Anterior Lumbar Interbody Fusion With and Without an "Access Surgeon": A Systematic Review and Meta-analysis

A novel surgical approach using the "lateral corridor" for minimally invasive oblique lumbar interbody fusion at L5-S1: a clinical series and technical note

PURPOSE

The minimally invasive oblique lumbar interbody fusion (MI-OLIF) L5-S1 was introduced to overcome the limitations of conventional fusion techniques, however, MI-OLIF is not possible using the standard method due to vascular structures in some cases. We aimed to introduce the "lateral corridor" and report the details of the surgical technique with a clinical case series.

METHODS

We utilized the lateral access route of the left common iliac vein and named it the "lateral corridor", to distinguish the technique from the standard technique (central corridor). The type and frequency of branch vessels that required additional manipulations were reviewed, and the frequency of intraoperative vascular injury was investigated.

RESULTS

Among the 107 patients who underwent MI-OLIF L5-S1, 26 patients (24.3%) who received the "lateral corridor" technique were included. Branch vessel ligation was required in 42.3% of the patients. The types of branch vessels that required ligation were seven cases (26.9%) of the iliolumbar vein (ILV) and six cases (23.1%) of ascending lumbar vein (ALV). The ILV and ALV were ligated in two cases. None of the patients developed intraoperative vascular injuries.

CONCLUSION

We introduced the "lateral corridor" as an alternative approach for MI-OLIF L5-S1, implemented it in 24.3% of the patient cohort, and reported favorable outcomes devoid of vascular complications. The "lateral corridor" necessitated ligation of the ILV or ALV in 42.3% of cases. The "lateral corridor" approach appears to be a promising surgical technique, offering feasibility even in instances where the vascular anatomy precludes the employment of the conventional approach.

Bilateral duplicated inferior vena cava associated with aberrant internal iliac and gonadal veins: A case-based narrative review

BACKGROUND

The left side anterior retroperitoneal approach is preferred for the management of lumbosacral spine disorders as there is reduced risk for vascular injury. The presence of multiple and uncommon venous variations on either side of the spine, like the bilateral duplicated inferior vena cava (DIVC), may complicate surgery in this region. The current study describes two rare cases of bilateral duplicated inferior vena cava associated with internal iliac and gonadal veins.

METHODS

The cases were identified during routine human dissections of the posterior abdominal wall of 89 (45 males, 44 females) individuals. The course, relations and morphometry of each duplicated inferior vena cava were examined and recorded.

RESULTS

Two (2.2%) of the 89 (1 male, 1 female) dissected individuals showed the presence of bilateral duplicated infrarenal segments of the inferior vena cava. In both cases, the pre-aortic trunk (vein) was the largest and the left inferior vena cava was the smallest. Both cases of bilateral DIVC presented with anomalous interiliac communicating veins, internal iliac veins, and drainage sites of the left gonadal veins.

CONCLUSIONS

The duplicated inferior vena cava may present with associated venous anomalies like those related to the gonadal and internal iliac veins. Knowledge of the duplicated inferior vena cava and its associated venous anomalies may be essential for accurately identifying and diagnosing vascular dysfunction and improving radiological interpretation across multiple surgical specialities.

Long-term comparison of anterior (ALIF) versus transforaminal (TLIF) lumbar interbody fusion: a propensity score-matched register-based study

PURPOSE

Anterior (ALIF) and transforaminal (TLIF) lumbar interbody fusion have shown similar clinical outcomes at short- and medium-term follow-ups. Possible advantages of ALIF in the long run could be better disc height and lumbar lordosis and reduced risk of adjacent segment disease. We aimed to study if ALIF could be associated with superior clinical outcomes than TLIF at long-term follow-up.

METHODS

We analysed 535 patients treated with ALIF or TLIF of the L5-S1 spinal segment between 2007 and 2017 who completed long-term follow-up in a national spine registry database (NORspine). We defined treatment success after surgery as at least 30% improvement in Oswestry Disability Index (ODI) at long-term follow-up. Patients treated with ALIF and TLIF and who responded at long term were balanced by propensity score matching. The proportions of successfully treated patients within each group were compared by numbers and percentages with corresponding relative risk.

RESULTS

The mean (95%CI) age of the total study population was 50 (49-51) years, and 264 (49%) were females. The mean (95%CI) preoperative ODI score was 40 (39-42), and 174 (33%) had previous spine surgery. Propensity score matching left 120 patients in each treatment group. At a median (95%CI) of 92 (88-97) months after surgery, we found no difference in proportions successfully treated patients with ALIF versus TLIF (68 (58%) versus 77 (65%), RR (95%CI) = 0.88 (0.72 to1.08); p = 0.237).

CONCLUSIONS

This propensity score-matched national spine register study of patients treated with ALIF versus TLIF of the lumbosacral junction found no differences in proportions of successfully treated patients at long-term follow-up.

LEVEL OF EVIDENCE I

Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.

Stand-alone ALIF versus TLIF in patients with low back pain - A propensity-matched cohort study with two-year follow-up

Introduction

Instrumented lumbar fusion by either the anterior or transforaminal approach has different advantages and disadvantages. Few studies have compared PatientReported Outcomes Measures (PROMs) between stand-alone anterior lumbar interbody fusion (SA-ALIF) and transforaminal lumbar interbody fusion (TLIF).

Research question

This is a register-based dual-center study on patients with severe disc degeneration (DD) and low back pain (LBP) undergoing single-level SA-ALIF or TLIF. Comparing PROMs, including disability, quality of life, back- and leg-pain and patient satisfaction two years after SA-ALIF or TLIF, respectively.

Material and methods

Data were collected preoperatively and at one and two-year follow-up. The primary outcome was Oswestry Disability Index (ODI). The secondary outcomes were patient satisfaction, walking ability, visual analog scale (VAS) scores for back and leg pain, and quality of life (QoL) measured by the European Quality of Life-5 Dimensions (EQ-5D) index score. To reduce baseline differences between groups, propensity-score matching was employed in a 1:1 fashion.

Results

92 patients were matched, 46 S A-ALIF and 46 TLIF. They were comparable preoperatively, with no significant difference in demographic data or PROMs (P > 0.10). Both groups obtained statistically significant improvement in the ODI, QoL and VAS-score (P < 0.01), but no significant difference was observed (P = 0.14). No statistically significant differences in EQ-5D index scores (P = 0.25), VAS score for leg pain (P = 0.88) and back pain (P = 0.37) at two years follow-up.

Conclusion

Significant improvements in ODI, VAS-scores for back and leg pain, and EQ-5D index score were registered after two-year follow-up with both SA-ALIF and TLIF. No significant differences in improvement.

Anterior Lumbar Interbody Fusion in Elderly Patients: Peri- and Postoperative Complications and Clinical Outcome

BACKGROUND

 Anterior lumbar interbody fusion (ALIF) is an effective surgical technique for treating various lumbar pathologies, but its use in elderly patients is controversial. Data concerning complications and effectiveness are sparse. We investigated peri- and postoperative complications, radiographic parameters, and clinical outcome in elderly patients.

METHODS

 Patients ≥65 years who underwent ALIF between January 2008 and August 2020 were included in the study. All surgeries were performed through a retroperitoneal approach. Clinical and surgical data as well as radiologic parameters were collected prospectively and analyzed retrospectively.

RESULTS

 A total of 39 patients were included; the mean age was 72.6 (±6.3) years (range: 65-90 years); and the mean American Society of Anesthesiologists (ASA) risk classification was 2.3 (±0.6). A laceration of the left common iliac vein was the only major complication recorded (2.6%). Minor complications occurred in 20.5% of patients. Fusion rate was 90.9%. Reoperation rate at the index level was 12.8 and 7.7% in adjacent segments. The multidimensional Core Outcome Measures Index (COMI) improved from 7.4 (±1.4) to 3.9 (±2.7) after 1 year and to 3.3 (±2.6) after 2 years. Oswestry disability index (ODI) improved from 41.2 (±13.7) to 20.9 (±14.9) after 1 year and to 21.5 (±18.8) after 2 years. Improvements of at least the minimal clinically important change score of 2.2 and 12.9 points in the ODI and COMI after 2 years were noted in 75 and 56.3% of the patients, respectively.

CONCLUSION

 With careful patient selection, ALIF is safe and effective in elderly patients.

Endoscopic anterior to psoas lumbar interbody fusion: indications, techniques, and clinical outcomes

PURPOSE

The retrospective study aimed to report the surgical technique and clinic-radiological outcomes of endoscopic anterior to psoas interbody lumbar fusion through the retroperitoneal approach with direct and indirect decompression.

METHODS

We retrospectively analyzed the results of clinical parameters of patients who underwent endoscopic anterior to psoas interbody lumbar fusion between June 2013 and June 2022. Clinical outcomes were evaluated by the visual analog scale (VAS) and Oswestry Disability Index (ODI) scores. The radiological outcomes were measured and statistically compared in disc height index (DHI), whole lumbar lordosis (WLL), pelvic Incidence (PI), pelvic tilt (PT), Segmental lordosis (SL), the sagittal vertical axis (SVA).

RESULTS

A total of 35 patients were selected for the procedure ranging in age from 51 to 84 years with 17.83 ± 8.85 months follow-up. The mean operation time in lateral position for one level was 162.96 ± 35.76 min (n = 24), and 207.73 ± 66.60 min for two-level fusion. The mean endoscopic time was 32.83 ± 17.71 min per level, with a total estimated blood loss of 230.57 ± 187.22 cc. The mean postoperative VAS back, leg pain score and ODI improved significantly compared to the preoperative values; Radiological data showed significant change in WLL, SL, DHI, PI, PT, and SS; however, there is no significant difference in SVA postoperatively. Subgroup analysis for the radiographic data showed 50 mm length cage has significantly improved for the DHI, SS and SVA compare to 40 mm length cage. The subgroup analysis results showed that hypertensive patients had significantly higher proportion in the incomplete fusion group compare to complete fusion group at one-year follow-up.

OUTCOMES

The endoscopic anterior to psoas interbody lumbar fusion achieves satisfactory indirect and direct decompression. This convergent technique presents an effective choice for treating lumbar instability associated with disc herniations and foraminal stenosis, thus complementing the indications for oblique lumbar interbody fusion.

