Comparative analysis of 3 surgical strategies for adult spinal deformity with mild to moderate sagittal imbalance

Revision Strategy for Proximal Junctional Failure: Combined Effect of Proximal Extension and Focal Correction

Study designRetrospective review of a prospectively-collected multicenter database.ObjectivesThe objective of this study was to determine optimal strategies in terms of focal angular correction and length of proximal extension during revision for PJF.Methods134 patients requiring proximal extension for PJF were analyzed in this study. The correlation between amount of proximal junctional angle (PJA) reduction and recurrence of proximal junctional kyphosis (PJK) and/or PJF was investigated. Following stratification by the degree of PJK correction and the numbers of levels extended proximally, rates of radiographic PJK (PJA >28° & ΔPJA >22°), and recurrent surgery for PJF were reported.ResultsBefore revision, mean PJA was 27.6° ± 14.6°. Mean number of levels extended was 6.0 ± 3.3. Average PJA reduction was 18.8° ± 18.9°. A correlation between the degree of PJA reduction and rate of recurrent PJK was observed (r = -.222). Recurrent radiographic PJK (0%) and clinical PJF (4.5%) were rare in patients undergoing extension ≥8 levels, regardless of angular correction. Patients with small reductions (<5°) and small extensions (<4 levels) experienced moderate rates of recurrent PJK (19.1%) and PJF (9.5%). Patients with large reductions (>30°) and extensions <8 levels had the highest rate of recurrent PJK (31.8%) and PJF (16.0%).ConclusionWhile the degree of focal PJK correction must be determined by the treating surgeon based upon clinical goals, recurrent PJK may be minimized by limiting reduction to <30°. If larger PJA correction is required, more extensive proximal fusion constructs may mitigate recurrent PJK/PJF rates.

Combined anterior-posterior versus posterior only approach for surgical management of adult spinal deformity: a systematic review and meta-analysis of comparative studies

PURPOSE

The purpose of this systematic review and meta-analysis was to examine the clinical outcomes and complication rates for fusion procedures of adult spinal deformity (ASD) performed via an anterior-posterior approach as compared to a posterior-only approach to guide surgical decision-making. Numerous surgical techniques exist for operative management of ASD; however, no systematic review and meta-analysis exists comparing combined anterior-posterior approaches to posterior-only approach, despite significant interest in the current literature.

METHODS

Four databases were used to collect articles from database inception until September 9th, 2023. Inclusion criteria was articles that examined both anterior-posterior or posterior only surgical approach, adult patients, comparative studies, and articles in English.

RESULTS

Seven comparative articles met the inclusion criteria. Included patients had a frequency weighted (FW) mean age of 60.2 ± 5.1 years and a FW mean follow-up of 40.4 ± 12.5 months. Qualitative data did not favor either group in terms of length of stay, radiographic outcomes, or functional outcomes. There was a total of 306 complications in the Anterior-Posterior group with a complication rate per patient of 1.0 ± 0.9 complications whereas there was a total of 380 complications in the Posterior Only group with a complication rate per patient of 1.0 ± 1.2 complications. Meta-analysis of specific complications found no significant difference in revision rate, dural tear rate, neurological complication rate, infection rate, or pseudoarthrosis rate.

CONCLUSION

Surgical management for ASD may provide comparable results in terms of surgical parameters, radiographic outcomes, functional outcomes, and complication rates, irrespective of surgical approach.

Two-Year Radiological Outcome of Adult Spinal Deformity Treated with Lumbar Pedicle Subtraction Osteotomy or Posterior Lumbar Interbody Fusion: A Propensity Score-Matched Analysis

OBJECTIVE

The purpose of this retrospective cohort study was to compare the 2-year radiological outcome and revision rates in patients with adult spinal deformity treated with either pedicle subtraction osteotomy (PSO) or posterior lumbar interbody fusion (PLIF), when PLIF was used to improve sagittal balance.

METHODS

In 2016, PLIF was introduced at our institution as an alternative method when restoring lumbar lordosis. We analyzed 2 cohorts of patients with adult spinal deformity undergoing either PSO in 2010-2015 or PLIF in 2016-2020, retrospectively. The rate of mechanical failure was analyzed using competing risk analysis.

RESULTS

We included 141 patients (111 PSO and 30 PLIF). After propensity score matching, 60 patients undergoing PSO and 30 patients undergoing PLIF were included. Baseline demographics were comparable between groups but radiographic parameters differed significantly on Sacral Slope; 23 ± 13 versus 28 ± 10, and segmental lordosis; 7 ± 14° versus. 14 ± 13° (P-value < 0.05) for PSO and PLIF, respectively. Postoperatively, PSO patients had a larger global lordosis; 54 ± 12 versus 48 ± 14 and segmental lordosis of 33 ± 10 versus 26 ± 10 (P-value < 0.05), than PLIF patients. Competing risk analysis showed a cumulative incidence of revision surgery of 38.3% (95% CI 28-43) versus 16.7 (95% CI 3-30), (P-value < 0.05) for PSO, and PLIF at 2-year follow-up.

CONCLUSIONS

A significantly lower revision rate was seen for patients undergoing PLIF compared with PSO at a 2-year follow-up. A satisfactory sagittal correction was obtained for both groups regardless of the procedure. Thus, PLIF could be a viable option in selected cases.

Readmission rate after adult scoliosis surgery on primary cases over 45 years-old with long term follow-up

PURPOSE

Scoliosis surgery is becoming increasingly frequent. Rate of readmission is little discussed in the literature. It is an interesting data for the patient's information and for public authorities to calculate cost-effectiveness. Aim of the study was to evaluate rate and causes of short and long-term readmissions in patients > 45 years old operated on for a scoliosis primary cases, then to look for predictors of these readmissions.

METHODS

In this monocentric retrospective cohort study, over 45 years-old scoliosis primary cases operated on between 2015 and 2018 and with a minimum of 2 years follow-up were included. The number of readmissions and their causes were analyzed. Rehospitalized patients (RH) were then compared to non-rehospitalized patients (NRH). Risk factors were sought using a multivariate analysis by logistic regression.

RESULTS

105 patients were included (90% female; 64 ± 8 years). 56% were readmitted at least once. Main cause of readmission as pseudarthrosis (70%). Among the RH patients, fifty-eight required at least one revision. We found no significant difference between RH and NRH, apart from the rate of immediate post-operative medical complications which was significantly higher in RH (17% (n = 11) vs. 4% (n = 2), p = 0.04). According to multivariate analysis, BMI and age were found as predictors of readmission of mechanical origin, and BMI for readmissions of septic origin.

CONCLUSION

The readmission rate after scoliosis surgery was 56%. The main cause was pseudarthrosis. Rehospitalized patients had more immediate post-operative medical complications. The elderly and overweight patients are more likely to be readmitted for mechanical or septic reasons.

Anterior Lumbar Interbody Fusion as a Supplement to Posterior Instrumentation in Adult Spinal Deformity Patients: A Pilot Randomized Study With a Median of Eight Years of Follow-Up

Aim We aim to assess the long-term revision rates in patients with adult spinal deformity (ASD) undergoing posterior instrumentation with or without supplemental anterior lumbar interbody fusion (ALIF) with a median of eight years of follow-up. Materials and methods Based on a previous pilot randomized controlled trial (RCT) from 2012, all previous participants were invited to a clinical and radiographic follow-up. Full medical records from the total cohort were reviewed from the time of operation to the follow-up, and information on revision surgery due to mechanical failure was obtained and compared between the groups. Results Of the original 17 patients included in the RCT, 15 were available for follow-up and 10 attended the clinical and radiographic examination. A retrospective review was performed of the entire original cohort. The median age at follow-up was 67 (61-71) years, and the median follow-up time was 7.7 (5.1-8.8) years. Revision rates among ALIF patients were three out of seven (43%) and eight out of 10 (80%) among non-ALIF patients with pseudoarthrosis and rod breakage being the main cause. Time to failure was longer in ALIF patients with a median of 47 (28-53) months compared with non-ALIF patients with a median of 26 (9-31) months. Conclusion This study revealed a lower rate of revision surgery and a longer time to failure in patients undergoing ASD surgery with supplemental ALIF compared with posterior instrumentation alone. Further studies with a larger sample size are needed to make conclusions on the effect of a supplemental ALIF to posterior instrumentation on lowering the risk of mechanical failure in patients with adult spinal deformity.

A comparative cohort study of surgical approaches for adult spinal deformity at a minimum 2-year follow-up

STUDY DESIGN

This study was a retrospective multi-center comparative cohort study.

MATERIALS AND METHODS

A retrospective institutional database of operative adult spinal deformity patients was utilized. All fusions > 5 vertebral levels and including the sacrum/pelvis were eligible for inclusion. Revisions, 3 column osteotomies, and patients with < 2-year clinical follow-up were excluded. Patients were separated into 3 groups based on surgical approach: 1) posterior spinal fusion without interbody (PSF), 2) PSF with interbody (PSF-IB), and 3) anteroposterior (AP) fusion (anterior lumbar interbody fusion or lateral lumbar interbody fusion with posterior screw fixation). Intraoperative, radiographic, and clinical outcomes, as well as complications, were compared between groups with ANOVA and χ2 tests.

RESULTS

One-hundred and thirty-eight patients were included for study (PSF, n = 37; PSF-IB, n = 44; AP, n = 57). Intraoperatively, estimated blood loss was similar between groups (p = 0.171). However, the AP group had longer operative times (547.5 min) compared to PSF (385.1) and PSF-IB (370.7) (p < 0.001). Additionally, fusion length was shorter in PSF-IB (11.4) compared to AP (13.6) and PSF (12.9) (p = 0.004). There were no differences between the groups in terms of change in alignment from preoperative to 2 years postoperative. There were no differences in clinical outcomes. While postoperative complications were largely similar between groups, operative complications were higher in the AP group (31.6%) compared to the PSF (5.4%) and PSF-IB (9.1) groups (p < 0.001).

CONCLUSION

While there were differences in intraoperative outcomes (operative time and fusion length), there were no differences in postoperative clinical or radiographic outcomes. AP fusion was associated with a higher rate of operative complications.

Pedicle Subtraction Osteotomy Versus Multilevel Anterior Lumbar Interbody Fusion and Lateral Lumbar Interbody Fusion in the Treatment of Adult Spinal Deformity: Trends, Outcomes, and Cost

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim of this study was to compare the outcomes of pedicle subtraction osteotomy (PSO) with multilevel anterior lumbar interbody fusion (ALIF) and lateral lumbar interbody fusion (LLIF) in posterior long-segment fusion.

BACKGROUND

PSO and ALIF/LLIF are 2 techniques used to restore lumbar lordosis and correct sagittal alignment, with each holding its unique advantages and disadvantages. As there are situations where both techniques can be employed, it is important to compare the risks and benefits of both.

PATIENTS AND METHODS

Patients aged 18 years or older who underwent PSO or multilevel ALIF/LLIF with posterior fusion of 7-12 levels and pelvic fixation were identified. 1:1 propensity score was used to match PSO and ALIF/LLIF cohorts for age, sex, and relevant comorbidities, including smoking status. Logistic regression was used to compare medical and surgical outcomes. Trends and costs were generated for both groups as well.

