Feasibility, Safety and Reliability of Surgeon-Directed Transcranial Motor Evoked Potentials Monitoring in Scoliosis Surgery.

(1) Background: Neuromonitoring is essential in corrective surgery for scoliosis. Our aim was to assess the feasibility, safety and reliability of "surgeon-directed" intraoperative monitoring transcranial motor evoked potentials (MEP) of patients. (2) Methods: A retrospective single-center study of a cohort of 190 scoliosis surgeries, monitored by NIM ECLIPSE (Medtronic), between 2017 and 2021. Girls (144) and boys (46) (mean age of 15 years) were included. There were 149 idiopathic and 41 secondary scoliosis. The monitoring consisted of stimulating the primary motor cortex to record the MEP with muscular recording on the thenar, vastus lateralis, tibialis anterior and adductor hallucis muscles. (3) Results: The monitoring data was usable in 180 cases (94.7%), with 178 true negatives, no false negatives and one false positive. There was one true positive case. The predictive negative value was 100%. The monitoring data was unusable in 10 cases (i.e., three idiopathic and seven secondary scoliosis). (4) Conclusions: Simplified transcranial MEP monitoring known as "surgeon-directed module" is usable, safety and reliable in surgery for moderate scoliosis. It is feasible in 95% of cases with a negative predictive value of 100%.

Evaluation of surgical outcomes of calcaneonavicular coalition and too-long anterior process in children: A prospective study.

INTRODUCTION: Calcaneonavicular coalitions (CC) affect approximately 1% of the general population. CC or Too-long anterior process (TLAP) result in "repeated sprains" that can be associated with foot and/or ankle chronic pain. The main objective of this study was to analyze the effectiveness of surgery using the AOFAS score. HYPOTHESIS: Functional results after surgical treatment of CC or TLAP are not as good as expected. MATERIALS AND METHODS: A single-center prospective study was carried out at our University Hospital from 01/01/2019 to 06/01/2021. The patients included were operated on in the pediatric surgery department for CC or TLAP resection by direct approach after MRI confirmation and failure of non-operative treatment. A survey evaluating the AOFAS score as well as the number of ankle sprains and the intensity of pain was undertaken at the preoperative consultation and then at three and twelve months postoperatively. RESULTS: A total of 17 feet in 16 patients (14 girls and 2 boys) comprising 12 TLAP and 5 CC were included. The AOFAS score was statistically significantly increased (58.6 vs. 82.9; p<0.001) postoperatively. No statistical difference was noted between the follow-up visits at three and twelve months. At the twelve-month follow-up, 9 out of 16 patients (56.2%) still reported activity restrictions; mainly linked to the persistence of chronic pain, and 10 out of 16 patients (62.5%) reported a feeling of instability. DISCUSSION: CC and TLAP surgery rapidly improves function but it does not dramatically reduce foot pain and activity restrictions. A dedicated score would be useful to identify patients who will benefit the most from surgery. LEVEL OF EVIDENCE: IV; prospective study.

Pediatric traumatology in "green zone" during Covid-19 lockdown: A single-center study.

INTRODUCTION: The 8-week lockdown for the Covid-19 epidemic in France restricted travel, and interrupted schooling and sports. The study hypothesis was that this exceptional situation temporarily altered childhood trauma epidemiology. MATERIAL AND METHOD: A prospective study was performed during the 8 weeks of lockdown. Pediatric traumatology emergency activity was compared to that during the same period in the previous 3 years. RESULTS: During lockdown, emergency consultations decreased by 50%. The number of patients operated on was 86% of that in the previous 3 years. Patients operated on during lockdown had a mean age of 7.6 years (median, 7.5 years) compared to 9.3 years (9.4 years). The rate of domestic accidents (59% versus 23%) and trampoline accidents (16% versus 5%) increased, while those of sport and locomotion-related accidents decreased. Wounds were more frequent, at 35% of procedures, versus 13% previously. The rate of surgery for upper-limb fracture deceased, while that of lower-limb fracture was unchanged. Distal forearm fracture was less frequent, as was distal tibial fracture. DISCUSSION: The present study found a 50% decrease in pediatric traumatology emergency activity during lockdown, without decrease in surgery. In case of renewed lockdown, we recommend reorganizing emergency admission to free teams for management of Covid-19 patients, while maintaining operative rooms for emergency surgery. A general public information campaign could help prevent domestic accidents and risk related to use of trampolines. LEVEL OF EVIDENCE: III.