Single position L5-S1 lateral ALIF with simultaneous robotic posterior fixation is safe and improves regional alignment and lordosis distribution index

PURPOSE

Minimally invasive single position lateral ALIF at L5-S1 with simultaneous robot-assisted posterior fixation has technical and anatomic considerations that need further description.

METHODS

This is a retrospective case series of single position lateral ALIF at L5-S1 with robotic assisted fixation. End points included radiographic parameters, lordosis distribution index (LDI), complications, pedicle screw accuracy, and inpatient metrics.

RESULTS

There were 17 patients with mean age of 60.5 years. Eight patients underwent interbody fusion at L5-S1, five patients at L4-S1, two patients at L3-S1, and one patient at L2-S1 in single lateral position. Operative times for 1-level and 2-level cases were 193 min and 278 min, respectively. Mean EBL was 71 cc. Mean improvements in L5-S1 segmental lordosis were 11.7 ± 4.0°, L1-S1 lordosis of 4.8 ± 6.4°, sagittal vertical axis of - 0.1 ± 1.7 cm°, pelvic tilt of - 3.1 ± 5.9°, and pelvic incidence lumbar-lordosis mismatch of - 4.6 ± 6.4°. Six patients corrected into a normal LDI (50-80%) and no patients became imbalanced over a mean follow-up period of 14.4 months. Of 100 screws placed in lateral position with robotic assistance, there were three total breaches (two lateral grade 3, one medial grade 2) for a screw accuracy of 97.0%. There were no neurologic, vascular, bowel, or ureteral injuries, and no implant failure or reoperation.

CONCLUSION

Single position lateral ALIF at L5-S1 with simultaneous robotic placement of pedicle screws by a second surgeon is a safe and effective technique that improves global alignment and lordosis distribution index.

Exploration of the Extraperitoneal Approach for Single-Level Anterior Lumbar Interbody Fusion: Imaging, Anatomical and Clinical Research

Background

To explore extraperitoneal approach as an optimal option for reducing peritoneal disruption at a single-level disc in anterior lumbar interbody fusion (ALIF).

Methods

First, abdominal axial CT images obtained from 111 patients were observed to evaluate the distribution of extraperitoneal fat at L2-S1 and measure the lateral distances between the midline and the lateral borders of the rectus and the extraperitoneal fat for each disc level. Second, eight embalmed corpses were dissected along the lateral border of the rectus to expose the peritoneum, which was then separated laterally and medially to evaluate the distribution of fat and peritoneum adhesion. Finally, a total of 58 patients were selected for ALIF. For L2-L4 discs and L4-S1, the pararectus approach and the paramedian approach were utilized, respectively.

Results

Extraperitoneal fat was observed behind the rectus at the L5-S1 and the lateral distance between the fat and midline and the lateral border of the rectus gradually decreased on both sides of L2-5. On the cranial side of the arcuate line, it was easier to separate the peritoneum outward along the lateral edge of the rectus. When bluntly dissected medially, the peritoneum was closely adhered to abdominal wall. No complications such as peritoneal damage, retroperitoneal hematoma and neurological complications occurred in 58 patients undergoing the aforementioned surgical methods.

Conclusions

For L4-S1, the paramedian approach is the optimal technique to expose the disc, whereas the pararectus approach is the feasible surgical method at L2-4.

A novel less invasive endoscopic-assisted procedure for complete reduction of low-and high-grade isthmic spondylolisthesis performed by anterior and posterior combined approach

PURPOSE

The optimal surgical management of low- and high-grade isthmic spondylolisthesis (LGS and HGS -IS) is debated as well as whether reduction is needed especially for high-grade spondylolisthesis. Both anterior and posterior techniques can be associated with mechanical disadvantages as hardware failure with loss of reduction and L5 injury. We purpose a novel endoscopic-assisted technique (Sled technique, ST) to achieve a complete reduction in two surgical steps: first anteriorly through a retroperitoneal approach to obtain the greatest part of correction and then posteriorly to complete reduction in the same operation.

METHODS

ST efficacy and complications rate were evaluated through a retrospective functional and radiological analysis.

RESULTS

Thirty-one patients, 12 male (38.7%) and 19 female (61.3%), average age: 45.4 years with single level IS underwent olisthesis reduction by ST. Twenty-three IS involved L5 (74.2%), 7 L4 (22.5%) and 1 L3 (3.3%). No intraoperative complications were recorded. One patient required repositioning of a pedicle screw. A significant improvement of functional and radiological parameters (L4-S1 and L5-S1 lordosis) outcomes was recorded (p < 0.001).

CONCLUSION

ST provides a complete reduction in the slippage in LGS and HGS. The huge anterior release as well as the partial reduction in the slippage by the endoscopic-assisted anterior procedure, because of the cage is acting as a "guide rail", facilitate the final posterior reduction, always complete in our series, minimizing mechanical stresses and neurological risks.

CLINICALTRIALS

gov Identifier: NCT03644407.

Case report: L5 tomita En bloc spondylectomy for oligometastatic liposarcoma with post adjuvant stereotactic ablative radiotherapy

Introduction

Tomita En-bloc spondylectomy of L5 is one of the most challenging techniques in radical oncological spine surgery. A 42-year-old female was referred with lower back pain and L5 radiculopathy with a background of right shoulder liposarcoma excision. CT-PET confirmed a solitary L5 oligometastasis. MRI showed thecal sac indentation hence wasn't suitable for Stereotactic Ablative Radiotherapy (SABR) alone. The seeding nature of sarcoma prevents the indication of separation surgery hence excisional surgery is considered for radical curative treatment. This case report demonstrates dual-staged modified TES including the utilisation of novel techniques to allow for maximum radical oncological control in the era of SABR and lesser invasive surgery.

Methods

First-stage: Carbonfibre pedicle screws planned from L2 to S2AI-Pelvis, aligned, to her patient-specific rods. Radiofrequency ablation of L5 pedicles prior to osteotomy was performed to prevent sarcoma cell seeding. Microscope-assisted thecal sac tumour separation and L5 nerve root dissection was performed. Novel surgical navigation of the ultrasonic bone-cutter assisted inferior L4 and superior S1 endplate osteotomies. Second-stage: Vascular-assisted retroperitoneal approach at L4–S1 was undertaken protecting the great vessels. Completion of osteotomies at L4 and S1 to En-bloc L5: (L4 inferior endplate, L4/5 disc, L5 body, L5/S1 disc and S1 superior endplate). Anterior reconstruction used an expandable PEEK cage obviating the need for a third posterior stage. Reinforced with a patient-specific carbon plate L4–S1 promontory.

Results

Patient rehabilitated well and was discharged after 42 days. Cyberknife of 30Gy in 5 fractions was delivered two months post-op. Despite left foot drop, she's walking independently 9 months post-op.

Conclusion

These are challenging cases require a truly multi-disciplinary team approach. We share this technique for a dual stage TES and metal-free construct with post adjuvant SABR to achieve maximum local control in spinal oligometastatic disease. This case promotes our modified TES technique in the era of SABR and separation surgery in carefully selected cases.

Adult Isthmic Spondylolisthesis: A Radiographic and Outcomes Analysis Comparing Circumferential Fusions Versus TLIF Procedures

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

The objective of this study was to compare radiographic and patient-reported outcome measures (PROMs) between circumferential fusions and transforaminal lumbar interbody fusion (TLIF) for adult isthmic spondylolisthesis (IS).

SUMMARY OF BACKGROUND DATA

Definitive management of adult IS typically requires decompression and fusion. Multiple fusion techniques have been described, but literature is sparse in identifying the optimal technique.

METHODS

Patients with IS undergoing single-level or 2-level circumferential fusion or TLIF with a minimum 1-year follow-up were included. Patient demographics, surgical characteristics, and PROMs were extracted from patients' electronic medical records. Descriptive statistics and multivariate regression analysis compared outcomes with significance set at P -value <0.05.

RESULTS

A total of 78 circumferential fusions (48 open decompression and fusions and 30 circumferential fusions utilizing posterior percutaneous instrumentation) and 50 TLIF procedures were included. Length of stay was significantly longer when comparing circumferential procedures (3.56±0.96 d) versus TLIFs (2.88±1.14 d) ( P =0.002). The circumferential fusion group resulted in greater postoperative improvement in segmental lordosis [anterior/posterior (A/P): 6.45, TLIF: -1.99, P <0.001], posterior disk height (A/P: 12.6 mm, TLIF: 8.9 mm, P <0.001), and ∆disk height (A/P: 7.7 mm, TLIF: 3.6 mm, P <0.001). Both groups significantly improved in all PROMs ( P <0.001). While the circumferential fusion group had a significantly higher rate of perioperative surgical complications (12.82% vs. 2.00%, P =0.049), there was no difference in the rate of 30-day readmissions ( P =0.520) or revision surgeries between techniques ( P =0.057).

CONCLUSIONS

Circumferential fusions are associated with improvements in radiographic outcomes compared with TLIFs, but this is at the expense of longer hospital length of stay and increased risk for perioperative complications. The surgical technique did not result in superior postoperative PROMs or differences in readmissions or revisions.

Management of lymphocele following anterior lumbar interbody fusion, case report and review of literature

While anterior lumbar interbody fusion (ALIF) is known as an established and safe procedure for treatment of degenerative disc disease, albeit rare, the development of postoperative intra-abdominal or retroperitoneal collection of lymph warrants timely diagnosis and management. This study presents the case of a 62-year-old male who underwent L4-L5 and L5-S1 ALIF and developed a persistent left-sided fluid collection, resulting in a symptomatic retroperitoneal lymphocele confirmed by computed tomography (CT). After percutaneous drainage by interventional radiology (IR), output remained high at 1 liter (L) per day, necessitating sclerotherapy with doxycycline and ethanol. In the absence of improvement, a lymphangiogram demonstrating a persistent lymph leak and glue embolization was performed. Due to refractory symptoms, retroperitoneal exploration with methylene blue dye was utilized for lymphatic mapping, and a lymphatic capillary leak in proximity to the left iliac artery was identified and successfully ligated with resolution of symptoms. With suspected fluid collections following ALIF, confirmation with CT or ultrasound (US) imaging followed by percutaneous drainage and testing of fluid is necessary. In mild cases, drainage alone or nonsurgical chemical sclerotherapy may suffice. In symptomatic refractory cases, localization of the site with lymphangiogram or US-guided injection of methylene blue dye allows for easier identification and definitive management with either transabdominal laparoscopic fenestration or retroperitoneal surgical exploration and ligation.