RESULTS

ALIF/LLIF utilization in posterior long fusion has been steadily increasing since 2010, whereas PSO utilization has significantly dropped since 2017. PSO was associated with an increased risk of durotomy ( P < 0.001) and neurological injury ( P = 0.018). ALIF/LLIF was associated with increased rates of postoperative radiculopathy ( P = 0.005). Patients who underwent PSO had higher rates of pseudarthrosis within 1 and 2 years ( P = 0.015; P = 0.010), 1-year hardware failure ( P = 0.028), and 2-year reinsertion of instrumentation ( P = 0.009). Reoperation rates for both approaches were not statistically different at any time point throughout the 5-year period. In addition, there were no significant differences in both procedural and 90-day postoperative costs.

CONCLUSIONS

PSO was associated with higher rates of surgical complications compared with anterior approaches. However, there was no significant difference in overall reoperation rates. Spine surgeons should select the optimal technique for a given patient and the type of lordotic correction required.

Evaluation and Rehabilitation after Adult Lumbar Spine Surgery

Purpose: With an increase in the proportion of elderly patients, the global burden of spinal disease is on the rise. This is gradually expected to increase the number of surgical procedures all over the world in the near future. As we know, rehabilitation following spine surgery is critical for optimal recovery. However, the current literature lacks consensus regarding the appropriate post-operative rehabilitation protocol. The purpose of this review is to evaluate the optimal protocol for rehabilitation after lumbar spine surgery in adults. Materials and Methods: The goals of rehabilitation after lumbar spine surgery are to improve physical and psychosocial function and may include multiple modalities such as physical therapy, cognitive behavioral therapy, specialized instruments, and instructions to be followed during activities of daily living. In recent years, not only are a greater number of spine surgeries being performed, but various different techniques of lumbar spine surgery and spinal fusion have also emerged. (1) Our review summarizes post-operative rehabilitation under the following headings-1. Historical aspects, 2. Subjective functional outcomes, and (3) Actual rehabilitation measures, including balance. Results: Physical therapy programs need to be patient-specific and surgery-specific, such that they consider patient-reported outcome measures and take into consideration the technique of spinal fusion used and the muscle groups involved in these surgeries. By doing so, it is possible to assess the level of functional impairment and then specifically target the strengthening of those muscle groups affected by surgery whilst also improving impaired balance and allowing a return to daily activities. Conclusions: Rehabilitation is a multi-faceted journey to restore mobility, function, and quality of life. The current rehabilitation practice focuses on muscle strengthening, but the importance of spinal balance is less elaborated. We thus equally emphasize muscle strengthening and balance improvement post-lumbar spine surgery.

Moderate sagittal plane deformity patients have similar radiographic and functional outcomes with either anterior or posterior surgery

PURPOSE

This study aimed to compare the functional and radiographic outcomes of two surgical interventions for adult spinal deformity (ASD): anterior lumbar interbody fusion with anterior column realignment (ALIF-ACR) and posterior approach using Smith-Peterson osteotomy with transforaminal lumbar interbody fusion and pedicle screw fixation (TLIF-Schwab2).

METHODS

A retrospective cohort study included 61 ASD patients treated surgically between 2019 and 2020 at a single tertiary orthopedic specialty hospital. Patients were divided into two groups: Group 1 (ALIF-ACR, 29 patients) and Group 2 (TLIF-Schwab2, 32 patients). Spinopelvic radiographic parameters and functional outcomes were evaluated at 3, 6, and 12 months postsurgery.

RESULTS

Perioperative outcomes favored the ALIF-ACR group, with significantly smaller blood loss, shorter hospital stay, and operative time. Radiographic and functional outcomes were similar for both groups; however, the ALIF-ACR group did have a greater degree of correction in lumbar lordosis at 12 months. Complication profiles varied, with the ALIF-ACR group experiencing mostly hardware-related complications, while the TLIF-Schwab2 group faced dural tears, wound dehiscence, and proximal junctional kyphosis. Both groups had similar revision rates.

CONCLUSION

Both ALIF-ACR and TLIF-Schwab2 achieved similar radiographic and functional outcomes in ASD patients with moderate sagittal plane deformity at 1-year follow-up. However, the safety profiles of the two techniques differed. Further research is required to optimize patient selection for each surgical approach, aiming to minimize perioperative complications and reoperation rates in this challenging patient population.

Defining the Post-Operative Progression of Degenerative Scoliosis: An Analysis of Cases without Instrument Failure

OBJECTIVE

The expected post-operative changes in radiographic alignment over time remain poorly defined in patients surgically treated for degenerative scoliosis without instrument failure. Here we aim to describe the optimal natural progression of radiographic degenerative scoliosis at multiple timepoints in patients treated with a transforaminal lumbar interbody fusion (TLIF).

METHODS

We identified an initial retrospective cohort of 114 patients treated with a TLIF for degenerative scoliosis between 2018 and 2022, with 39 patients ultimately meeting the imaging inclusion criteria. Patients who completed a primary or revision procedure with no evidence of instrument failure, proximal junctional kyphosis, or proximal junctional failure at last follow-up were included. Radiographic measurements of spinopelvic alignment were manually extracted from X-Ray scoliosis films.

RESULTS

Thirty-nine patients (mean age 62.6 ± 8.7, mean follow-up 2.9 years), of which 23 underwent a primary TLIF (Primary) and 16 a revision procedure (Revision), were analyzed. Patients in the Primary group experienced a durable improvement in Thoracolumbar Cobb angle (-25° ± 15°), Thoracic Kyphosis (10° ± 13°), and Pelvic Incidence/lumbar lordosis mismatch (PI/LL) (-19° ± 19°) through the first year of follow-up. In the Revision group, at one year follow-up, all measures of spinopelvic alignment except PI/LL mismatch had reverted to pre-operative levels. Thoracolumbar Cobb angle decreased to a significantly greater degree in the Primary group compared to the Revision group.

CONCLUSION

Primary TLIF operations without instrument failure consistently improve radiographic outcomes in three key measures through the first year. For revision procedures, there appears to be modest radiographic benefit at follow-up.

Effectiveness of a two-stage posterior-anterior-posterior surgery using subcutaneously preserved autologous bone grafts for adult spinal deformity: a retrospective observational study

BACKGROUND

To achieve optimal correction of rigid kyphoscoliosis, we developed a novel two-stage posterior-anterior-posterior (PAP) surgery using subcutaneously preserved autologous bone grafts. This study aimed to investigate the effectiveness of two-stage PAP surgery versus single-stage anterior-posterior (AP) surgery.

METHODS

This was a retrospective analysis of patients undergoing combined anterior-posterior long-level fusion for adult spinal deformity (ASD) with a minimum 2-year follow-up. The indications for two-stage PAP surgery were rigid thoracolumbar deformity associated with hypertrophic facet arthritis and/or a large pelvic incidence-lumbar lordosis mismatch of > 25°. In the first stage of PAP surgery, pedicle screw insertion and multilevel Ponte osteotomies were performed. The resected local bone was embedded under sutured fascia. One week later, the embedded bone was retrieved in the right lateral position and used as an autograft for lateral lumbar interbody fusion. Final deformity correction was performed in the prone position.

RESULTS

From January 2018 to April 2021, 12 and 16 patients with ASD underwent two-stage PAP surgery (PAP group) and single-stage AP surgery (AP group), respectively. Although PAP surgery was associated with a significantly longer operation time, the total blood loss volume was significantly less in the PAP group than the AP group. Compared with the AP group, the PAP group showed significantly larger postoperative changes in radiological parameters in the sagittal and coronal planes. The overall complication rate did not differ significantly between the two groups.

CONCLUSION

Two-stage PAP surgery provided effective correction of rigid kyphoscoliosis without increasing blood loss and postoperative complication rates.

Combined Anterior-Posterior vs. Posterior-Only Approach in Adult Spinal Deformity Surgery: Which Strategy Is Superior?

Introduction: Whether a combined anterior-posterior (AP) approach offers additional benefits over the posterior-only (P) approach in adult spinal deformity (ASD) surgery remains unknown. In a cohort of patients undergoing ASD surgery, we compared the combined AP vs. the P-only approach in: (1) preoperative/perioperative variables, (2) radiographic measurements, and (3) postoperative outcomes. Methods: A single-institution, retrospective cohort study was performed for patients undergoing ASD surgery from 2009 to 2021. Inclusion criteria were ≥5-level fusion, sagittal/coronal deformity, and 2-year follow-up. The primary exposure was the operative approach: a combined AP approach or P alone. Postoperative outcomes included mechanical complications, reoperation, and minimal clinically important difference (MCID), defined as 30% of patient-reported outcome measures (PROMs). Multivariable linear regression was controlled for age, BMI, and previous fusion. Results: Among 238 patients undergoing ASD surgery, 34 (14.3%) patients underwent the AP approach and 204 (85.7%) underwent the P-only approach. The AP group consisted mostly of anterior lumbar interbody fusion (ALIF) at L5/S1 (73.5%) and/or L4/L5 (38.0%). Preoperatively, the AP group had more previous fusions (64.7% vs. 28.9%, p < 0.001), higher pelvic tilt (PT) (29.6 ± 11.6° vs. 24.6 ± 11.4°, p = 0.037), higher T1 pelvic angle (T1PA) (31.8 ± 12.7° vs. 24.0 ± 13.9°, p = 0.003), less L1-S1 lordosis (-14.7 ± 28.4° vs. -24.3 ± 33.4°, p < 0.039), less L4-S1 lordosis (-25.4 ± 14.7° vs. 31.6 ± 15.5°, p = 0.042), and higher sagittal vertical axis (SVA) (102.6 ± 51.9 vs. 66.4 ± 71.2 mm, p = 0.005). Perioperatively, the AP approach had longer operative time (553.9 ± 177.4 vs. 397.4 ± 129.0 min, p < 0.001), more interbodies placed (100% vs. 17.6%, p < 0.001), and longer length of stay (8.4 ± 10.7 vs. 7.0 ± 9.6 days, p = 0.026). Radiographically, the AP group had more improvement in T1PA (13.4 ± 8.7° vs. 9.5 ± 8.6°, p = 0.005), L1-S1 lordosis (-14.3 ± 25.6° vs. -3.2 ± 20.2°, p < 0.001), L4-S1 lordosis (-4.7 ± 16.4° vs. 3.2 ± 13.7°, p = 0.008), and SVA (65.3 ± 44.8 vs. 44.8 ± 47.7 mm, p = 0.007). These outcomes remained statistically significant in the multivariable analysis controlling for age, BMI, and previous fusion. Postoperatively, no significant differences were found in mechanical complications, reoperations, or MCID of PROMs. Conclusions: Preoperatively, patients undergoing the combined anterior-posterior approach had higher PT, T1PA, and SVA and lower L1-S1 and L4-S1 lordosis than the posterior-only approach. Despite increased operative time and length of stay, the anterior-posterior approach provided greater sagittal correction without any difference in mechanical complications or PROMs.

