Minimally invasive lateral transpsoas interbody fusion using a stand-alone construct for the treatment of adjacent segment disease of the lumbar spine: review of the literature and report of three cases

Adjacent Segment Disease After Spinal Fusion

» Adjacent segment disease is characterized by a degenerative process adjacent to a previously fused spine segment, with new onset of clinical symptoms such as radiculopathy, myelopathy, or instability.» Etiology is related to the natural history of the disease process, increased biomechanical stress at adjacent segments, clinical factors specific to the individual patient, intraoperative factors, and malalignment.» Treatment is usually nonoperative, but surgical intervention can be indicated. Decompression and fusion remain the mainstay of operative treatment, and isolated decompression should be considered in specific cases.» Further randomized controlled trials are needed to establish how the treatment should progress, particularly with the development of minimally invasive and endoscopic surgery.

Oblique Lumbar Interbody Fusion Using a Stand-Alone Construct for the Treatment of Adjacent-Segment Lumbar Degenerative Disease

Objective

Adjacent-segment disease (ASD) is common in patients undergone previous lumbar fusion. A typical revision treatment from posterior approach requires management of postoperative scar tissue and previously implanted instrumentation. An oblique lumbar interbody fusion (OLIF) approach allows surgeon to reduce the potential risk of posterior approach. This study aimed to analyze the clinical and radiographic efficacy of stand-alone OLIF for the treatment of lumbar adjacent-segment disease.

Methods

A total of 13 consecutive patients who underwent stand-alone OLIF for the treatment of adjacent-segment disease from December 2016 to January 2019 were reviewed. Visual analog scale (VAS) of back pain and leg pain and the Oswestry Disability Index (ODI) before surgery and at last postoperative clinic visits were obtained. Radiography, CT and MRI before and at last follow-up after surgery was evaluated in all patients.

Results

During the study period, 13 cases were successfully treated with stand-alone OLIF. The mean follow-up was 17.7 ± 8.3 months. The back pain VAS improved from 6.2 ± 1.0 to 2.0 ± 1.1 (P < 0.01), and the leg pain VAS improved from 7.0 ± 1.9 to 1.0 ± 0.9 (P < 0.01). ODI improved from 28.0 ± 7.5 to 10.8 ± 4.0 (P < 0.01). The disc height (DH) increased from 9 ± 2 to 12 ± 2 mm (P < 0.01), the cross-sectional area (CSA) of spinal canal increased from 85 ± 26 to 132 ± 24 mm² (P < 0.01), the foraminal height increased from 17 ± 2 to 21 ± 3 mm (P < 0.01) and the CSA of foramen increased from 95 ± 25 to 155 ± 36 mm² (P < 0.01). Cage subsidence was observed in 2 cases.

Conclusions

Stand-alone OLIF provides a safe and effective alternative way to treat ASD.

Early Outcomes of 3D-printed Porous Titanium versus Polyetheretherketone (PEEK) Cage Implantation for Standalone Lateral Lumbar Interbody Fusion in the Treatment of Symptomatic Adjacent Segment Degeneration

OBJECTIVE

This study compared outcomes of 3D-printed porous titanium (Ti) versus polyetheretherketone (PEEK) cage implantation for standalone lateral lumbar interbody fusion (SA-LLIF) in the treatment of symptomatic adjacent segment degeneration (ASD).

METHODS

44 patients (59 levels) underwent SA-LLIF with Ti or PEEK cages between 10/2016 and 07/2020. The primary outcome was cage subsidence according to Marchi et al. Secondary outcomes included revision/recommendations for revision surgery, back/leg pain severity, changes in disc/foraminal height and global/segmental lumbar lordosis.

RESULTS

44 patients (21 female) were included with a mean age at surgery of 61.8±11.5 years, average radiological follow-up of 12.5±8.2 and clinical follow-up of 11.0±7.1 months. The overall subsidence rate was significantly less in the Ti versus PEEK group (20% vs. 58.8%; p=0.004). Revision was recommended to none of the patients in the Ti and 3 in the PEEK group (p=0.239). Furthermore, patients in the Ti group showed significantly better improvement in back pain NRS score (p=0.001). Disc height (p<0.001) and foraminal height restoration (p=0.011) were statistically significant in the Ti group, whereas only disc height restoration was significant in the PEEK group (p=0.003).