Need of vascular surgeon and comparison of value for anterior lumbar interbody fusion (ALIF) in lateral decubitus: Delphi consensus

BACKGROUND AND PURPOSE

Anterior lumbar approaches are recommended for clinical conditions that require interbody stability, spinal deformity corrections or a large fusion area. Anterior lumbar interbody fusion in lateral decubitus position (LatALIF) has gained progressive interest in the last years. The study aims to describe the current habit, the perception of safety and the perceptions of need of vascular surgeons according to experienced spine surgeons by comparing LatALIF to the standard L5-S1 supine ALIF (SupALIF).

METHODS

A two-round Delphi method study was conducted to assess the consensus, within expert spine surgeons, regarding the perception of safety, the preoperative planning, the complications management and the need for vascular surgeons by performing anterior approaches (SupALIF vs LatALIF).

RESULTS

A total of 14 experts voluntary were involved in the survey. From 82 sentences voted in the first round, a consensus was reached for 38 items. This included the feasibility of safe LatALIF without systematic involvement of vascular surgeon for routine cases (while for revision cases the involvement of the vascular surgeon is an appropriate option) and the appropriateness of standard MRI to evaluate the accessibility of the vascular window. Thirteen sentences reached the final consensus in the second round, whereas no consensus was reached for the remaining 20 statements.

CONCLUSIONS

The Delphi study collected the consensus on several points, such as the consolidated required experience on anterior approaches, the accurate study of vascular anatomy with MRI, the management of complications and the significant reduction of the surgical times of the LatALIF if compared to SupALIF in combined procedures. Furthermore, the study group agrees that LatALIF can be performed without the need for a vascular surgeon in routine cases.

Trends in Surgical Approach for Single-Level Lumbar Fusion Over the Past Decade

STUDY DESIGN

Retrospective Comparative Study.

OBJECTIVE

The purpose of this study was to characterize trends in surgical approach for single-level lumbar fusion over the past decade.

SUMMARY OF BACKGROUND DATA

The number of elective lumbar fusion cases performed is increasing annually. Several different surgical approaches exist for lumbar spinal fusion including novel anterior approaches developed in recent years. With ongoing innovation, trends in the utilization of common surgical approaches in recent years are unclear.

MATERIALS AND METHODS

A retrospective cohort study was conducted using the PearlDiver database (Fort Wayne, IN). Patients undergoing single-level lumbar fusion between 2010 and 2019 were identified using Current Procedural Technology codes and divided into 4 mutually exclusive cohorts based on surgical approach: (1) anterior-only, (2) anterior approach with posterior instrumentation, (3) posterolateral, and (4) posterior-only interbody. Trend analyses of surgical approach utilization over the last decade were performed with the Cochran-Armitage test to evaluate the 2-tailed null hypothesis that utilization of each surgical approach for single-level lumbar fusion remained constant.

RESULTS

A total of 53,234 patients met inclusion criteria and were stratified into 4 cohorts: anterior-only (n=5104), anterior with posterior instrumentation (n=23,515), posterolateral (n=5525), and posterior-only interbody (n=19,090). Trend analysis revealed the utilization of a posterior-only interbody approach significantly decreased from 36.7% to 29.2% (P<0.001), whereas the utilization of a combined anterior and posterior approach significantly increased from 45.8% to 50.4% (P<0.001). The utilization of an anterior-only approach also significantly increased from 7.9% to 10.5% (P<0.001).

CONCLUSIONS

Utilization of anterior-only and anterior with posterior instrumentation approaches for single-level lumbar fusion have been significantly increasing over the past decade while use of posterior-only interbody approach trended significantly downward. These data may be particularly useful for trainees and spine surgeons as new techniques and technology become available.

LEVEL OF EVIDENCE

Level III-retrospective cohort study.

Successful salvage strategy using anterior retroperitoneal approach in failed posterior lumbar interbody fusion. A retrospective analisys on lumbar lordosis and clinical outcome

OBJECTIVE

Posterior and transforaminal lumbar interbody fusion (PLIF, TLIF) are among the most popular surgical options for lumbar interbody fusion. If non-union occurs with consequent pain and reduced quality of life, revision surgery should correct any previous technical errors, avoiding further complications. The aim of this study was to analyze technical advantages, radiological and clinical outcomes of anterior approaches (ALIF) in case of failed PLIF or TLIF.

METHODS

Retrospective analysis of consecutive patients with persistent low back pain after failed PLIF/TLIF where salvage ALIF through an anterior retroperitoneal miniopen video-assisted technique was performed. Surgical, clinical and radiological data were analysed. Uni and multivariate statistical analysis were applied.

RESULTS

Thirty-six patients (average age: 47.1 years) were included. Mean follow-up was 34.4 months. In 30 patients (83.3%) a posterior surgical step was necessary. Non-union (86.1%), cage migration (5.5%), infection (8.3%) were the causes of revision surgery. In 22 patients (61.1%) the involved level was L5-S1, in 12 patients (33.4%) L4-L5, in 1 patient (2.7%) L3-L4. One patient (2.7%) had two levels (L4-L5 and L5-S1) involved. No major intraoperative complications were recorded. Significant correlation between clinical and radiological outcomes (L4-S1 and L5-S1 lordosis improvement) were observed (postoperative VAS and L5-S1, p = 0.038).

CONCLUSIONS

Salvage ALIF is a safe option that can significantly ameliorate residual pain achieving primary interbody stability with an ideal segmental lordosis according to pelvic parameters. The advantages of a naive anterior approach fulfils the main objectives of a revision surgery in order to significantly increase the chances of definitive fusion.

Lateral decubitus single position anterior-posterior (AP) fusion shows equivalent results to minimally invasive transforaminal lumbar interbody fusion at one-year follow-up

PURPOSE

This study compares perioperative and 1-year outcomes of lateral decubitus single position circumferential fusion (L-SPS) versus minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) for degenerative pathologies.

METHODS

Multicenter retrospective chart review of patients undergoing AP fusion with L-SPS or MIS TLIF. Demographics and clinical and radiographic outcomes were compared using independent samples t tests and chi-squared analyses with significance set at p < 0.05.

RESULTS

A total of 445 patients were included: 353 L-SPS, 92 MIS TLIF. The L-SPS cohort was significantly older with fewer diabetics and more levels fused. The L-SPS cohort had significantly shorter operative time, blood loss, radiation dosage, and length of stay compared to MIS TLIF. 1-year follow-up showed that the L-SPS cohort had higher rates of fusion (97.87% vs. 81.11%; p = 0.006) and lower rates of subsidence (6.38% vs. 38.46%; p < 0.001) compared with MIS TLIF. There were significantly fewer returns to the OR within 1 year for early mechanical failures with L-SPS (0.0% vs. 5.4%; p < 0.001). 1-year radiographic outcomes revealed that the L-SPS cohort had a greater LL (56.6 ± 12.5 vs. 51.1 ± 15.9; p = 0.004), smaller PI-LL mismatch (0.2 ± 13.0 vs. 5.5 ± 10.5; p = 0.004). There were no significant differences in amount of change in VAS scores between cohorts. Similar results were seen after propensity-matched analysis and sub-analysis of cases including L5-S1.

CONCLUSIONS

L-SPS improves perioperative outcomes and does not compromise clinical or radiographic results at 1-year follow-up compared with MIS TLIF. There may be decreased rates of early mechanical failure with L-SPS.

Anterior column reconstruction of the lumbar spine in the lateral decubitus position: anatomical and patient-related considerations for ALIF, anterior-to-psoas, and transpsoas LLIF approaches

PURPOSE

Circumferential (AP) lumbar fusion surgery is an effective treatment for degenerative and deformity conditions of the spine. The lateral decubitus position allows for simultaneous access to the anterior and posterior aspects of the spine, enabling instrumentation of both columns without the need for patient repositioning. This paper seeks to outline the anatomical and patient-related considerations in anterior column reconstruction of the lumbar spine from L1-S1 in the lateral decubitus position.

METHODS

We detail the anatomic considerations of the lateral ALIF, transpsoas, and anterior-to-psoas surgical approaches from surgeon experience and comprehensive literature review.

RESULTS

Single-position AP surgery allows simultaneous access to the anterior and posterior column and may combine ALIF, LLIF, and minimally invasive posterior instrumentation techniques from L1-S1 without patient repositioning. Careful history, physical examination, and imaging review optimize safety and efficacy of lateral ALIF or LLIF surgery. An excellent understanding of patient spinal and abdominal anatomy is necessary. Each approach has relative advantages and disadvantages according to the disc level, skeletal, vascular, and psoas anatomy.

CONCLUSIONS

A development of a framework to analyze these factors will result in improved patient outcomes and a reduction in complications for lateral ALIF, transpsoas, and anterior-to-psoas surgeries.

Anterior lumbar interbody fusion: single institutional review of complications and associated variables

BACKGROUND CONTEXT

As more patients undergo anterior lumbar interbody fusion (ALIF) procedures and more devices are created for that purpose, it is important to understand the complications that can arise and the variables that mitigate risk for major and minor complications.

PURPOSE

To assess complication rates after ALIF with or without posterior instrumentation and variables associated with increased likelihood of postoperative complications. We aim to provide this data as benchmarking to improve patient safety and surgical care.

STUDY DESIGN

A single-center retrospective cohort study.

PATIENT SAMPLE

All adult patients who underwent ALIF between 2017 and 2019 was performed OUTCOME MEASURES: Post-operative major and minor complications were evaluated.

METHODS

Complications were recorded and presented as percentages. Patient demographics, perioperative, and postoperative data were also collected and analyzed between patients who had no complications and those that had any complication. Subgroup analysis of surgical complications were performed by nonparametric Chi-square tests. Continuous variables were compared using Mann-Whitney U tests.

RESULTS

Ninty-five of three hundred sixty-two (26.2%) of patients experienced a minor or major complication. Among the most common complications found were surgical site infections (5.8%), neurological complications (4.1%), vascular complications (3.6%), and urinary tract infections (3.3%). Patients undergoing ALIF alone with post-operative complications had higher mean age, higher BMI, higher ASA status, and experienced higher estimated blood loss. Patients undergoing ALIF and posterior instrumentation with post-operative complications were more likely to have diabetes and had a higher ASA status. Patients with any complications from both groups had longer length of stay, discharge to a non-home setting and were more likely to be readmitted or return to the operating room.

