Aims. Severe spinal deformity in growing patients often requires surgical management. We describe the incidence of spinal deformity surgery in a National Health Service. Methods. Descriptive study of prospectively collected data. Clinical data of all patients undergoing surgery for spinal deformity between 2005 and 2018 was collected, compared to the demographics of the national population, and analyzed by underlying aetiology. Results. Our cohort comprised 2,205 patients; this represents an incidence of 14 per 100,000 individuals among the national population aged between zero and 18 years. There was an increase in mean annual incidence of spinal deformity surgery across the study period from 9.6 (7.2 to 11.7) per 100,000 individuals in 2005 to 2008, to 17.9 (16.1 to 21.5) per 100,000 individuals in 2015 to 2018 (p = 0.001). The most common cause of spinal deformity was idiopathic scoliosis accounting for 56.7% of patients. There was an increase in mean incidence of surgery for adolescent idiopathic scoliosis (AIS) (from 4.4 (3.1 to 5.9) to 9.8 (9.1 to 10.8) per 100,000 individuals; p < 0.001), juvenile idiopathic scoliosis (JIS) (from 0.2 (0.1 to 0.4) to one (0.5 to 1.3) per 100,000 individuals; p = 0.009), syndromic scoliosis (from 0.7 (0.3 to 0.9) to 1.7 (1.2 to 2.4) per 100,000 individuals; p = 0.044), Scheuermann’s kyphosis (SK) (from 0.2 (0 to 0.7) to 1.2 (1.1 to 1.3) per 100,000 individuals; p = 0.001), and scoliosis with intraspinal abnormalities (from 0.04 (0 to 0.08) to 0.6 (0.5 to 0.8) per 100,000 individuals; p = 0.008) across the study period. There was an increase in mean number of posterior spinal fusions performed each year from mean 84.5 (51 to 108) in 2005 to 2008 to 182.5 (170 to 210) in 2015 to 2018 (p < 0.001) and a reduction in mean number of growing rod procedures from 45.5 (18 to 66) in 2005 to 2008 to 16.8 (11 to 24) in 2015 to 2018 (p = 0.046). Conclusion. The incidence of patients with spinal deformity undergoing surgery increased from 2005 to 2018. This was largely attributable to an increase in surgical patients with adolescent idiopathic scoliosis. Paediatric spinal deformity was increasingly treated by posterior spinal fusion, coinciding with a decrease in the number of growing rod procedures. These results can be used to plan paediatric spinal deformity services but also evaluate preventative strategies and research, including population screening

Objective: Determine the incidence of abnormal somatosensory evoked potentials (SSEP) in patients with ‘at risk’ spinal cords undergoing anterior spinal deformity surgery. Design: A retrospective chart and SSEP trace review of cases between 1982–2001. Subjects: Patients undergoing elective anterior spinal deformity surgery were included. Excluded were those with inadequate SSEP monitoring or no pre-operative MRI scan. Outcome measures: Paraparesis due to cord ischaemia based on an abnormal SSEP trace, i. e. > 50% decrease in SSEP baseline amplitude +/− > 10% increase in latency. 1. . Results: Partial data was available for 1982–1990, thus analysis was based on cases between 1990–2001.871 patients underwent elective anterior spinal deformity surgery, 11% were ‘at risk cords’; 2% demonstrated intraoperative SSEP changes. Post operative paraparesis ws found in 0.6%. Intra-operative changes were significantly more common in ‘at risk cords’ (chi-squared test = 30.3, df = 2; p< 0.005). No statistical difference in the incidence of paraparesis in normal cords vs ‘at risk’ cords. Conclusions: Post operative neurological deficit is rare in anterior spinal deformity surgery. Significant SSEP changes do occur with ligation of segmental vessels, implying cord ischaemia. Therefore, for the ‘at risk cord’, these patients should be considered for spinal cord monitoring and temporary clamping of segmental vessels prior to their division

