Anterior Slip Research Articles

37. Anatomic contributions to the stability of the L5-S1 segment under combined shear and compression: implications to isthmic/lytic spondylolisthesis

37. Anatomic contributions to the stability of the L5-S1 segment under combined shear and compression: implications to isthmic/lytic spondylolisthesis

Proposal of Treatment Strategy for Pedicle Fractures of the C2: An Analysis of 49 Cases.

Spine surgeons often confuse C2 pedicle fractures (PFs) with pars interarticularis fractures. In addition, little information is available about the characteristics and treatment strategies for C2 PFs. We sought to investigate the characteristics of C2 PFs and to propose an appropriate treatment strategy. A total of forty-nine patients with C2 PFs were included in this study. We divided these patients into unilateral and bilateral C2 PF groups. The incidence rates and characteristics of other associated C2 and C2-3 injuries, and other cervical injuries, were evaluated. In addition, treatment methods and outcomes were analyzed. Twenty-two patients had unilateral C2 PFs and twenty-seven patients had bilateral C2 PFs. Among the cases of unilateral C2 PFs, all patients had one or more other C2 fractures, and twenty patients (90.9%) had one or two C2 body fractures. Meanwhile, among the cases of bilateral C2 PF, all patients had two or more other C2 fractures and one or two C2 body fractures. In unilateral C2 PFs, three patients with C2-3 anterior slip or adjacent cervical spine (C1-3) injury underwent surgery and nineteen patients (86.4%) were treated with conservative methods. In bilateral C2 PFs, three patients with C2-3 anterior slip or SCI at C2-3 underwent surgery and twenty-four patients (88.9%) were treated with conservative methods. Our results showed that C2 PFs do not occur alone and are always accompanied by other associated C2 injuries. C2 PFs should, generally, be thought of as a more complex fracture type than hangman’s fracture or dens fracture. Despite the complex fracture characteristics, most C2 PFs can be managed with conservative treatment. However, surgical treatments should be considered if the C2 PFs are accompanied by the C2-3 anterior slip and adjacent cervical spine injury.

P134. Midterm clinical and radiological outcomes of lumbar spinal stenosis with concurrent scoliosis and/or spondylolisthesis after minimally invasive lumbar decompression surgery: Minimum 5-year follow-up

<h3>BACKGROUND CONTEXT</h3> Several studies recently have been published about the sagittal spinal alignment of lumbar spinal canal stenosis (LSS) after decompression surgery, however, little is known about these variables of LSS with concurrent degenerative spondylolisthesis (DS) and/or lumbar scoliosis (DLS). With aging of the population, spine surgeons are currently more and more confronted with a wide variety of degenerative changes of the lumbar spine. <h3>PURPOSE</h3> The purpose of this study was to investigate whether the radiological and clinical outcomes differ depend on the concomitance after minimally invasive lumbar decompression surgery. <h3>STUDY DESIGN/SETTING</h3> Retrospective analysis of prospectively collected data. <h3>PATIENT SAMPLE</h3> A total of 244 patients underwent bilateral decompression via unilateral approach using microscope or microendscope at our instituted between 2008 and 2013, and were followed up for more than 5 years postoperatively. A total of 169 patients were included in the final analysis (88 women, 81 men; mean age at surgery, 69.5±9.2years). The patients were divided into three groups: LSS group (without DS and DLS; n=91), DS group (n=59) and DLS group (n=19) <h3>OUTCOME MEASURES</h3> Clinical outcomes were evaluated with the Japanese Orthopaedic Association (JOA) scoring system (29 possible points) and visual analog scale (VAS) score for low back pain (LBP), leg pain, leg numbness and achievement of minimal clinically important difference (MCID) of VAS for low back pain (LBP) or leg pain (LP). Furthermore all spinopelvic parameters such as 1) cervical lordosis (CL): C2–7 angle (positive means lordosis); 2) cervicothoracic kyphosis (CTK): C7–T5 angle (positive means kyphosis); 3) thoracic kyphosis (TK): T5–12 angle (positive means kyphosis); 4) lumbar lordosis: T12–S1 angle (positive means lordosis); 5) C7–S1 sagittal vertical axis (SVA): distance between C-7 plumb line and posterosuperior sacrum; 6) pelvic parameters: sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI) and PI – LL were evaluated. <h3>METHODS</h3> All patients underwent bilateral decompression via a unilateral approach to decompress the central and bilateral lateral recess using a microscope or the METRx Microendoscopic Discectomy System (Medtronic Sofamor Danek, Warsaw, IN, USA). Outcomes were quantified comparatively among Simple LSS group vs DS group (with anterior slip of more than 3mm) and DLS group (with ≥ 20° coronal Cobb angle) using low back pain (LBP) /leg pain/leg numbness visual analog scale (VAS) scores, the JOA scores and variables about sagittal plane alignment before surgery, 2 years and 5 years of follow-up. <h3>RESULTS</h3> In patients coexisting DS, the clinical outcomes at 2year and 5-year after surgery were similar with that of LSS except for VAS leg numbness. In patients coexisting DLS, the VAS leg pain at 2-year after surgery was significantly higher (34.5 vs 14.5, P=0.001) and the achievement rate of the minimal clinically important difference in VAS LBP and leg pain was significantly lower than LSS group (26.3% vs 52.7%; P=0.036, 42.1% vs 72.5%; P=0.01). The reoperation rate of DS group was significantly lower than that of LSS group (3.4% vs16.5%; P=0.01), but the DLS group was comparable to the LSS group (15.8% vs 16.5%; P=0.941). Lumbar lordosis (LL), pelvic tilt and pelvic incidence-LL were significantly improved and maintained for 5 years after surgery, however, sagittal vertical axis improved at 2-year follow-up, but no significantly difference was observed at 5-year follow-up in both the DS and the DLS group. <h3>CONCLUSIONS</h3> Among patients with DS and DLS, the clinical effectiveness and radiological changes after minimally lumbar decompression surgery alone was noninferior to that of LSS without deformity. The less invasive procedure should be considered for most LSS patients. <h3>FDA DEVICE/DRUG STATUS</h3> Unavailable from authors at time of publication.

