Growing rods are used in the treatment of early-onset scoliosis. The aim of this technique is to achieve deformity correction while maintaining spinal growth. Gradual stiffening or spontaneous fusion of the spine can interfere with the ability to lengthen. Furthermore, diminished acquired length with serial distraction is common and needs to be evaluated and quantified. The purpose of this prospective study was to measure the forces and amount of distraction over time in patients with early-onset scoliosis treated with growing rods. Distraction forces were measured prospectively during 60 consecutive lengthening procedures in 26 patients. All patients had single submuscular rod constructs with side-to-side connectors. For every measurement, output from a transducer on a dedicated pair of distraction calipers was recorded at zero load status, and the force was then recorded at every 1 mm lengthening; length was obtained at each event and was recorded in millimeters.Introduction
Methods
There is an unresolved controversy in the published work about the effect of screws crossing the neuro-central cartilage (NCC) on spinal canal dimension in very young children and in animals. Anterior vertebral body screws with fusion can invade and damage the NCC, especially at the site of screw insertion; however, this finding has never been studied. This study is a retrospective, clinical and radiological analysis of seven consecutive children aged 1–2 years treated with anterior vertebral instrumentation and fusion by downsized rod screw systems. The mean age at time of surgery was 2 years 4 months (range 1 year 9 months to 2 years 10 months). The average follow-up period was 3 years 3 months (2 years 6 months to 4 years 5 months). 16 screws inserted anteriorely were evaluated by a follow-up CT scan. Spinal canals were divided with known anatomical landmarks into right and left hemicanals. The relation of the anterior screws to the NCC and the spinal canal dimension were studied. All clinical and radiological complications were recorded.Introduction
Methods
Surgical correction of spinal deformities is a challenge; segmental instrumentation controlling almost every level is the most recent approach. Correction of the deformity only through apical manipulation has many potential advantages, including little tissue disruption, less invasive intervention, preservation of spinal mobility, and vertebral growth. However, quantification of the amount of force needed to pull on the apex and its effect on translation, de-rotation, and overall correction of the curve needs to be studied. The purpose of this study is to determine the effect and amount of force needed to pull on the apex of a scoliotic deformity towards the midline, and the feasibility of use of this novel potential method of correction in the treatment of patients with adolescent idiopathic scoliosis (AIS). Measurements were taken from 20 patients with AIS treated between June, 2009, and January, 2010. There were 16 female and 4 male patients with an average age of 14.2 years (range 11–20); the coronal preoperative Cobb angle was 67° (42–108°), decreasing on bending to 39° (8–83°), and the apex of the deformity was between T6 and L2. All patients had proximal and distal anchors spanning two levels on each end; the anchors were connected by a concave rod to which the apical vertebra was pulled. We measured the distance between the rod and the apical vertebra and the rotation of the apical vertebrae.Introduction
Methods
The change of position of the distal pedicle screws with growing rods in relation to vertebral bodies was described as pedicle screws migration. Pedicle screws are subjected to serial distractive forces pushing them down with every distraction; additionally there is continuous growth of the vertebral bodies during the treatment period. These two factors can affect the change of position of the pedicle screws in relation to the vertebrae during the use of growing rods. To our knowledge, this finding has never been studied, confirmed, or quantified. This is a retrospective review of the radiographs and operative notes of 23 consecutive cases of early-onset scoliosis treated with single growing rods. Age at index surgery ranged from 4 years 2 months to 8 years 9 months, and the number of distractions was four to 11 per patient. Measurements were done on post-index and latest follow-up true lateral radiographs. With optimum initial position of the screws in the pedicle, we calculated the distance between the upper end plate and the pedicle screw (distance superior to the screw [SS]) and the distance between the screw and lower-end plate (distance inferior to the screw [IS]). We expressed this ratio as a percentage: SS/IS x 100%. Any increase in this percentage with time denoted a more caudal position; however, a change in the percentage of less than 10% was regarded as insignificant.Introduction
Methods
The use of thoracic pedicle screws for the treatment of adolescent idiopathic scoliosis (AIS) has gained widespread popularity. Many techniques has been described to increase the accuracy of free hand placement; however the placement of pedicle screws in the deformed spine poses unique challenges because of possible neurologic and vascular complications. We are describing a universal way of insertion of pedicle thoracic screws which has been applied in many pathologies including the deformed spine. Our technique includes exposure of the superior facet of the corresponding body to identify its lateral border border which together with the superior border of the TP denotes our entry point which is just lateral to this crossing, we make a short entry with a straight Lenke probe then continue the track with a strong ball probe to go safely through the cancellous bone of the body. This is retrospective review of radiographs and clinical notes of all the patients who underwent posterior thoracic instrumentation by pedicle screws using the same single technique by one surgeon between June 2008 and December 2009; 1653 screws in 167 consecutive patients (119 females and 48 males). There were 139 deformities, 130 scoliosis (AIS 80, Congenital 31, Neuromuscular 10 and Degenerative 9), 19 kyphosis and 18 other diagnoses (fractures 14, revision 3 and tumour 1).Introduction
