Intervertebral Disc Space Height Research Articles

170 Disc Space Height in Relation to Neural Foraminal Dimensions and Patient Characteristics: A Morphometric Analysis From L1-S1 Using Computed Tomography

INTRODUCTION: The normative relationship between lumbar intervertebral disc space height (DSH) and neuroforaminal dimensions (NFD) has yet to be defined. METHODS: Anterior, middle, and posterior DSH were measured on 350 female and 350 male patients between 18 and 35 years of age without spinal pathology. NFD were defined as sagittal anterior-to-posterior (AP) width, axial AP width, foraminal height, and area. Statistical analyses were performed to assess associations among DSH, NFD, and patient height, weight, body mass index, sex, and ethnicity. RESULTS: DSH measurements demonstrated increasing, linear trends moving caudally from L1-L2 to L5-S1, while NFD demonstrated a unimodal distribution pattern with largest NFD at L3-L4 and smallest NFD at L1-2 and L5-S1. Accounting for confounding due to height, weight, and ethnicity, male patients demonstrated larger DSH compared to female patients across all levels L1-S1 (p < .001). Asian patients demonstrated taller DSH compared to Caucasian, Hispanic, and African-American patients across all levels L1-S1 (p = .014). Zero moderate or strong correlations were observed between DSH and NFD measurements or patient characteristics for all levels L1-S1, though weight and foraminal height were weakly (r = .3) associated with increased DSH (p < .001). CONCLUSIONS: This study describes 38,500 CT-based L1-S1 disc space height and neuroforaminal measurements in young patients without spinal pathology. Among these patients, disc space height follows an increasing trend moving caudally from L1-S1, while foraminal dimensions demonstrate a unimodal distribution clustered at L3-L4. Neuroforaminal dimensions, including foraminal height, are not moderately or strongly associated with disc space height. Disc space height is influenced by sex and ethnicity but is not moderately or strongly influenced by patient height, weight, and BMI.

MRI-based synthetic CT for assessment of the bony elements of the sacroiliac joints in children

ObjectivesThe purpose of this study is to assess the equivalency of MRI-based synthetic CT (sCT) to conventional CT for sacroiliac joint bony morphology assessment in children.MethodsA prospective study was performed. Children who had (PET-)CT-scan underwent additional MRI. sCT-CT image quality was analyzed by two readers subjectively overall, semi-quantitatively in terms of cortical delineation, joint facet defects, growth plate fusion, ossified nuclei, lumbosacral transitional anomaly, and bony bridges, and quantitatively for disc space height, spinal canal width, and sacral vertebrae width and height. Cohen’s kappa and equivalence analyses with Bland–Altman plots were calculated for categorical and continuous measures respectively.ResultsTen patients were included (6 boys; aged 9–16 years; mean age 14 years). Overall sCT image quality was rated good. Semi-quantitative assessment of cortical delineation of sacroiliac joints, bony bridges, and joint facet defects on the right iliac and sacral sides showed perfect agreement. Correlation was good to excellent (kappa 0.615–1) for the presence of lumbosacral transitional anomaly, fusion of sacral growth plates, joint facet defect, and presence of ossified nuclei. sCT-CT measurements were statistically equivalent and within the equivalence margins (–1–1 mm) for intervertebral disc space height and spinal canal width.Intra- and inter-reader reliability was excellent for quantitative assessment (0.806 < ICC < 0.998). For categorical scoring, kappa ranged from substantial to excellent (0.615–1).ConclusionsCT appears to be visually equivalent to CT for the assessment of pediatric sacroiliac joints. sCT may aid in visualizing sacroiliac joints compared to conventional MRI, with the benefit that no ionizing radiation is used, especially important in children.Critical relevance statementMRI-based synthetic CT, a new technique that generates CT-like images without ionizing radiation, appears to be visually equivalent to CT for assessment of normal pediatric sacroiliac joints and can potentially assess structural damage as it clearly depicts bony cortex.Key points• MRI-based sCT is a new image technique that can generate CT-like images.• We found that sCT performs similarly to CT in displaying bony structures of pediatric sacroiliac joints.• sCT has already been clinically validated in the sacroiliac joints in adults.• sCT can potentially assess structural damage from erosions or ankylosis as it clearly depicts bony cortex.Graphical

The Comparison between Herniated and Non-Herniated Disc Levels Regarding Intervertebral Disc Space Height and Disc Degeneration, A Magnetic Resonance Study.