Diffusion properties of asymptomatic lumbar intervertebral discs in a pediatric cohort: a preliminary study of apparent diffusion coefficient.

PURPOSE: To explore the apparent diffusion coefficients of intervertebral discs in an asymptomatic pediatric cohort. METHODS: We conducted a prospective MRI study of the lumbar spine from below the thoracolumbar junction to the lumbosacral junction on 12 subjects (mean age 13 y.o.) with no spinal pathology or spinal posture disorder. MRI was carried out using a 1.5 T machine with acquisitions realized both in sagittal and coronal planes. First, disc hydration was determined, and then, diffusion-weighted images were obtained using an SE single-shot echo-planar sequence. Apparent diffusion coefficients (ADC) of anterior annulus fibrosus (AAF), nucleus pulposus (NP) and posterior annulus fibrosus (PAF) were measured in the sagittal plane. RESULTS: Averaged hydration of 0.27 SD 0.03 confirmed the asymptomatic nature of discs. Average scaled values of ADC were 0.46 SD 0.01, 0.22 SD 0.09 and 0.18 SD 0.03 for NP, AAF and PAF, respectively. ADC of NP were almost constant along the spine; PAF values show a slight increase in the thorax-sacrum direction, while AAF values showed a pronounced decrease. Locally, ADC of AAF was higher compared to ADC PAF values below the thoracolumbar junction and it reversed for subjacent discs. CONCLUSIONS: In our knowledge, our study provided the first diffusive properties of asymptomatic intervertebral discs in an adolescent cohort. ADC of NP was slightly higher than adults'. ADC evolutions of AAF were correlated with lordosis concavity which pointed out the role of compressive strain on fluid transport properties. This study could furnish information about segment homeostasis for exploration of pediatric spinal pathologies.

Side bending radiographs and lowest instrumented vertebra in adolescent idiopathic scoliosis: A French quality-of-care study.

BACKGROUND: Determining which spinal levels to instrument during surgical treatment of Lenke Type 1 adolescent idiopathic scoliosis (AIS) depends on the reducibility of the primary and secondary curve patterns. This reducibility can be evaluated in several ways, with the most popular being radiographs in bending for moderate thoracic and lumbar curvatures. Hypothesis Side-bending radiographs will alter the choice of the lowest instrumented vertebra (LIV) for the surgical treatment of AIS. METHODS: Thirteen experienced French spine surgeons were invited to perform surgical planning on 23 patients based on stereoradiographs with and without (standing) side-bending views. The surgical planning was repeated a second time to assess the intra- and inter-rater reliability. Variations in the choice of LIV were analyzed for each evaluation. RESULTS: The intra-rater reliability was moderate to substantial. The inter-rater reliability was low to moderate. The study compared 879 surgical plans. Selective fusion was chosen in 0.3% of the plans. The median LIV was L2. The availability of side bending views changed the plan in 39% of cases. However, 36% of the plans were changed in the control (test-retest) condition. No significant difference was found between the variations with side-bending radiographs and "control" variations (p>0.05). CONCLUSION: The use of radiographs in bending has no significant effect on the LIV choice in this study. This result is derived from statistically robust analysis made possible by one of the largest datasets available on this topic. Large inter-rater variability was observed and will be explored further in a future study. LEVEL OF EVIDENCE: II; non-randomized controlled comparative study.

Proximal Fixation in Adolescent Scoliosis Lenke 1 and 3 Treated by Posteromedial Translation Using Sublaminar Bands: Transverse-pedicular Hook Claw Versus Transverse Hook-pedicular Screw Claw.

