Radiographic comparison of lordotic and hyperlordotic implants in L5–S1 anterior lumbar interbody fusion

OBJECTIVE Anterior lumbar interbody fusion (ALIF) used at the lumbosacral junction provides arthrodesis for several indications. The anterior approach allows restoration of lumbar lordosis, an important goal of surgery. With hyperlordotic ALIF implants, several options may be employed to obtain the desired amount of lordosis. In this study, the authors compared the degree of radiographic lordosis achieved with lordotic and hyperlordotic ALIF implants at the L5–S1 segment. METHODS All patients undergoing L5–S1 ALIF from 2 institutions over a 4-year interval were included. Patients < 18 years of age or those with any posterior decompression or osteotomy were excluded. ALIF implants in the lordotic group had 8° or 12° of inherent lordosis, whereas implants in the hyperlordotic group had 20° or 30° of lordosis. Upright standing radiographs were used to determine all radiographic parameters, including lumbar lordosis, segmental lordosis, disc space lordosis, and disc space height. Separate analyses were performed for patients who underwent single-segment fixation at L5–S1 and for the overall cohort. RESULTS A total of 204 patients were included (hyperlordotic group, 93 [45.6%]; lordotic group, 111 [54.4%]). Single-segment ALIF at L5–S1 was performed in 74 patients (hyperlordotic group, 27 [36.5%]; lordotic group, 47 [63.5%]). The overall mean ± SD age was 61.9 ± 12.3 years; 58.3% of patients (n = 119) were women. The mean number of total segments fused was 3.2 ± 2.6. Overall, 66.7% (n = 136) of patients had supine surgery and 33.3% (n = 68) had lateral surgery. Supine positioning was significantly more common in the hyperlordotic group than in the lordotic group (83.9% [78/93] vs 52.3% [58/111], p < 0.001). After adjusting for differences in surgical positioning, the change in lumbar lordosis was significantly greater for hyperlordotic versus lordotic implants (3.6° ± 7.5° vs 0.4° ± 7.5°, p = 0.048) in patients with single-level fusion. For patients receiving hyperlordotic versus lordotic implants, changes were also significantly greater for segmental lordosis (12.4° ± 7.5° vs 8.4° ± 4.9°, p = 0.03) and disc space lordosis (15.3° ± 5.4° vs 9.3° ± 5.8°, p < 0.001) after single-level fusion at L5–S1. The change in disc space height was similar for these 2 groups (p = 0.23). CONCLUSIONS Hyperlordotic implants provided a greater degree of overall lumbar lordosis restoration as well as L5–S1 segmental and disc space lordosis restoration than lordotic implants. The change in disc space height was similar. Differences in lateral and supine positioning did not affect these parameters.

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Anterior Lumbar Interbody Fusion (ALIF): Technique Video: 2-Dimensional Operative Video

Operative Neurosurgery ◽

10.1093/ons/opaa132 ◽

2020 ◽

Vol 19 (4) ◽

pp. E404-E404 ◽

Cited By ~ 1

Author(s):

Pingguo Duan ◽

Jeremy M V Guinn ◽

Brenton Pennicooke ◽

Ratnesh N Mehra ◽

Chih-Chang Chang ◽

...

Keyword(s):

Surface Area ◽

Interbody Fusion ◽

Ventral Surface ◽

Surgical Anatomy ◽

Anterior Lumbar Interbody Fusion ◽

Direct Access ◽

Lumbar Interbody Fusion ◽

Disc Space ◽

Implant Size ◽

Segmental Lordosis

Abstract This surgical video demonstrates the technique of an anterior lumbar interbody fusion (ALIF). This video demonstrates the surgical approach, technical nuances of ALIF, and pearls. The main surgical anatomy and approach-related risks are discussed. The video demonstrates the nuances of ALIF, discussing the importance of the release of the disc space to allow for height restoration and lordosis, endplate preparation to enhance arthrodesis, and choice of implant size. The incision is made via a left paramedian approach with a retroperitoneal dissection and mobilization of the vasculature for access to the disc space. The ALIF provides direct access to the ventral surface of the exposed disc, allowing for an incision of the anterior longitudinal ligament, bilateral release of the annulus fibrosus, and access to a large surface area of the vertebral endplate. This anterior access allows for the placement of implants with a greater surface area for fusion, and this facilitates restoration of segmental lordosis, disc height improvement, and foraminal height increase. We have received informed consent from this patient for the video of this case.