CONCLUSION

In patients undergoing SA-LLIF for ASD treatment, 3D-printed Ti cages had significantly lower overall subsidence rate compared to PEEK cages. Furthermore, Ti cages resulted in fewer recommendations for revision surgery. Whether greater pain reduction in the Ti group is associated with earlier or higher fusion rates needs to be further elucidated.

Complications associated with L4-5 anterior retroperitoneal trans-psoas interbody fusion: a single institution series

Background

Lateral lumbar interbody fusion (LLIF), first described in the literature in 2006 by Ozgur et al., involves direct access to the lateral disc space via a retroperitoneal trans-psoas tubular approach. Neuromonitoring is vital during this approach since the surgical corridor traverses the psoas muscle where the lumbar plexus lies, risking injury to the lumbosacral plexus that could result in sensory or motor deficits. The risk of neurologic injury is especially higher at L4-5 due to the anatomy of the plexus at this level. Here we report our single-center clinical experience with L4-5 LLIF.

Methods

A retrospective chart review of all patients who underwent an L4-5 LLIF between May 2016 and March 2019 was performed. Baseline demographics and clinical characteristics, such as body mass index (BMI), medical comorbidities, surgical history, tobacco status, operative time and blood loss, length of stay (LOS), and post-op complications were recorded.

Results

A total of 220 (58% female and 42% male) cases were reviewed. The most common presenting pathology was spondylolisthesis. The average age, BMI, operative time, blood loss, and LOS were 64.6 years, 29 kg/m², 214 min, 75 cc, and 2.5 days respectively. A review of post-operative neurologic deficits revealed 31.4% transient hip flexor weakness and 4.5% quadricep weakness on the approach side. At 3-week follow-up, 9.1% of patients experienced mild hip flexor weakness (4 or 4+/5), 0.9% reported mild quadricep weakness, and 9.5% reported anterior thigh dysesthesias; 93.2% of patients were discharged home and 2.3% were readmitted within the first 30 days post discharge. Female sex, higher BMI and longer operative time were associated with hip flexor weakness.

Conclusions

LLIF at L4-5 is a safe, feasible, and versatile approach to the lumbar spine with an acceptable approach-related sensory and motor neurologic complication rates.

Comparing Oblique Lumbar Interbody Fusion with Lateral Screw Fixation and Transforaminal Full-Endoscopic Lumbar Discectomy (OLIF-TELD) and Posterior Lumbar Interbody Fusion (PLIF) for the Treatment of Adjacent Segment Disease

Background

A potential long-term complication of lumbar fusion is the development of adjacent segment disease (ASD), which may require surgical intervention and adversely affect outcomes. A high incidence of recurrent ASD was reported in patients who underwent the second (repeat) PLIF for symptomatic ASD. Herein, a feasible method, oblique lumbar interbody fusion combined with transforaminal endoscopic lumbar discectomy (OLIF-TELD) for dealing with adjacent lumbar disc herniation with upward or downward migration after lumbar spinal fusion, was proposed.

Methods

A total of 19 patients who underwent revision surgery at ASD were consecutively enrolled. Clinical efficacy analysis included operative time, intraoperative bleeding, visual analogue scale (VAS) score, Oswestry dysfunction index (ODI) score, and Japanese orthopaedic association (JOA) assessment treatment score.

Results

Among them, 11 patients were treated in a new surgical strategy, which is OLIF-TELD, and 8 patients underwent PLIF. There was no statistically significant difference between the two groups in terms of age, gender, and preoperative scores of VAS, ODI, and JOA. The operative duration was shorter, and intraoperative bleeding was less in the OLIF-TELD group compared with the PLIF group. PLIF had the greatest blood loss, and the OLIF-TELD group had lower VAS scores than the PLIF group postoperatively. The symptoms of all patients improved postoperatively with statistical significance.

Conclusion

OLIF with lateral screw fixation combined with TELD may be an alternative surgical method for the treatment of adjacent lumbar disc herniation with upward or downward migration after lumbar fusion surgery.

Minimally Invasive Lateral Lumbar Interbody Fusion for Clinical Adjacent Segment Pathology: A Comparative Study With Conventional Posterior Lumbar Interbody Fusion

STUDY DESIGN

This was a retrospective comparative study.

OBJECTIVE

The main objective of this article was to evaluate the clinical and radiologic efficacies of minimally invasive lateral lumbar interbody fusion (LLIF) for clinical adjacent segment pathology (ASP).

