L4-5 Transforaminal Lumbar Interbody Fusion Research Articles

Lumbar Apex Position as an Independent Risk Factor for Adjacent Segment Diseases in Patients Undergoing Short-level Transforaminal Lumbar Interbody Fusion.

Retrospective study. To investigate whether lumbar apex position had an impact on the development of adjacent segment disease (ASD) following transforaminal lumbar interbody fusion (TLIF). Previous studies have demonstrated that solely concentrating on lumbar lordosis value is not suitable and neglecting the significance of lumbar apex can lead to mechanical complications. However, the relationship between lumbar apex and ASD is still not well understood. In this retrospective study, 234 consecutive patients who underwent L3-5 or L4-5 TLIF for degenerative diseases were reviewed. The study evaluated the associations between sagittal parameters and pelvic incidence (PI). Patients were labeled "matched" when lumbar apex position aligned with the theoretical target, and "mismatched" when it did not. Multivariate analysis was applied to find the independent risk factors of ASD. Additionally, a focused sub-analysis was performed based on the lumbar apex position (ideal match, cranial from ideal, and caudal from ideal). After an average follow-up period of 70.6 months, 68 cases were identified as having ASD. Postoperatively, 64.7% (44 out of 68) of the patients with ASD exhibited a mismatched lumbar apex, compared to 41% (68 out of 166) of those without ASD (p < 0.001). PI correlated significantly with proximal lordosis (PL) and lordosis distribution index (LDI), but not with distal lordosis (DL). Multivariate analysis identified age, L3-5 fusion, postoperative DL, and postoperative mismatched lumbar apex as independent risk factors of ASD. Upon the sub-analysis, it was discovered that there were unique compensatory strategies in the cranial and caudal groups, with notable variations in postoperative DL, PL, and LDI among three groups (all p value<0.05). Lumbar apex position significantly influenced the risk of ASD. To restore the lumbar apex to its ideal position, a proper value and distribution of DL should be attained.

Oblique anterior column realignment with a mini-open posterior column osteotomy for minimally invasive adult spinal deformity correction: illustrative case.

Adult spinal deformity (ASD) occurs from progressive anterior column collapse due to disc space desiccation, compression fractures, and autofusion across disc spaces. Anterior column realignment (ACR) is increasingly recognized as a powerful tool to address ASD by progressively lengthening the anterior column through the release of the anterior longitudinal ligament during lateral interbody approaches. Here, we describe the application of minimally invasive ACR through an oblique antepsoas corridor for deformity correction in a patient with adult degenerative scoliosis and significant sagittal imbalance. A 65-year-old female with a prior history of L4-5 transforaminal lumbar interbody fusion and morbid obesity presented with refractory, severe low-back and lower-extremity pain. Preoperative radiographs showed significant sagittal imbalance. Computed tomography showed a healed L4-5 fusion and a vacuum disc at L3-4 and L5-S1, whereas magnetic resonance imaging was notable for central canal stenosis at L3-4. The patient was treated with a first-stage L5-S1 lateral anterior lumbar interbody fusion with oblique L2-4 ACR. The second-stage posterior approach consisted of a robot-guided minimally invasive T10-ilium posterior instrumented fusion with a mini-open L2-4 posterior column osteotomy (PCO). Postoperative radiographs showed the restoration of her sagittal balance. There were no complications. Oblique ACR is a powerful minimally invasive tool for sagittal plane correction. When combined with a mini-open PCO, substantial segmental lordosis can be achieved while eliminating the need for multilevel PCO or invasive three-column osteotomies.

Prediction Model and Risk Factor Analysis of Adjacent Segment Disease After L4-5 Transforaminal Lumbar Interbody Fusion Through Preoperative Radiographic Features.