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Comparing Radiographic Parameters for Single-Level L5-S1 Interbody Fusion: Anterior Lumbar (ALIF) Versus Transforaminal Lumbar Interbody Fusion (TLIF)

Neurosurgery ◽

10.1093/neuros/nyz310_823 ◽

2019 ◽

Vol 66 (Supplement_1) ◽

Author(s):

Caleb S Edwards ◽

Andrew Kai-Hong Chan ◽

Dean Chou ◽

Praveen V Mummaneni

Keyword(s):

Lumbar Lordosis ◽

Interbody Fusion ◽

Pelvic Incidence ◽

Vertical Axis ◽

Central Canal ◽

Disc Height ◽

Lumbar Interbody Fusion ◽

Sagittal Vertical Axis ◽

Single Level ◽

Segmental Lordosis

Abstract INTRODUCTION The lumbosacral junction acts as a transition point between the mobile lumbar spine and the rigid pelvis. It is thereby susceptible to degenerative changes necessitating fusion at L5-S1. In this study, we compared radiographic outcomes observed from single-level anterior lumbar interbody fusion (ALIF) and transforaminal lumbar interbody fusion (TLIF) at this level. METHODS Retrospective review of single-level ALIF and TLIF with up to one level PSF at L5-S1 between May 2007 and October 2018 was undertaken. X-ray measurements were gathered for lumbar lordosis, segmental lordosis, pelvic tilt, sacral slope, pelvic incidence, pelvic incidence-lumbar lordosis mismatch, anterior/posterior disc height, and sagittal vertical axis. Computed tomography /magnetic resonance imaging was used to determine central canal area, sagittal diameter, foraminal height, and foraminal area. RESULTS A total of 47 ALIF patients and 50 TLIF patients were included. Patients averaged 53.7 ± 10.1 yr of age for ALIF and 49.4 ± 14.7 yr old for TLIF (P = .094) with significant differences (P = .0017) seen with gender as ALIF had 60.4% males and TLIF 70.0% females. Single-level ALIF led to significantly (P = .0010) more segmental lordosis (+5.75° ± 7.31°) than TLIF (+0.25° ± 6.55°), though differences in lumbar lordosis were not statistically significant (P = .52). ALIF significantly increased both anterior (+10.4 ± 4.32 mm vs +4.30 ± 3.55 mm; P < .0001) and posterior disc height (+4.33 ± 3.32 mm vs + 2.98 ± 2.07 mm; P = .043) than TLIF. Changes in sagittal vertical axis also significantly differed (P = .030) with ALIF decreasing sagittal vertical axis by 17.8 ± 26.4 mm from +60.3 mm to + 42.5 mm, and TLIF increasing by 0.95 ± 25.8 mm from 39.9 mm to 40.9 mm. Pelvic tilt, sacral slope, pelvic incidence, pelvic incidence-lumbar lordosis mismatch had no significant differences. No statistically significant differences were observed with central canal area, sagittal diameter, foraminal height or foraminal area between ALIF and TLIF. CONCLUSION At L5-S1, the ALIF approach leads to increased segmental lordosis, disc height, while also decreasing sagittal vertical axis to a significant degree than TLIF. However, these two approaches were no different with regards to pelvic parameters and measures of central canal and foraminal decompression.

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RADIOGRAPHIC ANALYSIS OF THE RESULTS OF ANTERIOR INTERNODY ARTHRODESIS ON THE SAGITTAL LUMBOPELVIC PARAMETERS

Coluna/Columna ◽

10.1590/s1808-185120201902224026 ◽

2020 ◽

Vol 19 (2) ◽

pp. 104-107

Author(s):

FELIPE DE NEGREIROS NANNI ◽

EMILIANO NEVES VIALLE ◽

MARVIN DURANTE BRUNET

Keyword(s):