Objective: Recent reports have suggested a low incidence of neurological complications following anterior deformity surgery; however in patients with co-existing intra-spinal anomalies no quantification of this risk has been made. Also, whether SSEP monitoring and soft clamping of segmental vessels prior to their division is necessary for these anterior procedures is controversial. The aims of this study were to determine the incidence of significant SSEP changes in patients undergoing anterior spinal deformity surgery; to ascertain whether the ‘at risk’ cord was more likely to demonstrate significant intraoperative SSEP changes and what proportion of these changes yielded post operative neurological deficit. Design: Retrospective analysis of operative notes and somatosensory evoked potential (SSEP) traces of patients who underwent anterior spinal deformity surgery between 1990–2001. Subjects: All patients who underwent anterior spinal deformity surgery between 1990–2001, who had complete data sets (preoperative MRI scan, patient and procedural documentation and intraoperative SSEP traces) were included in the study. Outcome measures: All post operative neurological deficits and significant SSEP changes were noted, whether or not patients had a ‘cord at risk’. Results: In total, 871 patients had elective anterior spinal deformity surgery. Preoperative MRI revealed 95 patients (11%) demonstrated intraspinal anomalies on MRI but of these only 27 showed abnormal pre-operative SSEP i.e. cord at risk (CAR). Seventeen (2% of total) of this group developed abnormal intraoperative SSEP responses and ten (1.3%) occurred in the normal group. The incidence of post-operative paraparesis for the whole series was 0.6% (n=5): four in the CAR group, one in the normal cord group. Sensitivity of SSEPs in detecting potential neurological deficit was 100%; specificity 98.6%, positive predictive value 29.4% and negative predictive value 100%. Significant intraoperative SSEP changes occurred more frequently in the CAR group and were more likely to have post operative paraparesis. Conclusions: SSEP monitoring is a sensitive and specific test, which in experienced hands yields no false positive results. Spinal cord monitoring and soft clamping of segmental vessels should be performed in patients with CAR undergoing anterior spinal deformity surgery to minimise the risk of post operative paraparesis

Intrathecal morphine (IM) is a common adjunct in paediatric spinal deformity surgery. We previously demonstrated with idiopathic scoliosis it provides safe and effective analgesia in the immediate postoperative period. This study represents our 25 year experience with IM in all diagnostic groups. Our prospective Pediatric Orthopaedic Spine Database (1993–2018) was reviewed to identify all patients undergoing spinal deformity surgery who received IM and who did not. Patients 21 years of age or less who had a posterior spinal fusion (PSF) with segmental spinal instrumentation (SSI), and received 9–19 mcg/kg (up to 1 mg) of IM were included. Early onset scoliosis surgical patients were excluded. We assessed demographics, pain scores, time to first dose of opioids, diagnoses, surgical time, paediatric intensive care unit (PICU) admission and IM complications (respiratory depression, pruritus, nausea/ vomiting). There were 986 patients who met inclusion criteria. This included 760 patients who received IM and 226 who did not. IM was not used for short procedures (< 3 hrs), respiratory concerns, unsuccessful access of intrathecal space, paraplegia, and anesthesiologist decision. Both groups followed the same strict perioperative care path. The patients were divided into 5 diagnostic groups (IM / non IM patients): idiopathic (578/28), neuromuscular (100/151), syndromic (36/17), and congenital scoliosis (32/21) and kyphosis (14/9). Females predominated over males (697/289). The first dose of opioids after surgery was delayed for a mean of 10.6 hrs in IM group compared to 2.3 hrs in the non-IM group (p=0.001). The postoperative pain scores were significantly lower in the IM groups in the Post Anesthesia Care Unite (p=0.001). Only 17 IM patients (2%) were admitted to the PICU for observation secondary to respiratory depression, none required re-intubation. None of the IM group were re-intubated. Forty-nine patients (6%) experienced pruritus in the IM group compared to 4 of 226 patients (2%) in the non IM group. There were 169 patients (22%) of the IM patients and 21 patients (9%) of the non IM had nausea and vomiting postoperatively. Three patients (0.39%) had a dural leak from the administration of IM but did not require surgical repair. There were no other perioperative complications related to the use of IM. There were no significant group differences. Pre-incision IM is a safe and effective adjunct for pain management in all diagnostic groups undergoing spinal surgery. The IM patients had lower pain scores and a longer time to first administration of post-operative opioids. Although there is an increased frequency of respiratory depression, pruritus, and nausea/vomiting in the IM group, there were no serious complications