SUMMARY OF BACKGROUND DATA

Minimally invasive techniques have been increasingly applied for spinal surgery. No report has compared LLIF with conventional posterior lumbar interbody fusion for clinical ASP.

METHODS

Forty patients undergoing LLIF with posterior fusion (hybrid surgery) were compared with 40 patients undergoing conventional posterior lumbar interbody fusion (posterior surgery). The radiologic outcomes including indirect decompression in hybrid surgery group, and clinical outcomes such as the Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) were assessed. Postoperative major complications and reoperations were also compared between the 2 groups.

RESULTS

Correction of coronal Cobb's angle and segmental lordosis in the hybrid surgery were significantly greater postoperatively (2.8 vs. 0.9 degrees, P=0.012; 7.4 vs. 2.5 degrees, P=0.009) and at the last follow-up (2.4 vs. 0.5 degrees, P=0.026; 4.8 vs. 0.8 degrees, P=0.016) compared with posterior surgery. As regards indirect decompression of the LLIF, significant increases in thecal sac (83.4 vs. 113.8 mm) and foraminal height (17.8 vs. 20.9 mm) were noted on postoperative magnetic resonance imaging. Although postoperative back VAS (4.1 vs. 5.6, P=0.011) and ODI (48.9% vs. 59.6%, P=0.007) were significantly better in hybrid surgery, clinical outcomes at the last follow-up were similar. Moreover, intraoperative endplate fractures developed in 17.7% and lower leg symptoms occurred in 30.0% of patients undergoing hybrid surgery.

CONCLUSIONS

Hybrid surgery for clinical ASP has advantages of segmental coronal and sagittal correction, and indirect decompression compared with conventional posterior surgery. However, LLIF-related complications such as endplate fracture and lower leg symptoms also developed. LLIF should be performed considering advantages and approach-related complications for the clinical ASP.

Biomechanical Analysis of Stand-alone Lateral Lumbar Interbody Fusion for Lumbar Adjacent Segment Disease

Study design

Biomechanical cadaveric study 

Objective

To compare biomechanical properties of a single stand-alone interbody fusion and a single-level pedicle screw construct above a previous lumbar pedicle fusion.

Summary of background data

Adjacent segment disease (ASD) is spondylosis of adjacent vertebral segments after previous spinal fusion. Despite the consensus that ASD is clinically significant, the surgical treatment of ASD is controversial.

Methods

Lateral lumbar interbody fusion (LLIF) and posterior spinal fusion (PSF) with pedicle screws were analyzed within a validated cadaveric lumbar fusion model. L3-4 vertebral segment motion was analyzed within the following simulations: without implants (intact), L3-4 LLIF-only, L3-4 LLIF with previous L4-S1 PSF, L3-4 PSF with previous L4-S1 PSF, and L4-S1 PSF alone. L3-4 motion values were measured during flexion/extension with and without axial load, side bending, and axial rotation.

Results

L3-4 motion in the intact model was found to be 4.7 ± 1.2 degrees. L3-4 LLIF-only decreased motion to 1.9 ± 1.1 degrees. L3-4 LLIF with previous L4-S1 fusion demonstrated less motion in all planes with and without loading (p < 0.05) compared to an intact spine. However, L3-4 motion with flexion/extension and lateral bending was noted to be greater compared to the L3-S1 construct (p < 0.5). The L3-S1 PSF construct decreased motion to less than 1° in all planes of motion with or without loading (p < 0.05). The L3-4 PSF with previous L4-S1 PSF constructs decreased the flexion/extension motion by 92.4% compared to the intact spine, whereas the L3-4 LLIF with previous L4-S1 PSF constructs decreased motion by 61.2%.

Conclusions

Stand-alone LLIF above a previous posterolateral fusion significantly decreases motion at the adjacent segment, demonstrating its utility in treating ASD without necessitating revision. The stand-alone LLIF is a biomechanically sound option in the treatment of ASD and is advantageous in patient populations who may benefit from less invasive surgical options.

Comparison of Stand-Alone, Transpsoas Lateral Interbody Fusion at L3-4 and Cranial vs Transforaminal Interbody Fusion at L3-4 and L4-5 for the Treatment of Lumbar Adjacent Segment Disease

Study Design

Retrospective cohort study.

Objective

To compare outcomes and complications of stand-alone minimally invasive lateral interbody fusion (LIF) vs revision posterior surgery for the treatment of lumbar adjacent segment disease.