Clinical and Radiologic Analysis of Minimally Invasive Anterior-Posterior Combined Surgery for Adult Spinal Deformity: Comparison of Oblique Lateral Interbody Fusion at L5/S1 (OLIF51) versus Transforaminal Interbody Fusion

Background and Objectives: Although adult spinal deformity (ASD) surgery brought about improvement in the quality of life of patients, it is accompanied by high invasiveness and several complications. Specifically, mechanical complications of rod fracture, instrumentation failures, and pseudarthrosis are still unsolved issues. To better improve these problems, oblique lateral interbody fusion at L5/S1 (OLIF51) was introduced in 2015 at my institution. The objective of this study was to compare the clinical and radiologic outcomes of anterior-posterior combined surgery for ASD between the use of OLIF51 and transforaminal interbody fusion (TLIF) at L5/S1. Materials and Methods: A total of 117 ASD patients received anterior-posterior correction surgeries either with the use of OLIF51 (35 patients) or L5/S1 TLIF (82 patients). In both groups, L1-5 OLIF and minimally invasive posterior procedures of hybrid or circumferential MIS were employed. The sagittal and coronal spinal alignment and spino-pelvic parameters were recorded preoperatively and at follow-up. The quality-of-life parameters and visual analogue scale were evaluated, as well as surgical complications at follow-up. Results: The average follow-up period was thirty months (13-84). The number of average fused segments was eight (4-12). The operation time and estimated blood loss were significantly lower in OLIF51 than in TLIF. The PI-LL mismatch, LLL, L5/S1 segmental lordosis, and L5 coronal tilt were significantly better in OLIF51 than TLIF. The complication rate was statistically equivalent between the two groups. Conclusions: The introduction of OLIF51 for adult spine deformity surgery led to a decrease in operation time and estimated blood loss, as well as improvement in sagittal and coronal correction compared to TLIF. The circumferential MIS correction and fusion with OLIF51 serve as an effective surgical modality which can be applied to many cases of adult spinal deformity.

Can Pelvic Incidence Change After Lumbo-Pelvic Fixation for Adult Spine Deformity, and Would the Change be Affected by the Type of Pelvic Fixation?

STUDY DESIGN

Retrospective review.

OBJECTIVE

To assess the change in pelvic incidence (PI) after lumbo-pelvic fixation and the differential impact of the type of pelvic fixation: S2-alar-iliac screws (S2AI) versus Iliac screws (IS) on postoperative PI.

SUMMARY OF BACKGROUND DATA

Recent studies suggest that changes occur to the previously assumed fixed PI after spino-pelvic fixation.

METHODS

Adult spine deformity (ASD) patients who underwent spino-pelvic fixation with≥4 levels of fusion were included. Preoperative and postoperative PI, lumbar lordosis (LL), thoracic kyphosis, pelvic tilt, sacral slope, PI-LL mismatch, and the Sagittal Vertical Axis (SVA) were analyzed on EOS imaging. A significant PI change was established at≥6°. Patients were categorized based on the type of pelvic fixation (S2AI vs. IS).

RESULTS

One-hundred-forty-nine patients were included. Of these, 77(52%) had a>6° change in their PI postoperatively. In patients with high preoperative PI (>60°), 62% had a significant PI change compared with 33% of patients with normal PI (40°-60°) and 53% in patients with low PI (<40°; P =0.01). PI was likely to decrease in patients with high baseline PI (>60°) and to increase in patients with low baseline PI (<40°). Patients with a significant PI change had a higher PI-LL. Patients in the S2AI group (n=99) and those in the IS group (n=50) were comparable at baseline. In the S2AI group, 50 (51%) patients had>6° change in their PI compared with 27(54%) patients in the IS group( P =0.65). In both groups, patients with high preoperative PI were more prone to significant postoperative changes ( P =0.02 in IS, P =0.01 in S2AI).

CONCLUSION

PI changed significantly in 50% of patients postoperatively, especially in those with high/low preoperative PI and those with severe baseline sagittal imbalance. This occurs similarly in patients with S2AI and those with IS screws. Surgeons should keep in mind these anticipated changes while planning ideal LL, as this impacts postoperative PI-LL mismatch.

LEVEL OF EVIDENCE

4.

The use of lateral lumbar interbody fusion for identifying adult patients with spinal deformities treatable by short corrective fusion in 2-stage surgery

BACKGROUND

To investigate and compare the surgical outcomes of short and thoracopelvic corrective fusion with our two-stage technique using lateral lumbar interbody fusion (LLIF) and posterior open surgery.

METHODS

Consecutive patients with adult spinal deformities who underwent a planned two-stage anterior-posterior surgery, using LLIF for the first stage and posterior open corrective fusion for the second stage, with a minimum of 2 years of follow-up were included. Patients who underwent lumbar or lumbosacral corrective fusion and thoracopelvic corrective fusion were categorized into the short group and thoracopelvic groups, respectively. We investigated the spinopelvic parameters and patient-reported outcome measurements.

RESULTS

Seventy-four consecutive patients (8 men, 66 women; average age, 70.0 years) were included. Ten patients underwent short corrective fusion following significant improvements in the symptoms and radiographic parameters post-LLIF. Several preoperative spinopelvic parameters were better in the short group. Compared to the thoracopelvic group, those who underwent short fusion had a poorer alignment 2 years postoperatively but with comparable results and a significantly higher function score on the Scoliosis Research Society-22 r (SRS-22r) questionnaire. The mean Oswestry Disability Index and SRS-22r scores significantly improved during the 2-year postoperative follow-up in both the groups.

CONCLUSIONS

Short corrective fusion can be considered in patients whose symptoms and radiographic parameters significantly improve following LLIF. Patients who undergo short fusion with LLIF application have poorer alignment than those who undergo thoracopelvic fusion 2 years postoperatively; however, the results are comparable, and the function score is significantly improved.

Modified posterior osteotomy for osteoporotic vertebral collapse with neurological dysfunction in thoracolumbar spine: a preliminary study

OBJECTIVE

The risk of osteoporotic vertebral collapse (OVC) associated with delayed neurological dysfunction (DND) is substantial, and performing surgery for this condition in elderly patients presents challenges. The focus of the current research is on simplifying surgical procedures while maintaining their effectiveness. This study was designed to contribute clinical data supporting the use of modified posterior osteotomy for treating thoracolumbar OVC with DND. The study compares perioperative clinical parameters, imaging data characteristics, and changes in efficacy outcome indicators to provide evidence for the advancement of this technique.

METHODS

A total of 12 patients diagnosed with osteoporotic vertebral collapse and neurological dysfunction were included in the study. All patients underwent modified posterior osteotomy. Data regarding perioperative and radiological parameters as well as complications such as surgery duration, blood loss, ASIA grade, VAS, ODI, regional kyphosis angle (RKA), anterior vertebral height ratio (AVHr), and spinal canal clearance ratio (SCCr), were collected retrospectively. These parameters were then analysed to evaluate the clinical efficacy and safety of the modified posterior osteotomy technique.

RESULTS

A total of 12 patients were included in the study, with a mean age of 65.5 ± 9.7 years. The average follow-up period was 29.4 ± 5.0 months. The mean operative blood loss was 483.3 ± 142.0 ml, and the average operative time was 3.7 ± 0.7 h. The visual analogue scale (VAS) score decreased from a preoperative value of 5.8 ± 0.7 to a final follow-up value of 1.3 ± 0.8 (P < 0.05), indicating a significant improvement in pain. The ODI decreased from 65.2 ± 6.0 before surgery to 20.5 ± 7.0, indicating a decrease in disability, and the postoperative neurological function showed a significant improvement. Correction of the RKA was observed, with the angle changing from 35.8 ± 10.8° before surgery to 20.0 ± 3.5° after surgery and to 22.5 ± 3.1° at the final follow-up. Similarly, correction of the AVHr was observed, with the height changing from 39.3 ± 18.0 to 63.0 ± 14.3 after surgery and to 53.9 ± 8.9 at the final follow-up. Correction of the SCCr was also observed, with the ratio changing from 54.9 ± 5.4 to 68.1 ± 5.3 after surgery and to 68.68 ± 6.76 at the final follow-up.

CONCLUSIONS

Posterior modified osteotomy is an effective treatment for thoracolumbar osteoporotic fractures with OVC combined with DND. It can significantly preserve vertebral height, increase vertebral canal volume, correct kyphotic angle, and improve postoperative neurological function. The simplified osteotomy also offers advantages in terms of operating time, blood loss, postoperative VAS score, and improvement in lumbar function.

Incidence of Surgical Site Infection Following Lateral Lumbar Interbody Fusion Compared With Posterior/Transforaminal Lumbar Interbody Fusion: A Propensity Score-Weighted Study

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The objective of this study was to compare the incidence of surgical site infection (SSI) after lateral lumbar interbody fusion (LLIF) and posterior/transforaminal lumbar interbody fusion ( P /TLIF).

SUMMARY OF BACKGROUND DATA

Previous studies have shown that LLIF can improve neurological symptoms to a comparable degree to P /TLIF. However, data on the risk of SSI after LLIF is lacking compared with P /TLIF.

MATERIALS AND METHODS

The study was conducted under a retrospective cohort design in patients undergoing LLIF or P /TLIF for lumbar degenerative diseases between 2013 and 2020 using a hospital administrative database. We used propensity score overlap weighting to adjust for confounding factors including age, sex, body mass index, comorbidities, number of fusion levels, hospital size, and surgery year. We estimated weighted odds ratios (ORs) and 95% CIs for SSI within 30 days postoperatively.

RESULTS

We compared the risk of SSI between 2874 patients who underwent LLIF and 24,245 patients who received P/TLIF Patients who had received LLIF were at significantly less risk of experiencing an SSI compared with those receiving P/TLIF (0.7% vs. 1.2%; weighted OR: 0.57; 95% CI: 0.36 -0.92; P=0.02). As a secondary outcome, patients who had received LLIF had less risk of transfusion (7.8% vs. 11.8%; weighted OR: 0.63; 95% CI:0.54 -0.73; P <0.001).

CONCLUSIONS

In this large retrospective cohort study of adults undergoing lumbar interbody fusion, LLIF was associated with a significantly lower risk of SSI than P /TLIF. The small, but significantly, decreased risk of SSI associated with LLIF may inform decisions regarding the technical approach for lumbar interbody fusion.

Biomechanical Comparison of Multilevel Stand-Alone Lumbar Lateral Interbody Fusion With Posterior Pedicle Screws: An In Vitro Study

OBJECTIVE

Lumbar lateral interbody fusion (LLIF) allows placement of large interbody cages while preserving ligamentous structures important for stability. Multiple clinical and biomechanical studies have demonstrated the feasibility of stand-alone LLIF in single-level fusion. We sought to compare the stability of 4-level stand-alone LLIF utilizing wide (26 mm) cages with bilateral pedicle screw and rod fixation.

METHODS

Eight human cadaveric specimens of L1-5 were included. Specimens were attached to a universal testing machine (MTS 30/G). Flexion, extension, and lateral bending were attained by applying a 200 N load at a rate of 2 mm/sec. Axial rotation of ± 8° of the specimen was performed at 2°/sec. Three-dimensional specimen motion was recorded using an optical motion-tracking device. Specimens were tested in 4 conditions: (1) intact, (2) bilateral pedicle screws and rods, (3) 26-mm stand-alone LLIF, (4) 26-mm LLIF with bilateral pedicle screws and rods.