Variations in extensor tendons of the thumb –A cadaveric study

Introduction and Aims: The movements of the thumb are carried out by three muscles originating from the forearm viz., two extensors (a longus and a brevis) and an abductor. Anatomical variation has been observed in one out of every six cadavers. Among the muscles of the thumb the abductor is commonly known to show such variations. Aim of this report is to present the frequency of variations in local population. Materials and Methods: The data for the present study was collected by dissection of fifty hands (30 adult and 20fetal).Tendon slips of each of the three muscles were counted and their width was measured with a calliper. Observations: A single tendon slip of extensor pollicis longus was found in 43 (86%) hands, and in seven (14%) the tendon slip was duplicated. The extensor pollicis brevis tendon was found to have a single slip in 47 (94%) hands and in three (6%) the tendon slip was duplicated. The abductor pollicis longus tendon (APL) had a single slip in 38(76%) hands, double and triple together in 11(22%). The APL was absent in one (2%) hand. In one adult male the APL had three slips of origin; anterior slip formed a fusiform belly attached to the base of the proximal phalanx. On the left side of the same cadaver the muscle had two slips, the anterior slip divided into two, one of these ended in a fusiform belly within the thenar eminence. Conclusions: Knowledge of anatomical variations of the tendons of the thumb is essential during the surgical repair and in cases where tendon transfer is required. Multiple tendons are known to cause conditions like de Queverain's syndrome. Keywords: Thumb, Extensors, Forearm, Variations.

P45. Radiological features of slip progression in adult patients with isthmic spondylolisthesis

BACKGROUND CONTEXT Lumbar spondylolysis is generally recognized as a stress fracture of pars interarticularis occurring in childhood and adolescence. Non-union after pars fracture in the spinal motion segment may lead to isthmic spondylolisthesis. Various factors such as disc degeneration and sagittal radiological parameters contributing to slip progression in adult isthmic spondylolisthesis have been discussed. In the relationship between L5 isthmic spondylolisthesis and deformities of the sacral table, it was reported that the mechanism of vertebral slippage was different between immature and mature spine in animal studies. There are two types of isthmic spondylolisthesis which occur before and after skeletal maturity: adolescent slip with sacral deformities and adult slip without sacral deformities. However, in these two types of isthmic spondylolisthesis, there are no reports that have clarified whether there is a difference in the slip progression radiologically. PURPOSE Purpose of this study is to clarify the predictive risk factors contributing to progression of vertebral slippage in adults diagnosed with isthmic spondylolisthesis and treated conservatively. STUDY DESIGN/SETTING This is a retrospective study using 29 adult patients with isthmic spondylolisthesis. PATIENT SAMPLE Patients who were 20 to 59 years old and diagnosed with isthmic spondylolisthesis by ICD-9 and ICD-10 between 2007 and 2017 were included in this study through a Northwestern Medicine Enterprise Data Warehouse search. Patients who were diagnosed with dysplastic, traumatic, degenerative or pathologic spondylolisthesis, patients who have lumbar scoliosis, patients who have past medical history of spine surgery were excluded. OUTCOME MEASURES Slip progression and slip progression percent during follow-up. METHODS We evaluated their plain radiographs of the lumbar spine which were followed up for more than 3 years and analyzed factors affected the slip progression. RESULTS Patients’ mean age was 41.6 (± 7.9) years old. The follow-up period was 68.6 (± 20.8) months. Slip and slip% were 6.7 (± 4.1) mm, 15.5 (± 10.2) % at initial X-ray, and 10.0 (± 4.6) mm, 22.7 (± 10.6) % at final X-ray respectively. All of them progressed anterior slip during the follow-up period (P CONCLUSIONS All patients who were followed-up conservatively progressed anterior slip in this study cohort. However, the degree of their slip was not correlated with the sacral deformity or other factors described in the previous reports compared to normal group. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

The correlation between sagittal spinopelvic alignment and degree of lumbar degenerative spondylolisthesis