Methods
Introduction: Pelvic obliquity is a constant problem in neuromuscular scoliosis. Galveston and Luque L rod techniques are well described and achieve good correction of pelvic obliquity. We describe a sacral and iliac screw construct integrated with double-rod, pedicle screws and hook system, for correction of pelvic obliquity. Method: 44 patients underwent posterior or combined anterior and posterior fusion to pelvis, for correction of neuromuscular scoliosis and pelvic obliquity. Average age at the time of surgery was 13.8 years. All patients were wheelchair-bound and nine of them were therapeutic walkers. Average follow-up was 44 months (range 24–69 months). Twenty-six patients had combined anterior and posterior surgery. All patients had posterior instrumentation to pelvis and 18 had anterior instrumentation as well. Eighteen patients had posterior instrumented fusion alone. Anterior instrumentation (when used) was Synergy and posterior instrumentation was Synergy or Colorado for all patients. Result: Average time for surgery was 5 hours and 20 minutes and average blood loss 3600 ml. The average pre-operative Cobb angle was 69° and pelvic obliquity 23°. Post-operative average Cobb angle was 29° and pelvic obliquity 7.5°. At the latest follow-up the average Cobb angle was 36° and pelvic obliquity 10°. There were three deep wound infections. Two of the sacral screws have become prominent and two patients had de-linking of the iliac screw with the rod on one side. None showed significant loss of correction. Conclusion: The sacraliliac screw construct with double rod segmental instrumentation achieved good correction of pelvic obliquity in patients with neuromuscular scoliosis. Implant related problems were infrequent
Background: The incidence of intra-spinal abnormality in congenital scoliosis is high. McMaster et al found an 18% incidence of myelographic abnormality in a series of 251 patients. Our objective was to report the MRI findings in a large series of patients with congenital scoliosis. Method: The notes, X-rays and MRI of 126 congenital scoliosis patients were reviewed to note the vertebral abnormality, curve progression, MRI findings and the presence of non-spinal congenital abnormality. These findings were then correlated to detect any association between them. Result: Forty-six patients (37%) had intra-spinal abnormalities detected on MRI. Sixty-six patients had failure of formation, 10 had failure of segmentation, 34 had mixed vertebral anomaly and 16 had congenital kyphosis or dislocation. MRI abnormality was significantly higher among patients with mixed anomaly (41%), congenital kyphosis (57%) and segmentation anomaly (40%) than those with failure of formation (29%). Presence of MRI abnormality did not correlate with curve progression or the presence of congenital abnormality affecting other organs. Conclusion: Intra-spinal abnormality in congenital scoliosis occurred in 37% cases. The incidence of such abnormality is higher in patients with congenital kyphosis, failure of segmentation and mixed vertebral anomalies.
Background: Surgical treatments described for congenital spinal deformity are i) convex growth arrest, ii) posterior or combined anterior and posterior fusion and iii) hemivertebrectomy. Posterior instrumentation is used as an adjunct to fusion, whenever possible. Anterior instrumentation for correction of congenital scoliosis has not been described. A preliminary report of the use of anterior instrumentation following hemi-vertebrectomy for correction of congenital spinal deformity is reported. Method: 15 patients with congenital scoliosis and 5 patients with congenital kyphosis underwent hemiverte-brectomy and anterior instrumentation with fusion for single-stage correction of deformity . The average age of the patients at the time of surgery was 31 months and at last follow-up 59 months. All patients had pre-operative MRI. Twelve patients had normal and 8 had abnormal MRI. The average operating time was 135 minutes and average blood loss was 462 ml. Implants used were downsize Synergy, Orion Colorado and AO Cervifix. Average sagittal Cobb angle for the scoliosis patients was 45.5° pre-operatively and 16.8° post-operatively. Average coronal Cobb angle in patients with congenital kyphosis was 61° pre-operatively and 21° postoperatively. At an average follow-up of 17 months, the correction is well maintained in all except one. This patient developed pseudarthrosis at 19 months post-operatively. This was treated with posterior instrumented fusion. There were no cases of neurologic compromise or deep wound infection. Conclusion: Because of the young age at which hemiver-tebrectomy is performed in congenital scoliosis patients, instrumentation is difficult. Posterior instrumentation has been well described in literature. Our early experience with anterior instrumentation after hemivertebrectomy shows promising results with very good correction of the deformity and no increase in complication rate.
