Kinematics analyses of the spine have been recognized as an effective method for functional analysis of the spine. CT is suitable for obtaining bony geometry of the vertebrae but radiation is a clinical concern. MRI is noninvasive but it is difficult to detect bone edges especially at endplates and processes where soft tissues attach. Kinematics analyses require tracking of solid bodies; therefore, bony geometry is not always necessary for kinematics analysis of the spine. This study aimed to develop a reliable and robust method for kinematics analysis of the spine using an innovative MRI-based 3D bone-marrow model. This IRB-approved study recruited 17 patients undergoing lumbar decompression surgery to treat a single-level symptomatic herniation as part of a clinical trial for a new dynamic stabilization device. T1 & T2 sagittal MRI scans were acquired as part of the pre-operative evaluation in three positions: supine and with the shoulders rotated 45° to the left and right to induce torsion of the lumbar spine. 3D bone-marrow models of L5 and S1 at the neutral and rotated positions were created by selecting a threshold level of the bone-marrow intensity at bone-marrow/bone interface. Validated 3D-3D registration techniques were used to track movements of L5 and S1. Segmental movements at L5/S1 during torsion were calculated.Introduction
Materials and Methods
Study design: We conducted a prospective cohort study of 448 patients with a variety of spinal metastases. To compare the predictive value of the Tokuhashi scoring system (T12) and its revised edition (T15) for life expectancy both in the entire study group as well as in the various primary tumor subgroups. In 1990 Tokuhashi and coworkers formulated a one point-addition-type prognostic scoring system with a total sum of 12 points for preoperative prediction of life expectancy as an adjunct in selecting appropriate treatment. Because the site of the primary tumor influences ultimate survival, the scoring system was revised in 2005 to a total sum of 15 points based on the origin of the primary tumor.Objective
Summary of background data
To identify risk factors for the presence of distal adding-on in Lenke 1A scoliosis and compare different treatment strategies. Distal adding-on is often accompanied by unsatisfactory clinical outcome and high risk of reoperation. However, very few studies have focused on distal adding-on and its attendant risk factors and optimal treatment strategies remain controversial.Objective
Summary of Background Data
How translation of different parts of spine responds to selective thoracic fusion has not been well investigated. Furthermore, how posterior pedicle-screw-only constructs affect spontaneous lumbar curve correction (SLCC) remains unknown. In a retrospective study, we aimed to investigate the balance change after selective thoracic fusion in Lenke 1C type adolescent idiopathic scoliosis (AIS) treated with posterior pedicle-screw-only constructs. All AIS cases, surgically treated between 2002 and 2008 in our institute, were reviewed. Inclusion criteria were: patients with Lenke 1C scoliosis treated with posterior pedicle-screw-only constructs; the lowest instrumented vertebra (LIV) ended at L1 level or above; and a minimum 2-year radiographic follow-up. Standing anteroposterior (AP) and lateral digital radiographs from different timepoints (preoperative, immediately postoperative, 3 months postoperative, and final follow-up) were reviewed. In each standing AP radiograph, centre sacral vertical line (CSVL) was drawn first, followed by measurement of the translation (deviation from the CSVL) of some key vertebrae, such as the LIV, LIV+1 (the first vertebra below LIV), LIV+2 (the second vertebra below LIV), LIV+3 (the third vertebra below LIV), lumbar apical vertebra, thoracic apical vertebra, and T1. Additionally, the Cobb angles of major thoracic and lumbar curve were measured at different timepoints, and the correction rate was calculated. Furthermore, clinical photos of patients' back appearance were taken preoperatively and postoperatively.Introduction
Methods
Distal adding-on is often accompanied by unsatisfactory clinical outcome and high risk of reoperation. However, very few studies have focused on distal adding-on and its attendant risk factors, and optimum treatment strategies remain controversial. In a retrospective study, we aimed to identify risk factors for the presence of distal adding-on in Lenke 1A scoliosis and to compare different treatment strategies. Data for all surgically treated patients with adolescent idiopathic scoliosis (AIS) were retrieved from one institutional database. Inclusion criteria included: patients with Lenke 1A scoliosis treated with posterior pedicle screw-only constructs; and a minimum 1-year radiographic follow-up. Distal adding-on was defined as a progressive increase in the number of vertebrae included distally within the primary curve combined with either an increase of more than 5 mm in deviation of the first vertebra below instrumentation from the centre sacral vertical line (CSVL), or an increase of more than 5° in the angulation of the first disc below the instrumentation at 1 year follow-up. Wilcoxon rank-sum test, Fisher's exact test, and Spearman's correlation test were used to identify the risk factors for adding-on. A multiple logistic regression model was built to identify independent predictive factors. Risk factors included: age at surgery; preoperative Cobb angle; correction rate; the gap difference of stable vertebra (SV) and lowest instrumented vertebra (LIV), neutral vertebra (NC) and LIV, and end vertebra (EV) and LIV (gap difference means, for example, if SV is at L2 and LIV is at Th12, then the difference of SV-LIV is 2); and the preoperative deviation of LIV+1 (the first vertebra below the instrumentation) from the CSVL (the vertical line that bisects proximal sacrum). Five methods for determining LIV were compared in both the adding-on group and the no adding-on group.Introduction
Methods
Overall of all petients who underwent surgery, 71% had improved pain control, 53% regained mobility, 64% improved by at least one Frankel grade or maintained normal neurology and 39% regained normal urinary sphincter function. While 18% were bed bound preoperatively, only 5% were still in bed postoperatively. Perioperative mortality rate was 5.8% and morbidity was 21%. The median survival for the cohort was 352 days (11.7 months). The radical surgery group had a median survival of 438 days and the palliative group 112 days (P = 0.003).
The purpose of our study is to analyze retrospectively our patients, who had received conservative treatment or either posterior or combined approach.
The diagnosed was based on clinical examination, cultures, bone histology, X-rays, bone scan and MRI with gadolinium. The location of the infection was in 13 (8%) patients the cervical spine, in 62 (38%) the thorachic, in 10 (6%) the thoracolumbar junction and in 78 (48%) the lumbo-sacral spine. In 95 cases, concomitant diseases were present. In 67 (41%) patients was not able to detect any microorganism. From the remaining patients, 53 (33%) were infected by staph.aureus and 22 (13%) by mycob tuberculosis. The patients according to the treatment provided, were divided in three groups:
Group A: 70 patients, which had conservative treatment with antibiotics and bracing. Group B: 56 patients, which, sustained posterior decompression alone Group C: 37 patients, which had anterior debridemant and posterior decompression and stabilizations or anterior stabilization.
The group A patients had not neurological symptoms. In group B, 11 had altered neurology and the operation was beneficial for 5 of them (45.5%), 4 remained unchanged and in 2 was deteriorate. In group C, 11 patients had altered neurology, from which 9 (81.8%) were improved and 2 remained unchanged. The in-hospital complications were: 2 pulmonary embolism, 2 post operative haematomas, 1 persistent anaimia, 1 diafragm paralysis, 2 atelectasia and 1 cerebral thrombosis. In addition 3 patients had residual psoas abscess, 2 pancreas abscess, 1 cerebelum abscess and 3 lung infection. The in-hospital mortality was 3 patients, other 17 patients died during the follow up
The conservative management in selected patients is effective up to 89%. From the operations performed the decompression alone had unacceptable high re-operation rate and also, it wasn’t so beneficial regarding the neurological improvement. If it is combined with anterior reconstruction and posterior stabilization provides better results.