BackgroundRecently, several authors reported that a high pelvic incidence (PI) might be a predisposing factor to the development of anterior slip in the vertebral body in degenerative spondylolisthesis (DS). The purpose of this study was to analyze patients with DS using a multiple linear regression model, in terms of the correlation between the sagittal spinopelvic parameters and the severity of slip in each lumbar spine, including both anterior and posterior directions. MethodsStanding lateral radiographs were taken of 104 patients (59 women and 45 men) with lower back pain. The spinopelvic parameters, including PI, sacral slope (SS) and pelvic tilt (PT), angle of thoracic kyphosis (TK), angle of lumbar lordosis (LL), and sagittal vertical axis offset (SVA) were measured. Additionally, the %Slip was measured at each level between the L1 and L5. The slip direction was presented as plus to the anterior, and minus to the posterior. ResultsThe PI, SS, and/or LL correlate with L3, L4, and/or L5%Slips. The TK and SVA did not correlate with %Slip. A multiple linear regression model shows that PI and LL were significant predictors for L4 %Slip. The ROC curve demonstrated a PI cutoff value of 51.3° and an LL cutoff value of 45.0° to be predictors of anterior slip at L4. Also, our regression models revealed that PI for L3 %Slip and SS for L5 %Slip constitute significant risk factors, while determination coefficients were low. ConclusionsOur results suggest that high PI and LL are significant predictors for L4 anterior slip. At L4, the anterior slip risk-factor cutoff value was 51.3° for PI and 45.0°for LL. Additionally, our results suggest that high PI and SS could comprise risk factors for L3 anterior slip and L5 anterior slip, respectively.

29. Understanding surgeon decision-making and current surgical practice regarding the DSIC scheme and DLS treatment: a CSORN study

BACKGROUND CONTEXT Degenerative lumbar spondylolisthesis (DLS) is a spinal pathology involving the slip of one or more lumbar spinal vertebrae. It is most common in women and African-Americans above the age of 50, and usually involves the anterior slip of the fourth lumbar vertebra of up to 30% of its vertebral body width due to the more sagittally-oriented facet joints, and therefore, high force concentration at that level. Despite its worldwide prevalence of about 6%, the classification and treatment of DLS is not standardized. In 2015, Simmonds et al published the largest to-date systematic review of best available evidence and proposed a degenerative spondylolisthesis instability classification (DSIC) scheme. This classification scheme proposes that the stability of the patient's pathology be determined by a surgeon based on quantitative and qualitative clinical and radiographic parameters. PURPOSE This study aims to determine whether surgeons are following DSIC scheme treatment recommendations. It also aims to determine which radiographic and/ or clinical parameters and/ or surgeon characteristics are most influencing classification and treatment decisions. The goal of this study is to shed light on current surgeon treatment decisions and to better understand the factors most taken into account. In order for the treatment of DLS to become standardized, and therefore uniform and cost effective, we must first understand how current treatment decisions are made. STUDY DESIGN/SETTING This study used data from CSORN collected by surgeons across Canada between 2015 and 2018. Statistical analysis was used to determine which factors most influenced the classification and treatment decision of the surgeons. PATIENT SAMPLE A total of 224 patients. METHODS The patient data was collected by CSORN between 2015 and 2018 and included 224 DLS surgery cases. The data were cleaned and then analyzed using recursive feature elimination analysis, stability selection analysis, and principal component analysis to determine the correlations between the DSIC scheme parameters and the DSIC scheme grade, between the DSIC scheme parameters and the surgical treatment, and between selected parameters and the surgical treatment of DLS. Machine learning models (support vector machine and logistic regression) built using Python-based libraries were used to test the strength of the correlations found. RESULTS For the DSIC scheme classification and associated treatment, most cases of DLS were classified as being Type II (potentially unstable) (52%). However, most cases (61%) were treated with a 360° fusion regardless of their stability. In fact, only 18% of cases were classified as being Type III and thus demanding the TLIF/PLIF procedure. For Type I cases, the surgical treatment corresponding to Type I was employed 41% of the time. The use of appropriate surgical treatment was much lower for Type II (17%). For Type III, 91% of cases were treated with the recommended procedure. Dynamic translation was the parameter found to be the most correlated with the DSIC grade, with an r value of 0.475. Meyerding Grade and Disc Angle Standing were the two parameters most correlated with treatment decision-making, with respective first principal components of 0.374 and 0.332. CONCLUSIONS This study presented the demographics of DLS classification and treatment, which demonstrated that most surgeons are choosing the most extensive surgical procedure, 360° fusion, even when not indicated by the DSIC scheme. The study also found important correlations between patient and surgeon parameters and DLS classification and treatment, eg, dynamic translation influencing the classification and Meyerding Grade influencing the treatment. A larger data set would likely provide even better correlation results. Further efforts are needed to develop a new scoring algorithm that would serve to classify the stability of DLS based on the correlations found in this study. This new scoring algorithm would be extremely clinically significant as it would be more comprehensible and reproducible than the DSIC scheme and able to guide the treatment of DLS. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters: P33. The prevalence of L4-5 degenerative spondylolisthesis in females: role of spinal sagittal alignment and lumbopelvic morphology