Aim:. Deep infection following paediatric spinal deformity surgery is a serious complication, which can also result in increased length of stay and significant cost implications. Our objective was to reduce deep infection rates following spinal deformity surgery. Method:. All paediatric patients undergoing spinal deformity procedures between 2008 and 2010 (group 1) were prospectively followed up and deep infection rates recorded. In 2010, a review of infection rates necessitated a change in pre-operative, peri-operative, and post-operative practice. A scoliosis wound care pathway was implemented, which involved insertion of drains to protect wounds, strict dressing management performed by a Spinal Nurse Practitioner, and a telephone helpline for concerns about wound care and general peri-operative scoliosis care. The use of betadine wash and local antibiotic application intra-operatively were other measures instigated later in this period. All paediatric patients undergoing surgery between 2011 and 2012 (group 2) were then followed up and differences in infection rates between the two groups were analysed. Results:. 260 patients undergoing 275 procedures were included in this study. Numbers of operations increased from 38 in 2008 to 71 in 2012. There were 19 neuromuscular, 19 congenital, and 42 idiopathic cases in group 1 and 15, 35, and 84 in group 2. Deep infection rates reduced significantly from 15% to 0.75% (p<0.0001). Discussion:. Deep infection rates following paediatric spinal deformity surgery can be significantly reduced by use of a team-based multi-modal approach. A robust scoliosis wound care pathway is essential to maintain high standards post-operatively. Conflict Of Interest Statement: No conflict of interest

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 spinal cord monitoring. Level of evidence: III. Cite this article: Bone Joint J 2021;103-B(3):547–552

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 spinal cord monitoring during adult and paediatric spinal deformity surgery between Jan 2009 and Dec 2012 were prospectively followed. The use of somatosensory-evoked potentials (SSEPs) and motor-evoked potentials (MEPs) was recorded and monitoring outcomes were compared to post-operative clinical neurological outcomes. Compliance with the national ANS/BSCN guidelines was assessed. Results:. 333 patients were included in this study. IOM was successful in 312 patients (94%), with both MEPs and SSEPs obtained in 282 patients (85%). SEPs were achieved in 91% and MEPs in 87%. Aetiology was idiopathic in 199 cases, 53 neuromuscular, 28 degenerative, 16 congenital, 16 other. Nine patients had changes in IOM related to surgical activity; six had MEP changes only, three had MEPs and SSEPs changes. All but one of these changes returned to baseline following surgical action; the one remaining patient had a temporary postoperative neurological deficit. One patient had a post-operative single radiculopathy requiring surgical exploration, without change in initial IOM. Final IOM findings demonstrated a positive predictive value (PPV) of 1 and a negative predictive value (NPV) of 0.996. Discussion:. IOM is essential during spinal deformity surgery and, using MEPs, has a high PPV and NPV. Our unit meets guidelines for MEP use and frequently meets guidelines for SSEP use. Conflict Of Interest Statement: No conflict of interest

Introduction: It is the accepted dogma that should paralysis complicate spinal deformity surgery, then the internal fixation should be removed within three hours. This dogma is based on MacEwen’s paper in 1975 which related to the Harrington system and which did not contain statistical analysis (MacEwen G.D. et al, JBJS 557A, 1975,404-8). Since that time spinal cord monitoring systems have been developed and internal fixation systems have become considerably more complex. Does the accepted dogma need to be reviewed?. Methods and results: The author has reviewed the literature which contains statistical analysis of risk factors and results in relation to major neurological complications of spinal deformity surgery (Dove J. Résonance Européenes du Rachis 1999, 7[23]961–66). The risk factors are adult scoliosis, congenital and neuromuscular curves, kyphosis, combined anterior and posterior surgery, intra-operative hypertension, distraction and certain types of segmental fixation. Furthermore these risks are additive. MacEwen’s 1975 paper did not include statistical analysis and its conclusions are not borne out by the information within the paper. The only statistical analysis of the management of neurological complications has shown that surgical removal of the internal fixation was not related to neurological recovery (Paonessa K.G., Hutching F. Scoliosis Research Society Meeting. New York. Sept 1998). Conclusion: Based on an analysis of the relevant literature and current clinical practice, the author suggests an algorithm to be followed by the surgeon faced with a major neurological complication of spinal deformity surgery. The author also raises the question as to whether the British Scoliosis Society should make a statement regarding “best practice” in such cases