CONCLUSION

Our study reveals variables associated with complications at our institution, including age of the patient, BMI, and ASA status leading to higher complications and greater LOS, higher readmission rates, and disposition to skilled facilities.

Single position lateral decubitus anterior lumbar interbody fusion (ALIF) and posterior fusion reduces complications and improves perioperative outcomes compared with traditional anterior-posterior lumbar fusion

BACKGROUND CONTEXT

Lateral decubitus single position anterior-posterior (AP) fusion utilizing anterior lumbar interbody fusion and percutaneous posterior fixation is a novel, minimally invasive surgical technique. Single position lumbar surgery (SPLS) with anterior lumbar interbody fusion (ALIF) or lateral lumbar interbody fusion (LLIF) has been shown to be a safe, effective technique. This study directly compares perioperative outcomes of SPLS with lateral ALIF vs. traditional supine ALIF with repositioning (FLIP) for degenerative pathologies.

PURPOSE

To determine if SPLS with lateral ALIF improves perioperative outcomes compared to FLIP with supine ALIF.

STUDY DESIGN/SETTING

Multicenter retrospective cohort study.

PATIENT SAMPLE

Patients undergoing primary AP fusions with ALIF at 5 institutions from 2015 to 2020.

OUTCOME MEASURES

Levels fused, inclusion of L4-L5, L5-S1, radiation dosage, operative time, estimated blood loss (EBL), length of stay (LOS), perioperative complications. Radiographic analysis included lumbar lordosis (LL), pelvic incidence (PI), and PI-LL mismatch.

METHODS

Retrospective analysis of primary ALIFs with bilateral percutaneous pedicle screw fixation between L4-S1 over 5 years at 5 institutions. Patients were grouped as FLIP or SPLS. Demographic, procedural, perioperative, and radiographic outcome measures were compared using independent samples t-tests and chi-squared analyses with significance set at p <.05. Cohorts were propensity-matched for demographic or procedural differences.

RESULTS

A total of 321 patients were included; 124 SPS and 197 Flip patients. Propensity-matching yielded 248 patients: 124 SPLS and 124 FLIP. The SPLS cohort demonstrated significantly reduced operative time (132.95±77.45 vs. 261.79±91.65 min; p <0.001), EBL (120.44±217.08 vs. 224.29±243.99 mL; p <.001), LOS (2.07±1.26 vs. 3.47±1.40 days; p <.001), and rate of perioperative ileus (0.00% vs. 6.45%; p =.005). Radiation dose (39.79±31.66 vs. 37.54±35.85 mGy; p =.719) and perioperative complications including vascular injury (1.61% vs. 1.61%; p =.000), retrograde ejaculation (0.00% vs. 0.81%, p =.328), abdominal wall (0.81% vs. 2.42%; p =.338), neuropraxia (1.61% vs. 0.81%; p =.532), persistent motor deficit (0.00% vs. 1.61%; p =.166), wound complications (1.61% vs. 1.61%; p =.000), or VTE (0.81% vs. 0.81%; p =.972) were similar. No difference was seen in 90-day return to OR. Similar results were noted in sub-analyses of single-level L4-L5 or L5-S1 fusions. On radiographic analysis, the SPLS cohort had greater changes in LL (4.23±11.14 vs. 0.43±8.07 deg; p =.005) and PI-LL mismatch (-4.78±8.77 vs. -0.39±7.51 deg; p =.002).

CONCLUSIONS

Single position lateral ALIF with percutaneous posterior fixation improves operative time, EBL, LOS, rate of ileus, and maintains safety compared to supine ALIF with prone percutaneous pedicle screws between L4-S1.

Is there a variance in complication types associated with ALIF approaches? A systematic review

Purpose

Anterior lumbar interbody fusion (ALIF) is a well-established alternative to posterior-based interbody fusion techniques, with approach variations, such as retroperitoneal, transperitoneal, open, and laparoscopic well described. Variable rates of complications for each approach have been enumerated in the literature. The purpose of this study was to elucidate the comparative rates of complications across approach type.

Methods

A systematic review of search databases PubMed, Google Scholar, and OVID Medline was made to identify studies related to complication-associated ALIF. PRISMA guidelines were utilised for this review. Meta-analysis was used to compare intraoperative and postoperative complications with ALIF for each approach.

Results

A total of 4575 studies were identified, with 5728 patients across 31 studies included for review following application of inclusion and exclusion criteria. Meta-analysis demonstrated the transperitoneal approach resulted in higher rates of retrograde ejaculation (RE) (p < 0.001; CI = 0.05–0.21) and overall rates of complications (p = 0.05; CI = 0.00–0.23). Rates of RE were higher at the L5/S1 intervertebral level. Rates of vessel injury were not significantly higher in either approach method (p = 0.89; CI =  − 0.04–0.07). Rates of visceral injury did not appear to be related to approach method. Laparoscopic approaches resulted in shorter inpatient stays (p = 0.01).

Conclusion

Despite the transperitoneal approach being comparatively underpowered, its use appears to result in a significantly higher rate of intraoperative and postoperative complications, although confounders including use of bone morphogenetic protein (BMP) and spinal level should be considered. Laparoscopic approaches resulted in shorter hospital stays; however, its steep learning curve and longer operative time have deterred surgeons from its widespread adaptation.

Development of machine learning and natural language processing algorithms for preoperative prediction and automated identification of intraoperative vascular injury in anterior lumbar spine surgery

BACKGROUND

Intraoperative vascular injury (VI) may be an unavoidable complication of anterior lumbar spine surgery; however, vascular injury has implications for quality and safety reporting as this intraoperative complication may result in serious bleeding, thrombosis, and postoperative stricture.

PURPOSE

The purpose of this study was to (1) develop machine learning algorithms for preoperative prediction of VI and (2) develop natural language processing (NLP) algorithms for automated surveillance of intraoperative VI from free-text operative notes.

PATIENT SAMPLE

Adult patients, 18 years or age or older, undergoing anterior lumbar spine surgery at two academic and three community medical centers were included in this analysis.

OUTCOME MEASURES

The primary outcome was unintended VI during anterior lumbar spine surgery.

METHODS

Manual review of free-text operative notes was used to identify patients who had unintended VI. The available population was split into training and testing cohorts. Five machine learning algorithms were developed for preoperative prediction of VI. An NLP algorithm was trained for automated detection of intraoperative VI from free-text operative notes. Performance of the NLP algorithm was compared to current procedural terminology and international classification of diseases codes.

RESULTS

In all, 1035 patients underwent anterior lumbar spine surgery and the rate of intraoperative VI was 7.2% (n=75). Variables used for preoperative prediction of VI were age, male sex, body mass index, diabetes, L4-L5 exposure, and surgery for infection (discitis, osteomyelitis). The best performing machine learning algorithm achieved c-statistic of 0.73 for preoperative prediction of VI (https://sorg-apps.shinyapps.io/lumbar_vascular_injury/). For automated detection of intraoperative VI from free-text notes, the NLP algorithm achieved c-statistic of 0.92. The NLP algorithm identified 18 of the 21 patients (sensitivity 0.86) who had a VI whereas current procedural terminologyand international classification of diseases codes identified 6 of the 21 (sensitivity 0.29) patients. At this threshold, the NLP algorithm had a specificity of 0.93, negative predictive value of 0.99, positive predictive value of 0.51, and F1-score of 0.64.

CONCLUSION

Relying on administrative procedural and diagnosis codes may underestimate the rate of unintended intraoperative VI in anterior lumbar spine surgery. External and prospective validation of the algorithms presented here may improve quality and safety reporting.

Anterior Lumbar Interbody Fusion (ALIF) L5-S1 with overpowering of posterior lumbosacral instrumentation and fusion mass: a reliable solution in revision spine surgery

BACKGROUND AND PURPOSE

In cases of spine surgical revisions of patients affected by sagittal malalignment, the restoration of the ideal lumbar lordosis (LL) is mandatory. ALIF procedures represent a powerful and effective approach to improve the LL in case of hypolordosis. This study evaluates the feasibility of ALIF to overpower posterior lumbar instrumentation and fusion mass in revision spine surgery and secondarily to estimate complications, clinical and radiological outcomes.

METHODS

This is a single-center retrospective analysis of prospectively collected data on the use of ALIF overpowering in cases of lumbosacral instrumentation and/or fusion. Demographic, comorbidity, corrective strategy adopted, surgical data, clinical and radiological results, and intraoperative and postoperative complications were recorded.

RESULTS

Twelve patients (3 male; 9 female) underwent overpowering ALIF L5-S1 were included in the study with a mean FU of 34.0 ± 13.4 months. In 10 cases, a posterior titanium instrumentation and fusion mass were present; in 2 patients, only a fusion mass was present. Indicators of pain and disability improved in all patients (p < 0.01). Sagittal realignment with the restoration of ideal spinopelvic parameters was obtained in all cases. One peritoneal lesion requiring intraoperative suture without sequelae, two cases of postoperative radiculopathy, and one posterior wound infection requiring surgical debridement and antibiotic therapy were reported.

CONCLUSIONS

Anterior implant of lordotic and hyperlordotic cages with increasing segmental lordosis is possible in the presence of posterior instrumentation and/or solid fusion mass. The biomechanical strength of this corrective technique can overcome posterior instrumentation and bone fusion resistance, therefore allowing a single-staged surgery for sagittal realignment.

Management of Vascular Complications during Anterior Lumbar Spinal Surgery Using Mini-Open Retroperitoneal Approach

BACKGROUND

Anterior retroperitoneal spine exposure has become increasingly performed for the surgical treatment of various spinal disorders. Despite its advantages, the procedure is not riskless and can expose to potentially life-threatening vascular lesions. The aim of this review is to report the vascular lesions that can happen during anterior lumbar spinal surgery using mini-open retroperitoneal approach and to describe their management.

METHODS

A systematic literature search was performed according to PRISMA to identify studies published in English between January 1980 and December 2019 reporting vascular complications during anterior lumbar spinal surgery with mini-open retroperitoneal approach. Three authors independently conducted the literature search on PubMed/Medline database using a combination of the following terms: "spinal surgery", "anterior lumbar surgery (ALS)", "anterior lumbar interbody fusion (ALIF)", "lumbar total disc replacement", "artificial disc replacement", "vascular complications", "vascular injuries". Vascular complications were defined as any peri-operative or post-operative lesions related to an arterial or venous vessel. The management of the vascular injury was extracted.