STUDY DESIGN: This is retrospective comparative study. SUMMARY OR BACKGROUND DATA: Numerous studies have focused on the efficacy, safety, and restoration of thoracic kyphosis in adolescent idiopathic scoliosis surgery using posteromedial translation method with sublaminar bands and hook claws at the top. The relevance of exchanging the penultimate anchor, that is, the pedicle hook with a pedicle screw in a hybrid construction has not yet been assessed. OBJECTIVE: Our objective was to assess, in adolescent scoliosis Lenke 1 and 3 operated by posteromedial translation using sublaminar bands, the proximal fixation claw influence (transverse-pedicular hook vs. transverse hook-pedicular screw) for postoperative correction and the proximal junctional kyphosis (PJK) at 2 years follow-up. MATERIALS AND METHODS: A comparative monocentric retrospective study included adolescent idiopathic scoliosis thoracic requiring surgery, between 2015 and 2017, with 2 years follow-up. Clinical (complications, revision surgery, and scoliosis research society-30) and radiographic (coronal and sagittal parameters) assessment were reported. Radiologic PJK was defined by a proximal junctional angle increase of 10 degrees or more between postoperative period and the last follow-up. RESULTS: Sixty patients (age at surgery=16±2 y; mean Cobb angle=58.2±12 degrees) were divided into 2 similar groups according to upper fixation: transverse-pedicular hook (H-H) and transverse hook-pedicle screw (S-H). No statistical differences were found for correction parameters (P>0.05). We reported 2 cases of PJK in H-H group (N=2/30=6.6%) and none in S-H group (N=0/30) (P=0.1) none requiring revision. No infectious or neurological events were reported. Mean scoliosis research society-30 was 126±12.7 in H-H group whereas 129.3±10 in S-H group (P=0.4). CONCLUSIONS: No differences in postoperative correction and clinical results at 2 years follow-up were found. A claw with transverse-pedicular hook increase proximal junctional angle without significant increase on radiographic PJK incidence compared with a claw with transverse hook and pedicle screws.

An energy approach describes spine equilibrium in adolescent idiopathic scoliosis.

The adolescent idiopathic scoliosis (AIS) is a 3D deformity of the spine whose origin is unknown and clinical evolution unpredictable. In this work, a mixed theoretical and numerical approach based on energetic considerations is proposed to study the global spine deformations. The introduced mechanical model aims at overcoming the limitations of computational cost and high variability in physical parameters. The model is constituted of rigid vertebral bodies associated with 3D effective stiffness tensors. The spine equilibrium is found using minimization methods of the mechanical total energy which circumvents forces and loading calculation. The values of the model parameters exhibited in the stiffness tensor are retrieved using a combination of clinical images post-processing and inverse algorithms implementation. Energy distribution patterns can then be evaluated at the global spine scale to investigate given time patient-specific features. To verify the reliability of the numerical methods, a simplified model of spine was implemented. The methodology was then applied to a clinical case of AIS (13-year-old girl, Lenke 1A). Comparisons of the numerical spine geometry with clinical data equilibria showed numerical calculations were performed with great accuracy. The patient follow-up allowed us to highlight the energetic role of the apical and junctional zones of the deformed spine, the repercussion of sagittal bending in sacro-illiac junctions and the significant role of torsion with scoliosis aggravation. Tangible comparisons of output measures with clinical pathology knowledge provided a reliable basis for further use of those numerical developments in AIS classification, scoliosis evolution prediction and potentially surgical planning.

Epidemiology of spinal fractures in children: Cross-sectional study.

INTRODUCTION: Epidemiological studies of fractures of the spine in children are all old, mostly single-centre, with series spanning periods of 5 to 20 years. HYPOTHESIS: As lifestyle is constantly changing, notably with an increase in sports activities and improvements in the prevention of road and household accidents, epidemiology has likely changed. OBJECTIVE: To update the description of spinal trauma in children and adolescents compared to the existing literature. MATERIAL AND METHOD: A multicentre cross-sectional study of spinal fracture, dislocation and spinal cord injury without radiological abnormality (SCIWORA) in children was carried out in 15 French university hospital centres, for a period of one year (2016). RESULTS: One hundred and sixty-five children were identified: 85 girls, 80 boys; mean age 11 years (range, 10 months-17 years); median, 12 years 6 months. One hundred and fifty-two children (92%) had fracture, 8 (5%) dislocation (including 7 C1-C2 rotary dislocations), and 5 (3%) SCIWORA. Fractures were multiple in 80 cases (49%), contiguous in 73 cases (91%) and non-contiguous in 7 (9%). Locations were cervical in 25 cases (15%), thoracic in 85 (52%), lumbar in 75 and sacral in 4 (2%). Fracture types comprised 234 vertebral compactions (78%), 25 burst fractures (8%), 5 chance fractures (2%), 2 odontoid fractures, and 33 other lesions. Causes comprised fall in 77 cases (47%), sports accidents in 56 (34%), road accidents in 29 (18%), and others in 3. In 52 cases (32%), there was ≥1 associated lesion: appendicular in 35 cases (67%), thoracic or abdominal in 31 (60%), and head in 16 (31%). Twenty-one cases had multiple lesions (40%). Eighteen cases showed neurological involvement (11%) including 5 SCIWORAs. Neurological complications were more frequent before 9 years of age. CONCLUSION: The epidemiology of spine fractures in children has slightly changed. There are now fewer cervical lesions. Causes are less often road accidents and more often sports accidents. Multi-level lesions remain frequent and the rate of neurological complications is around 10%. Compaction fracture is the most common type.