The main purpose of this study was to evaluate the intervertebral disc height and intervertebral disc degeneration between the normal group and the group with disc herniation at the level of the L4-L5 intervertebral disc by MRI using the Pfirrmann grading system. 385 patients were included in this study. MRI images were reevaluated and intervertebral disc heights were measured from the anterior, middle and posterior segments. Researchers divided disc pathologies into two groups. In the non-herniated group; normal or bulging ones; in the herniated group, they included those with protrusion or extrusion. 385 lumbar MRI examinations meeting the study criteria were included in study. There were 56.9% (219/385) females and 43.1% (166/385) males in the study. For the whole patients in the study group, the intervertebral disc height values at the L4-5 level were measured as 12.34 mm, 11.58 mm, and 7.60 mm in the anterior, middle, and posterior localizations, respectively. At the L4-5 level, the height of the disc distances in the herniated group was lower than in the normal group. The Pfirrman score was found to be higher in the herniated group in terms of disc degeneration compared to the normal group.

The Use of Dual Direction Expandable Titanium Cage With Biportal Endoscopic Transforaminal Lumbar Interbody Fusion: A Technical Consideration With Preliminary Results.

Expandable cage technology has emerged for lumbar interbody fusion to restore intervertebral disc space height and alignment through a narrow surgical corridor. The purpose of this study is to present the technique of biportal endoscopic transforaminal lumbar interbody fusion (TLIF) using dual direction expandable cage and provide early clinical results. We performed the biportal endoscopic TLIF using a dual direction expandable titanium cage for height restoration and a larger footprint in 10 patients. Clinical parameters including Oswestry Disability Index (ODI), visual analogue scale (VAS), and complications were retrospectively analyzed. Also, we investigated radiologic parameters using preoperative and postoperative x-ray images. We successfully inserted dual direction expandable cages during biportal endoscopic TLIF. There was no significant subsidence or collapse of the expandable cages during the 6-month follow-up period. Lumbar lordosis and disc height were significantly increased after surgery. ODI and VAS scores were significantly improved at 6 months after surgery. In this report, we describe the first use of a dual direction expandable interbody TLIF cage that expands in both width and height in biportal endoscopic TLIF surgery. Early clinical and radiographic outcomes of this TLIF technique may be favorable in early 6-month follow-up.

Comprehensive comparison of three techniques for the treatment of adjacent segment degeneration after lumbar fusion.

Adjacent segment degeneration (ASD) following lumbar fusion is technically challenging for spine surgeons. Posterolateral open fusion surgery with pedicle screw fixation is an effective way to treat symptomatic ASD with favorable clinical outcomes; however, it is associated with an increased morbidity rate. Therefore, minimally invasive spine surgery is advocated. This study was designed to compare clinical outcomes among patients with symptomatic ASD who underwent percutaneous transforaminal endoscopic discectomy (PTED) with the transforaminal approach, posterior lumbar interbody fusion (PLIF) with cortical bone trajectory screw fixation (CBT-PLIF), and PLIF with traditional trajectory screw fixation (TT-PLIF). A retrospective study was conductedon 46 patients (26 men and 20 women; average age 60.8 ± 6.78 years) with symptomatic ASD. The patients were treated with three approaches. The operation time, incision length, time to return to work, complications, and the like were compared among three groups. Intervertebral disc (IVD) space height, angular motion, and vertebral slippage were obtained to assess spine biomechanical stability following surgery. The visual analog scale (VAS) score and Oswestry disability index were evaluated at preoperation and 1-week, 3-month, and the latest follow-ups. Clinical global outcomes were also estimated using modified MacNab criteria. The operation time, incision length, intraoperative blood loss, and time to return to work for the PTED group were significantly decreased compared with those for the other two groups (P < 0.05). The radiological indicators in the CBT-PLIF group and TT-PLIF group had better biomechanical stability compared with those in the PTED groups at the latest follow-up (P < 0.05). The back pain VAS score in the CBT-PLIF group was significantly decreased compared with those in the other two groups at the latest follow-up (P < 0.05). The good-to-excellent rate was 82.35% in the PTED group, 88.89% in the CBT-PLIF group, and 85.00% in the TT-PLIF group. No serious complications were encountered. Two patients experienced dysesthesia in the PTED group; screw malposition was found in one patient in the CBT-PLIF group. One case with a dural matter tear was observed in the TT-PLIF group. All three approaches can treat patients with symptomatic ASD efficiently and safely. Functional recovery was more accelerated in the PTED group compared with the other approaches in the short term; CBT-PLIF and TT-PLIF can provide superior biomechanical stability to the lumbosacral spine following decompression compared with PTED; however, compared with TT-PLIF, CBT-PLIF can significantly reduce back pain caused by iatrogenic muscle injury and improve functional recovery. Therefore, superior clinical outcomes were achieved in the CBT-PLIF group compared with the PTED and TT-PLIF groups in the long term.