RESULTS

Fifteen studies fulfilled the inclusion criteria. Venous injuries were observed in 13 studies. Lacerations and deep venous thrombosis ranged from 0.8% to 4.3% of cases. Arterial lesions were observed in 4 studies and ranged from 0.4% to 4.3% of cases. It included arterial thrombosis, lacerations or vasospasms. The estimated blood loss was reported in 10 studies and ranged from 50 mL up to 3000 mL. Vascular complications were identified as a cause of abortion of the procedure in 2 studies, representing respectively 0.3% of patients who underwent ALS and 0.5% of patients who underwent ALIF.

CONCLUSION

Imaging pre-operative planning is of utmost importance to evaluate risk factors and the presence of anatomic variations in order to prevent and limit vascular complications. Cautions should be taken during the intervention when manipulating major vessels and routine monitoring of the limb oxygen saturation should be systematically performed for an early detection of arterial thrombosis. The training of the surgeon access remains a key-point to prevent and manage vascular complications during anterior lumbar spinal surgery with mini-open retroperitoneal.

ALIF in the correction of spinal sagittal misalignment. A systematic review of literature

PURPOSE

We aim at analysing the impact of anterior lumbar interbody fusion (ALIF) in restoring the main spinopelvic parameters, along with its potentials and limitations in correcting sagittal imbalance.

MATERIALS AND METHODS

The 2009 PRISMA flow chart was used to systematically review the literature; 27 papers were eventually selected. The following spinopelvic parameters were observed: pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), segmental lumbar lordosis (LLseg) and sagittal vertical axis (SVA). Papers reporting on hyperlordotic cages (HLC) were analysed separately. The indirect decompression potential of ALIF was also assessed. The clinical outcome was obtained by collecting visual analogue scale (VAS) for back and leg pain and Oswestry Disability Index (ODI) scores. Global fusion rate and main complications were collected.

RESULTS

PT, SS, LL, LLseg and SVA spinopelvic parameters all improved postoperatively by - 4.3 ± 5.2°, 3.9 ± 4.5°, 10.6 ± 12.5°, 6.7 ± 3.5° and 51.1 ± 44.8 mm, respectively. HLC were statistically more effective in restoring LL and LLseg (p < 0.05). Postoperative disc height, anterior disc height, posterior disc height and foraminal height, respectively, increased by 58.5%, 87.2%, 80.9% and 18.1%. Postoperative improvements were observed in VAS back and leg and ODI scores (p < 0.05). The global fusion rate was 94.5 ± 5.5%; the overall complication rate was 13%.

CONCLUSION

When managing sagittal imbalance, ALIF can be considered as a valid technique to achieve the correct spinopelvic parameters based on preoperative planning. This technique permits to obtain an optimal LL distribution and a solid anterior column support, with lower complications and higher fusion rates when compared to posterior osteotomies.

Functional and radiological outcome of anterior retroperitoneal versus posterior transforaminal interbody fusion in the management of single-level lumbar degenerative disease

OBJECTIVE

In this study the authors compared the anterior lumbar interbody fusion (ALIF) and posterior transforaminal lumbar interbody fusion (TLIF) techniques in a homogeneous group of patients affected by single-level L5–S1 degenerative disc disease (DDD) and postdiscectomy syndrome (PDS). The purpose of the study was to analyze perioperative, functional, and radiological data between the two techniques.

METHODS

A retrospective analysis of patient data was performed between 2015 and 2018. Patients were clustered into two homogeneous groups (group 1 = ALIF, group 2 = TLIF) according to surgical procedure. A statistical analysis of clinical perioperative and radiological findings was performed to compare the two groups. A senior musculoskeletal radiologist retrospectively revised all radiological images.

RESULTS

Seventy-two patients were comparable in terms of demographic features and surgical diagnosis and included in the study, involving 32 (44.4%) male and 40 (55.6%) female patients with an average age of 47.7 years. The mean follow-up duration was 49.7 months. Thirty-six patients (50%) were clustered in group 1, including 31 (86%) with DDD and 5 (14%) with PDS. Thirty-six patients (50%) were clustered in group 2, including 28 (78%) with DDD and 8 (22%) with PDS. A significant reduction in surgical time (107.4 vs 181.1 minutes) and blood loss (188.9 vs 387.1 ml) in group 1 (p < 0.0001) was observed. No significant differences in complications and reoperation rates between the two groups (p = 0.561) was observed. A significant improvement in functional outcome was observed in both groups (p < 0.001), but no significant difference between the two groups was found at the last follow-up. In group 1, a faster median time of return to work (2.4 vs 3.2 months) was recorded. A significant improvement in L5–S1 postoperative lordosis restoration was registered in the ALIF group (9.0 vs 5.0, p = 0.023).

CONCLUSIONS

According to these results, interbody fusion is effective in the surgical management of discogenic pain. Even if clinical benefits were achieved earlier in the ALIF group (better scores and faster return to work), both procedures improved functional outcomes at last follow-up. The ALIF group showed significant reduction of blood loss, shorter surgical time, and better segmental lordosis restoration when compared to the TLIF group. No significant differences in postoperative complications were observed between the groups. Based on these results, the ALIF technique enhances radiological outcome improvement in spinopelvic parameters when compared to TLIF in the management of adult patients with L5–S1 DDD.

The anterior-to-psoas approach for interbody fusion at the L5-S1 segment: clinical and radiological outcomes

OBJECTIVE

Over the last few decades, many surgical techniques for lumbar interbody fusion have been reported. The anterior-to-psoas (ATP) approach is theoretically supposed to benefit from the advantages of both anterior and lateral approaches with similar complication rates, even in L5-S1. At this segment, the anterior lumbar interbody fusion (ALIF) requires retroperitoneal dissection and retraction of major vessels, whereas the iliac crest does not allow the lateral transpsoas approach. This study aimed to investigate clinical-radiological outcomes and complications of the ATP approach at the L5-S1 segment in a single cohort of patients.

METHODS

This is a prospective single-center study, conducted from 2016 to 2019. Consecutive patients who underwent ATP at the L5-S1 segment for degenerative disc disease or revision surgery after previous posterior procedures were considered for eligibility. Complete clinical-radiological documentation and a minimum follow-up of 12 months were set as inclusion criteria. Clinical patient-reported outcomes, such as the visual analog scale for low-back pain, Oswestry Disability Index, and 36-Item Short Form Health Survey (SF-36) scores, as well as spinopelvic parameters, were collected preoperatively, 6 weeks after surgery, and at the last follow-up visit. Intraoperative and perioperative complications were recorded. The fusion rate was evaluated on CT scans obtained at 12 months postoperatively.

RESULTS

Thirty-two patients met the inclusion criteria. The mean age at the time of surgery was 57.6 years (range 44-75 years). The mean follow-up was 33.1 months (range 13-48 months). The mean pre- and postoperative visual analog scale (7.9 ± 1.3 vs 2.4 ± 0.8, p < 0.05), Oswestry Disability Index (52.8 ± 14.4 vs 22.9 ± 6.0, p < 0.05), and SF-36 (37.3 ± 5.8 vs 69.8 ± 6.1, p < 0.05) scores significantly improved. The mean lumbar lordosis and L5-S1 segmental lordosis significantly increased after surgery. The mean pelvic incidence-lumbar lordosis mismatch and pelvic tilt significantly decreased. No intraoperative complications and a postoperative complication rate of 9.4% were recorded. The fusion rate was 96.9%. One patient needed a second posterior revision surgery for residual foraminal stenosis.

CONCLUSIONS

In the present case series, ATP fusion for the L5-S1 segment has resulted in valuable clinical-radiological outcomes and a relatively low complication rate. Properly designed clinical and comparative trials are needed to further investigate the role of ATP for different L5-S1 conditions.

Impact of lordotic cages in the restoration of spinopelvic parameters after dorsal lumbar interbody fusion: a retrospective case control study

Purpose

Aim of this study was to compare the reconstruction of radiological sagittal spinopelvic parameters between lordotic (10°) and normal cages (0°) after dorsal lumbar spondylodesis.

Methods

This retrospective monocentric study included patients who received dorsal lumbar spondylodesis between January 2014 and December 2018. Inclusion criteria were degenerative lumbar diseases and mono- or bi-segmental fusions in the middle and lower lumbar region. Exclusion criteria were long-distance fusions (3 segments and more) and infectious and tumour-related diseases. The sagittal spinopelvine parameters (lumbar lordosis, segmental lordosis, sacral slope, pelvic incidence, and pelvic tilt) were measured pre- and post-operatively by two examiners at two different times. The patients were divided into 2 groups (group 1: lordotic cage, group 2: normal cage).

Results

One hundred thirty-eight patients (77 female, 61 male) with an average age of 66.6 ± 11.2 years (min.: 26, max.: 90) were included in the study based on the inclusion criteria. Ninety-two patients (66.7%) received 0° cages and 46 (33.3%) lordotic cages (10°). Segmental lordosis was increased by 4.2° on average in group 1 and by 6.5° in group 2 (p = 0.074). Average lumbar lordosis was increased by 2.1° in group 1 and by 0.6° in group 2 (p = 0.378). There was no significant difference in the correction of sagittal spinopelvic parameters. Inter- and inter-class reliability was between 0.887 and 0.956.

Conclusion

According to the results of our study, no advantages regarding sagittal radiological parameters for the implantation of a lordotic cage could be demonstrated.

[Comparison of the effectiveness of oblique lumbar interbody fusion and posterior lumbar interbody fusion for treatment of Cage dislodgement after lumbar surgery]

Objective

To compare the clinical and radiological effectiveness of oblique lumbar interbody fusion (OLIF) and posterior lumbar interbody fusion (PLIF) in the treatment of Cage dislodgement after lumbar surgery.