Prediction of clinical height gain from surgical posterior correction of idiopathic scoliosis.

OBJECTIVE: The best predictors of height gain due to surgical correction are the number of fused vertebrae and the degrees of the corrected Cobb angle. Existing studies of predictive models measured the radiographic spinal height and did not report the clinical height gain. The aims of this study were to determine the best predictive factors of clinical height gain before surgical correction, construct a predictive model using patient population data for machine learning, and test the performance of this model on a validation population. METHODS: The authors reviewed 145 medical records of consecutive patients who underwent surgery that included placement of posterior spinal instrumentation and fusion for idiopathic scoliosis between 2012 and 2016. Standing and sitting clinical heights were measured before and after surgery in patients who had been surgically treated under similar conditions. Multivariate analysis was then performed and the results were used to develop a predictive model for height gain after surgery. The data from the included patients were randomly assigned to a learning set or a test set. RESULTS: In total, 116 patients were included in the analysis, for whom the average postoperative clinical height gain in a standing position was 4.2 ± 1.8 cm (range 0-11 cm). The best prediction model was calculated as follows: standing clinical height gain (cm) = 1 - 0.023 × sitting clinical height (cm) - 0.19 × Risser stage + 0.058 × Cobb preoperative angle (°) + 0.021 × T5-12 kyphosis (°) + 0.14 × number of levels fused. In the validation cohort, 91% of the predicted values had an error of less than one-half of the actual height gain. CONCLUSIONS: This predictive model formula for calculating the potential postoperative height gain after surgical treatment can be used preoperatively to inform idiopathic scoliosis patients of what outcomes they may expect from posterior spinal instrumentation and fusion (taking into account the model's uncertainty).

Surgical management of burst fractures in children and adolescents: A Multicentre Retrospective Study.

BACKGROUND: Spinal fractures are rare in children, in whom they contribute only 2% to 5% of all traumatic spinal injuries. The management of burst fractures is well standardised in adults but remains controversial in paediatric patients, due to specific growth-related considerations. The objective of this study was to assess the clinical and radiographic outcomes of surgical management in a multicentre cohort of paediatric patients with burst fractures, in order to devise an optimal therapeutic strategy. HYPOTHESIS: A therapeutic strategy for burst fractures in children and adolescents can be devised based on data from a patient cohort and on previously published information. MATERIAL AND METHODS: Patients younger than 18 years who were managed surgically for one or more burst fractures (Magerl A3) were included in this retrospective multicentre study. Clinical, radiographic, and surgical data were collected before surgery, within 3 months after surgery, and 2 years after surgery. The primary surgical approach was posterior in all patients. Computed tomography (CT) was performed post-operatively to assess the extent of anterior bone loss in order to determine whether anterior fusion was required. The 26 included patients had a mean age of 15±1 years. The thoraco-lumbar spine was involved in 15 (57%) patients. Surgery consisted in correction by instrumentation and posterior fusion only in 14 patients and in posterior correction with anterior fusion in 12 patients. In 10 (38%) patients, the instrumentation extended one vertebra above and one vertebra below the fractured vertebra. RESULTS: Significant correction of the vertebral kyphosis was achieved (17°±11° before vs. 4°±2° after surgery, p=0.001). Anterior and posterior vertebral heights were significantly increased (15±3mm vs. 20±3mm, p=0.01 and 23±4mm vs. 26±4mm, p=0.04, respectively). DISCUSSION: The decision to perform surgery rests on the degree of kyphosis and presence of instability. Anterior bone grafting can be added if the instrumentation is short or a bone defect persists after posterior correction. Correction of the local kyphosis is important to prevent sagittal malalignment with its adverse functional consequences in adulthood. Neural decompression must be performed in patients with neurological deficits. LEVEL OF EVIDENCE: IV.

Proximal junctional kyphosis in thoracic adolescent idiopathic scoliosis: risk factors and compensatory mechanisms in a multicenter national cohort.