A retrospective study. To investigate the risk of adjacent segment disease (ASD) after L4-5 transforaminal lumbar interbody fusion (TLIF) in patients diagnosed with lumbar spinal stenosis (LSS), a prediction model for ASD is established and validated. A retrospective study was carried out on a sample of 290 patients who underwent L4-5 TLIF at Zhongda Hospital, Southeast University, from January 2015 to January 2021. The study collected baseline data and preoperative radiographic features of L3-4 and L5-S1. The determination of the outcome variable was based on X-ray results spanning over 24months and JOA scores. Multivariate logistic regression was used to identify the risk factors in constructing a nomogram. Independent risk factors for L3-4 degeneration after TLIF included osteoarthritis of L3-4 facet joints, L3-4 foraminal stenosis, L4 upper endplate osteochondritis, L3-4 local lordosis angle, and L3-4 spinal stenosis. Independent risk factors for L5-S1 degeneration after TLIF included osteoarthritis of L5-S1 facet joints, L5-S1 intervertebral disc degeneration, L5-S1 spinal stenosis, L5-S1 coronal imbalance, and S1 upper endplate osteochondritis. A predictive model was developed. The AUC for the prediction models at L3-4 and L5-S1 were .945 and .956. The calibration curve demonstrated good consistency between the predicted and actual probabilities. The DCA curve indicated the clinical benefit and practical value of this predictive model. This study established nomograms for postoperative degeneration at L3-4 and L5-S1 based on selected preoperative radiographic features. These models provide a valuable auxiliary decision-making system for clinicians and aid in early surgical decisions.

Adjacent Segment Vertebral Body Bone Density Changes as Measured By Hounsfield Units After Lumbar Spine Fusion.

We sought to evaluate Hounsfield units (HU) at the adjacent segment after single-level transforaminal lumbar interbody fusion (TLIF) with preoperative and postoperative computed tomography scans. We performed a retrospective study on a series of patients who underwent L4-5 TLIF, from 2007 to 2017, by 3 spine surgeons at our institution. One-hundred and forty-three total patients were identified, and 41 patients with minimum 1-year follow-up met inclusion criteria. HU values were measured on preoperative and postoperative computed tomography at the adjacent L3 segment and at L1 as a control arm. Lumbar lordosis, pelvic tilt, pelvic incidence, sacral slope, and sagittal vertical axis were also collected preoperatively and postoperatively. Mean preoperative HU value at L3 did not differ from the postoperative value (134.11 ± 47.14 mg/cm3 vs. 141.21 ± 55.14 mg/cm3, P= 0.34). Similarly, the mean preoperative HU value at the L1 control level region of interest did not differ from the postoperative value (150.17 ± 53.91 mg/cm3 vs. 145.78 ± 58.34 mg/cm3, P= 0.634). The interrater reliability of HU measurements was satisfactory with a resulting intraclass correlation coefficient of 0.76. As measured by HU, we did not observe a change in bone density or other signs of adjacent segment disease at the L3 vertebral body 12 months after L4-5 TLIF. Spinopelvic parameters were not shown to be correlated with HU changes.

Multicenter assessment of outcomes and complications associated with transforaminal versus anterior lumbar interbody fusion for fractional curve correction.