The K2M MESA Rail is a new implant with a unique beam-like design which provides increased rigidity compared with a standard circular rod of equivalent diameter potentially allowing greater control and maintenance of correction. The aim of this study was to review our early experience of this implant. We retrospectively reviewed the case notes and radiographs of all consecutive cases of spinal deformity correction in which at least one rail was used. All radiological measurements were made according to the Scoliosis Research Society definitions. Since June 2012 thirty-three cases of spinal deformity correction were performed using the K2M Rail system. One case was excluded as there were no pre-operative radiographs. Median age was 15 years; there were 23 females. There were 26 scoliosis cases of which two had associated Chiari malformation, three were neuromuscular, and the remainder were adolescent idiopathic cases. Six patients had kyphotic deformity secondary to Scheuermann's disease. Mean length of follow-up was 16 months. In the scoliosis cases the mean pre-operative Cobb angle of the major curve was 58.6° with a mean correction of 35.6°. The mean post-operative thoracic kyphosis was 21.1°. The median number of levels included in the correction was 13. Bilateral rails were used in four cases, the remainder had one rail on the concave side and a contralateral rod. No patients required an anterior release or staged surgery. All kyphosis cases had posterior apical corrective osteotomies. The mean pre-operative thoracic kyphosis was 75.5° with a mean correction of 31°. The median number of levels included in the correction was 11. Four patients had bilateral rails. No patients required anterior release. Complications: two patients had prominent hardware. One patient had a malpositioned screw causing nerve root irritation, which was removed. There were three superficial infections, which settled with antibiotics. There were no cases of implant breakage, screw pull-out, or loss of correction. The K2M MESA Rail is a powerful new implant design which helps to achieve and maintain satisfactory correction of complex spinal deformity, and is particularly strong at correcting kyphotic deformity. It also enables restoration of normal thoracic kyphosis, particularly in idiopathic thoracic curves, which tend to be lordosing. This may prevent thoracic flat back and potential long-term sequelae. Early results show that the system is as safe and effective as other posterior deformity correction implants on the market, however, it requires further prospective follow-up to ascertain its outcomes in the long-term

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 spinal cord monitoring allows this risk to be reduced by providing feedback to the surgeon while the corrective manoeuvres are performed. Although ideally a trained technician with multimodal monitoring is recommended, it is often not an option in a resource limited environment and surgeon operated technology is used. Aim:. to evaluate the use of surgeon operated trans-cranial motor evoked potentials (tcMEP) in spinal deformity surgery. Methods:. A retrospective review was conducted on a single surgeon series of 108 consecutive cases utilising the NIM system (Medtronic). Percutaneous needles were employed in the scalp, both hands and feet to allow the upper limbs to act as controls. Forty-nine patients were 13 years old or less, 47 were 14–18, and 12 adults. The cohort consisted of 54 AIS, 27 neuromuscular scoliosis, 14 congenital, 2 old TB and 11 miscellaneous. The vast majority were posterior based procedures. Results:. In 4 cases initial traces could not be obtained. One was a severe myelopathy and further efforts to monitor were abandoned. In one case the anaesthetist had broken protocol and once converted to TIVA the traces improved. Two others were poor initially but improved as the case progressed. In 8 cases intra-operative traces were lost. One was thought to be due to hypothermia and the patient woke intact. Two were unrelated to surgical intervention and recovered spontaneously with patients waking intact. Four cases deteriorated during the corrective manoeuvre (one delayed) and recovered with reduction of correction. One case required removal of instrumentation after repeated loss each time rods were inserted and awoke with a weak leg but recovered and was re-operated two weeks later. Conclusion:. Surgeon operated tcMEP's allows feedback in terms of safety of deformity correction with a 100% negative predictive value and an 8% incidence of signal loss during correction allowing immediate remedial action

Purpose of Study: To observe the efficiency of the combined motor-somatosensory monitoring and somatosensory-alone monitoring to identify the intra-operative neurologic changes. Methods and Results: We retrospectively assessed 123 cases in our centre, who had complete neurophysiological report while undergoing corrective spinal deformity surgery with spinal monitoring, from 2004 to 2008. Combined motor-somatosensory, somatosensory-alone and motor-alone monitoring were applied in sixty five, fifty and eight operations, respectively. We also looked at the factors that could potentially affect the neuro-physiologic monitoring, such as preoperative neurological status, anaesthetic method, blood loss, competency level of the monitoring team and the reaction of the surgical team to a significant monitoring event. In total, there were only two cases of true positive event, defined as a significant intraoperative event and postoperative neurological deficit. Both of these cases had combined monitoring during their procedures. No case of false negative was observed. There were also five cases with a significant intraoperative event without post operative neurologic sequel (false positive). Four of these had combined monitoring, with complete normal sensory monitoring and abnormal motor monitoring, which prompted the operating team to the appropriate action. Conclusion: Based on this observation, it is felt that the combined monitoring during spinal deformity correction procedures is superior to the sensory-alone monitoring for identifying the impending neurologic deficits. This is in accordance with the previous reports and recommendations