BACKGROUND CONTEXT L4/5 degenerative spondylolisthesis (L4DS) is a common radiographic finding and predisposing factors, such as increased lumbar lordosis (LL), pelvic incidence (PI), L5 vertebral slope, and sagittal orientation of the facet joint have been reported. Among female subjects aged >65years, prevalence of L4DS was reported to be 29%, which was 1.3- to 6.4-fold higher than male subjects. However, there are few studies investigating the factors associated with the gender difference of L4DS. PURPOSE The purpose of this study is to clarify radiographic factors of L4DS with a focus on gender-specific difference in spinal sagittal alignment and lumbopelvic morphology. STUDY DESIGN/SETTING This is a prospective study. PATIENT SAMPLE Consecutive 110 patients with symptomatic lumbar canal stenosis (LCS) who underwent upright whole spine X-ray imaging, myelography, CT and MRI between 2012 and 2017 were reviewed, and those with L4/5 LCS 5% anterior slip) were excluded. A final total of 86 subjects were included, and L4DS were found in 51; 30 females (L4DSF, 70.1±8.9 years) and 21 males (L4DSM, 69.7±10.4 years), and LCS was found in 35; 12 females (LCSF, 76.8±6.4 years) and 21 males (LCSM, 67.8±8.8 years). OUTCOME MEASURES Radiographic measurement included LL, PT, L5 slope, S1 slope (SS), sagittal vertical axis (SVA), pelvic incidence (PI), disc height (DH; average of anterior and posterior disc height), L4/5 facet orientation (FOR; the angle between bilateral facet by CT), L4/5 facet osteoarthritis (FOA; grade 1 normal to grade 4 severe OA by CT), and L4/5 disc degeneration (Pfirrmann grading by MRI). METHODS In these parameters, the significant differences between LCS and L4DS in female and male were evaluated. ANOVA was used for statistical analyses and significance level was set at p RESULTS Following parameters showed significant differences; PT between gender (female 21.2±9.3, male 17.2±7.5, p=.03) and between L4DS and LCS (L4DS 20.7±8.6, LCS 16.9±8.2, p=.040), LL between L4DSF and LCSF (L4DSF 42.7±11.7, LCSF 34.5±12.0, p=.048), L5 slope between L4DS and LCS༈L4DS 16.5±7.5, LCS 13.0±9.0, p=.049; L4DSF 16.9±9.1, LCSF 8.2±11.3, p=.002), L4/5 FOR between L4DS and LCS ༈L4DS 61.7±17.9, LCS 80.2±15.0, p CONCLUSIONS L4DS showed female predominance even among symptomatic LCS patients. L4/5 FOR and FOA were associated with L4DS regardless of gender, however, influence of sagittal alignment and lumbopelvic morphology were more prevalent among female patients than male counterpart, which might explain gender difference of DS incidence. Current study substantiated previous studies using multimodal evaluations, and further studies of muscle strength, joint laxity, and other clinical factors might be necessary for understanding gender-specific incidence of DS.

Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters: P41. Agreement of degenerative spondylolisthesis definitions on standing and supine lateral radiographs in consecutive patients

BACKGROUND CONTEXT Clinical guidelines recommend standing lateral radiographs as the most appropriate imaging for detecting degenerative spondylolisthesis. However, direct comparison on definitions of spondylolisthesis on standing and supine lateral radiographs in the same patients are lacking. PURPOSE To determine the extent of agreement on commonly used definitions of degenerative spondylolisthesis on clinically obtained standing and supine lateral radiographs among the same patients. STUDY DESIGN/SETTING Cross-sectional study in new patients presenting to the Oregon Health & Science University Spine Center with chief complaint of back pain or radiculopathy. PATIENT SAMPLE Consecutive new patients from 2010 to 2016, age ≥40years, and without a history of prior spinal surgery, vertebral fracture or scoliosis greater than 30°, who were clinically evaluated for degenerative spondylolisthesis. OUTCOME MEASURES Radiographic degenerative spondylolisthesis defined as anterior displacement of ≥3 mm, ≥5 mm and ≥5%. METHODS New patients received standing AP, standing lateral and supine lateral radiographs as a clinical standard. The presence of spondylolisthesis was assessed from L1 to S1. The anterior slip distance (mm) was obtained by measuring the displacement of the posterior surface the superior vertebral body in relation to the posterior surface of the inferior vertebral body. Vertebral body width (mm) was obtained by measuring the narrowest AP diameter of the inferior vertebral body. Percent slip was calculated by dividing the anterior slip distance by the inferior vertebral body width. Kappa statistics were estimated as the measure of agreement on definitions of spondylolisthesis on the pairs of films. RESULTS This study comprised 516 patients (246 (48%) men; 270 (52%) women; mean (sd) age of 60.0 (11) years). Of these, 206 (40%) patients had 239 vertebrae with any anterior displacement of ≥3mm. Spondylolisthesis was most often observed at L4-L5 (112 vertebrae) or L5S1 (96 vertebrae). Numbers and percentages of patients classified as without spondylolisthesis on standing radiographs but with spondylolisthesis on supine radiographs for the ≥3 mm, ≥5 mm and ≥5% definitions, respectively, were 4 (1.9%), 2 (1.3%), and 3 (1.4%). Conversely, numbers and percentages of patients classified as without spondylolisthesis on supine radiographs but with spondylolisthesis on standing radiographs for ≥3 mm, ≥5 mm and ≥5% definitions, respectively, were 37 (18.0%), 46 (30.3%) and 32 (14.5%). Kappa statistics for agreement on definition of degenerative spondylolisthesis on the standing and supine lateral radiographs for ≥3 mm, ≥5 mm and ≥5% were, respectively, 0.83, 0.75 and 0.86. CONCLUSIONS From 18% to 30% of patients with radiographically detectable spondylolisthesis were misclassified as without spondylolisthesis by supine radiographs, whereas less than 2% of patients were misclassified as without spondylolisthesis on standing radiographs. Agreement between standing and supine radiographs worsened with progressively larger slip required to define spondylolisthesis. These results in a large consecutive series of new patients support clinical guidelines to use standing lateral radiographs for diagnosis of radiographic degenerative spondylolisthesis.