Lumbar Lordosis ◽

Interbody Fusion ◽

Pelvic Tilt ◽

Pelvic Incidence ◽

Degenerative Spondylolisthesis ◽

Anterior Lumbar Interbody Fusion ◽

Sacral Slope ◽

Lumbar Interbody Fusion ◽

Pelvic Parameters ◽

Segmental Lordosis

ABSTRACT Objective The objective of this study is to analyze the radiographs of patients who underwent anterior lumbar interbody fusion (ALIF), to compare the values of the lumbopelvic measurements, and to quantify improvements in these parameters achieved through this technique. Methods The radiographs of 42 patients, all submitted to ALIF with a 12° interbody device, were evaluated from a database at a single center. The pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis, segmental lordosis, and regional lordosis angles of each patient were measured in pre- and postoperative radiographs. Results We observed a discreet change in the pelvic parameters and a marked increase in regional lordosis with a mean increase of 5.8° (p>0.001). Segmental lordosis also showed a mean increase of 2.43°. The gain in segmental lordosis was even higher in patients with degenerative spondylolisthesis and when the operated level was L5-S1. Conclusions The ALIF technique in the lumbar spine is capable of significantly increase the lordosis of a segment, whether at one or two levels. Greater improvement in the lumbopelvic parameters was observed it the procedures performed in level L5-S1 and in cases that presented spondylolisthesis.

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Feasibility of Endoscopic Transforaminal Lumbar Interbody Fusion(eTLIF) through the Posterior Paraspinal Approach: Technical Note and Preliminary Result

10.21203/rs.3.rs-28307/v2 ◽

2020 ◽

Author(s):

Hyeun-Sung Kim ◽

Harshavardhan Dilip Raorane ◽

Pang Hung Wu ◽

Dong Hwa Heo ◽

Yeon Jin Yi ◽

...

Keyword(s):

Lumbar Lordosis ◽

Interbody Fusion ◽

Plain Radiograph ◽

Transforaminal Lumbar Interbody Fusion ◽

Disc Height ◽

Lumbar Interbody Fusion ◽

Disc Space ◽

Paraspinal Approach ◽

Segmental Lordosis

Abstract Background: Implementation of endoscopic spine surgery in the management of degenerative lumbar diseases has significantly reduced the need for fusion surgeries. The performance of a MIS-TLIF using an endoscope offers some distinct advantages, such as allowing better visualization the disc space, enhanced endplate preparation and contralateral decompression. The objective of this study was to analyze the preliminary clinical and radiological outcomes of the technique of endoscopic transforaminal lumbar interbody fusion (eTLIF).Materials and Methods: eighteen consecutive patients with degenerative lumbar disease underwent eTLIF through a conventional paraspinal approach. Their clinical outcomes were evaluated with visual analog scale(VAS) leg pain score, Oswestry Disability Index(ODI) and the MacNab's criteria; radiological outcome measured with segmental lordosis, global lumbar lordosis, disc height on plain radiograph and percentage of potential fusion mass on CT scan at pre-operative, post-operative and final follow up period. Intra operative and post-operative complications were noted.Results: Mean age was 63. 71 years and Mean follow-up periods was 7.78 months. In the X-ray result, mean segmental lordosis angle(SLA) improved in pre-operative/post-operative/follow-up period 9.87±2.74 degree/ 11.79±3.74 degree/ 10.56±3.69 degree (p > 0.01); mean lumbar lordosis angle(LLA) improved 37.1±7.04 degree/ 39.2±7.13 degree/ 35.7±7.25 degree (p > 0.01). Mean preoperative disc height(DH) improved from 8.97±1.49 mm/ 12.34±1.39 mm/ 11.44±1.98 mm (p < 0.01). In the CT result, Average percentage of fusion mass was 42.61%. VAS was improved significantly, 7.67±1.13 / 3.39±1.38 / 2.5±1.34 and ODI was improved significantly, 74.9±8.03/ 34.56±8.80 / 27.76±8.64 by each preoperative / postoperative / final follow-up. In the clinical result, excellent was 5 cases and good was 13 cases. Conclusion: According to the results of this study, endoscopic TLIF was feasible procedure with an advantage of better visualization and preservation of endplate, minimal blood loss and minimal post-operative pain with early mobilization. In addition, the fusion volume as measured on post-operative CT scans, occupied 40% to 50% of disc space along with the use of 3D printed cages expected to give higher fusion rates. In conclusion, our preliminary results show that endoscopic TLIF is considered to be a viable surgical procedure with further long-term follow-up warranted.

