SRs achieving a positive response for each AMSTAR 2 domain item and assessed the levels of confidence in the results of each SR.

RESULTS

We identified 28 SRs from 4 journals that met our criteria for inclusion. Only 49.5% of the AMSTAR 2 domain items satisfied the AMSTAR 2 criteria. Critical domain items were satisfied less often (39.1%) compared with noncritical domain items (57.3%). Domain items most poorly reported include accounting for individual study risk of bias when interpreting results (14%), list and justification of excluded articles (18%), and an a priori establishment of methods prior to the review or registered protocol (18%). The overall confidence in the results was rated "low" in 2 SRs and "critically low" in 26.

CONCLUSIONS

The credibility of a SR and its value to clinicians and policy makers are dependent on its methodological quality. This appraisal found significant methodological limitations in several critical domains, such that the confidence in the findings of these reviews is "critically low."

High-Grade Spondylolisthesis in Adults: Current Concepts in Evaluation and Management

Background

Information regarding the treatment of high-grade spondylolisthesis (HGS) in adults has been previously described; however, previous descriptions of the evaluation and surgical management of HGS do not represent more recent and now established approaches. The purpose of the current review is to discuss current concepts in the evaluation and management of patients with HGS.

Methods

Literature review.

Results

HGS is diagnosed in up to 11.3% of adults with spondylolisthesis and typically presents as nonspecific lower back pain. Regarding evaluation, a thorough history and physical examination should be performed, which may help predict the presence of HGS. Diagnostic imaging, and specifically the use of spino-pelvic parameters, are now commonly implicated in guiding treatment course and prognosis. When surgical intervention is indicated, surgical approaches include in situ fusion variations, reduction and partial reduction with fusion, and vertebrectomy. Although the majority of studies suggest improvements with these approaches, the literature is limited by a low level of evidence with regards to the superiority of one technique when compared with others.

Conclusions

HGS is a unique cause of low back pain in adults that carries considerable morbidity, but rarely presents with neurologic symptoms. Although the definitions, classifications, and methods of diagnosis of this spinal deformity have been established and accepted, the ideal surgical management of this deformity remains highly debated. Fusion in situ techniques are often technically easier to perform and provide lower risk of neurologic complications, whereas reduction and fusion techniques offer greater restoration of global spino-pelvic balance. Preoperative spino-pelvic parameters may have utility in assisting in procedural selection; however, future, higher-quality and longer-term studies are warranted to determine the optimal surgical intervention among the widely available techniques currently used, and to better define the indications for these interventions.

Early outcomes and safety of outpatient (surgery center) vs inpatient based L5-S1 Anterior Lumbar Interbody Fusion

We seek to determine the outcomes of patients undergoing outpatient-based ALIF compared to a consecutive series of inpatient based ALIF performed during the same time period. 58 consecutive patients at a single outpatient surgery center underwent ALIF from June 2015 - August 2017 and 79 ALIF's were performed at 2 Inpatient hospitals. Electronic medical records were reviewed for perioperative and postoperative complications as well as secondary interventions. 62 patients met inclusion criteria (29 Outpatient, 33 Inpatient). The inpatient group was significantly older (44 vs 51; p = 0.01). There were 8 postoperative complications. There was no difference in secondary interventions; 28 patients underwent a total of 36 interventions postoperatively for pain. Secondary interventions were performed at an average of 128(outpatient) and 158(inpatient) days (p = 0.55). There was no difference in outcome scores between the inpatient/outpatient groups at any time. Patients receiving a secondary intervention showed no significant improvement in Back VAS scores but, demonstrated a strong trend (p = 0.06) towards leg pain improvement. Patients who did not undergo secondary intervention had significant improvement in both Back and Leg VAS scores at all time points (p < 0.05). Outpatient ALIF is a safe and reproducible procedure with complication rates consistent with or lower than published rates. Patients outcome scores were no different in the inpatient versus outpatient group. Interestingly, there was a high number of secondary interventions performed in both groups. Patients undergoing a secondary procedure did not get statistically significant improvement in Back VAS but, demonstrated a strong trend in Leg VAS patient reported outcome scores.

Quality and Safety Improvement in Spine Surgery

STUDY DESIGN

Review article.

OBJECTIVES

A narrative review of the literature on the current advances and limitations in quality and safety improvement initiatives in spine surgery.

METHODS

A comprehensive literature search was performed using Ovid MEDLINE focusing on 3 preidentified concepts: (1) quality and safety improvement, (2) reporting of outcomes and adverse events, and (3) prediction model and practice guidelines. The search was conducted under appropriate subject headings and using relevant text words. Articles were screened, and manuscripts relevant to this discussion were included in the narrative review.