Change of Lumbar Ligamentum Flavum after Indirect Decompression Using Anterior Lumbar Interbody Fusion.

Study DesignRetrospective case series.PurposeThe purpose of this study was to examine changes in the ligamentum flavum thickness and remodeling of the spinal canal after anterior fusion during a 10-year follow-up.Overview of LiteratureExtreme lateral interbody fusion provides minimally invasive treatment of the lumbar spine; this anterior fusion without direct posterior decompression, so-called indirect decompression, can achieve pain relief. Anterior fusion may restore disc height, stretch the flexure of the ligamentum flavum, and increase the spinal canal diameter. However, changes in the ligamentum flavum thickness and remodeling of the spinal canal after anterior fusion during a long follow-up have not yet been reported.MethodsWe evaluated 10 patients with L4 spondylolisthesis who underwent stand-alone anterior interbody fusion using the iliac crest bone. Magnetic resonance imaging was performed 10 years after surgery. The cross-sectional area (CSA) of the dural sac and the ligamentum flavum at L1–2 to L5–S1 was calculated using a Picture Archiving and Communication System.ResultsSpinal fusion with correction loss (average, 4.75 mm anterior slip) was achieved in all patients 10 years postsurgery. The average CSAs of the dural sac and the ligamentum flavum at L1–2 to L5–S1 were 150 mm2 and 78 mm2, respectively. The average CSA of the ligamentum flavum at L4–5 (30 mm2) (fusion level) was significantly less than that at L1–2 to L3–4 or L5–S1. Although patients had an average anterior slip of 4.75 mm, the average CSA of the dural sac at L4–5 was significantly larger than at the other levels.ConclusionsSpinal stability induced a lumbar ligamentum flavum change and a sustained remodeling of the spinal canal, which may explain the long-term pain relief after indirect decompression fusion surgery.

Anterior slip phenomenon of the vertebrae after corpectomy surgery and its clinical significance

To investigate the anterior slip phenomenon of the vertebrae after corpectomy surgery and its clinical significance. The clinical data of 164 patients with cervical spondylotic myelopathy treated from January 2010 to April 2013 were retrospectively analyzed. There were 88 males and 76 females, aged from 38 to 74 years old with the mean of 56.2 years. Among them, 31 cases for C₄ corpectomy, 87 cases for C₅ corpectomy, 46 cases for C₆ corpectomy. Preoperative and postoperative distance of posterior wall of vertebral canal to the line of adjacent upper vertebral bodies anterosuperior border and lower vertebral bodies anteroinferior border was measured by CT in cervical sagittal middle layer scanning as the center, anterior slip degree of the vertebrae after operation was evaluated. The fast clustering method was used, the vertebral shift distance as variable, according to the size of the forward distance, 90 cases classified as group 1(forward greatly group), and the 74 cases classified as group 2(forwad short group). The relationships on the anterior slip of the vertebrae and cervical curvature, surgical segment were analyzed. Japanese Orthopaedic Association (JOA) scores and its improvement rate were observed before and after operation, and the relationships on the anterior slip of the vertebrae and sagittal plane diagonal diameter of spinal canal, clinical effect were analyzed. All the patients were followed up from 12 to 48 months with an average of 29.5 months. All operative vertebrae occurred anterior slip with different degree after corpectomy surgery, the maximum was 3.52 mm and minimum was 1.12 mm, with an average of (2.14±1.02) mm. According to the clustering method, the anterior slip distance with (3.07±0.21) mm classified as forward greatly group(90 cases, 54.9%) and the anterior slip distance with (1.55±0.32) mm classified as forwad short group(74 cases, 45.1%). There was no significant difference between anterior slip distance and operation segments(χ²=0.01, P=0.996). Cervical curvature index and anterior slip distance of operated vertebra had a positive correlation (r=0.724). The incidence of reduction of the diagonal diameter of cervical spinal canal in forward greatly group was higher than that of forwad short group(χ²=4.45, P=0.035). The patients with unsatisfactory efficacy appeared obvious anterior slip of the vertebrae after corpectomy than the patients with satisfactory efficacy(P<0.05). Corpectomy of the cervical spine can result in vertebral forward displacement trend, and obvious displacement may cause the secondary compression of the spinal cord.

Utility of Fusion Surgery in Patients with Degenerative Lumbar Spondylolisthesis and their Outcome