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Expandable vs Static Cages in Transforaminal Lumbar Interbody Fusion: Radiographic Comparison of Segmental and Lumbar Sagittal Angles

Neurosurgery ◽

10.1093/neuros/nyw177 ◽

2017 ◽

Vol 81 (1) ◽

pp. 69-74 ◽

Cited By ~ 12

Author(s):

Timothy J. Yee ◽

Jacob R. Joseph ◽

Samuel W. Terman ◽

Paul Park

Keyword(s):

Retrospective Cohort ◽

Lumbar Lordosis ◽

Primary Outcome ◽

Interbody Fusion ◽

Transforaminal Lumbar Interbody Fusion ◽

Lumbar Interbody Fusion ◽

Single Level ◽

Baseline Characteristics ◽

Segmental Lordosis ◽

Expandable Cages

Abstract BACKGROUND: One criticism of transforaminal lumbar interbody fusion (TLIF) is the inability to increase segmental lordosis (SL). Expandable interbody cages are a relatively new innovation theorized to allow improvement in SL. OBJECTIVE: To compare changes in SL and lumbar lordosis (LL) after TLIF with nonexpandable vs expandable cages. METHODS: We performed a retrospective cohort study of patients who were ≥18 years old and underwent single-level TLIF between 2011 and 2014. Patients were categorized by cage type (static vs expandable). Primary outcome of interest was change in SL and LL from preoperative values to those at 1 month and 1 year postoperatively. RESULTS: A total of 89 patients were studied (48 nonexpandable group, 41 expandable group). Groups had similar baseline characteristics. For SL, median (interquartile range) improvement was 3° for nonexpandable and 2° for expandable (unadjusted, P = .09; adjusted, P = .68) at 1 month postoperatively, and 3° for nonexpandable and 1° for expandable (unadjusted, P = .41; adjusted, P = .28) at 1 year postoperatively. For LL, median improvement was 1° for nonexpandable and 2° for expandable (unadjusted, P = .20; adjusted, P = .21), and 2° for nonexpandable and 5° for expandable (unadjusted, P = .15; adjusted, P = .51) at 1 year postoperatively. After excluding parallel expandable cages, there was still no difference in SL or LL improvement at 1 month or 1 year postoperatively between static and expandable cages (both unadjusted and adjusted, P > .05). CONCLUSION: Patients undergoing single-level TLIF experienced similar improvements in SL and LL regardless of whether nonexpandable or expandable cages were placed.

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Comparison of Spinal Alignment between XLIF, TLIF, PLIF, and PLF in the Treatment of Single Level Spondylolisthesis: A Retrospective Study

Journal of the Medical Association of Thailand ◽

10.35755/jmedassocthai.2021.12.13136 ◽

2021 ◽

Vol 104 (12) ◽

pp. 1959-1965

Keyword(s):

Intervertebral Disc ◽

Spinal Fusion ◽

Lumbar Lordosis ◽

Interbody Fusion ◽

Lumbar Interbody Fusion ◽

Spinal Alignment ◽

Single Level ◽

Intervertebral Disc Height ◽

Segmental Lordosis ◽

Foraminal Height

Background: Most lumbar spinal fusion procedures are performed to increase fusion potential, correct a deformity, and decompress spinal nerve roots. Nowadays, there are several spinal fusion techniques such as extreme lateral lumbar interbody fusion (XLIF), transforaminal lumbar interbody fusion (TLIF), posterior lumbar interbody fusion (PLIF), and posterolateral fusion (PLF). However, there are no studies directly comparing their capacity to alter lumbar lordosis, segmental lordosis, intervertebral disc height, foraminal height, and the grade of slip for treating single level spondylolisthesis in Thailand. Objective: To compare which lumbar interbody technique amongst XLIF, TLIF, PLIF, and PLF, is the most effective in restoring spinal alignment in cases such as lumbar lordosis, increased segmental lordosis, increased intervertebral disc height, increased foraminal height, and a reduced slip grade in spondylolisthesis patients. Materials and Methods: The medical records and radiographs of single level spondylolisthesis patients treated in Siriraj hospital between 2002 and 2017 were retrospectively reviewed. Clinical data and radiographic parameters such as lumbar lordosis, segmental lordosis, intervertebral disc height, foraminal height, and grade of slip, including preoperative and postoperative data were collected and analyzed. An inter-observer/ intra-observer reliability test for all parameters was also performed. Results: Two hundred forty patients including 192 females and 48 males with a mean age of 60.1 years were included in the present study. There was no statistically significant difference in demographic data except in younger patients in the PLF group and those with shorter length of stays in the XLIF group. The present study results indicated that there was a statistically significant increase in lumbar lordosis, increased foraminal height, and decreased slip grade in the XLIF group when compared to other three groups as TLIF, PLIF, and PLF. Conclusion: All spinal fusion techniques could improve lumbar spinal alignment, however, XLIF is superior to other procedures, especially in lumbar lordosis, foraminal height restoration, and slip grade. Keywords: Lumbar spondylolisthesis; Extreme lateral lumbar interbody fusion; Transforaminal lumbar interbody fusion; Posterior lumbar interbody fusion; Posterolateral fusion; Lumbar lordosis