RESULTS

Quality and safety improvement remains a major research focus attracting investigators from the global spine community. Multiple databases and registries have been developed for the purpose of generating data and monitoring the progress of quality and safety improvement initiatives. The development of various prediction models and clinical practice guidelines has helped shape the care of spine patients in the modern era. With the reported success of exemplary programs initiated by the Northwestern and Seattle Spine Team, other quality and safety improvement initiatives are anticipated to follow. However, despite these advancements, the reporting metrics for outcomes and adverse events remain heterogeneous in the literature.

CONCLUSION

Constant surveillance and continuous improvement of the quality and safety of spine treatments is imperative in modern health care. Although great advancement has been made, issues with reporting outcomes and adverse events persist, and improvement in this regard is certainly needed.

Biomechanical testing of different posterior fusion devices on lumbar spinal range of motion

BACKGROUND

Recent minimal-invasive posterior fusion devices are supposed to provide stability and obtain fusion in combination with interbody cages in the instrumented segment. The aim of the present study is to evaluate the primary stability of two minimal-invasive posterior prototypes compared to an established spinous process plate and standard pedicle screw instrumentation.

METHODS

Seven fresh frozen human cadaver lumbar spines (L2-L5) were tested in a spinal testing device with a moment of 7.5 Nm. Spinal stability was determined as mean range of motion (RoM) in the segment L3/L4 during extension-flexion, lateral bending and axial rotation. The RoM was measured during five conditions: 1. intact; 2. working prototype composed of an interspinous device and process plates; 3. an established spinous process fixation device 4. working prototype of facet fixation and 5. pedicle screw fixation.

FINDINGS

All devices caused a significant reduction of RoM during extension-flexion. The RoM during lateral bending was significantly reduced to 37% (of intact) by pedicle screws and 68% by facet fixation prototype. During axial rotation the RoM was significantly reduced to 52% by pedicle screws and to 86% by facet fixation prototype. The other devices had no significant influence on RoM during lateral bending and axial rotation.

INTERPRETATION

The facet fixation prototype provided less primary stability compared to pedicle screws, but had significant advantages over spinous process fixation techniques. The results encourage further testing of this implant as a minimal-invasive approach for posterior fixation.

[Vertebral three-dimensional motion characteristics of adjacent segments in patients with isthmic spondylolisthesis in vivo]

Objective

To observe vertebral three-dimensional motion characteristics of adjacent segments in patients with symptomatic L 4 isthmic spondylolisthesis (IS).

Methods

Fourteen symptomatic L 4 IS patients who underwent surgery treatment (trial group) and 15 asymptomatic volunteers without back pain and other lesions of spine (control group) were recruited. There was no significant difference in gender, age, body mass index, and bone mineral density between the two groups ( P>0.05). The three-dimensional reconstruction model of lumbar spine was acquired from the thin slice CT of the lumbar spine of the subjects by combining dual-X-ray fluoroscopy imaging system with spiral CT examination. The model was matched to the double oblique X-ray fluoroscopy images captured by dual-X-ray fluoroscopy imaging system at different active positions of the lumbar spine to reproduce the three-dimensional instantaneous of lumbar spondylolisthesis at different state of motion. The motion and relative displacement of adjacent segments (L 3, 4 and L 5, S 1) of spondylolisthesis were measured quantitatively by establishing a three-dimensional coordinate system at the geometric center of the vertebral body. The results were compared with those of the control group.

Results

When L 3, 4 in the control group were flexed flexion-extension, left-right twisting, and left-right bending, and when L 5, S 1 in the control group were flexed left-right twisting and left-right bending, the activity along the main axis of motion (main axis of motion) tended to increase compared with that along the corresponding coupled axis of motion (secondary axis of motion); however, this trend disappeared in the trial group, and the main and secondary movements were disordered. Because of the coronal orientation of the facet joints of L 5, S 1, the degree of motion along the main axis of motion decreased during flexion and extension, but this trend disappeared in the trial group. Compared with the control group, L 3, 4 in the trial group exhibited displacement instability in flexion-extension, left-right twisting, and left-right bending ( P<0.05); there was no significant difference in the relative displacement of L 5, S 1 intervertebral bodies along x, y, and z axes between the trial group and the control group in flexion-extension, left-right twisting, and left-right bending curvature ( P>0.05).

Conclusion

Patients with symptomatic L 4 IS have disorders of primary and secondary movement patterns in adjacent segments, while IS showed significantly displacement instability in L 3, 4 and significantly decreased motion in L 5, S 1.