Less invasive single-rod fusion technique may be indicated in the management of NMS to minimise operative time, blood loss and wound-related complications. This retrospective 12-year cohort study (2008–2020) aims to evaluate and compare the outcomes of this technique to the current standard dual rod technique to determine their safety and efficacy. 28 patients in the single rod group (Mean age = 16.4 [SD ±4.0]) and 30 in the double rod group (Mean age = 16.3 [SD±3.5]). Indications included a minimum 2 year follow period, detailed information on the type of implant and a complete pre- and post-operative imaging and medical records. Baseline demographics, comorbidities, and surgical characteristics were collected. Outcomes assessed included the immediate post-op and final follow up angles and general complications. All outcome analysis was performed using a regression approach. Angles at final follow-up: lumbar (Difference ratio (DR)= 2.60 [95% CI 0.37 – 18.4], p=0.25), thoracic (DR= 1.08 [95% CI 0.19 – 6.28], p=0.92), thoracolumbar (major curve angle) (DR 1.35 [95% CI 0.60 – 3.06], p=0.46) and kyphosis (DR = 0.97 [0.66, 1.42] p=0.86). There was no statistically significant difference, between the two groups, for any of the above angle outcomes as well as for length of surgery, blood loss and complication outcomes. Both single and double rod instrumentation achieves satisfactory and safe deformity correction which is maintained at final follow up. A larger scale study is warranted to further assess these techniques while also conducting a cost-benefit analysis between them.
The aim of this study was test the amount of corrosion occurring at the (Ti) /cobalt chrome (CoCr) interface comparing this with Ti and Ti interfaces. This was compared with retrieved metal work visualised under a scanning electron microscope (SEM). The interface of interest is the interface between rod and the screw. We investigated corrosion seen at that interface with a CoCr rod coupled to a Ti screw versus a Ti rod coupled to a Ti screw (6 screws were used) Implants were loaded according to the ASTM F2193 – 02 Standard Specifications and Test Methods for Components Used in the Surgical Fixation of the Spinal Skeletal System. Pitting potentials were monitored using cyclic potentiodynamic polarization tests (ASTM F2129 – 08 Standard Test Method for Conducting Cyclic Potentiodynamic Polarisation Measurements) to determine corrosion susceptibility. Retrieved implants were visualised under (SEM) to confirm corrosion.Aim:
Methods:
Due to absence of fusion in guided-growth devices for EOS (growing rods, Shilla, LSZ) movement of the rods against their attachment is possible resulting in wear debris formation. It is important to understand the wear resistance of materials used in these devices under appropriate conditions. The aim of our work was to investigate wear resistance of titanium alloy Ti-6Al-4V and superelastic Nitinol. Nitinol has been used recently for correcting scoliosis and may provide a better and more gradual correction than other materials.Introduction:
Aim:
The aim of this study is to assess the safety and efficacy of a remote-operated magnetic growth rod in the treatment of 11 patients with progressive early onset scoliosis (EOS). The Growth rod technique (GR) has been a viable treatment option for progressive early onset scoliosis (EOS). However, an increased complication rate has been associated with conventional GR due to frequent surgeries required for lengthening. The safety and efficacy of a remote-operated magnetic growth rod (RO-MGR) has been previously reported in a porcine model. We are reporting the preliminary clinical results of this device which obviates the need for repeated surgeries.Purpose
Introduction
We propose a simple classification for adolescent idiopathic scoliosis (AIS) based on two components which include the curve type and shoulder level and suggest a treatment algorithm for AIS. Few Classification systems for adolescent idiopathic scoliosis (AIS) have helped in communicating, understanding and selecting a treatment for this condition; however, most of these classifications are complex and include many subtypes, making it difficult for the orthopaedic surgeon to use them in clinical practice. The variable reliability and reproducibility of these studies make recommendations and comparisons between various operative treatments a difficult task. Furthermore, none of these classifications has taken the shoulder imbalance into account, despite its importance as a clinical parameter and outcome measure.Purpose of the study
Introduction
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
We describe the results of a prospective case series to evaluate a technique of direct pars repair stabilised with a construct that consists of a pair of pedicle screws connected with a u-shaped modular link that passes beneath the spinous process. Tightening the link to the screws compresses the bone grafted pars defect providing rigid intrasegmental fixation. 20 patients aged between 9 and 21 years with a pars defect at L5 confirmed on computed tomography (CT) were included. The average age of the patients was 13.9 years. The eligible patient had Grade I or less spondylolisthesis and no evidence of intervertebral degeneration on MRI. The average duration of follow-up was 4 years. Clinical assessments for all patients was via the Oswestry disability index (ODI) and visual analogue scores (VAS). At the latest follow-up, 18 of the 20 patients had excellent clinical outcomes with a significant (p<0.001) improvement in their ODI and VAS scores with a mean post-operative ODI score of 8%. Fusion of the pars defect as assessed by CT showed fusion rates of 80%. There were no hardware complications. The strength of the construct obviates the need for post-operative immobilisation.