Introduction Degenerative Spondylolisthesis refers to slip of one vertebral body over the one below as a result of degenerative changes in the spine. Mild to moderate symptoms are initially treated by conservative means such as NSAIDs, epidural injections, physiotherapy, etc. But once patient suffers from severe neurological symptoms like intermittent claudication or vesico-rectal disorder due to spinal stenosis, it leads the patients to experience surgical procedures. There is no uniform agreement among surgeons about the optimal treatment. But our experience along with several high quality studies indicate that surgery provides better clinical outcome for degenerative spondylolisthesis &amp; that fusion provides better outcome than decompression alone which also results a safety profile. Material and Methods A prospective study was designed over 82 patients who had degenerative lumbar spondylolisthesis with severe neurological symptoms. The study time was from January 2003 to July 2014 in NITOR &amp; BSOH, Dhaka. We selected the patients for surgery depending on two major criteria: (1) The patient has clinically important &amp; significant pain or neurological symptoms; (2) The patient has not shown sufficient clinical improvement despite conservative care at least for 3 months. But we tried to manage those having significant osteoporosis &amp; infection through conservative treatment despite fulfilling the above criteria. Our choice of surgery was TLIF for each patient. The steps included laminectomy, insertion of cage in the disc space, interbody chips bone graft surrounding the cage &amp; posterolateral bone grafting with fixation of spine by transpedicular screws &amp; rods. Total follow up time was 11 years &amp; the minimum follow up time was 6 months. Evaluation of the patients was done comparing their pre &amp; post-operative states which included clinical evaluation, X-ray showing gradual fusion with special investigation including CT scan &amp; MRI Results 82 patients (Female- 51 &amp; male-31) with average age of 59 years (41–76 years.) having degenerative lumbar spondylolisthesis with severe neurological symptoms met the inclusion criteria. Among the patients, 57 had osteoarthritis. Total follow up time was 11 years &amp; minimum 6 months. The potential side effects included bleeding, post-operative infection, nonunion, residual deformity with spinal stenosis &amp; malposition of screws &amp; rods. The mean anterior slip was 26.1% (0–50%) prior to surgery &amp; 24.8% at the final follow up. The longer was the duration of pre-operative insult to the spinal cord or nerve root, the slower was the rate of recovery. According to these, the excellent outcome was seen in 69 patients (84% of cases), fair result was seen in 4 (5%), good in 5 (6%) &amp; poor result in 4 (5%) cases. Nonunion after surgery was observed in 3 patients. The Oswestry Disability Index Scores averages 11.1% (Range 0–62). Conclusion Though surgical procedures cannot confirm lifelong recovery of the patients with symptoms, but does ensure a better and comfortable lifestyle with potential improvement of leg symptoms in case of degenerative spondylolisthesis. Inspite successful fusion is achieved, better outcome will be ensured if any kind of activity that may overload the back is avoided.

Utility of Fusion Surgery in Patients with Degenerative Lumbar Spondylolisthesis and their Outcomes

Introduction Degenerative spondylolisthesis refers to slip of one vertebral body over the one below as a result of degenerative changes in the spine. Mild-to-moderate symptoms are initially treated by conservative means such as NSAIDs, epidural injections, physiotherapy, and so on. But once patient suffers from severe neurological symptoms such as intermittent claudication or vesicorectal disorder because of the spinal stenosis, it leads the patients to experience surgical procedures. There is no uniform agreement among surgeons about the optimal treatment. But our experience along with several high-quality studies indicate that surgery provides better clinical outcome for degenerative spondylolisthesis and that fusion provides better outcome than decompression alone. Patients and Methods A prospective study was designed over 82 patients who had degenerative lumbar spondylolisthesis with severe neurological symptoms. The study time was from January 2003 to July 2014 in NITOR and BSOH, Dhaka. We selected the patients for surgery depending on two major following criteria: (1) The patient has clinically important and significant pain or neurological symptoms. (2) The patient has not shown sufficient clinical improvement despite conservative care at least for 3 months. We tried to manage those having significant osteoporosis and infection through conservative treatment despite fulfilling the aforementioned criteria. Our choice of surgery was TLIF for each patient. The steps included laminectomy, insertion of cage in the disc space, interbody strut bone graft surrounding the cage, and posterolateral bone grafting with fixation of spine by transpedicular screws and rods. Total follow-up time was 11 years and the minimum time was 6 months. Evaluation was done comparing their pre- and postoperative states which included clinical evaluation, X-ray showing gradual fusion with special investigation including CT scan and MRI. Results A total of 82 patients (51 females and 31 males) with an average age of 59 years (range, 41–76 years.) having degenerative lumbar spondylolisthesis with severe neurological symptoms met the inclusion criteria. Among the patients, 57 had osteoarthritis. Total follow-up time was 11 years and minimum 6 months. The potential side effects included bleeding, postoperative infection, nonunion, residual deformity with spinal stenosis, and malposition of screws and rods. The mean anterior slip was 26.1% (range, 0–50%) before surgery and 24.8% at the final follow-up. The longer was the duration of preoperative insult to the spinal cord, the slower was the rate of recovery. According to these, the excellent outcome was seen in 69 patients (84% of cases), fair result was seen in 4 (5%), good in 5 (6%), and poor result in 4 (5%) cases. Nonunion after surgery was observed in three patients. Neurological symptoms improved in 1 month to 1 year. The Oswestry Disability Index Scores averages 11.1% (range, 0–62%) in at least 6 months' follow-up time. Conclusion Although surgical procedures cannot confirm lifelong recovery of the patients with symptoms, but does ensure a better and comfortable lifestyle with potential improvement of leg symptoms in case of degenerative spondylolisthesis. In spite successful fusion is achieved, better outcome will be ensured if any kind of activity that may overload the back is avoided.

Progressive restoration of spinal sagittal balance after surgical correction of lumbosacral spondylolisthesis before skeletal maturity.