Study Design: A prospective observational study of scoliosis patients who were on non-invasive night ventilation for respiratory failure. Objective: To report the results of spinal deformity correction in a group of patients with progressive scoliosis and rare forms of muscular dystrophy/myopathy with respiratory failure who were on nocturnal ventilatory support at the time of surgery. Subjects: 9 patients (6 males, 3 females) with scoliosis and respiratory failure. The mean age at surgery was 12.4years (range 8–16yrs). There were 4 patients with multicore myopathy, 2 with merocin negative congenital muscular dystrophy, 1 with Ullrichs muscular dystrophy, 1 patient with congenital AcylCOA dehyrogenase deficiency and 1 with congenital scoliosis and dextrocardia. All the patients had overnight pulse oximetry, which showed episodes of desaturation at night. This was reversed with the onset of nocturnal ventilation. All the patients underwent posterior fusion performed by the same surgeon. Mean follow-up was 40 months (range 10 to 75). Outcome Measures: Lung function, Cobb angle, Length of ICU stay, complications. Results: Mean vital capacity at time of surgery was 20% (range 13–28%). All patients recovered well following surgery with no cardiac or pulmonary complications. The mean stay in the ICU was 2.7 days (range 2–5). The mean hospital stay was 14.2 days (range 10–21). The mean preoperative Cobb angle was 70.2 degrees (range 55–85). The average change in the Cobb angle post-operatively was 32 degrees (range 16–65 degrees). The mean vital capacity of patients at latest follow up was 18% (range 10–32%). There was no loss of correction at latest follow-up. None of these patients lost their ambulatory capacity following surgery. Conclusion: This is the first study reporting results of deformity correction in patients on ventilatory support. Spinal deformity correction in patients on non-invasive nocturnal ventilation presented no increased risk of complications

Introduction Transcranial motor evoked potentials are routinely used at The Children’s Hospital at Westmead to monitor the spinal cord in spinal surgery. This study is a prospective review of all spinal cord monitoring procedures from 1999 to 2004 in patients undergoing elective spinal deformity correction surgery at The Children’s Hospital at Westmead and Westmead Hospital. Spinal cord monitoring with Somatosensory Evoked Potentials (SSEP) and MEP has been widely used in combination during spinal surgery with good sensitivity and specificity. The use of CMAP as the only modality has not been widely used and its efficacy has not been fully elucidated. Using MEP and CMAP only may increase the sensitivity of spinal cord monitoring compared with combined SSEP and MEP monitoring. Methods The intra-operative monitoring outcomes were compared with patient’s post-operative clinical outcomes. The sensitivity and specificity were calculated and determined for our monitoring protocol. Results Transcranial MEPs were measured in 146 patients in 175 procedures. In 2 patients (2 procedures) we were unable to record any CMAPS. There were 15 intra-operative monitoring changes (8.7%). There were no new post-operative neurological deficits. Our results compare favourably to the literature with respect to the false-negative rate or new neurological events. Discussion Using our anaesthetic protocol and spinal monitoring criteria, we were able to successfully monitor patients undergoing elective spinal deformity correction surgery for a variety of diagnoses. The monitoring criteria are sufficiently strict to achieve a sensitivity of 1.0 (95%CI = 0.66–1.00) and a specificity of 0.97 (95%CI = 0.83–0.99). Monitoring of CMAPs alone has been adequate to avoid clinical neurological deficits