Methods

The clinical data of 40 patients who underwent revision surgery due to Cage dislodgement after lumbar surgery betweem April 2013 and March 2017 were retrospectively analyzed. Among them, 18 patients underwent OLIF (OLIF group) and 22 patients underwent PLIF (PLIF group) for revision. There was no significant difference between the two groups in age, gender, body mass index, intervals between primary surgery and revision surgery, number of primary fused levels, disc spaces of Cage dislodgement, and visual analogue scale (VAS) scores of low back pain and leg pain, Oswestry disability index (ODI), the segmental lordosis (SL) and disc height (DH) of the disc space of Cage dislodgement, and the lumbar lordosis (LL) before revision ( P>0.05). The operation time, intraoperative blood loss, hospital stay, and complications of the two groups were recorded and compared. The VAS scores of low back pain and leg pain were evaluated at 3 days, 3, 6, and 12 months after operation, and the ODI scores were evaluated at 3, 6, and 12 months after operation. The SL and DH of the disc space of Cage dislodgement and LL were measured at 12 months after operation and compared with those before operation. CT examination was performed at 12 months after operation, and the fusion of the disc space implanted with new Cage was judged by Bridwell grading standard.

Results

The intraoperative blood loss in the OLIF group was significantly less than that in the PLIF group ( t=-12.425, P=0.000); there was no significant difference between the two groups in the operation time and hospital stay ( P>0.05). Both groups were followed up 12-30 months, with an average of 18 months. In the OLIF group, 2 patients (11.1%) had thigh numbness and 1 patient (5.6%) had hip flexor weakness after operation; 2 patients (9.1%) in the PLIF group had intraoperative dural sac tear. The other patients' incisions healed by first intention without early postoperative complications. There was no significant difference in the incidence of complications between the two groups ( χ ²=0.519, P=0.642). The VAS scores of low back pain and leg pain, and the ODI score of the two groups at each time point after operation were significantly improved when compared with those before operation ( P<0.05); there was no significant difference between the two groups at each time point after operation ( P>0.05). At 12 months after operation, SL, LL, and DH in the two groups were significantly increased when compared with preoperative ones ( P<0.05); SL and DH in the OLIF group were significantly improved when compared with those in the PLIF group ( P<0.05), and there was no significant difference in LL between the two groups ( P>0.05). CT examination at 12 months after operation showed that all the operated disc spaces achieved bony fusion. According to the Bridwell grading standard, 12 cases were grade Ⅰ and 6 cases were grade Ⅱ in the OLIF group, and 13 cases were grade Ⅰ and 9 cases were grade Ⅱ in the PLIF group; there was no significant difference between the two groups ( Z=-0.486, P=0.627). During follow-up, neither re-displacement or sinking of Cage, nor loosening or fracture of internal fixation occurred.

Conclusion

OLIF and PLIF can achieve similar effectiveness in the treatment of Cage dislodgement after lumbar surgery. OLIF can further reduce intraoperative blood loss and restore the SL and DH of the disc space of Cage dislodgement better.

Anterior lumbar compared to oblique lumbar interbody approaches for multilevel fusions to the sacrum in adults with spinal deformity and degeneration

OBJECTIVE

In adult spinal deformity and degenerative conditions of the spine, interbody fusion to the sacrum often is performed to enhance arthrodesis, induce lordosis, and alleviate stenosis. Anterior lumbar interbody fusion (ALIF) has traditionally been performed, but minimally invasive oblique lumbar interbody fusion (OLIF) may or may not cause less morbidity because less retraction of the abdominal viscera is required. The authors evaluated whether there was a difference between the results of ALIF and OLIF in multilevel anterior or lateral interbody fusion to the sacrum.

METHODS

Patients from 2013 to 2018 who underwent multilevel ALIF or OLIF to the sacrum were retrospectively studied. Inclusion criteria were adult spinal deformity or degenerative pathology and multilevel ALIF or OLIF to the sacrum. Demographic, implant, perioperative, and radiographic variables were collected. Statistical calculations were performed for significant differences.

RESULTS

Data from a total of 127 patients were analyzed (66 OLIF patients and 61 ALIF patients). The mean follow-up times were 27.21 (ALIF) and 24.11 (OLIF) months. The mean surgical time was 251.48 minutes for ALIF patients and 234.48 minutes for OLIF patients (p = 0.154). The mean hospital stay was 7.79 days for ALIF patients and 7.02 days for OLIF patients (p = 0.159). The mean time to being able to eat solid food was 4.03 days for ALIF patients and 1.30 days for OLIF patients (p < 0.001). After excluding patients who had undergone L5-S1 posterior column osteotomy, 54 ALIF patients and 41 OLIF patients were analyzed for L5-S1 radiographic changes. The mean cage height was 14.94 mm for ALIF patients and 13.56 mm for OLIF patients (p = 0.001), and the mean cage lordosis was 15.87° in the ALIF group and 16.81° in the OLIF group (p = 0.278). The mean increases in anterior disc height were 7.34 mm and 4.72 mm for the ALIF and OLIF groups, respectively (p = 0.001), and the mean increases in posterior disc height were 3.35 mm and 1.24 mm (p < 0.001), respectively. The mean change in L5-S1 lordosis was 4.33° for ALIF patients and 4.59° for OLIF patients (p = 0.829).

CONCLUSIONS

Patients who underwent multilevel OLIF and ALIF to the sacrum had comparable operative times. OLIF was associated with a quicker ileus recovery and less blood loss. At L5-S1, ALIF allowed larger cages to be placed, resulting in a greater disc height change, but there was no significant difference in L5-S1 segmental lordosis.

Relationship of aortic bifurcation with sacropelvic anatomy: Application to anterior lumbar interbody fusion

INTRODUCTION

Various sacropelvic parameters such as the pelvic Incidence (PI) are used to predict ideal lumbar lordosis and aid surgical planning. The objective of this study was to establish the relationship between the location of the aortic bifurcation from the sacral promontory and sacropelvic measures including the PI.

MATERIALS AND METHODS

One hundred sixty five computed tomography (CT) scans obtained for major trauma including the entire spine were identified. Sacropelvic parameters including PI, sacral anatomic orientation, pelvic thickness (PTH), and sacral table angle were measured. Aortic bifurcation was identified on sagittal and coronal imaging and the distance from the sacral promontory (bifurcation-promontory distance [BPD]) measured (mm).

RESULTS

Mean age of the cohort was 44.3 years (SD 18.5; range 16-88 years); 61.8% male. The mean PI was 49.2° (SD 10.2°; range 30°-80°). The mean BPD was 66.4 mm (SD 13.1 mm; range 38.3-100 mm). In the majority, the bifurcation was at the level of the L4 vertebral body (72.7%). Only age (r = -.389; p < .0001) and PTH (r = .172; p = .027) correlated with the BPD to a significant degree. PI did not correlate with BPD (r = .061; p = .435). Linear regression analysis provided the following predictive equation: BPD = 34.3 mm + 0.30 × PTH.

CONCLUSION

This study demonstrates a lack of any meaningful correlation between sagittal pelvic parameters and the distance of the aortic bifurcation from the sacral promontory. Surgical planning for fusion surgery in the lumbar spine should include assessment of spinopelvic parameters and if anterior access to the lumbar disc(s) necessary, vascular anatomy should be carefully assessed independent of these measures.

The effect of vascular approach surgeons on perioperative complications in lateral transpsoas lumbar interbody fusions

BACKGROUND CONTEXT

Lateral lumbar interbody fusion (LLIF) is a popular technique used in spine surgery. It is minimally invasive, provides indirect decompression, and allows for coronal plane deformity correction. Despite these benefits, the approach to LLIF has been linked to complications associated with the lumbosacral plexus and vascular anatomy. As a result, vascular surgeons may be recruited for the exposure portion of the procedure.

PURPOSE

The purpose of this study was to compare exposure-related complication and postoperative (postop) neuropraxia rates between exposure (EXP) and spine surgeon only (SSO) groups while performing the approach for LLIF.

STUDY DESIGN/SETTING

Retrospective analysis of patients treated at a single institution.

PATIENT SAMPLE

Patients undergoing LLIF procedures between 2012 and 2018.

OUTCOME MEASURES

Operative time, estimated blood loss, fluoroscopy, length of stay (LOS), intra- and postoperative complications, and physiologic measures including pre- and postoperative motor examinations and unresolved neuropraxia.

METHODS

Patients who underwent LLIF were separated into EXP and SSO groups based on the presence or absence of vascular/general surgeon during the approach. The entire clinical history of patients with a decrease in pre- and postop motor examination was reviewed for the presence of neuropraxia. All other intra- and postop exposure-related complications were recorded for comparison. Propensity score matching (PSM) was performed to account for age, Charlson Comorbidity Index (CCI) percentage of LLIFs including L4-L5, and number of levels fused. Independent t test and chi-square analyses were used to identify significant differences between EXP and SSO groups. Statistical significance was set at p<.05.

RESULTS

Two hundred and seventy-five patients underwent LLIF procedures, 155 SSO and 120 EXP. Postoperatively, 26 patients (11.1%) experienced a drop in any Medical Research Council (MRC) score, and two patients (0.7%) experienced unresolved quadriceps palsies. The mean recovery time for MRC scores was 84.4 days. Other complications included 2 pneumothoraces (0.7%), 1 iliac vein injury (0.4%), 14 cases of ileus (5.1%), 3 pulmonary emboli (1.1%), 2 deep vein thrombosis (0.7%), 3 cases of abdominal wall paresis (1.1%), and one abdominal hematoma (0.4%). After PSM, demographics including age, gender, body mass index, CCI, levels fused, and operative time were similar between cohorts. Twenty patients had changes in pre- to postop motor scores (SSO 9.4%, EXP 12.4%, p>.05). Iliopsoas motor scores decreased at the highest rate (EXP 12.4%, SSO 8.2%, p>.05) followed by quadriceps (EXP 5.2%, SSO 4.7%, p>.05). One SSO patient's postop course was complicated by a foot drop but returned to baseline within 1 year. One patient in EXP group developed an unresolved quadriceps palsy (EXP 1.0%, SSO 0.0%, p>.05). Intraoperative exposure complications included one pneumothorax (EXP 1.0%, SSO 0.0%, p>.05). There were no differences in PE/DVT, Ileus, or LOS. In the EXP cohort, three patients experienced abdominal wall paresis (EXP 2.9%, SSO 0.00%, p=.246).

CONCLUSIONS

Comparing the LLIF exposures performed by EXP and SSO, we found no significant difference in the rates of complications. Additional research is needed to determine the etiology of the abdominal wall complications. In conclusion, neuropraxia- and approach-related complications are similarly low between exposure and spine surgeons.

