Aims. Spinal deformity surgery carries the risk of neurological injury. Neurophysiological monitoring allows early identification of intraoperative cord injury which enables early intervention resulting in a better prognosis. Although multimodal monitoring is the ideal, resource constraints make surgeon-directed intraoperative transcranial motor evoked potential (TcMEP) monitoring a useful compromise. Our experience using surgeon-directed TcMEP is presented in terms of viability, safety, and efficacy. Methods. We carried out a retrospective review of a single surgeon’s prospectively maintained database of cases in which TcMEP monitoring had been used between 2010 and 2017. The upper limbs were used as the control. A true alert was recorded when there was a 50% or more loss of amplitude from the lower limbs with maintained upper limb signals. Patients with true alerts were identified and their case history analyzed. Results. Of the 299 cases reviewed, 279 (93.3%) had acceptable traces throughout and awoke with normal clinical neurological function. No patient with normal traces had a postoperative clinical neurological deficit. True alerts occurred in 20 cases (6.7%). The diagnoses of the alert group included nine cases of adolescent idiopathic scoliosis (AIS) (45%) and six of congenital scoliosis (30%). The incidence of deterioration based on diagnosis was 9/153 (6%) for AIS, 6/30 (20%) for congenital scoliosis, and 2/16 (12.5%) for spinal tuberculosis. Deterioration was much more common in congenital scoliosis than in AIS (p = 0.020). Overall, 65% of alerts occurred during rod instrumentation: 15% occurred during decompression of the internal apex in vertebral column resection surgery. Four alert cases (20%) awoke with clinically detectable neurological compromise. Conclusion. Surgeon-directed TcMEP monitoring has a 100% negative predictive value and allows early identification of physiological cord distress, thereby enabling immediate intervention. In resource constrained environments, surgeon-directed TcMEP is a viable and effective method of intraoperative
We report our experience of the monitoring of spinal somatosensory evoked potentials in 60 patients with neuromuscular scoliosis. In 15 cases a significant change occurred in the trace when a sublaminar wire was tightened. There were no postoperative neurological deficits attributable to the surgery.
Since 1981, during operations for spinal deformity, we have routinely used electrophysiological monitoring of the spinal cord by the epidural measurement of somatosensory evoked potentials (SEPs) in response to stimulation of the posterior tibial nerve. We present the results in 1168 consecutive cases. Decreases in SEP amplitude of more than 50% occurred in 119 patients, of whom 32 had clinically detectable neurological changes postoperatively. In 35 cases the SEP amplitude was rapidly restored, either spontaneously or by repositioning of the recording electrode; they had no postoperative neurological changes. One patient had delayed onset of postoperative symptoms referrable to nerve root lesions without evidence of spinal cord involvement, but there were no false negative cases of intra-operative spinal cord damage. In 52 patients persistent, significant, SEP changes were noted without clinically detectable neurological sequelae. None of the many cases which showed falls in SEP amplitude of less than 50% experienced neurological problems. Neuromuscular scoliosis, the use of sublaminar wires, the magnitude of SEP decrement, and a limited or absent intra-operative recovery of SEP amplitude were identified as factors which increased the risk of postoperative neurological deficit.
Segmental vessel ligation during anterior spinal surgery has been associated with paraplegia. However, the incidence and risk factors for this devastating complication are debated. We reviewed 346 consecutive paediatric and adolescent patients ranging in age from three to 18 years who underwent surgery for anterior spinal deformity through a thoracic or thoracoabdominal approach, during which 2651 segmental vessels were ligated. There were 173 patients with idiopathic scoliosis, 80 with congenital scoliosis or kyphosis, 43 with neuromuscular and 31 with syndromic scoliosis, 12 with a scoliosis associated with intraspinal abnormalities, and seven with a kyphosis. There was only one neurological complication, which occurred in a patient with a 127° congenital thoracic scoliosis due to a unilateral unsegmented bar with contralateral hemivertebrae at the same level associated with a thoracic diastematomyelia and tethered cord. This patient was operated upon early in the series, when intra-operative
Introduction
Introduction Transcranial motor evoked potentials are routinely used at The Children’s Hospital at Westmead to
The April 2012 Children’s orthopaedics Roundup. 360 . looks at osteonecrosis of the femoral head and surgery for dysplasia, femoral head blood flow during surgery, femoroacetabular impingement and sport in adolescence, the Drehmann sign, a predictive algorithm for septic arthritis, ACL reconstruction and arthrofibrosis in children,
Introduction. Evidence suggests that intra-operative
Abstract. Objective. Spinal cord surgery is a technically challenging endeavour with potentially devastating complications for patients and surgeons. Intra-operative neurophysiological monitoring(IONM), or
Percutaneous vertebroplasty (PVP), where vertebral bodies are injected with polymethylmethacrylate (PMMA) cement, is used to treat various spinal lesions. Although the complication rate for PVP is low, thermal damage caused by the exothermic curing of PMMA has been implicated. This study was to measure the temperatures reached during PVP as PMMA cures as well as assessing the cement volume effect and inter cement differences. Validating
Introduction Vertebroplasty (VP), where vertebral bodies are injected with polymethylmethacrylate (PMMA) cement, is used to treat various spinal lesions. More recently VP has been used for augmenting osteoporotic vertebral bodies that have fractured or are at risk of fracture. Although the complication rate for VP is low, thermal damage caused by the exothermic curing of PMMA has been implicated. The aim of this series of experiments was to measure the temperatures reached during VP using a sheep model. The cement volume effect and inter cement differences were assessed.