Study of single-level lumbar degenerative diseases treated by unilateral wiltse access with unilateral nail rod fixation assisted by a new automatic retraction device

ObjectiveTo evaluate the clinical efficacy of unilateral wiltse transforaminal lumbar interbody fusion (TLIF) combined with unilateral nail bar system fixation for single-level lumbar degenerative diseases with the assistance of a new automatic retraction device in a retrospective comparative study.MethodsA total of 46 patients with single-level lumbar degenerative diseases from September 2019 to December 2021 were retrospectively analyzed. Bilateral nail bar fixation with bullet-type fusion cage (ctrl group, 24 patients) and unilateral nail bar fixation on the affected side with kidney-like fusion cage (study group, 22 patients) were performed in TLIF via wiltse intermuscular approach assisted by a new automatic retraction device. The differences in intraoperative blood loss, operative time, intraoperative fluoroscopy time, postoperative drainage, bed rest, VAS score, ODI score, JOA score, serological creatine kinase (CK), the proportion of multifidus atrophy, modified Pfirrmann classification and intervertebral space height of the upper intervertebral disc were compared between the two groups based on clinical and imaging data.ResultsIntraoperative bleeding, operative time, and postoperative drainage were significantly lower in study group than ctrl group, and there were no significant differences in bed rest time and intraoperative fluoroscopy time between them. In addition, there was no statistical difference in CK between the study group and the ctrl group at 24 and 48 h postoperatively. Moreover, no statistically significant difference was found in VAS score of low back pain, VAS score of lower limb pain, ODI index, modified Pfirrmann classification of the upper intervertebral disc and intervertebral space height of the upper intervertebral disc between two groups. The atrophy ratio of multifidus muscle was significantly lower in the study group.ConclusionThe new automatic retraction device assisted unilateral TLIF surgery with wiltse approach combined with unilateral nail bar fixation is a simple, effective and easy to master surgical method for single-level lumbar degenerative diseases.

Facet joint degeneration-An initial procedure of the cervical spine degeneration.

This study aims to emphasize the initiating role of facet joint (FJ) degeneration in the process of cervical spine degeneration induced by tangential load, and we further validate it in a novel cervical spine degeneration animal model. The characteristics of cervical degeneration in patients of different ages were summarized through case collection. In the rat models, Hematoxylin-Eosin, Safranin O staining, and micro-computed tomography were used to show the histopathological changes and bone fiber structure of FJ and the height of intervertebral disc (IVD) space. The ingrowth of nociceptive sensory nerve fibers was observed by immunofluorescence staining. FJ degeneration without IVDs degeneration was more common in people with cervical spondylosis in young patients. The obvious degeneration phenotypes of the FJs preceded the IVDs at the same cervical segment in our animal model. The SP+ and CGRP+ sensory nerve fibers were observed in the articular subchondral bone of degenerated FJs and porous endplates of degenerated IVDs. The FJ degeneration may act as the major contributor to cervical spine degeneration in young people. The dysfunction of functional unit of spine, not a certain part of IVD tissue, results in the occurrence of cervical degeneration and neck pain.

Importance of the epiphyseal ring in OLIF stand-alone surgery: a biomechanical study on cadaveric spines.