Improving blood product utilization at an ambulatory surgery center: a retrospective cohort study on 50 patients with lumbar disc replacement

Background

There is minimal literature discussing anterior lumbar spine surgery in ambulatory surgery centers (ASCs). The main concern with the anterior approach to the lumbar spine is the potential for injury to great vessels. In our facility, there are two units of crossmatched blood available in addition to cell saver during the procedure. We retrospectively looked at 50 cases of lumbar total disc arthroplasty (TDA) in our ASC to determine utilization of blood products.

Methods

Medical records of 50 consecutive patients who underwent a lumbar TDA at a single ASC were reviewed. Surgeries completed at the ASC were all transferred from the post anesthesia care unit to an attached convalescence care center which allows up to 3 days of observation. Patients who had either a 1 or 2 level lumbar TDA were included in the study. Data consisting of demographics, American Society of Anesthesiologist Physical Status Classification System, length of stay, estimated blood loss, cell saver volume, transfusion, perioperative and postoperative complications were recorded. Preoperative, perioperative and postoperative medical records were reviewed.

Results

Medical records of 50 consecutive patients were reviewed. The mean age was 40.86 ± 9.45. Of these, 48 (96%) had a 1-level lumbar TDA, 1(2%) had a 2-level lumbar TDA, 1 (2%) had a lumbar TDA at L4/5 and an anterior lumbar interbody fusion at L5/S1. There were no mortalities; no patient had recorded perioperative complications. No patients received allogeneic blood transfusion, 4 (8%) were re-transfused with cell saver (2 receiving approximately 400 ml and 2 receiving approximately 200 ml of re-transfused blood). All 50 (100%) were discharged home in stable condition. We had 30-day follow-up data on 35 of 50 patients. Of the 35 patients reviewed, three (8.5%) of the patients were readmitted to the hospital. One additional patient was seen in the emergency department and discharged home after negative testing. No patient was readmitted for post-operative anemia.

Conclusion

The routine use of both cell saver and crossmatched blood in the operating suite for lumbar TDA may be an over-utilization of healthcare resources. In our review of 50 patients, we had no need for transfusion of allogeneic packed red blood cells (PRBCs) and only four of the 50 patients had enough blood output for re-transfusion from the cell saver. This opens the conversation for alternatives to crossmatched PRBCs being held in the operating room. Such alternatives may be the use of cell salvage, only type O blood in a cooler for each patient or keeping type O blood on constant hold in ASCs.

Complications Associated With Minimally Invasive Anterior to the Psoas (ATP) Fusion of the Lumbosacral Spine

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To analyze complications associated with minimally invasive anterolateral retroperitoneal antepsoas lumbosacral fusion (MIS-ATP).

SUMMARY OF BACKGROUND DATA

MIS-ATP provides anterolateral access to the lumbar spine allowing for safe anterior lumbar interbody fusions between T12-S1. Anecdotally, many surgeons believe that ATP approach is not feasible at L5-S1 level, predisposing to catastrophic vascular injuries. This approach may help overcome limitations associated with conventional straight anterior lumbar interbody fusions, MIS lateral lumbar interbody fusion, and oblique lateral interbody fusion.

METHODS

A detailed retrospective chart review of patients who had underwent MIS-ATP approach for lumbar fusion between T12-S1 was performed. Available electronic data from surgeries performed between January 2008 and March 2017 was carefully screened for surgical patients treated for spondylolisthesis, spondylosis, stenosis, sagittal, and/or coronal deformity. Detailed review of electronic medical records including operative notes, progress notes, discharge summaries, laboratory results, imaging reports, and clinic visit notes performed by a single independent reviewer not involved in patient care for documented complications. A complication is defined as any adverse event related to the index spine procedure for which patient required specific intervention or treatment.

RESULTS

Nine hundred forty patients with a total of 2429 interbody fusion levels performed via MIS-ATP were identified during the study period. Sixty-seven patients (7.2%) sustained one or more complications during the perioperative period, of which 25.5% were surgical and 74.5% were medical. Overall, 78 (8.2%) surgical complications pertaining to the index procedure were noted during a postoperative period of 1 year from the date of surgery. No major vascular or direct visceral injuries were encountered.

CONCLUSIONS

MIS-ATP approach provides a safe access to anterolateral interbody fusions between T12-S1. The ATP approach is performed by the spine surgeon, does not require neuromonitoring, and warrants minimal to no psoas muscle retraction resulting in significantly reduced postoperative thigh pain and rare neurologic injuries. Additionally, the direct and clear visualization of the retroperitoneal vasculature provided by the ATP approach minimizes the risk of inadvertent vascular injury.

LEVEL OF EVIDENCE

4.

The rate of fusion for stand-alone anterior lumbar interbody fusion: a systematic review

BACKGROUND

Anterior lumbar interbody fusion (ALIF) has been used for treatment of a variety of spinal conditions including degenerative disc disorders and low-grade spondylolisthesis. Expected fusion rate of stand-alone ALIF constructs is currently unclear. The aim of this study was to examine the fusion rate for ALIF without supplemental posterior fusion or instrumentation (stand-alone ALIF).

METHODS

We queried the MEDLINE, COCHRANE, and EMBASE databases for all literature related to spine fusion rates using a stand-alone ALIF procedure with a publication cutoff date of July 19, 2018. Supplementary combinations of search terms included spine, fusion, fixation, rate(s), and arthrodesis. ALIF surgery was considered stand-alone when not paired with supplemental posterior fusion or posterior spinal instrumentation. Nonhuman and non-English publications were excluded. Cohort fusion rate differences were calculated using Student t test with significance assigned if p value was less than .05.

RESULTS

Title and abstract level review required assessing 840 unique publications. Across the 55 studies that met the inclusion criteria of this systematic review, 5,517 patients and 6,303 vertebral levels were fused. The overall weighted average patient fusion rate following stand-alone ALIF was 88.2% (range: 16.6%-100%). In the 31 studies with at least 50 subjects, the weighted average fusion rate following stand-alone ALIF was 88.6% (range: 57.5%-99.0%). Use of anterior fixation plate devices yielded a fusion rate of 94.2%. Newer zero-profile interbody implants had a fusion rate of 89.2%. Fusion rates were lower in studies with 50% or more subjects having positive smoking and worker's compensation status, however these results were found to be statistically insignificant (p>.05). Fusion rate for subjects in the eight rhBMP-2 study groups was 94.4% (n=889) compared with 84.8% (n=3,102) in 38 study groups without rhBMP-2 used.

CONCLUSIONS

Based on the available data, stand-alone ALIF procedures yield high fusion rates overall. Fusion failure and pseudoarthrosis rates are higher in study populations involving a high percentage of smokers or positive workers compensation status. Allograft utilization does not significantly improve fusion rate when compared with autograft in stand-alone ALIF constructs.

Outcomes of direct lateral interbody fusion (DLIF) in an Australian cohort

Background

Direct lateral interbody fusion (DLIF) mitigates many of the vascular complications and bony resections associated with other interbody fusion techniques. However, there are concerns regarding postoperative neural complications and that indirect decompression of the foramen has not been consistently demonstrated. This study prospectively assessed the clinical and radiological outcomes and the complication rates of the DLIF approach.

Methods

A prospective review was conducted of the first 50 consecutive DLIF cases of a single neurosurgeon between 2010 and 2014. Clinical outcomes were assessed using Visual Analogue Scale (VAS), Oswestry Disability Index (ODI) and Roland Morris Disability Questionnaire (RMDQ) surveys. Radiological outcomes, including spondylolisthesis, disc height, local disc angle, lumbar lordosis and foraminal height and width, were measured using Surgimap Spine software at the preoperative, 6 weeks, 6 months, and 12 months postoperative follow-up. Complication rates were also reported.

Results

A total of 50 patients (84 levels) were treated with DLIF. The mean patient age was 68.2±9.8 years and 62.0% were female. At latest follow-up, mean VAS pain score improved from 7.7±1.5 to 1.9±0.9 (P<0.0001), mean ODI improved from 42.1±14.5 to 16.9±6.7 (P<0.0001) and mean RMDQ score improved from 12.1±5.2 to 6.2±4.7 (P<0.0001). Mean spondylolisthesis reduced from 7.5%±6.5% to 1.3%±1.1% at 6 weeks (P<0.0001), 0.95%±0.74% at 6 months (P<0.0001) and recurred to 1.9%±1.7% at 12 months postoperatively (P=0.0006). Mean anterior disc height improved from 7.3±3.2 to 11.6±2.5 mm at 6 weeks (P<0.0001), 12.2±3.3 mm at 6 months (P<0.0001) and 9.8±2.1 mm at 12 months (P=0.0032) postoperatively. Mean posterior disc height improved from 4.4±2.0 to 6.8±2.1 mm at 6 weeks (P<0.0001), 6.6±2.5 mm at 6 months (P=0.0003), and 5.9±1.4 mm at 12 months (P=0.0039) postoperatively. Mean local disc angle improved from 7.0°±3.7° to 9.2°±3.3° at 6 weeks (P=0.0072), 10.4°±3.9° at 6 months (P=0.0013) and 8.2°±2.9° at 12 months (P=0.2487) postoperatively. No significant postoperative changes in lumbar lordosis were observed. Mean foraminal height improved from 18.3±3.5 to 21.5±3.9 mm at 6 weeks (P=0.0004), 20.6±3.4 mm at 6 months (P=0.0266), and 18.7±1.9 mm at 12 months (P=0.8021) postoperatively. Mean foraminal width improved from 7.9±2.0 to 10.2±2.8 mm at 6 weeks (P=0.0001), 9.4±2.6 mm at 6 months (P=0.0219) and 8.3±1.6 mm at 12 months (P=0.5734) postoperatively. Fusion rate at 6 and 12 months was 62.2% and 89.2%, respectively. A total of 6 patients (12%) had postoperative complications. Three patients (6%) had pain-related psoas muscle weakness and 3 patients (6%) had sensory neural complications that had resolved entirely by 8 and 16 weeks postoperatively, respectively.

Conclusions

The study provides encouraging short and medium-term clinical and radiological results for DLIF. In this patient series, there was a low complication rate with no permanent neural injury reported.