RESULTS

Compared to the stand-alone LLIF, bilateral pedicle screws and rods had 47% less range of motion in flexion-extension (p < 0.001), 21% less in lateral bending (p < 0.05), and 20% less in axial rotation (p = 0.1). The addition of bilateral posterior instrumentation to the stand-alone LLIF resulted in decreases of all 3 planes of motion: 61% in flexion-extension ( p < 0.001), 57% in lateral bending (p < 0.001), 22% in axial rotation (p = 0.002).

CONCLUSION

Despite the biomechanical advantages associated with the lateral approach and 26 mm wide cages, stand-alone LLIF for 4-level fusion is not equivalent to pedicle screws and rods.

Comparison of staged LLIF combined with posterior instrumented fusion with posterior instrumented fusion alone for the treatment of adult degenerative lumbar scoliosis with sagittal imbalance

BACKGROUND

To retrospectively compare the clinical and radiological outcomes of staged lateral lumbar interbody fusion (LLIF) combined with posterior instrumented fusion(PIF)with PIF alone for the treatment of adult degenerative lumbar scoliosis (ADLS) with sagittal imbalance.

METHODS

ADLS patients with sagittal imbalance underwent corrective surgery were included and divided into staged group (underwent multilevel LLIF in the first-stage and PIF in the second-stage) and control group (PIF alone). The clinical and radiological outcomes were evaluated and compared between the two groups.

RESULTS

Forty-five patients with an average age of 69.7±6.3 years were enrolled, including 25 in the staged group and 20 in the control group. Compared with preoperative values, patients in both groups achieved significant improvement in terms of ODI, VAS back, VAS leg and spinopelvic parameters after surgery, which were maintained well during the follow-up period. Compared with control group, total operative time in the staged group was longer, but the amounts of blood loss and blood transfusion were reduced. The average posterior fixation segments were 6.20±1.78 in the staged group and 8.25±1.16 in the control group (P<0.01), respectively. Posterior column osteotomy (PCO) was performed in 9 patients (36%) in the staged group, while PCO and/or pedicle subtraction osteotomy were performed in 15 patients (75%) in the control group (P<0.01). There was no difference in complications between the two groups.

CONCLUSION

Both surgical strategies were effective for the treatment of ADLS with sagittal imbalance. However, staged treatment was less invasive, which reduced the number of posterior fixation segments and osteotomy requirement.

What Are the Benefits of Lateral Lumbar Interbody Fusion on the Treatment of Adult Spinal Deformity: A Systematic Review and Meta-Analysis Deformity

STUDY DESIGN

A systematic review and meta-analysis.

OBJECTIVE

The purpose of this systematic review and meta-analysis was to compare the efficacy of lateral lumbar interbody fusion (LLIF) combined with posterior spinal fusion (PSF) with that of conventional PSF in the treatment of adult spinal deformity (ASD).

METHODS

A comprehensive literature search was performed for relevant studies in PubMed, EMBASE, Web of Science, and the Cochrane Library. Spinopelvic parameters, surgical data, complications, and clinical outcomes at the last follow-up were compared between patients with ASD who underwent LLIF combined with PSF (LLIF+PSF group) and those who underwent conventional PSF (only-PSF group).

RESULTS

Ten studies, comprising 621 patients with ASD (313 in the LLIF+PSF group and 308 in the only-PSF group), were included. The level of evidence was III for 7 studies and IV for 3 studies. There was no significant difference in the improvement in the visual analog scale score, systemic complication rate, and revision rate between groups. In the LLIF+PSF group, we noted a superior restoration of lumbar lordosis (weighted mean difference [WMD], 9.77; 95% confidence interval [CI] 7.10 to 12.44, P < .001), pelvic tilt (WMD, -2.50; 95% CI -4.25 to -.75, P = .005), sagittal vertical axis (WMD, -21.92; 95% CI -30.73 to -13.11, P < .001), and C7 plumb line-center sacral vertical line (WMD, -4.03; 95% CI -7.52 to -.54, P = .024); a lower estimated blood loss (WMD, -719.99; 95% CI -1105.02 to -334.96, P < .001) while a prolonged operating time (WMD, 104.89; 95% CI 49.36 to 160.43, P < .001); lower incidence of pseudarthrosis (risk ratio [RR], .26; 95% CI .08 to .79, P = .017) while higher incidence of neurologic deficits (RR, 2.04; 95% CI 1.27 to 3.25, P = .003); and a better improvement in Oswestry Disability Index score (WMD, -7.04; 95% CI -10.155 to -3.93, P < .001) and Scoliosis Research Society-22 total score (WMD, .27; 95% CI .11 to .42, P = .001). The level of evidence in this systematic review and meta-analysis was II.

CONCLUSION

Compared with conventional PSF, LLIF combined with PSF was associated with superior restoration of sagittal and coronal alignment, lower incidence of pseudarthrosis, better improvement in quality of life, and less surgical invasiveness in the treatment of ASD, albeit at the cost of prolonged surgical times and substantially high incidence of lower extremity symptoms. Surgeons should weigh the advantages and disadvantages of this procedure, and inform patients about its side effects.

A Short-Term Assessment of Lumbar Sagittal Alignment Parameters in Patients Undergoing Anterior Lumbar Interbody Fusion

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To determine if intraoperative on-table lumbar lordosis (LL) and segmental lordosis (SL) coincide with perioperative change in lordosis.

SUMMARY OF BACKGROUND DATA

Improvements in sagittal alignment are believed to correlate with improvements in clinical outcomes. Thus, it is important to establish whether intraoperative radiographs predict postoperative improvements in LL or SL.

MATERIALS AND METHODS

Electronic medical records were reviewed for patients ≥18 years old who underwent single-level and two-level anterior lumbar interbody fusion with posterior instrumentation between 2016 and 2020. LL, SL, and the lordosis distribution index were compared between preoperative, intraoperative, and postoperative radiographs using paired t tests. A linear regression determined the effect of subsidence on SL and LL.

RESULTS

A total of 118 patients met inclusion criteria. Of those, 75 patients had one-level fusions and 43 had a two-level fusion. LL significantly increased following on-table positioning [delta (Δ): 5.7°, P <0.001]. However, LL significantly decreased between the intraoperative to postoperative radiographs at two to six weeks (Δ: -3.4°, P =0.001), while no change was identified between the intraoperative and more than three-month postoperative radiographs (Δ: -1.6°, P =0.143). SL was found to significantly increase from the preoperative to intraoperative radiographs (Δ: 10.9°, P <0.001), but it subsequently decreased at the two to six weeks follow up (Δ: -2.7, P <0.001) and at the final follow up (Δ: -4.1, P <0.001). On linear regression, cage subsidence/allograft resorption was predictive of the Δ SL (β=0.55; 95% confidence interval: 0.16-0.94; P =0.006), but not LL (β=0.10; 95% confidence interval: -0.44 to 0.65; P =0.708).

CONCLUSION

Early postoperative radiographs may not accurately reflect the improvement in LL seen on intraoperative radiographic imaging, but they are predictive of long-term lumbar sagittal alignment. Each millimeter of cage subsidence or allograft resorption reduces SL by 0.55°, but subsidence does not significantly affect LL.

LEVELS OF EVIDENCE

4.

Surgical sequence in anterior column realignment with posterior osteotomy is important for degree of adult spinal deformity correction: advantages and indications for posterior to anterior sequence

BACKGROUND

We hypothesized that posterior osteotomy prior to ACR (Anterior column realignment) through P-A-P surgical sequence would permit a greater correction for deformity corrective surgery than the traditional A-P sequence without posterior osteotomy. This study aimed to determine the impact of the P-A-P sequence on the restoration of lumbar lordosis (LL) compared to the A-P sequence in deformity corrective surgery for adult spinal deformity (ASD) patients and to identify the characteristics of patients who require this sequence.  METHODS: Between 2017 and 2019, 260 ASD patients who had undergone combined corrective surgery were reviewed retrospectively. This study included 178 patients who underwent posterior osteotomy before the ACR (P-A group) and 82 patients who underwent the A-P sequence (A-P group). Sagittal spinopelvic parameters were determined from pre- and postoperative whole-spine radiographs and compared between the groups. To find better indications for the P-A-P sequence, we conducted additional analysis on postoperative outcomes of patients in the A-P group.  RESULTS: The P-A group showed a significantly higher change in LL (53.7° vs. 44.3°, p < 0.001), C7 sagittal vertical axis (C7 SVA: 197.4 mm vs. 146.1 mm, p = 0.021), segmental lordosis (SL) L2/3 (16.2° vs. 14.4°, p = 0.043), SL L3/4 (16.2° vs. 13.8°, p = 0.004), and SL L4/5 (15.1° vs. 11.3°, p = 0.001) compared to the A-P group. At the final follow-up, pelvic incidence (PI) minus LL mismatch (PI - LL mismatch) was significantly higher in the A-P group (13.4° vs. 2.9°, p < 0.001). Stepwise logistic regression analysis showed that age ≥ 75 years (odds ratio [OR] = 2.151; 95% confidence interval [CI], 1.414-3.272; p < 0.001), severe osteoporosis (OR = 2.824; 95% CI, 1.481-5.381; p = 0.002), rigid lumbar curve with dynamic changes in LL < 10° (OR = 5.150; 95% CI, 2.296-11.548; p < 0.001), and severe facet joint osteoarthritis (OR = 4.513; 95% CI, 1.958-10.402; p < 0.001) were independent risk factors for PI - LL mismatch ≥ 10° after A-P surgery.

CONCLUSION

P-A-P sequence for deformity corrective surgery in ASD offers greater LL correction than the A-P sequence. Indications for the procedure include patients aged ≥ 75 years, severe osteoporosis, rigid lumbar curve with dynamic change in LL < 10°, or more than four facet joints of Pathria grade 3 in the lumbar region.

Patient-reported outcome measures in spine surgery: A systematic review

Background

Steadily increasing expenditure in the United States health-care system has led to a shift toward a value-based model that focuses on quality of care and cost-effectiveness. Operations involving the spine rank among some of the most common and expensive procedures performed in operating rooms nationwide. Patient-reported outcomes measures (PROMs) are a useful tool for reporting levels of outcome and analyzing patient recovery but are both under-utilized and nonstandardized in spine surgery.

Methods

We conducted a systematic review of the literature using the PubMed database, focusing on the most commonly utilized PROMs for spine disease as well as spinal deformity. The benefits and drawbacks of these PROMs were then summarized and compared.

Results

Spine-specific PROMs were based on the class of disease. The most frequently utilized PROMs were the Neck Disability Index and the modified Japanese Orthopaedic Association scale; the Oswestry Disability Index and the Roland-Morris Disability Questionnaire; and the Scoliosis Research Society 22-item questionnaire (SRS-22) for cervicothoracic spine disease, lumbar spine disease, and spinal deformity, respectively.

Conclusion

We found limited, though effective, use of PROMs targeting specific classes of disease within spine surgery. Therefore, we advocate for increased use of PROMs in spine surgery, in both the research and clinical settings. PROM usage can help physicians assess subjective outcomes in standard ways that can be compared across patients and institutions, more uniquely tailor treatment to individual patients, and engage patients in their own medical care.