To explore the function of endplate epiphyseal ring in OLIF stand-alone surgery using a biomechanical model to reduce the complications of endplate collapse and cage subsidence. In total, 24 human cadaveric lumbar function units (L1-2 and L3-4 segments) were randomly assigned to two groups. The first group was implanted with long fusion cages which engaged with both inner and outer regions of epiphyseal ring (Complete Span-Epiphyseal Ring, CSER). Those engaged with only the inner half of epiphyseal ring were the second group (Half Span-Epiphyseal Ring, HSER). Each group was divided into two subgroups [higher cage-height (HH) and normal cage-height (NH)]. Specimens were fixed in testing cups and compressed at approximately 2.5mm/s, until the first sign of structural failure. Trabecular structural damage was analyzed by Micro-CT, as well as the difference of bone volume fraction (BV/TV), trabecular thickness (Tb.Th) et al. in different regions. Endplate collapse was mainly evident in the inner region of epiphyseal ring, where trabecular injury of sub-endplate bone was most concentrated. Endplate collapse incidence was significantly higher in HSER than CSER specimens (P = 0.017). A structural failure occurred at a lower force in HSER (1.41 ± 0.34KN) compared with CSER (2.44 ± 0.59KN). HH subgroups failed at a lower average force than NH subgroups. Micro-CT results showed a more extensive trabecular fracture in HSER specimens compared to CSER specimens, especially in HH subgroup. Endplate collapse is more likely to occur with short half span cages than complete span cages, and taller cages compared with normal height cages. During OLIF surgery, we should choose cages matching intervertebral disc space height and place the cages spanning over the whole epiphyseal ring to improve support strength.

Clinical efficacy of Bone Cement-injectable Cannulated Pedicle Screw Short Segment Fixation for Lumbar Spondylolisthesis with Osteoporosise

Many clinical studies have shown a satisfactory clinical efficacy using bone cement-augmented pedicle screw in osteoporotic spine, however, few studies have involved the application of this type of screw in lumbar spondylolisthesis. This study aims to investigate the mid-term clinical outcome of bone cement-injectable cannulated pedicle screw (CICPS) in lumbar spondylolisthesis with osteoporosis. From 2011 to 2015, twenty-three patients with transforminal lumbar interbody fusion (TLIF) using CICPS for lumbar spondylolisthesis were enrolled in the study. Oswestry Disability Index (ODI) and Visual Analogue Scale (VAS) were used to evaluate faunctional recovery and physical pain; and operation time, blood loss and hospitalization time were recorded, respectively. Radiograph and computed tomography of lumbar spine was performed to assess loss of the intervertebral disc space height, fixation loosening, and the rate of bony fusion. The average follow-up time of 23 patients was 22.5 ± 10.2 months (range, 6–36 months). According to VAS and ODI scores, postoperative pain sensation and activity function were significantly improved (p < 0.05). The height of the intervertebral disc space was reduced by 0.4 ± 1.1 mm, and the bone graft fusion rate was 100%. No cases of internal fixation loosening or screw pullout was observed. CICPS using cement augmentation may suggest as a feasible surgical technique in osteoporotic patients with lumbar spondylolisthesis.

Biomechanical evaluation of single- and multi-level anterior cervical discectomy and fusion with polyetheretherketone cages: radiological and clinical outcomes.

The aim of this study was to analyse the outcomes of single- and multi-level anterior cervical discectomy and fusion (ACDF) with standalone polyetheretherketone (PEEK) cages, with particular emphasis on the risk of secondary adjacent segment disease. This retrospective study included 30 patients with single- or multi-level cervical disc herniation. Before the ACDF, and one year thereafter, the patients underwent clinical and radiological evaluation including determination of cervical pain severity with a numerical rating scale (NRS), and a survey with a Polish adaptation of the neck disability index questionnaire (NDI-PL). Biomechanical parameters of the cervical spine were determined using the Cobb method. One year after ACDF, all patients had achieved complete fusions, and 97% showed a significant reduction of pain severity. Also, a significant decrease in all NDI-PL indices was observed. A significant decrease in overall cervical spine mobility coexisted with a significant increase in the mobility of the segment above the one operated upon and a non-significant decrease in the mobility of the segment below. No statistically significant change was found in the intervertebral disc space height (IVH) above and below the operated segment, and no evidence of degeneration within the segments adjacent to the operated one was documented. One- and two-level ACDF with standalone PEEK cages provided high fusion rates. Surgical spondylosis contributed to a reduction of spinal mobility despite the hypermobility in adjacent spinal segments. No degeneration in adjacent spinal segments was documented within a year of ACDF, and the treatment seemed to improve patients' quality of life.