INTRODUCTION: Proximal junctional kyphosis (PJK) is a frequent complication, up to 46%, in adolescent idiopathic scoliosis surgical treatment (AIS). Several risk factors have been evoked but remain controversial. The purpose of this study was to analyze the incidence of PJK in a multicenter cohort of AIS patient and to determine risk factor for PJK. MATERIALS AND METHODS: Lenke I and II AIS patients operated between 2011 and 2015 (minimum of 2-years follow-up) were included. On fullspine X-rays, coronal and sagittal radiographic parameters were measured preoperatively, postoperatively and at final follow-up. Occurrence of radiological PJK corresponding to a 10° increase in the sagittal Cobb angle, measured between the upper instrumented vertebra (UIV) and UIV + 2, between postoperative and 2-years follow-up X-rays, was reported. RESULTS: Among the 365 patients included, 15.6% (n = 57) developed a PJK and only 10 patients required a revision surgery. Preoperatively, PJK patients had significantly larger pelvic incidence (57° ± 13° vs. 51° ± 12°), larger lumbar lordosis (LL) (63° ± 12° vs. 57° ± 11°) and bigger C7 slope. Postoperatively (3 months), in the non-PJK group, thoracic kyphosis (TK) was increased and LL was not significantly different. However, postoperatively, in the PJK group, no significant change was observed in TK, whereas C7 slope decreased and LL significantly increased. There was also a postoperative change in inflection point which was located at a more proximal level in the PJK group. Between postoperative time and final follow-up, TK and LL significantly increased in the PJK group. CONCLUSION: PJK is a frequent complication in thoracic AIS, occurring 16%, but remains often asymptomatic (less than 3% of revisions in the entire cohort). An interesting finding is that patients with high pelvic incidence and consequently large LL and TK were more at risk of PJK. As demonstrated in ASD, one of the causes of PJK might be postoperative posterior imbalance that can be due to increased LL, insufficient TK or inflection point shift during surgery. These slides can be retrieved under Electronic Supplementary Material.

Comparison of 8 and 5 mm robotic instruments in small cavities : 5 or 8 mm robotic instruments for small cavities?

INTRODUCTION: Robotic surgery has seen increasing use in the field of pediatric surgery. Our clinical experience suggested instrument size can impact on the surgical ability. This study aimed to compare the performance of robot-assisted laparoscopic skills in confined spaces using either 5 or 8 mm instruments. METHODS: A preclinical randomized crossover study design was implemented. 24 assessors performed three different reproducible drill procedures (M1: peg transfer, M2: circle cutting, M3: intracorporeal suturing). To assess surgical proficiency in confined working spaces, these exercises were performed with 5 and 8 mm instruments of the da Vinci® Surgical Systems Si in a cubic box with 60 mm-sized edges. Each performance was recorded and evaluated by two reviewers using both objective structured assessment of technical skills (OSATS) and global evaluative assessment of robotic skills (GEARS) scores. Parietal iatrogenic impacts and instrument collisions were specifically analyzed using a dedicated scoring system. RESULTS: Regardless of their experience, trainees performed significantly better when using 8 mm instruments in terms of OSATS scores (20.5 vs. 18.4; p < 0.01) and GEARS scores (23.4 vs. 21.9; p < 0.01) for most items, except for "depth perception" and "autonomy." The 8 mm performances involved significantly less parietal box damage (4.1 vs. 3.4; p < 0.01), and tool collisions (4.1 vs. 3.2; p < 0.01). CONCLUSIONS: In light of the better performances with 8 mm tools for specific tasks and parietal sparing constraints in restricted spaces, this study indicates that 5 mm instruments can be deemed to be less effective for reconstructive procedures in small children.

Differential learning processes for laparoscopic and open supraumbilical pyloromyotomy.

PURPOSE: To compare the learning curves for mastering OP and LP surgical techniques, in terms of effects on completion times and postoperative outcomes/complications. METHODS: A retrospective analysis was performed for 198 patients with hypertrophic pyloric stenosis. The learning curves were in regard to two groups of surgeons: three of whom performed 106 OPs while three others performed 92 LPs. Treatment-related complications were divided into two categories: specific complications relating to the pyloromyotomy and non-specific complications. A logistic regression model with repeated data was used to explore the occurrence of complications. RESULTS: The overall postoperative complication rates were not significantly different between the OP (15.1 %) and the LP (11.8 %) groups. Specific complications were more frequent in the LP group (6.4 versus 2.8 %), while non-specific complications were more frequent in the OP group (12.1 versus 5.3 %). The occurrence of complications exhibited a statistically decreasing risk with each supplementary procedure that was performed (p = 0.0067) in the LP group, but not in the OP group (p = 0.9665). CONCLUSION: From a learning process perspective, laparoscopy is mainly associated with a significantly higher risk of specific complications. This risk decreases in line with the surgeon's level of experience, whereas non-specific complications remain stable in open procedures.