Application of Offset Dingo Instruments in Anterior to Psoas (ATP)/Oblique Lumbar Interbody Fusion (OLIF) Procedure: A Retrospective Study of 80 Patients

OBJECTIVE

Oblique lumbar interbody fusion (OLIF) is a minimally invasive lumbar fusion procedure that has flourished in recent years. However, complications related to the anterior-to-psoas (ATP) approach have been reported. The purpose of this study was to assess the OLIF technique using offset design "Dingo" instruments for the treatment of degenerative lumbar disorders.

METHODS

A retrospective review was performed to identify patients between March 2018 and November 2020 who underwent OLIF with conventional or modified instruments with a minimum follow-up of 12 months. Demographic data were recorded. Operation time, intraoperative blood loss, and length of hospital stay were compared between cohorts. Imaging parameters were measured and compared between cohorts before and after surgery. Clinical outcomes were assessed at each follow-up visit. All complications were reviewed.

RESULTS

A total of 80 consecutive patients were included. The mean follow-up times for the conventional group and modified group were 14.5 months and 16.3 months, respectively. The incidence of hip flexion weakness was 27.5% and 7.5% for the conventional cohort and modified cohort, respectively. The modified group was associated with a shorter operation time, shorter length of hospital stay, higher postoperative disk height and better cage position. The symptoms of all patients improved after surgery. At 1-week follow-up, the modified group showed significantly better clinical scores.

CONCLUSIONS

OLIF with modified instruments and techniques shows promising outcomes in reducing approach-related complications. Additionally, the modified technique is associated with a better cage position, shorter length of hospital stay and less postoperative pain in the early period.

Combined anterior-posterior versus all-posterior approaches for adult spinal deformity correction: a matched control study

PURPOSE

Anterior approaches are gaining popularity for adult spinal deformity (ASD) surgeries especially with the introduction of hyperlordotic cages and improvement in MIS techniques. Combined Approaches provide powerful segmental sagittal correction potential and increase the surface area available for fusion in ASD surgery, both of which would improve overall. This is the first study directly comparing surgical outcomes between combined anterior-posterior approaches and all-posterior approach in a matched ASD population.

METHODS

This is a retrospective matched control cohort analysis with substitution using a multicenter prospectively collected ASD data of patients with > 2 year FU. Matching criteria include: age, American Society of Anesthesiologists Score, Lumbar Cobb angle, sagittal deformity (Global tilt) and ODI.

RESULTS

In total, 1024 ASD patients were available for analysis. 29 Combined Approaches patients met inclusion criteria, and only 22 could be matched (1:2 ratio). Preoperative non-matched demographical, clinical, surgical and radiological parameters were comparable between both groups. Combined approaches had longer surgeries (548 mns vs 283) with more blood loss (2850 ml vs 1471) and needed longer ICU stays (74 h vs 27). Despite added morbidity, they had comparable complication rates but with significantly less readmissions (9.1% vs 38.1%) and reoperations (18.2% vs 43.2%) at 2 years. Combined Approaches achieved more individualised and harmonious deformity correction initially. At the 2 years control, Combined Approaches patients reported better outcomes as measured by COMI and SRS scores. This trend was maintained at 3 years.

CONCLUSION

Despite an increased initial surgical invasiveness, combined approaches seem to achieve more harmonious correction with superior sagittal deformity control; they need fewer revisions and have improved long-term functional outcomes when compared to all-posterior approaches for ASD deformity correction.

Adult Spinal Deformity Surgery Is Associated with Increased Productivity and Decreased Absenteeism From Work and School

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

We hypothesized that adult spinal deformity (ASD) surgery would be associated with improved work- and school-related productivity, as well as decreased rates of absenteeism.

SUMMARY OF BACKGROUND DATA

ASD patients experience markedly decreased health-related quality of life along many dimensions.

METHODS

Only patients eligible for 2-year follow-up were included, and those with a history of previous spinal fusion were excluded. The primary outcome measures in this study were Scoliosis Research Society-22r score (SRS-22r) questions 9 and 17. A repeated measures mixed linear regression was used to analyze responses over time among patients managed operatively (OP) versus nonoperatively (NON-OP).

RESULTS

In total, 1188 patients were analyzed. 66.6% were managed operatively. At baseline, the mean percentage of activity at work/school was 56.4% (standard deviation [SD] 35.4%), and the mean days off from work/school over the past 90 days was 1.6 (SD 1.8). Patients undergoing ASD surgery exhibited an 18.1% absolute increase in work/school productivity at 2-year follow-up versus baseline (P < 0.0001), while no significant change was observed for the nonoperative cohort (P > 0.5). Similarly, the OP cohort experienced 1.1 fewer absent days over the past 90 days at 2 years versus baseline (P < 0.0001), while the NON-OP cohort showed no such difference (P > 0.3). These differences were largely preserved after stratifying by baseline employment status, age group, sagittal vertical axis (SVA), pelvic incidence minus lumbar lordosis (PI-LL), and deformity curve type.

CONCLUSION

ASD patients managed operatively exhibited an average increase in work/school productivity of 18.1% and decreased absenteeism of 1.1 per 90 days at 2-year follow-up, while patients managed nonoperatively did not exhibit change from baseline. Given the age distribution of patients in this study, these findings should be interpreted as pertaining primarily to obligations at work or within the home. Further study of the direct and indirect economic benefits of ASD surgery to patients is warranted.Level of Evidence: 3.

Complications of adult spinal deformity surgery: A literature review

Purpose:

Adult spinal deformity incidence increases accordingly as the population ages. Even though surgery is the best option for the treatment, the complications due to surgery are pretty challenging. This study aims to review the complication rates of adult spinal deformity surgery.

Methods:

A literature review of the last decade was performed searching for the query “Adult spine deformity and complication.” This search yielded 2781 results, where 79 articles were chosen to investigate the complications of adult spinal deformity surgery. In addition, the demographic data, surgical interventions, and complications were extracted from the publications.

Results:

A total of 26,207 patients were analyzed, and 9138 complications were found (34.5%). Implant failure, including screw loosening, breakage, distal and proximal junctional kyphosis, were the most common complications. The neurologic complications were about 10.8%, and the infection rate was 3.6%. Cardiac and pulmonary complications were about 4.8%.

Discussion:

Age, body mass index, smoking, osteoporosis, and other comorbidities are the significant risk factors affecting adult spinal deformity surgery. Presurgical planning and preoperative risk factor assessment must be done to avoid complications. Furthermore, intra and postoperative complications affect the patients’ quality of life and length of stay, and hospital readmissions. Revision surgery also increases the risk of complications.

Conclusion:

Good patient evaluation before surgery and careful planning of the surgery are essential in avoiding complications of adult spinal deformity.

Comparison of Lateral Lumbar Interbody Fusion and Posterior Lumbar Interbody Fusion as Corrective Surgery for Patients with Adult Spinal Deformity-A Propensity Score Matching Analysis

Lateral lumbar interbody fusion (LLIF) is increasingly performed as corrective surgery for patients with adult spinal deformity (ASD). This paper compares the surgical results of LLIF and conventional posterior lumbar interbody fusion (PLIF)/transforaminal lumbar interbody fusion (TLIF) in ASD using a propensity score matching analysis. We retrospectively reviewed patients with ASD who received LLIF and PLIF/TLIF, and investigated patients’ backgrounds, radiographic parameters, and complications. The propensity scores were calculated from patients’ characteristics, including radiographic parameters and preoperative comorbidities, and one–to-one matching was performed. Propensity score matching produced 21 matched pairs of patients who underwent LLIF and PLIF/TLIF. All radiographic parameters significantly improved in both groups at the final follow-up compared with those of the preoperative period. The comparison between both groups demonstrated no significant difference in terms of postoperative pelvic tilt, lumbar lordosis (LL), or pelvic incidence–LL at the final follow-up. However, the sagittal vertical axis tended to be smaller in the LLIF at the final follow-up. Overall, perioperative and late complications were comparable in both procedures. However, LLIF procedures demonstrated significantly less intraoperative blood loss and a smaller incidence of postoperative epidural hematoma compared with PLIF/TLIF procedures in patients with ASD.

Association of Sagittal Spinopelvic Realignment with Correction in Lower Lumbar Lordosis after Surgical Treatment in Degenerative Lumbar Scoliosis

Objective

To assess the effect that correction of lower lumbar lordosis (3L) has on global spine realignment due to the key role of 3L for scoliosis surgery in patients with degenerative lumbar scoliosis (DLS).

Methods

This study is a retrospective review performed between June 2018 and January 2020, including consecutive patients with DLS. Only patients age ≥ 45 years who had already undergone a selective root block operation and had the procedure of long‐fusion extending to pelvis and posterior lumbar interbody fusion (PLIF) at lower lumbar spine (L₄‐S₁) were retained for analysis. Spinopelvic parameters measured included thoracic kyphosis (TK), lumbar lordosis (LL), 3L, pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), T₁ pelvic angle (TPA), and sagittal vertical axis (SVA) at pre‐operation and the third month follow‐up. The mismatch (PI‐LL) was calculated subsequently. Pearson correlation and linear regression analysis were performed to explore the association of the changes in global spinopelvic parameters with 3L correction.

Results

Thirty‐nine patients (five males, 34 females) with the average age of 63.84 years (SD 7.53; range, 45–75 years) at the time of surgery were identified. All patients had the surgical procedure of long‐fusion (≥4 vertebras) with PLIF at lower lumbar spine between L₄ and S₁ spine. Lower instrumented vertebras (LIV) fused to pelvis (S₁, 14; S₂, 18; ilium, 7) were operated in all patients. Seventeen patients were with upper instrumented vertebras (UIV) at thoracolumbar spine (L₂‐T₁₁), and 22 patients at thoracic spine (T10 and above). The median of instrumented segments was 10 (5–14). 3L significantly increased (P = 0.02) after surgical treatment by mean change of 4.21° (range, −19.7° to +22.2°). Perioperatively, all spinopelvic parameters regarding to TK, LL, SS, PT, TPA, SVA, and mismatch (PI‐LL) had significant changes (P < 0.001). The change in 3L correlated significantly with the changes in spinopelvic parameters (r = 0.772 for LL, −0.589 for SVA, −0.439 for TPA, and −0.428 for PI‐LL). After linear regression analysis, the formulas were obtained: d‐LL = 14.977 + 0.636 × d‐3L, (R² = 0.596); d‐(PI‐LL) = 16.575 + 0.62 × d‐3L, (R² = 0.183); d‐TPA = −7.284 to 0.358 × d‐3L, (R² = 0.193); d‐SVA = −30.556–2.639 × d‐3L (R² = 0.347).

Conclusions

Correction in lower lumbar lordosis, following the surgical procedure of long‐fusion with PLIF at lower lumbar spine, could result in significant changes in full‐spine parameters. The significant association of changes in each of global spine parameter with the correction of 3L perioperatively could provide important information for surgeons to make a surgical plan for spinal correction.