Few studies have compared fractional curve correction after long fusion between transforaminal lumbar interbody fusion (TLIF) and anterior lumbar interbody fusion (ALIF) for adult symptomatic thoracolumbar/lumbar scoliosis (ASLS). The objective of this study was to compare fractional correction, health-related quality of life (HRQL), and complications associated with L4-S1 TLIF versus those of ALIF as an operative treatment of ASLS. The authors retrospectively analyzed a prospective multicenter adult spinal deformity database. Inclusion required a fractional curve ≥ 10°, a thoracolumbar/lumbar curve ≥ 30°, index TLIF or ALIF performed at L4-5 and/or L5-S1, and a minimum 2-year follow-up. TLIF and ALIF patients were propensity matched according to the number and type of interbody fusion at L4-S1. Of 135 potentially eligible consecutive patients, 106 (78.5%) achieved the minimum 2-year follow-up (mean ± SD age 60.6 ± 9.3 years, 85% women, 44.3% underwent TLIF, and 55.7% underwent ALIF). Index operations had mean ± SD 12.2 ± 3.6 posterior levels, 86.6% of patients underwent iliac fixation, 67.0% underwent TLIF/ALIF at L4-5, and 84.0% underwent TLIF/ALIF at L5-S1. Compared with TLIF patients, ALIF patients had greater cage height (10.9 ± 2.1 mm for TLIF patients vs 14.5 ± 3.0 mm for ALIF patients, p = 0.001) and lordosis (6.3° ± 1.6° for TLIF patients vs 17.0° ± 9.9° for ALIF patients, p = 0.001) and longer operative duration (6.7 ± 1.5 hours for TLIF patients vs 8.9 ± 2.5 hours for ALIF patients, p < 0.001). In all patients, final alignment improved significantly in terms of the fractional curve (20.2° ± 7.0° to 6.9° ± 5.2°), maximum coronal Cobb angle (55.0° ± 14.8° to 23.9° ± 14.3°), C7 sagittal vertical axis (5.1 ± 6.2 cm to 2.3 ± 5.4 cm), pelvic tilt (24.6° ± 8.1° to 22.7° ± 9.5°), and lumbar lordosis (32.3° ± 18.8° to 51.4° ± 14.1°) (all p < 0.05). Matched analysis demonstrated comparable fractional correction (-13.6° ± 6.7° for TLIF patients vs -13.6° ± 8.1° for ALIF patients, p = 0.982). In all patients, final HRQL improved significantly in terms of Oswestry Disability Index (ODI) score (42.4 ± 16.3 to 24.2 ± 19.9), physical component summary (PCS) score of the 36-item Short-Form Health Survey (32.6 ± 9.3 to 41.3 ± 11.7), and Scoliosis Research Society-22r score (2.9 ± 0.6 to 3.7 ± 0.7) (all p < 0.05). Matched analysis demonstrated worse ODI (30.9 ± 21.1 for TLIF patients vs 17.9 ± 17.1 for ALIF patients, p = 0.017) and PCS (38.3 ± 12.0 for TLIF patients vs 45.3 ± 10.1 for ALIF patients, p = 0.020) scores for TLIF patients at the last follow-up (despite no differences in these parameters at baseline). The rates of total complications were similar (76.6% for TLIF patients vs 71.2% for ALIF patients, p = 0.530), but significantly more TLIF patients had rod fracture (28.6% of TLIF patients vs 7.1% of ALIF patients, p = 0.036). Multiple regression analysis demonstrated that a 1-mm increase in L4-5 TLIF cage height led to a 2.2° reduction in L4 coronal tilt (p = 0.011), and a 1° increase in L5-S1 ALIF cage lordosis led to a 0.4° increase in L5-S1 segmental lordosis (p = 0.045). Operative treatment of ASLS with L4-S1 TLIF versus ALIF demonstrated comparable mean fractional curve correction (66.7% vs 64.8%), despite use of significantly larger, more lordotic ALIF cages. TLIF cage height had a significant impact on leveling L4 coronal tilt, whereas ALIF cage lordosis had a significant impact on restoration of lumbosacral lordosis. The advantages of TLIF may include reduced operative duration and hospitalization; however, associated HRQL was inferior and more rod fractures were detected in the TLIF patients included in this study.

Pseudohypoxic brain swelling and secondary hydrocephalus with pseudomeningocele after lumbar surgery: a case report

Background Postoperative intracranial complications are rare in spine surgery not including cranial procedures. We describe an uncommon case of pseudohypoxic brain swelling (PHBS) and secondary hydrocephalus after transforaminal lumbar interbody fusion (TLIF) presenting as impaired consciousness and repeated seizures. Case presentation A 65-year-old man underwent L4-5 TLIF for lumbar spondylolisthesis and began experiencing generalized seizures immediately postoperatively. Computed tomography (CT) revealed diffuse cerebral edema-like hypoxic ischemic encephalopathy. He was transported to our hospital, at which time epidural drainage was halted and anti-edema therapy was commenced. His impaired consciousness improved. However, he suffered secondary hydrocephalus due to continuous bleeding from a dural defect and spinal epidural fluid collection 3 months later. Following the completion of dural repair and insertion of a ventriculoperitoneal shunt, his neurologic symptoms and neuroimaging findings improved significantly. Conclusions PHBS can be considered in patients with unexpected neurological deterioration following lumbar spine surgery even with the absence of documented durotomy. This might be due to postoperative intracranial hypotension-associated venous congestion, and to be distinguished from the more common postoperative cerebral ischemic events–caused by arterial or venous occlusions–or anesthetics complications.