Methods

Adults who underwent LIF or transforaminal lumbar interbody fusion (TLIF) for adjacent segment disease were compared. Exclusion criteria: >grade 1 spondylolisthesis, posterior approach after LIF, and L5/S1 surgery. Patient demographics, estimated blood loss, hospital length of stay, complications, reoperations, health-related quality of life measures, and radiographs were examined. Data were analyzed with the χ², Wilcoxon signed rank, and Mann-Whitney U tests.

Results

A total of 17 LIF and 16 TLIF patients were included. Demographics were similar. Follow up was similar (LIF: 22.9 ± 11.8 months vs TLIF: 22.0 ± 4.6 months; P = .86). The LIF patients had significantly less blood loss (LIF: 36 ± 16 mL vs TLIF: 700 ± 767 mL; P < .001) and shorter length of stay (LIF: 2.6 ± 2.9 days vs TLIF: 3.3 ± 0.9 days; P = .001). There were no intraoperative complications. Revision rate was 4 of 17 in LIF and 3 of 16 in TLIF (P = .73). Baseline health-related quality of life and radiographic measurements were similar. In both groups, back and leg pain scores significantly improved, and in LIF, the Owestry Disability Index, and EuroQol-5D significantly improved. The LIF had a significant increase in intervertebral height (LIF: 4.8 ± 2.9 mm, P < .001, TLIF: 1.3 ± 3.4 mm, P = .37), which was significantly greater for LIF than TLIF (P = .002). Similarly, LIF had a significant increase in segmental lordosis (LIF: 5.6° ± 4.9°, P < .001, TLIF: 3.6° ± 8.6°, P = .16), which was not significantly different between groups.

Conclusions

Patients with adjacent segment disease may receive significant benefit from stand-alone LIF or TLIF. The LIF offers advantages of less blood loss and a shorter hospital stay.

Level of Evidence

3.

Lateral Lumbar Interbody Fusion and in Situ Screw Fixation for Rostral Adjacent Segment Stenosis of the Lumbar Spine

Objective

The purpose of this study is to describe the detailed surgical technique and short-term clinical and radiological outcomes of lateral lumbar interbody fusion (LLIF) and in situ lateral screw fixation using a conventional minimally invasive screw fixation system (MISF) for revision surgery to treat rostral lumbar adjacent segment disease.

Methods

The medical and radiological records were retrospectively reviewed. The surgery was indicated in 10 consecutive patients with rostral adjacent segment stenosis and instability. After the insertion of the interbody cage, lateral screws were inserted into the cranial and caudal vertebra using the MISF through the same LLIF trajectory. The radiological and clinical outcomes were assessed preoperatively and at 1, 3, 6, and 12 months postoperatively.

Results

The median follow-up period was 13 months (range, 3–48 months). Transient sensory changes in the left anterior thigh occurred in 3 patients, and 1 patient experienced subjective weakness; however, these symptoms normalized within 1 week. Back and leg pain were significantly improved (p<0.05). In the radiological analysis, both the segmental angle at the operated segment and anterior disc height were significantly increased. At 6 months postoperatively, solid bony fusion was confirmed in 7 patients. Subsidence and mechanical failure did not occur in any patients.

Conclusion

This study demonstrates that LLIF and in situ lateral screw fixation may be an alternative surgical option for rostral lumbar adjacent segment disease.

Multidisciplinary Evaluation Leads to the Decreased Utilization of Lumbar Spine Fusion: An Observational Cohort Pilot Study

STUDY DESIGN

Observational cohort pilot study.

OBJECTIVE

To determine the impact of a multidisciplinary conference on treatment decisions for lumbar degenerative spine disease.

SUMMARY OF BACKGROUND DATA

Multidisciplinary decision making improves outcomes in many disciplines. The lack of integrated systems for comprehensive care for spinal disorders has contributed to the inappropriate overutilization of spine surgery in the United States.

METHODS

We implemented a multidisciplinary conference involving physiatrists, anesthesiologists, pain specialists, neurosurgeons, orthopaedic spine surgeons, physical therapists, and nursing staff. Over 10 months, we presented patients being considered for spinal fusion or who had a complex history of prior spinal surgery. We compared the decision to proceed with surgery and the proposed surgical approach proposed by outside surgeons with the consensus of our multidisciplinary conference. We also assessed comprehensive demographics and comorbidities for the patients and examined outcomes for surgical patients.