Background: To review the results of
Purpose of the study. Two patients with very severe thoracolumbar Scheuermann's kyphosis who developed spontaneous bony fusion across the apex of the deformity are presented and their treatment, as well as surgical outcome is discussed. Summary of Background Data. Considerable debate exists regarding the pathogenesis, natural history and treatment of Scheuermann's kyphosis. Surgical correction is indicated in the presence of severe kyphosis which carries the risk of neurological complications, persistent back pain and significant cosmetic deformity. Methods. We reviewed the medical notes and radiographs of 2 adolescent patients with severe thoracolumbar Scheuermann's kyphosis who developed spontaneous posterior and anteroposterior fusion across the apex of the deformity. Results. Patient 1. A male patient aged 17 years and 11 months underwent kyphosis correction when the deformity measured 115o and only corrected to 100o on supine hyperextension radiograph against the bolster; he had a small associated scoliosis. The surgery involved a combined single-stage anterior and posterior spinal arthrodesis T4-L3 with the use of posterior pedicle hook/screw/rod instrumentation and autologous rib graft. The anterior longitudinal ligament was ossified from T10 to L1 with bridging osteophytes extending circumferentially from T11 to T12 at the apex of kyphosis and displacing the major vessels anteriorly. The intervertebral discs from T9 to T12 were very stenotic and immobile. The osteophytes were excised both on the convexity and concavity of the associated thoracolumbar scoliosis. The anterior longitudinal ligament was released and complete discectomies back to the posterior longitudinal ligament were performed from T7 to L1. During the posterior exposure, the spine was found to be spontaneously fused across the apex of the kyphosis from T9 to L1. There were no congenital vertebral anomalies. Extensive posterior apical closing wedge osteotomies were performed from T7 to T12. The fused facets and ossified ligamentum flavum were excised and the spine was mobilised at completion of the anterior and posterior osteotomies. The kyphosis was corrected using a cantilever maneuver from proximal to distal under
To determine whether neurophysiological electrical pedicle testing (EPT) is a useful aid in the detection of malpostioned pedicle screw tracts. EPT data from 246 screws in 32 spinal operations on 32 patients over a 5 year period (2009–2014) were recorded and analysed. In addition to physical palpation, a ball-tipped electrode delivered stimuli and the output was recorded by evoked electromyogram (EMG). When breach threshold values were recorded, the surgeon rechecked the tract for breaches and responded appropriately. In addition, standard motor evoked potential (MEP) and sensory evoked potential(SEP)
A combined anterior and posterior surgical approach
is generally recommended in the treatment of severe congenital kyphosis,
despite the fact that the anterior vascular supply of the spine
and viscera are at risk during exposure. The aim of this study was
to determine whether the surgical treatment of severe congenital thoracolumbar
kyphosis through a single posterior approach is feasible, safe and
effective. We reviewed the records of ten patients with a mean age of 11.1
years (5.4 to 14.1) who underwent surgery either by pedicle subtraction
osteotomy or by vertebral column resection with instrumented fusion
through a single posterior approach. The mean kyphotic deformity improved from 59.9° (45° to 110°)
pre-operatively to 17.5° (3° to 40°) at a mean follow-up of 47.0
months (29 to 85).
Comparison of efficacy of multi-modality
Introduction:. Scheuermann's kyphosis is a fixed round back deformity characterised by wedged vertebrae seen on radiograph. It is known patients presented with a negative sagittal balance before operation. Few studies investigated the outcome after operation, especially the change in the lumbar hyperlordosis. Aim:. To investigate the change in sagittal profile after correction surgery. Method:. This is a retrospective review of cases from 2001 to 2012. Our centre uses a posterior, four rod cantilever reduction technique for all Scheuermann's Kyphosis correction. 36 cases are identified. They include 24 males and 12 females with an average age of 20 and follow up of 27 months. First 8 cases used the stainless steel hybrid implants. The remaining 28 had titanium all pedicle screw system. All had intra-operative
To establish the current practice of
Aim:. Recent guidelines have been published by the Association of Neurophysiological Scientists / British Society for Clinical Neurophysiology (ANS/BSCN) regarding the use of intra-operative neurophysiological monitoring (IOM) during spinal deformity procedures. We present our unit's experience with IOM and the compliance with national guidelines. Method:. All patients undergoing intra-operative
Background:. Spinal deformity surgery carries the risk of loss of neurological function which may be permanent. Although the overall the incidence is low it is much higher in complex congenital deformities or those with pre-existing myelopathy. Intra-operative