Abdominal Lymphocele Following Anterior Lumbar Interbody Fusion: A Case Report

Anterior lumbar interbody fusion (ALIF) is commonly utilized for surgical management of degenerative lumbar pathology. Although it is a reasonably safe procedure, it can potentially lead to major complications in case of neurovascular injuries. Occurrence of lymphocele after an ALIF is however rare.

We present a case of a rare abdominal lymphocele in a 56-year-old man who underwent L3-S1 ALIF and subsequently developed an abdominal lymphocele. A lymphocele can manifest in numerous ways which can affect and possibly delay diagnoses. In addition to a high index of suspicion, numerous tests such as imaging studies, fluid analysis, gram stain and culture are used to confirm the diagnosis.

Various options exist for the treatment of lymphoceles, including laparoscopic marsupialization, ultrasound-guided aspiration, sclerotherapy, peritoneal window, and external drainage. Timely diagnosis and treatment of a lymphocele results in a successful resolution in most cases.

A new "keyhole" approach for multilevel anterior lumbar interbody fusion: the perinavel approach-technical note and literature review

PURPOSE

The purpose of this study is to evaluate the feasibility and the safety of a new skin incision for minimally invasive anterior lumbar interbody fusion (ALIF): the perinavel incision.

METHODS

Demographic and clinical data from patients who underwent ALIF with the perinavel incision were collected. Indications to surgery, preoperative symptoms, radiological data, number of treated levels, intraoperative and early postoperative complications and wound-related problems were analysed.

RESULT

Ninety-seven patients underwent ALIF with this new skin incision. One hundred fifty-seven levels were treated (mean 1.7 level per patient) being L4-L5 the most frequently treated. Intraoperative complications were represented only by the venous injury with a rate of 3.09% (3 cases). Postoperative complications were all linked to skin incision issues: a case of wound dehiscence and a case of superficial infection. No case of skin necrosis occurs at 3-month follow-up.

CONCLUSIONS

In this paper, the perinavel skin incision was demonstrated to be as safe as traditional approaches for ALIF. Furthermore, with this incision it is possible to perform multilevel (L3-S1) ALIF, which means a good option in minimally invasive surgery as well as revision surgery. These slides can be retrieved under Electronic Supplementary Material.

Sexual activity after spine surgery: a systematic review

INTRODUCTION

Sexual function is an important determinant of quality of life, and factors such as surgical approach, performance of fusion, neurological function and residual pain can affect it after spine surgery. Our aim was to perform a systematic review to collate evidence regarding the impact of spine surgery on sexual function.

METHODS

A systematic review of studies reporting measures of sexual function, and incidence of adverse sexual outcomes (retrograde ejaculation) after major spine surgery was done, regardless of spinal location. Pubmed (MEDLINE) and Google Scholar databases were queried using the following search words "Sex", "Sex life", "Sexual function", "Sexual activity", "retrograde ejaculation", "Spine", "Spine surgery", "Lumbar surgery", "Lumbar fusion", "cervical spine", "cervical fusion", "Spinal deformity", "scoliosis" and "Decompression". All articles published between 1997 and 2017 were retrieved from the database. A total of 81 studies were included in the final review.

RESULTS

Majority of the studies were retrospective case series and were low quality (Level IV) in evidence. Anterior lumbar approaches were associated with a higher incidence of retrograde ejaculation, especially with the utilization of transperitoneal laparoscopic approach. There is inconclusive evidence on the preferred sexual position following fusion, and also on the impact of BMP-2 usage on retrograde ejaculation/sexual dysfunction.

CONCLUSION

Despite limited evidence from high-quality articles, there is a general trend towards improvement of sexual activity and function after spine surgery. Future studies incorporating specific assessments of sexual activity will be required to address this important determinant of quality of life so that appropriate pre-operative counselling can be done by providers. These slides can be retrieved under Electronic Supplementary Material.

Understanding Retroperitoneal Anatomy for Lateral Approach Spine Surgery

Lateral approach spine surgery provides effective interbody stabilization, and correction and indirect neural decompression with minimal-incision and less invasive surgery compared with conventional open anterior lumbar fusion. It may also avoid the trauma to paraspinal muscles or facet joints found with transforaminal lumbar interbody fusion and posterior lumbar interbody fusion. However, because lateral approach surgery is fundamentally retroperitoneal approach surgery, it carries potential risk to intra- and retroperitoneal structures, as seen in a conventional open anterior approach. There is an innovative lateral approach technique that reveals different anatomical views; however, it requires reconsideration of the traditional surgical anatomy in more detail than a traditional open anterior approach. The retroperitoneum is the compartmentalized space bounded anteriorly by the posterior parietal peritoneum and posteriorly by the transversalis fascia. The retroperitoneum is divided into three compartments by fascial planes: anterior and posterior pararenal spaces and the perirenal space. Lateral approach surgery requires mobilization of the peritoneum and its content and accurate exposure to the posterior pararenal space. The posterior pararenal space is confined anteriorly by the posterior renal fascia, anteromedially by the lateroconal fascia, and posteriorly by the transversalis fascia. The posterior renal fascia, the lateroconal fascia or the peritoneum should be detached from the transversalis fascia and the psoas fascia to allow exposure to the posterior pararenal space. The posterior pararenal space, however, does not allow a clear view and identification of these fasciae as this relationship is variable and the medial extent of the posterior pararenal space varies among patients. Correct anatomical recognition of the retroperitoneum is essential to success in lateral approach surgery. Spine surgeons must be aware that the retroperitoneal membrane and fascia is multilayered and more complex than is commonly understood. Preoperative abdominal images would facilitate more efficient surgical considerations of retroperitoneal membrane and fascia in lateral approach surgery.

Anterior lumbar interbody fusion (ALIF) as an option for recurrent disc herniations: a systematic review and meta-analysis

Background

Recurrent intervertebral disc herniation is a relatively common occurrence after primary discectomy for lumbar intervertebral disc herniation. For recurrent herniations after repeat discectomies, a growing body of evidence suggests that fusion is effective in appropriately selected cases. Theoretically, anterior lumbar interbody fusion (ALIF) allows for comprehensive discectomy, less trauma to spinal nerves and paraspinal muscles and avoidance of the disadvantages of repeat posterior approaches. However, ALIF has also been associated with risk of vascular injury and retrograde ejaculation. This current systematic review and meta-analysis aims to assess the viability of ALIF as a surgical treatment for recurrent disc herniations.

Methods

Seven studies were identified from six electronic databases and secondary reference lists. Pre-defined endpoints were extracted from the included studies and meta-analyzed.

Results

For the 181 patients from included studies, ALIF resulted in significant average improvements in Oswestry Disability Index (ODI) scores (50.49%, P<0.001), Visual Analogue Scale (VAS) back pain scores (47.85%, P<0.001) and VAS leg pain scores (37.00%, P<0.001). Average blood loss was acceptable at 122 mL (P<0.001) and average operation duration was 89 minutes (P<0.001). Average hospital stay was 5.28 days (P<0.001). Only 22 perioperative complications were reported, with subsidence the most commonly reported complication.

Conclusions

Pooled evidence suggests that ALIF is a feasible approach for the treatment of recurrent disc herniations, demonstrating significant improvements in back and leg pain and minimal complications. These findings warrant further investigation in large prospective registries and multi-center studies.

Evaluating Outcomes of Stand-Alone Anterior Lumbar Interbody Fusion: A Systematic Review

BACKGROUND

Stand-alone anterior lumbar interbody fusion (ALIF) is an effective surgical approach for selected spinal pathologies. It avoids the morbidity and complications associated with instrumented ALIF, such as plate fixation and the traditionally used posterior approach. Despite improved disc space visualization and clearance, the associated posterior instability and increased risk of nonfusion present major challenges to this approach. The integral cage design aims to address these challenges by providing the necessary stabilization through intracorporeal screws. However, there is limited and controversial data available for stand-alone ALIF and integral cage fixation. To our knowledge, this is the first systematic review to evaluate recent findings on outcomes of stand-alone ALIF devices to explore areas of controversy and identify directions for future research.

METHODS

Two reviewers conducted independent, systematic literature searches for appropriate studies in 5 electronic databases as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies were filtered by the use of specified selection criteria, particularly exclusion of studies with supplementary fixation to ALIF and studies published before the year 2000. A total of 17 studies met the criteria, and their data were comprehensively extracted and analyzed.

RESULTS

The current literature is supportive of stand-alone ALIF due to acceptable clinical outcomes, promising fusion rates and disc height restoration. However, data and outcomes remain preliminary, and there are numerous areas of controversy.

CONCLUSIONS

There is evidence for the efficacy and safety of stand-alone ALIF. However, the extent of improvement based on specific indications for surgery remains unclear. Further investigation utilizing more methodologically rigorous studies of long-term outcomes is necessary to address these issues.

Worker's Compensation Status and Outcomes Following Anterior Lumbar Interbody Fusion: Prospective Observational Study

BACKGROUND

Anterior lumbar-interbody fusion (ALIF) is a commonly performed procedure for degenerative spinal disorders with reasonable clinical and safety outcomes, although there is limited evidence regarding the impact of ALIF in patients receiving worker's compensation (WC) compared with those without. The aim of our study is to identify whether WC status affects the clinical outcome and rates of complication following ALIF surgery in a prospective cohort.

METHODS

We followed prospectively 114 consecutive patients undergoing ALIF surgery from 2012-2014. Patients were categorized into 2 groups: those with worker's compensation (WC) (n = 24) and those without (n = 90). Patients were evaluated preoperative and postoperatively. Outcome measures included Short Form-12 (SF-12), Oswestry Disability Index (ODI), surgical complications, and subsidence.

RESULTS

In terms of baseline traits, the WC group had a significantly higher proportion of class III/IV obesity patients, who were younger (46.3 vs. 60.2 years) compared with non-WC. There were no significant differences in fusion rates or preoperative or postoperative disk height. No significant differences were found for hospital stay, blood loss, or operation duration. Similar rates of complications were found between WC versus non-WC cohorts. No significant difference was noted in clinical improvement between the 2 cohorts with SF-12 PCS, SF-12 MCS, or ODI (P = 0.232). No significant difference was found in the proportion of patients achieving minimal clinically important difference for SF-12 PCS/MCS or ODI.

CONCLUSIONS

In our prospective cohort, there were no significant differences found between WC versus non-WC patients in terms of fusion rates, complications, clinical outcomes, or proportion of patients achieving minimal clinically important difference.