Revision Surgery for Adjacent Segment Degeneration After Fusion for Lumbar Spondylolisthesis: Is there a Correlation with Roussouly Type?

Retrospective study. The aim of this study was to investigate whether there is an association between revision surgery rates for adjacent segment degeneration (ASD) and Roussouly type after L4-5 transforaminal lumbar interbody fusion (TLIF) for spondylolisthesis. Revision surgery for ASD is known to occur after spinal fusion; however, it is unclear whether rates of ASD are associated with certain Roussouly types. Patients who underwent L4-5 TLIF for spondylolisthesis at the University of California San Francisco from January 2006 to December 2016 with minimum 2-year follow-up were retrospectively analyzed by Roussouly type. Revision surgery for ASD was noted and correlated by Roussouly type. Spinopelvic parameters were also measured for correlation. A value of P < 0.05 was significant. There were 174 patients who met inclusion criteria, (59 males and 115 females). The average age was 62.3 (25-80) years. A total of 132 patients had grade I spondylolisthesis, and 42 had grade II. Mean follow-up was 45.2 months (24-497). A total of 22 patients (12.6%) underwent revision surgery for ASD after L4-5 TLIF. When classified by Roussouly type, revision surgery rates for ASD were: 1, 14.3%; 2, 22.6%; 3, 4.9%; and 4, 15.6% (P = 0.013). Type 3 spines with normal PI-LL (8.85° ± 6.83°) had the lowest revision surgery rate (4.9%), and type 2 spines with PI-LL mismatch (11.06° ± 8.81°) had the highest revision surgery rate (22.6%), a four-fold difference (P = 0.013). The PI-LL mismatch did not change significantly in each type postoperatively (P > 0.05). We found that there may be a correlation between Roussouly type and revision surgery for ASD after L4-5 TLIF for spondylolisthesis, with type 2 spines having the highest rate. Spinopelvic parameters may also correlate with revision surgery for ASD after L4-5 TLIF.Level of Evidence: 4.

3-Dimensionally Printed Biomimetic Surgical Simulation-Operative Technique of a Transforaminal Lumbar Interbody Fusion: 2-Dimensional Operative Video.

We present a surgical video highlighting the technical demonstration and microsurgical anatomy of an L4-5 transforaminal lumbar interbody fusion utilizing a combination of thermoplastic polymers and 3-dimensional printing technology to create a biomimetic lumbar spine surgical simulator. The posterior elements of L4-5 and the inferior portion of L3 are exposed in their entirety, including the transverse processes in order to identify the appropriate landmarks for pedicle screw insertion. The interspinous ligament of L4-5 is removed, and an interlaminar spreader is used to distract the facet joint. An inferior L4 facetectomy is performed for local autograft harvesting. The L4 and L5 pedicles are skeletonized to completely open the foramen in order to ensure that the exiting nerve root will not be compromised during cage insertion. The ligamentum flavum is then removed, exposing the common thecal sac and L5 traversing root. The L4 exiting nerve root is then identified, completing Kambin's triangle and location of the disc space. The disc is incised, and a combination of punches and curettes are used to completely remove the disc. After an interbody trial is used to assess the proper cage size, the cage is packed with graft and inserted into the midline of the disc space. Pedicle screws are then placed using an anatomic freehand technique, and intraoperative fluoroscopy is performed in order to evaluate the instrumentation and interbody position. If a contralateral decompression is required, a facet-sparing technique is performed in order to preserve bony surface for the fusion. Patient consent was not required for this simulation video.