Introduction: Complications of homologous blood transfusion include transmission of infection and development of antibodies. Autologous pre-donation, acute normo-volaemic haemodilution and cell salvage have been used to reduce the use of homologous transfusions. Surgery for spinal deformities often requires blood transfusion. In February 1999, we started an autologous pre-donation programme for children undergoing spinal deformity surgery. Methods and results: The case records of the first 15 patients who took part in the programme have been scrutinised and data about pre-donation, haemoglobin, pre- and post-operative hameoglobin, blood loss, blood transfusions, use of blood products, and complications related to pre-donation of blood were obtained and analysed. Similar data from case records of 15 patients, who had surgery for spinal deformities before start of the programme, were used as control. In the autologous pre-donation group, four received homologous transfusion and 11 escaped exposure to homologous blood or blood products. In comparison in control group 14 out of 15 received homologous transfusion. There was no significant difference between the two groups in terms of diagnosis, operating time, postoperative haemoglobin, body weight and age. Mean operative blood loss in autologous group was less (1190 mls) than in that of the control group (1529 mls). Of the four patients who received homologous transfusion, two were transfused outside the hospital protocol. Complications from pre-donation of blood occurred in three patients and were minor. They included minor bruising in two and difficult and painful venous cannulation in one. Conclusion: In our practice autologous pre-donation resulted in avoidance of homologous blood transfusion in three quarters of patients undergoing spinal deformity surgery. By adopting strategies such as acute normo-volaemic haemodilution, cell salvage and strictly adhering to protocols for prescribing transfusion, we believe that the need for homologous transfusion could be obviated except in extreme cases

The February 2023 Spine Roundup. 360. looks at: S2AI screws: At what cost?; Just how good is spinal deformity surgery?; Is 80 years of age too late in the day for spine surgery?; Factors affecting the accuracy of pedicle screw placement in robot-assisted surgery; Factors causing delay in discharge in patients eligible for ambulatory lumbar fusion surgery; Anterior cervical discectomy or fusion and selective laminoplasty for cervical spondylotic myelopathy; Surgery for cervical radiculopathy: what is the complication burden?; Hypercholesterolemia and neck pain; Return to work after surgery for cervical radiculopathy: a nationwide registry-based observational study

Aims

Postoperative complication rates remain relatively high after adult spinal deformity (ASD) surgery. The extent to which modifiable patient-related factors influence complication rates in patients with ASD has not been effectively evaluated. The aim of this retrospective cohort study was to evaluate the association between modifiable patient-related factors and complications after corrective surgery for ASD.

Purpose: Despite advances in surgical technique, neurological injury remains a potentially devastating complication of spinal deformity correction surgery. The purpose of the study is to describe surgical and patient factors associated with “electrophysiologic (EP) events” and neurogenic deficits. Method: A retrospective chart review, looking at “EP events” during surgery, was conducted on 162 patients who received surgical treatment of their pediatric spine deformity from 1999 to 2004. Results: Ninety three percent of cases (n=151) were successfully monitored by either somatosensory evoked potential (SEP) or motor evoked potential (MEP) monitoring. All three neurologic deficits that occurred in this study cases were successfully detected by EP monitoring (0.02%, p=.002). In those 151 cases that were successfully monitored, “EP events” were occured in twenty (13.2%) cases. The most common cause was systemic change (45%) and curve correction (40%). In those 20 cases, when corrective actions were made (n=15) “EP events” reversed to baseline values in all cases. When no corrective actions were taken (N=5) there was no reversals of “EP events” to baseline. Patients with kyphosis had a trend toward significantly higher rates of “EP events” (p=.174) and patients who had cardiopulmonary comorbidities had significantly higher rates of “EP events” (p=.007). Conclusion: Consistent with existing literature, the EP monitoring was successful in the vast majority of deformity surgeries. “EP events” were able to be reversed with corrective action and to predict neurologic deficits. Our study found that patients with kyphosis and/or cardiopulmonary comorbidities have higher risk of significant “EP events” during the surgeries

Aim:. An analysis of significant neuromonitoring changes (NMCs) and evaluation of the efficacy of multimodality neuromonitoring in spinal deformity surgery. Method:. A retrospective review of prospectively collected data in 320 consecutive paediatric and adult spinal deformity operations. Patients were sub-grouped according to demographics (age, gender), diagnosis, radiographic findings (Cobb angles, MR abnormalities) and operative features (surgical approach, duration, levels of fixation). Post-operative neurological deficit was documented and defined as either spinal cord or nerve root deficit. Results:. 296 paediatric and adult patients were monitored in 320 consecutive spinal deformity operations between 2003 and 2013. Combined monitoring with SSEPs and MEPs was considered successful (296 of 320 operations), when it was able to produce reproducible signals with regards to SEP and / or MEP. SEP was attempted but unrecordable in 1 case, while MEPs were contraindicated in 23 cases due to epilepsy and/or medications. The overall incidence of significant NMC was 7.5% (24 NMCs out of 320 operating episodes) and overall neurological deficit was 1.6%. There were 19 true positives, 5 false positives and zero false negative results. When results were collated, the overall combined sensitivity of multimodal monitoring was 100%, specificity 98.3%, PPV 79.2% and NPV 98.3%. Discussion:. Multimodal monitoring allows accurate assessment and prevention of permanent neurological deficit that is superior to any single monitoring modality. Conflict Of Interest Statement: No conflict of interest