Spinopelvic alignment is crucial in assessing an energy-efficient posture in both normal and disease states, such as high-displacement developmental spondylolisthesis (HDDS). The overall effect in patients with HDDS who have undergone local surgical correction of lumbosacral imbalance for the global correction of spinal balance remains unclear. This paper reports the progressive spontaneous improvement of global sagittal balance following surgical correction of lumbosacral imbalance in patients with HDDS. The records of 15 patients with HDDS who underwent surgery between 2005 and 2010 were reviewed. The treatment consisted of L4-sacrum reduction and fusion via a posterior approach, resulting in complete correction of lumbosacral kyphosis. Preoperative, 6-month postoperative, and final follow-up postoperative angular measurements were taken from full-spine lateral radiographs obtained with the patient in a standard standing position. Radiographic measurements included pelvic incidence, sacral slope, lumbar lordosis, and thoracic kyphosis. The degree of lumbosacral kyphosis was evaluated by the lumbosacral angle. Because of the small number of patients, nonparametric tests were considered for data analysis. Preoperative lumbosacral kyphosis and L-5 anterior slip were corrected by instrumentation. Transient neurological complications were noted in 5 patients. Statistical analysis showed a significant increase of thoracic kyphosis on 6-month postoperative and final follow-up radiographs (p < 0.001). A statistically significant decrease of lumbar lordosis was noted between preoperative and 6-month control radiographs (p < 0.001) and between preoperative and final follow-up radiographs (p < 0.001). Based on the authors' observations, this technique resulted in an effective reduction of L-5 anterior slip and significant reduction of lumbosacral kyphosis (from 69.8° to 105.13°). Due to complete reduction of lumbosacral kyphosis and anterior trunk displacement associated with L-5 anterior slipping, lumbar lordosis progressively decreased and thoracic kyphosis progressively increased postoperatively. Adjusting the sagittal trunk balance produced not only pelvic anteversion, but also reciprocal adjustment of lumbar lordosis and thoracic kyphosis, creating a satisfactory level of compensated global sagittal balance.

Subcapital osteotomy of the femoral neck for patients with healed slipped capital femoral epiphysis.

We report the clinical and radiological outcome of subcapital osteotomy of the femoral neck in the management of symptomatic femoroacetabular impingement (FAI) resulting from a healed slipped capital femoral epiphysis (SCFE). We believe this is only the second such study in the literature. We studied eight patients (eight hips) with symptomatic FAI after a moderate to severe healed SCFE. There were six male and two female patients, with a mean age of 17.8 years (13 to 29). All patients underwent a subcapital intracapsular osteotomy of the femoral neck after surgical hip dislocation and creation of an extended retinacular soft-tissue flap. The mean follow-up was 41 months (20 to 84). Clinical assessment included measurement of range of movement, Harris Hip Score (HHS) and Western Ontario and McMaster Universities Osteoarthritis score (WOMAC). Radiological assessment included pre- and post-operative calculation of the anterior slip angle (ASA) and lateral slip angle (LSA), the anterior offset angle (AOA) and centre head-trochanteric distance (CTD). The mean HHS at final follow-up was 92.5 (85 to 100), and the mean WOMAC scores for pain, stiffness and function were 1.3 (0 to 4), 1.4 (0 to 6) and 3.6 (0 to 19) respectively. There was a statistically significant improvement in all the radiological measurements post-operatively. The mean ASA improved from 36.6° (29° to 44°) to 10.3° (5° to 17°) (p < 0.01). The mean LSA improved from 36.6° (31° to 43°) to 15.4° (8° to 21°) (p < 0.01). The mean AOA decreased from 64.4° (50° to 78°) 32.0° (25° to 39°) post-operatively (p < 0.01). The mean CTD improved from -8.2 mm (-13.8 to +3.1) to +2.8 mm (-7.6 to +11.0) (p < 0.01). Two patients underwent further surgery for nonunion. No patient suffered avascular necrosis of the femoral head. Subcapital osteotomy for patients with a healed SCFE is more challenging than subcapital re-orientation in those with an acute or sub-acute SCFE and an open physis. An effective correction of the deformity, however, can be achieved with relief of symptoms related to impingement.

Grade three disc degeneration is a critical stage for anterior spondylolisthesis in lumbar spine

Little is known about when and how progressive spondylolisthesis occurs. In this report segmental motion related to age and disc degeneration at L4/5 disc was investigated. 637 patients with low back and/or leg pain underwent radiologic and MRI examinations simultaneously. Because 190 patients with conditions which might impede accurate measurement were excluded, 447 patients, comprising 268 men and 179 women, were included; age range, was 10-86 (mean: 53) years. Three radiologic parameters slip in neutral position (mm), sagittal translation (mm), and segmental angulation (degrees) were examined at the L4/5 segment. On T2-weighted MRI, severity of disc degeneration at L4/5 was classified by Pfirrmann's criteria, grade 1-5. Results showed stage of disc degeneration that progressed according to aging with significant differences except for between grades 4 and 5. Amount of anterior slip was small among grades 1 to 3; however, it greatly increased between grades 3 and 4 and between grades 4 and 5, suggesting that grade 3 disc degeneration has a potential risk of future progression of anterior slip. This finding may also suggest that once significant slip occurs, it will progress to the final grade. Furthermore, the grade 3 degeneration group exhibited large amounts of motion in both angulation and translation, suggesting it was the most unstable group. Our results with radiography and MRI indicate that grade 3 disc degeneration is a critical stage for the progression of lumbar spondylolisthesis at L4/5 segment.