Sensorineural Deafness After Spine Surgery: Case Series and Literature Review

Sudden sensorineural hearing loss (SNHL) after nonotologic surgery is unusual, with most occurrences reported in patients having cardiopulmonary bypass. Reports of SNHL after nonotologic noncardiac surgery are rare, particularly after spine surgery. In patients undergoing subarachnoid anesthesia or intradural surgery, loss of cerebrospinal fluid pressure can result in hearing loss and cranial nerve palsy. A 70-year-old male patient had ankylosing spondylitis with an Anderson lesion T11-12 with diabetes mellitus, hypertension, and American Spinal Injury Association Impairment Scale-A neurology. He underwent posterior stabilization of T10-L1 and developed a profound, painless, left-sided hearing deficit shortly afterward. An otorhinolaryngology consultation confirmed SNHL. An 82-year-old male reported claudication with L4-5 LCS and type 2 diabetes mellitus. Post L4-5 transforaminal lumbar interbody fusion, he complained of hearing loss in his left ear, confirmed by an otolaryngologist. A 72-year-old diabetic male had tuberculous spondylodiskitis of D2-3 with an epidural abscess. An emergent decompression and stabilization C7-D5 bone grafting at D2-3 was done. In the early postoperative period, the patient complained of marked hearing impairment on the right side. Audiometry indicated SNHL in his right ear. A course of intravenous corticosteroids was instituted in the first and second patients for severe hearing loss. Steroids were not given to the third patient in view of his Pott spine. No improvement in hearing impairment occurred until the latest follow-up in all patients. Sudden-onset hearing loss post spine surgery is disastrous with multiple etiologies and remains poorly understood. Timely evaluation by an otolaryngologist and audiologist is recommended. The role of corticosteroids in treating SNHL is still unclear.

Adjacent Intervertebral Disk Height Decrease Phenomenon After Single-Level Transforaminal Lumbar Interbody Fusion of the Lumbar Spine

The increase of intradiskal pressure on the upper segment resulting from intervertebral distraction after lumbar intervertebral fusion decreases intervertebral height and aggravates degeneration. However, the incidence rate and risk factors of the adjacent intervertebral disk height decrease phenomenon have not been studied. The purpose of this study was to identify the incidence rate and risk factors of the adjacent intervertebral disk height decrease phenomenon after single-level transforaminal lumbar interbody fusion (TLIF) of the lumbar spine. A retrospection of 68 patients who underwent L4-5 TLIF. Patient age, sex, and body mass index were collected. Lumbar lordosis, facet sagittalization, Pfirrmann classification, L4-5 distraction height, and L3-4 reduction height were evaluated by radiologic image. The patients were divided into 2 groups based on whether their L3-4 intervertebral height decreased. Forty of 68 patients (58.8%) had L3-4 intervertebral height decrease. The patients' mean age was 62.05 ± 10.90 years in the L3-4 intervertebral height decrease positive (IHDP) group, significantly higher than the 56.14±12.06 years in the L3-4 intervertebral height decrease negative (IHDN) group (P= 0.039). The mean facet sagittalization angle in the IHDP group was 67.5°±20.36°, significantly larger than the 55.43° ± 14.97° in the IHDN group (P= 0.010). The preoperative lumbar lordosis was significantly higher in the IHDP group (P=0.049). No significant effects of other factors on L3-4 height decrease were observed (P > 0.05). Distraction of the L4-5 intervertebral space by cage insertion leads to a reduced height on the adjacent L3-4 segment in some patients. In addition, the decrease in L3-4 intervertebral height resulting from L4-5 distraction was correlated with age, preoperative lumbar lordosis, and facet joint sagittalization.

The compression of L5 nerve root, single or double sites?-radiographic graded signs, intra-operative detect technique and clinical outcomes.