Short-term effects of combined pedicle/facet screw fixation plus interbody fusion through the channel-assisted muscle-splitting approach for the treatment of degenerative lumbar spine diseases in the elderly

Objective To examine the feasibility and early effects of unilateral pedicle screw fixation in combination with contralateral translaminar facet screw fixation plus interbody fusion through the channel-assisted muscle-splitting approach for the treatment of degenerative lumbar spine diseases in elderly patients. Methods A total of 82 elderly patients with degenerative lumbar spine diseases received treatment between January 2015 and June 2016.Of these patients, 25 had lumbar spinal stenosis, 42 had degenerative lumbar instability, 13 had giant lumbar disc herniation, and two had recurrent lumbar disc herniation; There were 69 cases of single segment and 13 cases of double segment lesions.Perioperative evaluation, imaging evaluation, and clinical evaluation were performed, and surgical complications were analyzed. Results The average length of incision was (2.6±0.4) cm in cases of single segment lesions and (4.4±0.5) cm in cases of two segment lesions.The mean operation time was (98.3±19.6) minutes and peri-operation blood loss was (232.2±25.8) ml.The post-operation height of the intervertebral disc space significantly increased at the last follow-up(P<0.05); the height of the intervertebral disc space was restored and well maintained with internal fixation showing no loosening, breakage or Cage shift.The post-operation lumbar coronal Cobb angle decreased(P<0.05)while the sagittal Cobb angle increased(P<0.05)at the last follow-up.There was no significant difference in the area and grade of the multifidus muscle on MRI 12 months after operation.Seventy-two patients were followed up for 12-18 months(mean=16.8 months), and there were 67 cases of intervertebral fusion(93.1%). The last follow-up showed a Japanese Orthopaedic Association(JOA)score of (25.8±1.7), which was significantly higher than the pre-operation score(10.6±1.3), with an excellence rate of 88.9%.The Oswestry Disability Index score was significantly reduced, from (50.9±21.6) at pre-operation to (9.6±4.8) at the last follow-up.There were 78 patients with primary wound healing, three cases of superficial wound necrosis, one case of dural tear, and one case of nerve root injury.No cardiovascular or cerebrovascular incident was observed during or after operation. Conclusions Combined pedicle/facet screw fixation plus interbody fusion through the channel-assisted muscle-splitting approach shows satisfactory short-term effects when used for the treatment of degenerative lumbar spine diseases in the elderly and possesses advantages such as minimal invasiveness, limited bleeding, quick recovery, high fusion rates and significantly improved clinical outcomes.However, further clinical studies are required to assess its medium-and long-term efficacy. Key words: Spinal fusion; Surgical procedures minimally invasive; Arthritis, degenerative

INTERRELATION OF SPONDYLOMETRIC PARAMETERS WITH THE OUTCOME OF SURGICAL TREATMENT OF PATIENTS WITH DEGENERATIVE DISEASES OF THE LUMBOSACRAL JUNCTION

Objective. To evaluate the relationship between the radiological and neuroimaging parameters of the spinal motion segment and the clinical outcome of surgical treatment of patients with degenerative diseases of the lumbosacral junction to clarify the indications for dynamic and rigid stabilization.Material and Methods. The study included 267 patients with degenerative diseases of the lumbosacral spine. Depending on the stabilization method, patients were divided into two groups: Group I (n = 83) with dynamic intervertebral disc (IVD) prosthesis; and Group II (n = 184) with interbody fusion and transpedicular fixation. Long-term clinical parameters and biomechanical characteristics before and after surgery were analyzed.Results. A significant nonparametric correlation of the long-term result of surgical treatment assessed by VAS and Oswestry Disability Index with radiological parameters and results of neuroimaging was revealed. It was determined that the use of artificial IVD allows achieving a minimum level of pain syndrome and good functional recovery with effective preservation of the volume of physiological movements in the operated segment and restoration of the total angle of lumbar lordosis.Conclusion. Objective neuroimaging data (grade II-IV of degeneration according to the measured diffusion coefficient) and radiological parameters (linear displacement of vertebrae not more than 4 mm, sagittal volume of movements in the spinal motion segment less than 6°, decrease in the height of intervertebral disc space no more than 2/3 of the superjacent one) make possible using total arthroplasty. It is advisable to perform interbody fusion and rigid stabilization in grade IV-V of degeneration, linear displacement of vertebrae more than 4 mm, sagittal volume of movements of at least 6°, and decrease in the interbody space height over 2/3 of the superjacent one.