RESULTS

A total of 137 consecutive patients were reviewed at our multidisciplinary conference during the 10-month period. Of these, 100 patients had been recommended for lumbar spine fusion by an outside surgeon. Consensus opinion of the multidisciplinary conference advocated for nonoperative management in 58 patients (58%) who had been previously recommended for spinal fusion at another institution (χ  = 26.6; P < 0.01). Furthermore, the surgical treatment plan was revised as a product of the conference in 28% (16 patients) of the patients who ultimately underwent surgery (χ  = 43.6; P < 0.01). We had zero 30-day complications in surgical patients.

CONCLUSION

Isolated surgical decision making may result in suboptimal treatment recommendations. Multidisciplinary conferences can reduce the utilization of lumbar spinal fusion, possibly resulting in more appropriate use of surgical interventions with better candidate selection while providing patients with more diverse nonoperative treatment options. Although long-term patient outcomes remain to be determined, such multidisciplinary care will likely be essential to improving the quality and value of spine care.

LEVEL OF EVIDENCE

3.

Biomechanical analysis of lateral interbody fusion strategies for adjacent segment degeneration in the lumbar spine

BACKGROUND CONTEXT

Surgical treatment of symptomatic adjacent segment disease (ASD) typically involves extension of previous instrumentation to include the newly affected level(s). Disruption of the incision site can present challenges and increases the risk of complication. Lateral-based interbody fusion techniques may provide a viable surgical alternative that avoids these risks. This study is the first to analyze the biomechanical effect of adding a lateral-based construct to an existing fusion.

PURPOSE

The study aimed to determine whether a minimally invasive lateral interbody device, with and without supplemental instrumentation, can effectively stabilize the rostral segment adjacent to a two-level fusion when compared with a traditional posterior revision approach.

STUDY DESIGN/SETTING

This is a cadaveric biomechanical study of lateral-based interbody strategies as add-on techniques to an existing fusion for the treatment of ASD.

METHODS

Twelve lumbosacral specimens were non-destructively loaded in flexion, extension, lateral bending, and torsion. Sequentially, the tested conditions were intact, two-level transforaminal lumbar interbody fusion (TLIF) (L3-L5), followed by lateral lumbar interbody fusion procedures at L2-L3 including interbody alone, a supplemental lateral plate, a supplemental spinous process plate, and then either cortical screw or pedicle screw fixation. A three-level TLIF was the final instrumented condition. In all conditions, three-dimensional kinematics were tracked and range of motion (ROM) was calculated for comparisons. Institutional funds (<$50,000) in support of this work were provided by Medtronic Spine.

RESULTS

The addition of a lateral interbody device superadjacent to a two-level fusion significantly reduced motion in flexion, extension, and lateral bending (p<.05). Supplementing with a lateral plate further reduced ROM during lateral bending and torsion, whereas a spinous process plate further reduced ROM during flexion and extension. The addition of posterior cortical screws provided the most stable lateral lumbar interbody fusion construct, demonstrating ROM comparable with a traditional three-level TLIF.

CONCLUSIONS

The data presented suggest that a lateral-based interbody fusion supplemented with additional minimally invasive instrumentation may provide comparable stability with a traditional posterior revision approach without removal of the existing two-level rod in an ASD revision scenario.

The Surgical Anatomy of the Lumbosacroiliac Triangle: A Cadaveric Study

OBJECTIVE

The anatomic area delineated medially by the lateral part of the L4-L5 vertebral bodies, distally by the anterior-superior surface of the sacral wing, and laterally by an imaginary line joining the base of the L4 transverse process to the proximal part of the sacroiliac joint, is of particular interest to spine surgeons. We are referring to this area as the lumbo-sacro-iliac triangle (LSIT). Knowledge of LSIT anatomy is necessary during approaches for L5 vertebral and sacral fractures, sacral and iliac tumors, and extraforaminal decompression of the L5 nerve roots.

METHODS

We performed an anatomic dissection of the LSIT in 3 embalmed cadavers (6 triangles), using an anterior and posterior approach.

RESULTS

We identified 3 key tissue planes: the neurological plexus plane, constituted by L4 and L5 nerve roots; an intermediate level constituted by the ileosacral tunnel; and posteriorly, by the lumbosacral ligament, and the posterior muscular plane.

CONCLUSIONS

Improving anatomic knowledge of the LSIT may help surgeons decrease the risk of possible complications. When LSIT pathology is present, a lateral approach corresponding to the tip of the L4 transverse process, medially, is suggested to decrease the risk of vessel and nerve root damage.