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Microendoscopy-assisted extraforaminal lumbar interbody fusion for treating single-level spondylodesis

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02313-9 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Motohide Shibayama ◽

Guang Hua Li ◽

Li Guo Zhu ◽

Zenya Ito ◽

Fujio Ito

Keyword(s):

Minimally Invasive ◽

Spinal Canal ◽

Interbody Fusion ◽

Facet Joint ◽

Clinical Results ◽

Invasive Technique ◽

Clinical Effects ◽

Lumbar Interbody Fusion ◽

Disc Space ◽

Single Level

Abstract Background Lumbar interbody fusion is a standard technique for treating degenerative lumbar disorders involving instability. Due to its invasiveness, a minimally invasive technique, extraforaminal lumbar interbody fusion (ELIF), was introduced. On surgically approaching posterolaterally, the posterior muscles and spinal canal are barely invaded. Despite its theoretical advantage, ELIF is technically demanding and has not been popularised. Therefore, we developed a microendoscopy-assisted ELIF (mELIF) technique which was designed to be safe and less invasive. Here, we aimed to report on the surgical technique and clinical results. Methods Using a posterolateral approach similar to that of lateral disc herniation surgery, a tubular retractor, 16 or 18 mm in diameter, was placed at the lateral aspect of the facet joint. The facet joint was partially excised, and the disc space was cleaned. A cage and local bone graft were inserted into the disc space. All disc-related procedures were performed under microendoscopy. The spinal canal was not invaded. Bilateral percutaneous screw-rod constructs were inserted and fixed. Results Fifty-five patients underwent the procedure. The Oswestry Disability Index and visual analogue scale scores greatly improved. Over 90% of the patients obtained excellent or good results based on Macnab’s criteria. There were neither major adverse clinical effects nor the need for additional surgery. Conclusions mELIF is minimally invasive because the spinal canal and posterior muscles are barely invaded. It produces good clinical results with fewer complications. This technique can be applied in most single-level spondylodesis cases, including those involving L5/S1 disorders.

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Trends Analysis of rhBMP2 Utilization in Single-Level Anterior Lumbar Interbody Fusion in the United States

Global Spine Journal ◽

10.1177/2192568217701119 ◽

2017 ◽

Vol 8 (2) ◽

pp. 137-141 ◽

Cited By ~ 1

Author(s):

Lifeng Lao ◽

Jeremiah R. Cohen ◽

Zorica Buser ◽

Darrel S. Brodke ◽

S. Tim Yoon ◽

...

Keyword(s):