ANTERIOR SURGICAL APPROACH IN RESOLVING CERVICAL MYELOPATHY RESULTING FROM A MULTISEGMENTAL DEGENERATIVE PROCESS

Progressive degenerative diseases of the cervical spine are an increasingly common cause of the development of cervical myelopathy. The analysis was performed on 67 surgically treated patients with multisegmental degenerative processes of the cervical spine. Thirty-three patients underwent surgical treatment on two levels, 25 on 3 levels and 9 on 4 levels. Muscle strength and control cervical spine X-ray were monitored pre - and postoperatively; control MRI was performed after 6 months of surgery. All the patients recovered to a higher or lower extent, and the progression of neurological deficits stopped in all of them. In 7 patients, certain swallowing problems were observed. Two patients underwent revision due to the intrusion of titanium grafts into the corpuses and front destabilization. Three patients underwent repeat surgery after one year, whereby segmental approach was expanded from two to three and from three to four levels. In 13 patients, problems with the extent of neck rotation were registered, but this did not affect their normal life activities. The finding resulting from the muscle strength monitoring of the most affected group of muscles indicates a significant improvement with respect to all levels of preoperative motor weakness. The presence of chronic pain syndrome and the development of neurological deficits in correlation with the MRI finding represent an absolute indication for surgical treatment. The anterior surgical approach not only eliminates the causes of compression of the neurovascular elements, but also provides correction of the intervertebral disc space height, correction of kyphosis and the loss of lordosis.

Relationship between annular tear and presence of Propionibacterium acnes in lumbar intervertebral disc.

Propionibacterium acnes (P. acnes) in the intervertebral disc may result in low back pain. The purpose of this study was to determine how P. acnes accesses the disc. Patients with low back pain and/or sciatica were examined using X-ray and MRI before surgery. The intervertebral disc space height was measured on X-ray image. Disc and muscle samples were obtained from 46 patients undergoing discectomy at the lumbar spine. The tear of annulus was inspected before discectomy. In the disc and muscle tissue cultures, 16S rDNA gene specific for P. acnes was examined using PCR. The discs from 11 (23.9 %) patients were identified as 16S rDNA positive, in which two patients also had 16S rDNA in their muscles. 16S rDNA gene was significantly more likely to appear in the discs with annular tear than those without tear (P < 0.05). The disc space height was significantly decreased when the disc contained P. acnes. P. acnes is significantly more likely to be present in herniated discs with an annular tear than in herniated discs without such a tear. Since in the vast majority of these cases, no P. acnes was found in control muscle samples, a true infection with P. acnes is far more likely than a contamination.

The outcomes of arthroplasty in degenerative lesions in the lumbar spine

A retrospective study. To investigate the safety and effectiveness of total intervertebral disc replacement with a Maverick prosthesis in patients with discogenic pain in the lower lumbar spine. Lumbar disc arthroplasty has been developed as an alternative to rigid interbody fusion for patients with pathology in the lower lumbar discs. According to the developers, motion preservation in the operated segment should prevent secondary pathology of the adjacent segments. From November 2007 to date, 41 patients have been operated on and 42 disc prostheses have been placed. All patients underwent surgery in the same hospital by the same surgeon. The clinical and radiological results of treatment of 35 patients were studied. The patients were examined before surgery, immediately after surgery and then in the intervals of 3-6, 6-12, 12-24, and 36-48 months. The longest follow-up was 61 months. Mean follow-up was 30 months. Patients operated on using total intervertebral disc prosthesis demonstrated a significant improvement compared to their preoperative status. A significant reduction of back and leg pain intensity was observed. The quality of life significantly improved. The intervertebral disc space height, the sagittal balance and the balance in the adjacent levels were restored and preserved after correction. The motion in the implanted segment was preserved. Total lumbar disc replacement with a Maverick prosthesis has proved to be an effective and safe technique. The clinical and radiological methods showed the significant improvement of the patients' status.