Efficacy and radiographic analysis of oblique lumbar interbody fusion in treating adult spinal deformity

Adult spinal deformity (ASD) is usually rigid and requires a combined anterior–posterior approach for deformity correction. Anterior lumbar interbody fusion (ALIF) allows direct access to the disc space and placement of a large interbody graft. A larger interbody graft facilitates correction of ASD. However, an anterior approach carries significant risks. Lateral lumbar interbody fusion (LLIF) through a minimally invasive approach has recently been used for ASD. The present study was performed to evaluate the effectiveness of oblique lumbar interbody fusion (OLIF) in the treatment of ASD. We performed a retrospective study utilizing the data of 74 patients with ASD. The inclusion criteria were lumbar coronal Cobb angle > 20°, pelvic incidence (PI)–lumbar lordosis (LL) mismatch > 10°, and minimum follow–up of 2 years. Patients were divided into two groups: ALIF combined with posterior spinal fixation (ALIF+PSF) (n = 38) and OLIF combined with posterior spinal fixation (OLIF+PSF) (n = 36). The perioperative spinal deformity radiographic parameters, complications, and health-related quality of life (HRQoL) outcomes were assessed and compared between the two groups. The preoperative sagittal vertical axis (SVA), LL, PI–LL mismatch, and lumbar Cobb angles were similar between the two groups. Patients in the OLIF+PSF group had a slightly higher mean number of interbody fusion levels than those in the ALIF+PSF group. At the final follow–up, all radiographic parameters and HRQoL scores were similar between the two groups. However, the rates of perioperative complications were higher in the ALIF+PSF than OLIF+PSF group. The ALIF+PSF and OLIF+PSF groups showed similar radiographic and HRQoL outcomes. These observations suggest that OLIF is a safe and reliable surgical treatment option for ASD.

Improvement of coronal alignment in fractional low lumbar curves with the use of anterior interbody devices

STUDY DESIGN

Retrospective chart review.

OBJECTIVES

To determine if the addition of an anterior lumbar interbody fusion (ALIF) improves the fractional curve in adult spinal deformity correction when compared to posterior surgery alone. ALIF is commonly advocated to improve lordosis and fusion in adult deformity surgery. Improved fractional curve correction may help level the pelvis and minimize proximal malalignment.

METHODS

Patients undergoing thoracolumbar fusion to the pelvis with S2AI screws for deformity were identified and stratified into patients who had an ALIF as part of their deformity correction procedure (ALIF + PSF), and those who had a posterior approach alone. The posterior approach (PSF) includes patients who had a posterolateral fusion with or without a transforaminal lumbar interbody fusion (TLIF). Radiographic parameters measured included pre-op and post-op fractional coronal curve Cobb angle, lumbar lordosis, pelvic tilt, pelvic incidence and sacral slope, major Cobb angle, coronal and sagittal SVA.

RESULTS

There were 31 cases in the ALIF + PSF group and 28 in the PSF group. Baseline demographic characteristics of the two groups were similar. Mean pre-op fractional coronal Cobb (18.3° vs 13.4°, p = 0.027) was larger in the ALIF + PSF group, whereas lumbar lordosis (31.0° vs 33.6°, p = 0.487) and pelvic parameters were similar between the two groups. Post-op lumbar lordosis was similar (48.2° vs 43.0°, p = 0.092). Greater fractional coronal curve correction was achieved in the ALIF + PSF group (67%) compared to the PSF group (36%) with a smaller post-op fractional coronal curve in the ALIF + PSF group (6.1°) compared to the PSF group (8.6°, p = 0.053).

CONCLUSION

There is a greater correction of the fractional curve in the ALIF + PSF group compared with the PSF group. While this may not be the primary indication for ALIF, it is a benefit which may facilitate overall deformity correction and leveling of the pelvis.

Does Interbody Support at L5-S1 Matter in Long Fusions to the Pelvis?: A 5-year Analysis

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

To determine if the addition of L5-S1 interbody support in long fusion deformity constructs is associated with superior long-term clinical and radiographic outcomes. To compare the 5-year clinical and radiographic outcomes and complications between long fusion constructs with L5-S1 interbody support versus posterolateral fusion (PLF) alone.

SUMMARY OF BACKGROUND DATA

Cadaveric biomechanical studies have suggested that an interbody fusion at L5-S1 is beneficial in long fusion constructs with sacropelvic fixation. However, there is limited data reflecting the superiority of interbody support augmentation in optimizing arthrodesis and deformity correction relative to PLF alone.

METHODS

Eighty-eight consecutive adults with spinal deformity who underwent at minimum T11-pelvis posterior pedicle screw instrumentation with 5-year follow-up were included. Two cohorts were compared based on technique used at the lumbosacral junction (L5-S1): (A) no interbody (PLF; n = 23), or (B) interbody support at L5-S1 (IB; n = 65). Radiographic measurements and clinical outcome measures were compared at multiple time points. Complications were recorded and compared.

RESULTS

No differences in baseline patient characteristics between cohorts. One nonunion occurred at L5-S1 in the PLF group (P = 0.091). Initial postop sagittal alignment was better in the IB group (PLF: 6.46 cm, IB: 2.48 cm, P = 0.007); however, this was not maintained over long-term follow-up. No significant differences in proximal junctional kyphosis (PLF: 7/23, IB: 9/65, P = 0.076). Proximal junctional failure was more frequent in the PLF group (PLF: 6/23, IB: 6/65, P = 0.043). No significant differences in complications were found. Both cohorts had improvement from baseline pain and functional scores.

CONCLUSION

There is no absolute long-term advantage for lumbar interbody support in adult spinal deformity patients undergoing spinal arthrodesis to the pelvis.Level of Evidence: 3.

Planned two-stage surgery using lateral lumbar interbody fusion and posterior corrective fusion: a retrospective study of perioperative complications

PURPOSE

To determine the effect of planned two-stage surgery using lateral lumbar interbody fusion (LLIF) on the perioperative complication rate following corrective fusion surgery in patients with kyphoscoliosis.

METHODS

Consecutive patients with degenerative scoliosis who underwent corrective fusion were divided into a control group that underwent single-stage posterior-only surgery and a group that underwent planned two-staged surgery with LLIF and posterior corrective fusion. We collected the patient background and surgical data and assessed the perioperative complication rates. We also investigated spinopelvic parameters and patient-reported outcome measurements (PROMs).

RESULTS

One hundred and thirty-eight patients of mean age 69.8 (range, 50-84) years who met the study inclusion criteria were included. The two-stage group (n = 75) underwent a staged anterior-posterior surgical procedure, and the control group (n = 63) underwent single-stage surgery. There was no significant between-group difference in the incidence of perioperative complications, except for deep wound infection (reoperation is necessary for surgical site infection). Revision surgery within 3 months of the initial surgery was more common in the control group (n = 8, 12.7%) than in the two-stage group (n = 3, 4.0%). Spinopelvic parameters and PROMs were significantly better in the two-stage group at 2 years postoperatively.

CONCLUSION

The complication rate for planned two-stage surgery was similar to that of previous posterior-only single-stage surgery. However, early reoperation was less common, and the degree of spinal correction and clinical results were significantly better after two-stage surgery.

The minimally invasive interbody selection algorithm for spinal deformity

OBJECTIVE

Minimally invasive surgery (MIS) for spinal deformity uses interbody techniques for correction, indirect decompression, and arthrodesis. Selection criteria for choosing a particular interbody approach are lacking. The authors created the minimally invasive interbody selection algorithm (MIISA) to provide a framework for rational decision-making in MIS for deformity.

METHODS

A retrospective data set of circumferential MIS (cMIS) for adult spinal deformity (ASD) collected over a 5-year period was analyzed by level in the lumbar spine to identify surgeon preferences and evaluate segmental lordosis outcomes. These data were used to inform a Delphi session of minimally invasive deformity surgeons from which the algorithm was created. The algorithm leads to 1 of 4 interbody approaches: anterior lumbar interbody fusion (ALIF), anterior column release (ACR), lateral lumbar interbody fusion (LLIF), and transforaminal lumbar interbody fusion (TLIF). Preoperative and 2-year postoperative radiographic parameters and clinical outcomes were compared.

RESULTS

Eleven surgeons completed 100 cMISs for ASD with 338 interbody devices, with a minimum 2-year follow-up. The type of interbody approach used at each level from L1 to S1 was recorded. The MIISA was then created with substantial agreement. The surgeons generally preferred LLIF for L1-2 (91.7%), L2-3 (85.2%), and L3-4 (80.7%). ACR was most commonly performed at L3-4 (8.4%) and L2-3 (6.2%). At L4-5, LLIF (69.5%), TLIF (15.9%), and ALIF (9.8%) were most commonly utilized. TLIF and ALIF were the most selected approaches at L5-S1 (61.4% and 38.6%, respectively). Segmental lordosis at each level varied based on the approach, with greater increases reported using ALIF, especially at L4-5 (9.2°) and L5-S1 (5.3°). A substantial increase in lordosis was achieved with ACR at L2-3 (10.9°) and L3-4 (10.4°). Lateral interbody arthrodesis without the use of an ACR did not generally result in significant lordosis restoration. There were statistically significant improvements in lumbar lordosis (LL), pelvic incidence-LL mismatch, coronal Cobb angle, and Oswestry Disability Index at the 2-year follow-up.

CONCLUSIONS

The use of the MIISA provides consistent guidance for surgeons who plan to perform MIS for deformity. For L1-4, the surgeons preferred lateral approaches to TLIF and reserved ACR for patients who needed the greatest increase in segmental lordosis. For L4-5, the surgeons' order of preference was LLIF, TLIF, and ALIF, but TLIF failed to demonstrate any significant lordosis restoration. At L5-S1, the surgical team typically preferred an ALIF when segmental lordosis was desired and preferred a TLIF if preoperative segmental lordosis was adequate.

Sudden, Transient Intraoperative Hypotension During the Use of the Cantilever Technique for Correction of Adult Spine Deformity

Intraoperative hypotension is a common but critical complication of spinal surgery. However, it is uncommon to experience sudden transient intraoperative hypotension in patients undergoing surgery for adult spine deformity (ASD) without the presence of major vascular injury, spinal cord injury, or cardiac events. We report a patient who experienced sudden transient intraoperative hypotension during the use of the cantilever technique for correction of an ASD. A 58-year-old woman underwent two-stage surgery (anterior correction followed by posterior fusion) for an ASD that caused low back pain. During the posterior fusion procedure, she experienced sudden transient intraoperative hypotension during the use of a cantilever technique. As soon as we paused the use of this technique, her hypotension resolved. Postoperative radiography revealed excessive segmental lordosis at the L4/5 level, suggesting an accidental rupture of the anterior longitudinal ligament (ALL). We believe that the mechanism of our patient’s sudden hypotension was a decrease in venous return due to compression and stretching of the inferior vena cava at the time of rod application when the use of the cantilever technique caused ALL rupture. Sudden hypotension during posterior spinal correction surgery is possible, especially in patients with a ruptured ALL.

Soft Landing technique as a possible prevention strategy for proximal junctional failure following adult spinal deformity surgery

Background

This cross sectional study describes a "Soft Landing" strategy utilizing hooks for minimizing proximal junctional kyphosis (PJK) and proximal junctional failure (PJF). The technique creates a gradual transition from a rigid segmental construct to unilateral hooks at the upper instrumented level and preservation of the soft tissue attachments on the contralateral side of the hooks. Authors devise a novel classification system for better grading of PJK severity.