Introduction. Somatosensory evoked potential (SSEP) monitoring allows for assessment of the spinal cord and susceptible structures during complex spinal surgery. It is well validated for the detection of potential neurological injury but little is known of surgeon's responses to an abnormal trace and its effect on neurological outcome. We aimed to investigate this in spinal deformity patients who are particularly vulnerable during their corrective surgery. Methods. Our institutional neurophysiology database was analysed between 1. st. October 2005 and 31. st. March 2010. Monitoring was performed by a team of trained neurophysiology technicians who were separate from the surgical team. A significant trace was defined as a 50% reduction in trace amplitude or a 10% increase in signal latency. Patients suffering a significant trace event were examined post-operatively by a Consultant Neurologist who was separate from the surgical team. Results. 2386 consecutive operations (F:1719, M:667 median age 16 yrs) were performed in the time period and 72 operations reported a significant trace event (‘red alert’). From these cases 47 (65%) had a clearly documented intervention by the surgeon and 7 patients overall suffered a lasting neurological deficit (0.3%). The most common timing events were during instrumentation (50%) and during correction/distraction (16%). Most common responses were optimisation of patient/monitoring set-up (23%) and adjustment of metalwork (22%). There were 18 wake-up tests performed. We found SSEP monitoring to have a sensitivity of 100%, specificity 97.4%, positive predictive value 14% and negative predictive value 100%. A Chi-square test (p=0.016) was significant suggesting intervention had a beneficial effect on neurological outcome. Conclusion. We would advocate the use of SSEP monitoring in all patients undergoing spinal deformity surgery. These patients tend to be young, neurologically intact pre-operatively and are particularly vulnerable to the large corrective forces their surgery requires

There is a wide range of reports on the prevalence of neurological injuries during scoliosis surgery, however this should depend on the subtypes and severity of the deformity. Furthermore, anterior versus posterior corrections pose different stresses to the spine, further quantifications of neurological risks are presented.

Neuromonitoring data was prospectively entered, and the database between 2006 and 2012 was interrogated. All deformity cases under the age of 21 were included. Tumour, fracture, infection and revision cases were excluded.

All “red alerts” were identified and detailed examinations of the neuromonitoring records, clinical notes and radiographs were made. Diagnosis, deformity severity and operative details were recorded.

2290 deformity operations were performed: 2068 scoliosis (1636 idiopathic, 204 neuromuscular, 216 syndromic, and 12 others), 89 kyphosis, 54 growing rod procedures, and 80 operations for hemivertebra. 696 anterior and 1363 posterior operations were performed for scoliosis (8 not recorded), and 38 anterior and 51 posterior kyphosis correction.

67 “red alerts” were identified, there were 14 transient and 6 permanent neurological injuries. 62 were during posterior stage (24 idiopathic, 21 neuromuscular, 15 syndromic (2 kyphosis), 1 growing rod procedure, 1 haemivertebra), and 5 were during anterior stage (4 idiopathic scoliosis and 1 syndromic kyphosis). Average Cobb angle was 88°. 1 permanent injuries were during correction for kyphosis, and 5 were for scoliosis (4 syndromic, 1 neuromuscular, and 1 anterior idiopathic).

Common reactions after “red alerts” were surgical pause with anaesthetic interventions (n=39) and the Stagnara wake-up test (n=22). Metalwork was partially removed in 20, revised in 12 and completely removed in 9. 13 procedures were abandoned.

The overall risk of permanent neurological injuries was 0.2%, the highest risk groups were posterior corrections for kyphosis and scoliosis associated with a syndrome. 4% of all posterior deformity corrections had “red alerts”, and 0.3% resulted in permanent injuries; compared to 0.6% “red alerts” and 0.3% permanent injuries for anterior surgery. The overall risk for idiopathic scoliosis was 0.06%.