The Relationship between Increased Intervertebral Disc Height and Development of Postoperative Axial Neck Pain after Anterior Cervical Fusion

ObjectiveTo evaluate the relationship between postoperative increase in intervertebral disc space height (IVH) and posterior axial neck in cases of degenerative cervical disease treated with anterior cervical discectomy and fusion (ACDF).MethodsA total of 155 patients who underwent ACDF with more than 1 year follow up were included. Radiologically, IVH and interfacet distance (IFD) of the operated segment were measured preoperatively and postoperatively. We clinically evaluated neck and arm pains according to visual analogue scale (VAS) scores and assessed neck disability index (NDI) scores preoperatively, postoperatively, at 3 months, 6 months, and 1 year postoperatively. The relationship between radiological parameters, and clinical scores were analyzed using a regression analysis.ResultsThe mean increase in IVH was 2.62 mm, and the mean increase in IFD was 0.67 mm. The VAS scores for neck pain preoperatively, postoperatively, and at 3 months, 6 months, 1 year postoperatively were 4.46, 2.11, 2.07, 1.95, and 1.29; those for arm pain were 5.89, 3.24, 3.20, 3.03, and 2.18. The NDI scores were improved from 18.52 to 7.47. No significant relationship was observed between the radiological evaluation results regarding the increase in intervertebral height or interfacet distance and clinical changes in VAS or NDI scores.ConclusionThe increase in intervertebral space or interfacet distance by the insertion of a large graft material while performing ACDF for the treatment of degenerative cervical disease was not related with the change in VAS scores for neck and arm pains and NDI scores postoperatively and during the follow-up period.

Intervertebral Disc Height Changes After Weight Reduction in Morbidly Obese Patients and Its Effect on Quality of Life and Radicular and Low Back Pain

Prospective study in a morbidly obese population after bariatric surgery. To document the effect of significant weight reduction on intervertebral disc space height, axial back pain, radicular leg pain, and quality of life. Low back pain is a common complaint in obese patients, and weight loss is found to improve low back pain and quality of life. The mechanism by which obesity causes low back pain is not fully understood. On acute axial loading and offloading, intervertebral disc changes its height; there are no data on intervertebral disc height changes after significant weight reduction. Thirty morbidly obese adults who underwent bariatric surgery for weight reduction were enrolled in the study. Disc space height was measured before and 1 year after surgery. Visual analogue scale was used to evaluate axial and radicular pain. The 36-Item Short Form Health Survey and Moorehead-Ardelt questionnaires were used to evaluate changes in quality of life. Body weight decreased at 1 year after surgery from an average of 119.6 ± 20.7 kg to 82.9 ± 14.0 kg corresponding to an average reduction in body mass index of 42.8 ± 4.8 kg/m(2) to 29.7 ± 3.4 kg/m(2) (P < 0.001). The L4-L5 disc space height increased from 6 ± 1.3 mm, presurgery to 8 ± 1.5 mm 1 year postsurgery (P < 0.001). Both axial and radicular back pain decreased markedly after surgery (P < 0.001). Patients' Moorehead-Ardelt score significantly improved after surgery (P < 0.001). Although the 36-Item Short Form Health Survey score did not show any statistically significant improvement after surgery, the physical component of the questionnaire showed a positive trend for improvement. No correlation was noted between the amount of weight reduction and the increment in disc space height or back pain improvement. Bariatric surgery, resulting in significant weight reduction, was associated with a significant decrease in low back and radicular pain as well as a marked increase in the L4-L5 intervertebral disc height. Reduction in body weight after bariatric surgery in morbidly obese patients is associated with a significant radiographical increase in the L4-L5 disc space height as well as a significant clinical improvement in axial back and radicular leg pain.

Initial clinical outcomes of minimally invasive lateral lumbar interbody fusion in degenerative lumbar disease: a preliminary report on the experience of a single institution with 30 cases.