Methods

Thirty-nine consecutive adult spinal deformity (ASD) patients at a single institution received the "Soft Landing" technique. The proximal junctional angle was measured preoperatively and at last follow-up using standing 36-inch spinal radiographs. Changes in proximal junctional angle and rates of PJK and PJF were measured and used to create a novel classification system for evaluating and categorizing ASD patients postoperatively.

Results

The mean age of the cohort was 61.4 years, and 90% of patients were women. Average follow up was 2.2 years. The mean change in proximal junctional angle was 8° (SD 7.4°) with the majority of patients (53%) experiencing less than 10° and only 1 patients with proximal junctional angle over 20°. Four patients (10%) needed additional surgery for proximal extension of the uppermost instrumented vertebra (UIV) secondary to PJF.

Conclusions

Soft Landing technique is a possibly effective treatment strategy to prevent PJK and PJF following ASD that requires further evaluation. The described classification system provides management framework for better grading of PJK. The "Soft Landing" technique warrants further comparison to other techniques currently used to prevent both PJK and failure.

Clinical utility of enhanced recovery after surgery pathways in pediatric spinal deformity surgery: systematic review of the literature

OBJECTIVES

More than 7500 children undergo surgery for scoliosis each year, at an estimated annual cost to the health system of $1.1 billion. There is significant interest among patients, parents, providers, and payors in identifying methods for delivering quality outcomes at lower costs. Enhanced recovery after surgery (ERAS) protocols have been suggested as one possible solution. Here the authors conducted a systematic review of the literature describing the clinical and economic benefits of ERAS protocols in pediatric spinal deformity surgery.

METHODS

The authors identified all English-language articles on ERAS protocol use in pediatric spinal deformity surgery by using the following databases: PubMed/MEDLINE, Web of Science, Cochrane Reviews, EMBASE, CINAHL, and OVID MEDLINE. Quantitative analyses of comparative articles using random effects were performed for the following clinical outcomes: 1) length of stay (LOS); 2) complication rate; 3) wound infection rate; 4) 30-day readmission rate; 5) reoperation rate; and 6) postoperative pain scores.

RESULTS

Of 950 articles reviewed, 7 were included in the qualitative analysis and 6 were included in the quantitative analysis. The most frequently cited benefits of ERAS protocols were shorter LOS, earlier urinary catheter removal, and earlier discontinuation of patient-controlled analgesia pumps. Quantitative analyses showed ERAS protocols to be associated with shorter LOS (mean difference -1.12 days; 95% CI -1.51, -0.74; p < 0.001), fewer postoperative complications (OR 0.37; 95% CI 0.20, 0.68; p = 0.001), and lower pain scores on postoperative day (POD) 0 (mean -0.92; 95% CI -1.29, -0.56; p < 0.001) and POD 2 (-0.61; 95% CI -0.75, -0.47; p < 0.001). There were no differences in reoperation rate or POD 1 pain scores. ERAS-treated patients had a trend toward higher 30-day readmission rates and earlier discontinuation of patient-controlled analgesia (both p = 0.06). Insufficient data existed to reach a conclusion about cost differences.

CONCLUSIONS

The results of this systematic review suggest that ERAS protocols may shorten hospitalizations, reduce postoperative complication rates, and reduce postoperative pain scores in children undergoing scoliosis surgery. Publication biases exist, and therefore larger, prospective, multicenter data are needed to validate these results.

Incidence and Risk Factors of Anterior Longitudinal Ligament Rupture After Posterior Corrective Surgery Using Lateral Lumbar Interbody Fusion for Adult Spinal Deformity

STUDY DESIGN

A retrospective single-center study.

OBJECTIVE

The objective of this study was to assess the incidence of anterior longitudinal ligament rupture (ALLR) and to identify the risk factors for ALLR in patients with adult spinal deformity (ASD).

SUMMARY OF BACKGROUND DATA

Lateral lumbar interbody fusion (LIF) has been widely used for ASD surgery. However, ALLR has been occasionally identified after posterior spinal correction surgery.

MATERIALS AND METHODS

The study included 43 consecutive patients (8 male and 35 female patients) who underwent posterior corrective surgery involving LIF (128 levels) for ASD between 2014 and 2018. The mean age was 72±7 years (range: 62-81 y), and the minimum follow-up period was 1 year [mean: 34±15 mo (range: 12-58 mo)]. Posterior correction and fusion surgery using the cantilever technique was performed following LIF. Oblique LIF was performed in 27 patients, and extreme lateral interbody fusion (XLIF) was performed in 16 patients. The mean number of spinal fused levels was 8.9±1.8 levels (range: 8-15), and the mean number of LIF levels was 3±0.6 levels (range: 2-4). ALLR was considered if a LIF cage showed no contact with the vertebral endplates. The radiographic parameters were thoracic kyphosis, lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt, and sagittal vertical axis.

RESULTS

ALLR occurred in 10 patients (22%) and at 11 levels (8.6%). XLIF and preexisting osteoporotic vertebral fracture were identified as independent risk factors for ALLR. The change in LL was ∼10 degrees greater in the ALLR group than in the non-ALLR group (P=0.017), and overcorrection was observed in the ALLR group (PI-LL: -7.9±7 degrees). The change in the segmental lordotic angle at the ALLR level was much larger than after LIF and correction surgery. ALLR-related reoperation was performed in 2 cases (decompression surgery owing to posterior impingement and rod breakage).

CONCLUSIONS

ALLR occurred in 10 patients (22%). XLIF and preexisting osteoporotic vertebral fracture were independent risk factors for ALLR. Overcorrection was observed in patients with ALLR.

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.

Efficacy and radiographic analysis of oblique lumbar interbody fusion in treating lumbar degenerative spondylolisthesis with sagittal imbalance

The aim of this study was to evaluate the effectiveness of OLIF (oblique lumbar interbody fusion) in the treatment of lumbar degenerative spondylolisthesis with sagittal imbalance. Fifty-nine patients were included in our analysis. Included patients were divided into 2 groups according to the surgical techniques: PLIF (posterior lumbar interbody fusion) (n = 31) and OLIF + PSF (OLIF combined with posterior spinal fixation) (n = 28). Perioperative radiographic parameters, complications, and clinical outcome from each group were assessed and compared. The operation time for both groups was 165.1 min in the OLIF group and 182.1 min in the PLIF group (P < 0.05). The intraoperative blood loss was 190.6 ml in the OLIF group and 356.3 ml in the PLIF group (P < 0.05). The number of intraoperative and postoperative complications for both groups was 7 in the OLIF group and 11 in the PLIF group. Significant clinical improvement was observed in VAS scores and ODI when comparing preoperative evaluation and final follow-up. The preoperative SVA (the distance from the posterosuperior corner of S1body to the C7 plumb line), PI (pelvic incidence), LL (lumbar lordosis), PI-LL mismatch, DH (disc height), and lumbar Cobb angles of both groups were similar. The postoperative and final follow-up SVA, LL, PI-LL mismatch, and disc height were improved in both groups, and a statistical difference was found between both groups (P < 0.05). An improvement of SVA, LL, PI-LL mismatch, and disc height at the OLIF group was better than that found at the PLIF group. An improvement in radiographic and clinical outcomes for the OLIF group was better than that seen for the PLIF group. Then, OLIF had a more curative effect in lumbar degenerative spondylolisthesis with sagittal imbalance.

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.

Minimally invasive multilevel lateral lumbar interbody fusion with posterior column osteotomy compared with pedicle subtraction osteotomy for adult spinal deformity

BACKGROUND CONTEXT

Pedicle subtraction osteotomy (PSO) is highly effective as a sagittal correction approach in patients with adult spinal deformity, but relevant issues such as surgical complexity and long-term complications limit its applicability. Recently, minimally invasive techniques have been reported to be useful for surgical treatment of adult spinal deformity; however, few reports have directly compared these techniques with PSO.

PURPOSE

The purpose of this study was to evaluate the radiological and clinical efficacies of oblique lateral interbody fusion (OLIF) with posterior column osteotomy (PCO) using stiff rods (6.35-mm cobalt chrome [CoCr]).

STUDY DESIGN

Retrospective comparative study.

PATIENT SAMPLE

One-hundred six patients (average age 71.3 years) diagnosed with adult spinal deformity presenting with sagittal imbalance for whom follow-up of over 2 years after sagittal correction (between 2013 and 2017) was available.

OUTCOME MEASURES

Description and analysis of X-ray, computed tomography scans, operative time, estimated blood loss, and clinical outcomes (Oswestry Disability Index [ODI] and Visual Analog Scale [VAS]).

METHODS

A comparative analysis was performed evaluating spinopelvic parameters and clinical outcomes including the ODI, VAS, and complications in patients who underwent PSO (PSO group; n=65) or multilevel prepsoas OLIF combined with PCO and open posterior spinal fusion using 6.35-mm CoCr rods (OLIF group; n=41). The authors have no conflicts of interest to disclose.

RESULTS

There were no differences in preoperative spinopelvic parameters between the PSO and OLIF groups. Although no differences were observed between the two groups in terms of postoperative SVA (-12.66 mm vs. -16.44 mm), postoperative lumbar lordosis (-71.46° vs. -72.55°), lumbar lordosis correction (77.96° vs. 73.54°), or postoperative pelvic tilt (9.35° vs. 7.17°), the estimated blood loss was significantly lower in the OLIF group (2824 mL vs. 1736 mL, p<.05). No differences were observed in clinical outcomes (ODI, VAS, and clinical complications), proximal junctional kyphosis, and spinopelvic parameters between the two groups 2 years after surgery. However, pseudarthrosis during the follow-up period, including rod fracture, occurred less frequently in the OLIF group compared with that in the PSO group (p<.05). OLIF was performed from the T12-L1 to L5-S1 regions (124 segments), with an average of three segments per patient. The computed tomography scans immediately after surgery showed an average segmental correction of -18° and 12.9% (16 segments) of 124 segments showed a correction angle of >30°.

CONCLUSIONS

Multilevel OLIF with PCO using a stiff rod to treat severe sagittal imbalance resulted in similar levels of sagittal balance and lordosis correction as obtained by PSO. Multilevel OLIF with PCO using a stiff rod can be an effective alternative to PSO for patients with severe sagittal imbalance.

Sexual Dysfunction Secondary to Lumbar Stiffness in Adult Spinal Deformity Patients Before and After Long-Segment Spinal Fusion

OBJECTIVE

Sexual function is an important factor contributing to quality of life. Adult spinal deformity (ASD) patients may have sexual limitations due to lumbar spinal stiffness that may be affected by long-segment fusion.

METHODS

This study utilized a multicenter, prospectively defined, consecutive cohort of ASD patients. The primary outcome in this study was the Lumbar Stiffness Disability Index (LSDI) question 10: "Choose the statement that best describes the effect of low back stiffness on your ability to engage in sexual intercourse".