Fetal developmental change in topographical relationship between the human lateral pterygoid muscle and buccal nerve

In adults, the lateral pterygoid muscle (LPM) is usually divided into the upper and lower heads, between which the buccal nerve passes. Using sagittal or horizontal sections of 14 fetuses and seven embryos (five specimens at approximately 20-25 weeks; five at 14-16 weeks; four at 8 weeks; seven at 6-7 weeks), we examined the topographical relationship between the LPM and the buccal nerve. In large fetuses later than 15 weeks, the upper head of the LPM was clearly discriminated from the lower head. However, the upper head was much smaller than the lower head in the smaller fetuses. Thus, in the latter, the upper head was better described as an 'anterior slip' extending from the lower head or the major muscle mass to the anterior side of the buccal nerve. The postero-anterior nerve course seemed to be determined by a branch to the temporalis muscle (i.e. the anterior deep temporal nerve). At 8 weeks, the buccal nerve passed through the roof of the small, fan-like LPM. At 6-7 weeks, the LPM anlage was embedded between the temporobuccal nerve trunk and the inferior alveolar nerve. Therefore, parts of the LPM were likely to 'leak' out of slits between the origins of the mandibular nerve branches at 7-8 weeks, and seemed to grow in size during weeks 14-20 and extend anterosuperiorly along the infratemporal surface of the prominently developing greater wing of the sphenoid bone. Consequently, the topographical relationship between the LPM and the buccal nerve appeared to 'change' during fetal development due to delayed development of the upper head.

Restoration of lordosis and disk height after single‐level transforaminal lumbar interbody fusion

To study radiographic and clinical outcomes after transforaminal lumbar interbody fusion (TLIF) in order to determine the impact of TLIF on lumbar lordosis, intervertebral height and improvement in clinical outcome measures. Forty-five patients who had undergone a single-level TLIF procedure for a single-level degenerative condition were retrospectively reviewed and their clinical histories, degree of pre- and post-operative lumbar lordosis, intervertebral height, and cage position recorded. Clinical assessment included use of modified Odom's criteria and a visual analog scale (VAS) for back and leg pain. At 21 months, the patients had gained an average of 3.6° of lumbar lordosis and 4.5 mm disc height. Change in disc height was significantly associated with an anterior cage position while lumbar lordosis was unaffected by cage position. A spondylolisthesis subgroup demonstrated 31% reduction in the magnitude of anterior slip. Less lordosis was associated with worse back and leg pain as assessed by VAS and greater disk heights were associated with higher Odom's criteria scores. Patients with persistent leg pain at final follow-up had less lumbar lordosis and intervertebral height than patients without leg pain. Intervertebral height and lumbar lordosis reconstruction are important for achieving good surgical results; guidance regarding the likely changes in lumbar lordosis and disk height after TLIF is provided by our findings.

Intimate relationship between instability and degenerative signs at L4/5 segment examined by flexion–extension radiography

Relationship between lumbar disc degeneration and segmental instability has remained controversial. Using instability factors that found close relations with symptoms in flexion-extension radiographic study, their relationship with degenerative findings was examined. More than (≥) 3mm slip in neutral position (SN), ≥3mm translation (ST), and ≥10° angulation (SA) at L4/5 segment were defined as instability factors and were applied on 447 patients who had low back and/or leg pain and satisfied inclusion criteria for accurate measurements. Radiologic findings for degeneration were disc height including three groups with different disc heights divided by mean±1 standard deviation, length of the anterior spur formation, presence of vacuum phenomenon, and endplate sclerosis. As results, group with SN factor was the oldest in age and the lowest in disc height; in contrast, group with SA was the youngest in age and the highest in disc height. The group with ST showed a mid-standing position in both age and disc height. These findings indicate that instability factors are intimately related to age and disc height. The three different disc height groups showed more anterior slip according to the progression of the disc height diminution. Presence of the apparent spur formation and/or vacuum phenomenon had an intimate relationship with the ST factor. Disc height was the most important in the examined parameters and showed an intimate relationship with age and instability factors. Although the etiology is still unknown, clinical common knowledge, that a diminution of disc height with progressive degeneration had a close relation with anterior vertebral slippage, was firstly confirmed. This study allows comprehensive understanding of segmental instability and is useful for considering surgical indications.

Evolution of a patient with Bohring–Opitz syndrome

We detailed the story from birth to the age of 5 years 9 months, of the oldest patient reported with a Bohring-Opitz syndrome with the three main diagnostic criteria: characteristic facial appearance, fixed contractures of the upper limbs and severe feeding difficulties. The facial anomalies described in our patient were microcephaly, bitemporal narrowing, "puffy" cheeks, forehead naevus flammeus, hypoplastic orbital ridges, prominent eyes, broad nasal bridge, high arched palate, buccal-alveola frenula and retrognathism. The magnetic resonance imaging (MRI) of the brain showed a hypoplastic corpus callosum and a narrowed upper cervical canal; and the cervical MRI showed a malformation of the atlas consisting in an agenesis of the anterior arch and an anterior slip of the posterior arch. We focused on her neurological and nutritional evolution. Despite the gastrostomy and a Nissen fundoplication at age 7 months, she still had developmental growth delays overall (<3rd centile). At 3 years 9 months of age, she began to put on weight quickly, which seemed to be atypical. Meanwhile she developed epilepsy, which was controlled with specific drugs. Currently, she is 5 years 9 months old and has significant psychomotor retardation, although this disease is often fatal in early childhood, due to obstructive apnea and unexplained bradycardia.