ObjectiveThe object of this study was to evaluate the clinical and radiological outcomes of minimally invasive lateral lumbar interbody fusion.MethodsThis study included 30 patients who underwent minimally invasive lateral lumbar interbody fusion at our hospital between May 2011 and February 2012 for the following diagnoses: degenerative disc disease, adjacent-segment degeneration, degenerative spondylolisthesis and lumbar degenerative scoliosis. Pain assessment was reported from 0 to 10 using a subjective visual analog scale (VAS) upon admission and at every follow-up day. Lumbar X-rays were obtained in the standing position upon admission and the 1st and 5th postoperative day, and at every follow-up day after the operation. The heights of the intervertebral disc space and neural foramen were measured using an electronic caliper with the PACS software. The surgical outcome was assessed as excellent, good, fair or poor using the Odom scale at the last follow-up.ResultsThe mean VAS for low back pain were 4.93±1.47 on admission and 2.01±1.35 at last follow-up, respectively, and for leg pain, the scores were 4.87±2.16 on admission and 1.58±1.52 at last follow-up. The mean height of intervertebral disc space increased by 34% (7.93±2.33 preoperatively, and 11.09±4.33 immediately after surgery, p<0.01). The mean height of neural foramen also increased by 6.4% without any statistical significance (19.17±2.84 preoperatively, and 20.49±4.50 immediately after the surgery). Minimally invasive lateral lumbar interbody fusion was successful in 27 patients (90%) at last follow-up. Surgical complications were reported as transient postoperative thigh sensory changes (5 patients, 16.7%), transient psoas muscle weakness (3 patients, 10%), cage migration (2 patients, 6.7%), lumbar plexus injury (1 patient, 3.3%), and pain aggravation (1 patient, 3.3%).ConclusionThe minimally invasive lateral lumbar interbody fusion is a safe and effective procedure for treating degenerative lumbar disease with good outcomes and moderate complications. Further follow-up is necessary to establish its safety and efficacy.

Anterior Lumbar Interbody Implants: Importance of the Interdevice Distance

Object. The implantation of interbody fusion cages allows for the restoration of disc height and the enlargement of the neuroforaminal space. The purpose of this study was to compare the extent of subsidence occurring after conventional cage placement compared to a novel wider cage placement technique. Methods. This study is a retrospective evaluation of radiographs of patients who underwent stand-alone single level anterior lumbar interbody fusion with lordotic titanium cages and rhBMP-2. Fifty-three patients were evaluated: 39 patients had wide cage placement (6 mm interdevice distance) and 14 had narrow cage placement (2 mm interdevice distance). Anterior and posterior intervertebral disc space heights were measured post-operatively and at follow-up imaging. Results. The decrease in anterior intervertebral disc space height was 2.05 mm versus 3.92 mm (P < .005) and 1.08 mm versus 3.06 mm in posterior disc space height for the wide cage placement and the narrow cage placement respectively. The proportion of patients with subsidence greater than 2 mm was 41.0% in the wide cage patients and 85.7% for the narrow cage patients (P < .005). Conclusions. The wider cage placement significantly reduced the amount of subsidence while allowing for a greater exposed surface area for interbody fusion.

Anatomic basis of anterior and posterior instrumentation of the spine: morphometric study

A morphometric study of the linear and angular parameters of the spinal vertebra was conducted by computerized tomographic scans and comparison with previous studies in literature. Detailed knowledge of the spinal vertebral morphometry is important for proper instrumentation. The morphologic measurements vary among races. Morphometric studies have been conducted in white populations. This study aims to suggest dimensions for anterior and posterior spinal implants and to improve the instrumentation techniques. The vertebral pedicles, bodies and intervertebral disc spaces of the subaxial cervical, thoracic and lumbar spine were studied in 48 healthy individuals by computerized tomographic scan methods. The following parameters were studied: pedicle length, pedicle width, transverse pedicle angle (TPA), sagittal pedicle angle, anterior corpus height, posterior corpus height, anterior disc height, middle disc height and posterior disc height. Our results were slightly different compared to previous studies. Individual differences were found in the same subgroups. The transverse pedicle diameter was largest at L5 (14.95 mm) and smallest at C3 (5.1 mm). The pedicle was longest at L5 (19.9 mm) and shortest at T10 (15.7).The TPA was largest at C3 (47.6 degrees ) and smallest at T6 (11.3 degrees ). The vertebral body was largest at L5 (34.9 mm) and smallest at C3 and C5 (15.6 mm). The vertebral body width was largest at L5 (46.6 mm) and smallest at C4 (22 mm). The intervertebral disc space height was largest at L2-3 (10 mm) and smallest at T1-2 (2.85 mm). There were no significant differences between the left and right sides. In our morphometric study of the spinal vertebrae, we found differences compared to a number of previous morphometric studies performed mainly on a white population. Also, we documented the individual morphometric differences of the same parameters in the same subgroups. These results emphasize the importance of preoperative computed tomography and conventional radiography of each patient in planning a surgical procedure and selecting the appropriate size of the instruments, thus avoiding possible postoperative complication related to implants.