RESULTS

In total, 368 patients were included in this study, including 76 men and 292 women, of which 80.7% (n = 293) underwent 9 or more level fusion and 74.4% (n = 270) had pelvic fixation. Baseline LSDI sexual function scores averaged 1.7 (SD 1.3), which improved to 1.3 (SD 1.2) at 2-year follow-up (P = 0.0008). After adjusting for confounding factors, worse LSDI sexual function score was strongly associated with worse Oswestry Disability Index, Scoliosis Research Society-22r total, and SF-36 Physical Component Summary and Mental Component Summary scores at both baseline and 2-year follow-up (p<0.05 for all comparisons). Predictors of poorer baseline sexual function included older age, increased SVA, and increased back pain (p<0.05 for all comparisons). Predictors of improvement in sexual function at 2-year follow-up included sagittal vertical axis improvement (P = 0.0032) and decreased postoperative back pain (P < 0.0001).

CONCLUSIONS

This study found that sexual dysfunction scores due to lumbar stiffness significantly improved after surgery for ASD. Additionally, lumbar stiffness-related sexual dysfunction is strongly related to overall outcome measured by Oswestry Disability Index and Scoliosis Research Society-22r total score, highlighting the importance of sexual health on overall outcome in ASD patients.

Assessment of Patient Outcomes and Proximal Junctional Failure Rate of Patients with Adult Spinal Deformity Undergoing Caudal Extension of Previous Spinal Fusion

OBJECTIVE

This case series examined patients undergoing caudal extension of prior fusion without alteration of the prior upper instrumented vertebra (UIV) to assess patient outcomes and rates of proximal junctional kyphosis (PJK)/proximal junctional failure (PJF).

METHODS

Patients eligible for 2-year minimum follow-up undergoing caudal extension of prior fusion with unchanged UIVs were identified. These patients were evaluated for PJK/PJF, and patient reported outcomes were recorded.

RESULTS

In total, 40 patients were included. Mean follow-up duration was 2.2 ± 0.3 years. Patients in this cohort had poor preoperative sagittal alignment (pelvic incidence minus lumbar lordosis [PI-LL] 26.7°, T1 pelvic angle [TPA] 29.0°, sagittal vertical axis [SVA] 93.4 mm) and achieved substantial sagittal correction (ΔSVA -62.2 mm, ΔPI-LL -19.8°, ΔTPA -11.1°) after caudal extension surgery. At final follow-up, there was a 0% rate of PJF among patients undergoing caudal extension of previous fusion without creation of a new UIV, but 27.5% of patients experienced PJK. Patients experienced significant improvement in both the Oswestry Disability Index and Scoliosis Research Society-22r total score at 2 years postoperatively (P < 0.05). In total, 7.5% (n = 3) of patients underwent further revision, at an average of 1.1 ± 0.54 years after the surgery with unaltered UIV. All 3 of these patients underwent revision for rod fracture with no revisions for PJK/PJF.

CONCLUSIONS

Patients undergoing caudal extension of previous fusions for sagittal alignment correction have high rates of clinical success, low revision surgery rates, and very low rates of PJF. Minimizing repetitive tissue trauma at the UIV may result in decreased PJF risk because the PJF rate in this cohort of patients with unaltered UIV is below historical PJF rates of patients undergoing sagittal balance correction.

Team Approach: Safety and Value in the Practice of Complex Adult Spinal Surgery

Surgical management of complex adult spinal deformities is of high risk, with a substantial risk of operative mortality. Current evidence shows that potential risk and morbidity resulting from surgery for complex spinal deformity may be minimized through risk-factor optimization. The multidisciplinary team care model includes neurosurgeons, orthopaedic surgeons, physiatrists, anesthesiologists, hospitalists, psychologists, physical therapists, specialized physician assistants, and nurses. The multidisciplinary care model mimics previously described integrated care pathways designed to offer a structured means of providing a comprehensive preoperative medical evaluation and evidence-based multimodal perioperative care. The role of each team member is illustrated in the case of a 66-year-old male patient with previous incomplete spinal cord injury, now presenting with Charcot spinal arthropathy and progressive vertebral-body destruction resulting in lumbar kyphosis.

Upper-thoracic versus lower-thoracic upper instrumented vertebra in adult spinal deformity patients undergoing fusion to the pelvis: surgical decision-making and patient outcomes

OBJECTIVE

Optimal patient selection for upper-thoracic (UT) versus lower-thoracic (LT) fusion during adult spinal deformity (ASD) correction is challenging. Radiographic and clinical outcomes following UT versus LT fusion remain incompletely understood. The purposes of this study were: 1) to evaluate demographic, radiographic, and surgical characteristics associated with choice of UT versus LT fusion endpoint; and 2) to evaluate differences in radiographic, clinical, and health-related quality of life (HRQOL) outcomes following UT versus LT fusion for ASD.

METHODS

Retrospective review of a prospectively collected multicenter ASD database was performed. Patients with ASD who underwent fusion from the sacrum/ilium to the LT (T9-L1) or UT (T1-6) spine were compared for demographic, radiographic, and surgical characteristics. Outcomes including proximal junctional kyphosis (PJK), reoperation, rod fracture, pseudarthrosis, overall complications, 2-year change in alignment parameters, and 2-year HRQOL metrics (Lumbar Stiffness Disability Index, Scoliosis Research Society-22r questionnaire, Oswestry Disability Index) were compared after controlling for confounding factors via multivariate analysis.

RESULTS

Three hundred three patients (169 LT, 134 UT) were evaluated. Independent predictors of UT fusion included greater thoracic kyphosis (odds ratio [OR] 0.97 per degree, p = 0.0098), greater coronal Cobb angle (OR 1.06 per degree, p < 0.0001), and performance of a 3-column osteotomy (3-CO; OR 2.39, p = 0.0351). While associated with longer operative times (ratio 1.13, p < 0.0001) and greater estimated blood loss (ratio 1.31, p = 0.0018), UT fusions resulted in greater sagittal vertical axis improvement (-59.5 vs -41.0 mm, p = 0.0035) and lower PJK rates (OR 0.49, p = 0.0457). No significant differences in postoperative HRQOL measures, reoperation, or overall complication rates were detected between groups (all p > 0.1).

CONCLUSIONS

Greater deformity and need for 3-CO increased the likelihood of UT fusion. Despite longer operative times and greater blood loss, UT fusions resulted in better sagittal correction and lower 2-year PJK rates following surgery for ASD. While continued surveillance is necessary, this information may inform patient counseling and surgical decision-making.

[Effectiveness of short fusion versus long fusion for degenerative scoliosis with a Cobb angle of 20-40° combined with spinal stenosis]

Objective

To compare the effectiveness of decompression and short fusion or long fusion for degenerative scoliosis (DS) with a Cobb angle of 20-40° combined with spinal stenosis.

Methods

The clinical data of 50 patients with DS who were treated with decompression combined with short fusion or long fusion between January 2015 and May 2017 were retrospectively analysed. Patients were divided into long fusion group (fixed segments>3, 23 cases) and short fusion group (fixed segments≤3, 27 cases). There was no significant difference in gender, age, disease duration, and preoperative visual analogue scale (VAS) score of leg pain, Oswestry disability index (ODI), thoracic kyphosis (TK), thoracolumbar kyphosis (TLK), pelvic incidence (PI), pelvic title (PT), and sacral slope (SS) between the two groups ( P>0.05); however, the VAS score of low back pain, Cobb angle, and sagittal vertical axis (SVA) in long fusion group were significantly higher than those in short fusion group ( P<0.05), and the lumbar lordosis (LL) was significantly lower than that in short fusion group ( t=2.427, P=0.019). The operation time, intraoperative blood loss, fluoroscopy times, hospital stay, and complications were recorded and compared. The VAS scores of low back pain and leg pain and ODI score were used to evaluate the clinical outcomes before operation and at last follow-up. X-ray films of the whole spine in standard standing position were taken before operation, at 6 months after operation, and at last follow-up, and the spino-pelvic parameters were measured.

Results

The operation time, intraoperative blood loss, and fluoroscopy times in the short fusion group were significantly less than those in the long fusion group ( P<0.05); there was no significant difference in hospital stay between the two groups ( t=0.933, P=0.355). The patients were followed up 12-46 months with an average of 22.3 months. At last follow-up, the VAS scores of low back pain and leg pain and ODI score significantly improved when compared with those before operation ( P<0.05). Except for the improvement of VAS score of low back pain ( t=8.332, P=0.000), the differences of the improvements of the other scores between the two groups were not significant ( P>0.05). The Cobb angle, SVA, TLK, and PT significantly decreased, while SS and LL significantly increased in the long fusion group ( P<0.05), while the Cobb angle and PT significantly decreased and SS significantly increased in the short fusion group at last follow-up ( P<0.05). There was no significant difference in spino-pelvic parameters between the two groups at 6 months after operation and at last follow-up ( P>0.05). The improvements of Cobb angle, SVA, LL, PT, and SS in the long fusion group were significantly higher than those in the short fusion group at last follow-up ( P<0.05). There was no perioperative death in both groups. The incidence of complications in the long fusion group was 34.8% (8/23), which was significantly higher than that in the short fusion group [11.1% (3/27)] ( χ ²=4.056, P=0.034).

Conclusion

The DS patients with the Cobb angle of 20-40°can achieve satisfactory clinical outcomes and improve the spino-pelvic parameters by choosing appropriate fixation levels. Short fusion has less surgical trauma and fewer complications, whereas long fusion has more advantages in enhancing spino-pelvic parameters and relieving low back pain.

Correction of marked sagittal deformity with circumferential minimally invasive surgery using oblique lateral interbody fusion in adult spinal deformity

BACKGROUND

Spinal surgery performed entirely with minimally invasive surgery is referred to as circumferential MIS (cMIS). However, cMIS still has a limited sagittal correction capability for adult spinal deformity (ASD) with a marked sagittal deformity. We investigated the effectiveness of cMIS using oblique lateral interbody fusion (OLIF) and percutaneous posterior spine fixation in correcting marked sagittal deformity.

METHODS

This study retrospectively evaluated 23 patients with ASD with marked sagittal deformity who underwent cMIS using OLIF without osteotomy and were followed-up for at least 24 months (whole group). The whole group was divided into the following two groups according to the type of interbody fusion at L5-S1: the OLIF51 group (n = 13) underwent OLIF at L1-L5 and L5-S1 and the TLIF51 group (n = 10) underwent OLIF at L1-L5 and transforaminal lumbar interbody fusion (TLIF) at L5-S1.

RESULTS

Sagittal vertebral axis (SVA; 125.7 vs. 29.5 mm, p < 0.001), lumbar lordosis (LL; 18.2° vs. 51.7°, p < 0.001), and pelvic incidence-LL mismatch (PI-LL, 35.5° vs. 5.3°) significantly improved postoperatively in the whole group. The OLIF51 group showed significantly higher postoperative LL than the TLIF51 group (55.5° vs. 46.9°, p < 0.001). OLIF yielded a significantly greater disc angle at L5-S1 than did TLIF (18.4° vs. 6.9°, p < 0.001). Proximal junctional kyphosis occurred significantly earlier in the OLIF51 group than in the TLIF51 group (8.6 vs. 26.3 months, p < 0.001).

CONCLUSION

Successful sagittal correction in ASD patients with marked sagittal deformity was achieved with cMIS using OLIF. OLIF at L5-S1 showed a synergistic effect in sagittal deformity correction by cMIS.