The L5 nerve root could be compressed at both L4-5 and L5-S1 regions. If L5 nerve root has confirmed compression at L4-5 level and questionable compression at L5-S1 foramina, performing both surgeries at L4-5 and L5-S1 levels may induce unnecessary extra surgery on L5-S1; however, ignoring foraminal stenosis of L5/S1 may require re-exploration. Two hundred seventeen patients with L5 nerve root compressed at L4-5 lateral access were performed with L4-5 decompression and interbody fusion. Lee et al. grade classification was used to assess the foraminal stenosis of L5-S1 preoperatively. Nerve root probe was designed and used to detect if there were foraminal stenosis at L5-S1 level that compressing the exiting L5 nerve root. Visual analog scale (VAS) of low back pain, leg pain and Oswestry Disability Index (ODI) were used to assess clinical outcomes. For all of 217 patients who underwent L4-5 surgery, L5-S1 foramina were preoperatively assessed as: grade 0: 125 cases, grade 1: 58 cases, grade 2: 23 cases, and grade 3: 11 cases. After intra-operative L5 nerve root detection, 11/11 patients with grade 3 radiographic foraminal stenosis, 6/23 (26.1%) with grade 2 and 2/58 (3.4%) who had grade 1 underwent L4-5 and L5-S1 transforaminal lumbar interbody fusion (TLIF), the others received only L4-5 TLIF. Compared to pre-operative baseline data, both L4-5 TLIF and L4-5 and L5-S1 TLIF groups had significant decreased VAS of low back pain and leg pain, and ODI at 3 and 24 months after operation. We suggested that our novel nerve root probe combined with pre-operative radiographic grade may be helpful to surgeons to identify the single or double compression of L5 nerve root and make a more precise surgical strategy to improve surgical outcome than the method depended on pre-operative radiographic grade alone.

Hydrodissection of Wiltse's Plane to Facilitate Exposure During Minimally Invasive Transforaminal Lumbar Interbody Fusion.

Traditional posterior lumbar approaches in a transforaminal lumbar interbody fusion (TLIF) require subperiosteal dissection of bilateral paraspinal muscles to provide adequate exposure. This may traumatize the multifidus muscle and its afferent innervations leading to postoperative paraspinal muscle atrophy. Minimizing such intraoperative trauma has been identified as an important factor in the reduction of postoperative lumbar pain. An approach via a blunt dissection through Wiltse’s plane, which lies between the longissimus and multifidus muscles, may minimize postoperative pain. Definition of this plane may be facilitated by local injection of 1% lidocaine within the plane itself, as well as in the musculature defining its borders.In this paper, we demonstrate this technique with a 55-year-old female patient who presented with left-sided radicular leg pain in an L5 distribution. Wiltse plane hydrodissection was utilized in performing an L4-5 TLIF. Ultrasound images of the patient’s sub-fascial musculature were obtained pre- and posthydrodissection to assess the elucidation of this plane through this technique. Intraoperative images were obtained following dissection of Wiltse’s plane to further illustrate the facilitation of exposure of Wiltse’s plane through hydrodissection. Postoperatively the patient did well citing a complete resolution of her radicular pain. She did not require intravenous (IV) pain medication, as her postoperative pain was well controlled with oral pain medication. She was mobilized on post-op day one, and discharged home on post-op day two with minimal back pain.Our initial experience supports the feasibility, safety, and effectiveness of hydrodissection of Wiltse’s plane to facilitate exposure during a minimally invasive TLIF and thereby reducing postoperative pain.

An Innovative Use of Cortoss Bone Cement to Stabilize a Nonunion after Interbody Fusion.

A 65-year-old male originally had surgery for spondylolisthesis at L5-S1 in 2008 and then went on to have an L4-5 transforaminal lumbar interbody fusion (TLIF) with pedicle screw fixation from L4 to S1 and interbody graft in 2010. Despite having two surgical procedures, he continued with intractable back pain and was told he had a failed lumbar fusion. When he was evaluated with a computerized tomography (CT) scan from April 2015, it demonstrated an erosive nonunion of the L4-5 interbody fusion without incorporation of the polyetheretherketone (PEEK) cage. In an attempt to perform a minimally invasive stabilization of the L4-5 nonunion, he underwent a percutaneous lateral foraminal approach with an injection of Cortoss® cement (Stryker®, Malvern, PA) into the L4-5 interspace and around the graft. The objective was to stabilize the nonunion, resulting in intermediate relief of pain.