United States ◽

Interbody Fusion ◽

Average Rate ◽

The United States ◽

Anterior Lumbar Interbody Fusion ◽

Bone Morphogenetic Protein 2 ◽

National Database ◽

Lumbar Interbody Fusion ◽

Retrospective Case ◽

Single Level

Study Design: Retrospective case study. Objective: To evaluate the trends and demographics of recombinant human bone morphogenetic protein 2 (rhBMP2) utilization in single-level anterior lumbar interbody fusion (ALIF) in the United States. Methods: Patients who underwent single-level ALIF from 2005 to 2011 were identified by searching ICD-9 diagnosis and procedure codes in the PearlDiver Patient Records Database (PearlDiver Technologies, Fort Wayne, IN), a national database of orthopedic insurance records. The year of procedure, age, gender, and region of the United States were analyzed for each patient. Results: A total of 921 patients were identified who underwent a single-level ALIF in this study. The average rate of single-level ALIF with rhBMP2 utilization increased (35%-48%) from 2005 to 2009, but sharply decreased to 16.7% in 2010 and 15.0% in 2011. The overall incidence of single-level ALIF without rhBMP2 (0.20 cases per 100 000 patients) was more than twice of the incidence of single-level ALIF with rhBMP2 (0.09 cases per 100 000 patients). The average rate of single-level ALIF with rhBMP2 utilization is highest in West (41.4%), followed by Midwest (33.3%), South (26.5%) and Northeast (22.2%). The highest incidence of single-level ALIF with rhBMP2 was observed in the group aged less than 65 years (compared with any other age groups, P < .001), with an incidence of 0.21 per 100 000 patients. Conclusions: The incidence of rhBMP2 utilization in single-level ALIF increased from 2006 to 2009, but decreased in 2010 and 2011. The Northeast region had the lowest incidence of rhBMP2 utilization. The group aged less than 65 years trended to have the higher incidence of single-level ALIF with rhBMP2 utilization.

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Feasibility of Endoscopic Transforaminal Lumbar Interbody Fusion through the Posterior Paraspinal Approach: Technical Note and Preliminary Result

10.21203/rs.3.rs-28307/v1 ◽

2020 ◽

Author(s):

Hyeun-Sung Kim ◽

Harshavardhan Dilip Raorane ◽

Pang Hung Wu ◽

Dong Hwa Heo ◽

Yeon Jin Yi ◽

...

Keyword(s):

Lumbar Lordosis ◽

Interbody Fusion ◽

Plain Radiograph ◽

Transforaminal Lumbar Interbody Fusion ◽

Disc Height ◽

Graft Material ◽

Lumbar Interbody Fusion ◽

Paraspinal Approach ◽

Segmental Lordosis

Abstract Background: The implement of endoscopic spinal surgery into degenerative spinal disease has minimized the requirement of fusion procedures. However, it is still necessary to develop endoscopic spine surgery in certain patients requiring fusion such as instability. We performed a full-endoscopic transforaminal lumbar interbody fusion(eTLIF) through a conventional paraspinal approach. The feasibility of procedure and early outcome were evaluated.Materials and Methods: eighteen consecutive patients with degenerative lumbar disease underwent eTLIF through a conventional paraspinal approach. Their clinical outcomes were evaluated with visual analog scale(VAS) leg pain score, Oswestry Disability Index(ODI) and the MacNab's criteria; radiological outcome measured with segmental lordosis, global lumbar lordosis, disc height on plain radiograph and percentage of potential fusion mass on CT scan at pre-operative, post-operative and final follow up period. intra operative and post-operative complications noted.Results: Mean age was 63. 71 years and Mean follow-up periods was 7.78 months. According to the level, L2-3 (1 case), L3-4 (4 cases), L4-5 (13 cases) and L5-S1 (2 cases). In the X-ray result, mean segmental lordosis angle(SLA) improved in pre-operative/post-operative/follow-up period 9.87±2.74 degree/ 11.79±3.74 degree/ 10.56±3.69 degree (p > 0.01); mean lumbar lordosis angle(LLA) improved 37.1±7.04 degree/ 39.2±7.13 degree/ 35.7±7.25 degree(p > 0.01). Mean preoperative disc height(DH) improved from 8.97±1.49 mm/ 12.34±1.39 mm/ 11.44±1.98 mm (p < 0.01). In the CT result, Average percentage of fusion mass was 42.61%. VAS was improved significantly, 7.67 / 3.39 / 2.5 and ODI was improved significantly, 74.9 / 34.56 / 27.76 by each preoperative / postoperative / final follow-up. In the clinical result, excellent was 5 cases and good was 13 cases. Conclusion: According to the results of this study, eTLIF was competent enough to perform as open TLIF. and good results were obtained in the form of endplate preservation, disc height restoration, minimal blood loss and post-operative pain with early mobilization. In addition, the fusion volume including the cage and the bone graft material occupies 40% to 50% of disc space is expected to give sufficient fusion by using 3D printed cages which gives the high fusion rate. In conclusion, eTLIF is considered to be a viable surgical procedure.

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