Intratumoral Heterogeneity Assessment of the Extracellular Bone Matrix and Immune Microenvironment in Osteosarcoma Using Digital Imaging to Predict Therapeutic Response.

The assessment of chemotherapy response in osteosarcoma (OS) based on the average percentage of viable cells is limited, as it overlooks the spatial heterogeneity of tumor cell response (foci of resistant cells), immune microenvironment, and bone microarchitecture. Despite the resulting positive classification for response to chemotherapy, some patients experience early metastatic recurrence, demonstrating that our conventional tools for evaluating treatment response are insufficient. We studied the interactions between tumor cells, immune cells (lymphocytes, histiocytes, and osteoclasts), and bone extracellular matrix (ECM) in 18 surgical resection samples of OS using multiplex and conventional immunohistochemistry (IHC: CD8, CD163, CD68, and SATB2), combined with multiscale characterization approaches in territories of good and poor response (GRT/PRT) to treatment. GRT and PRT were defined as subregions with <10% and ≥10% of viable tumor cells, respectively. Local correlations between bone ECM porosity and density of immune cells were assessed in these territories. Immune cell density was then correlated to overall patient survival. Two patterns were identified for histiocytes and osteoclasts. In poor responder patients, CD68 osteoclast density exceeded that of CD163 histiocytes but was not related to bone ECM load. Conversely, in good responder patients, CD163 histiocytes were more numerous than CD68 osteoclasts. For both of them, a significant negative local correlation with bone ECM porosity was found (P < .01). Moreover, in PRT, multinucleated osteoclasts were rounded and intermingled with tumor cells, whereas in GRT, they were elongated and found in close contact with bone trabeculae. CD8 levels were always low in metastatic patients, and those initially considered good responders rapidly died from their disease. The specific recruitment of histiocytes and osteoclasts within the bone ECM, and the level of CD8 represent new features of OS response to treatment. The associated prognostic signatures should be integrated into the therapeutic stratification algorithm of patients after surgery.

Is posterior vertebral arthrodesis at the end of the electromagnetic rod lengthening program necessary for all patients? Comparative analysis of sixty six patients who underwent definitive spinal arthrodesis and twenty four patients with in situ lengthening rods.

PURPOSE: Magnetically controlled growing rods (MCGR) should be removed or changed at most two years after their implantation in the treatment of patients with early-onset scoliosis (EOS) (Safety notice July 2021). However, in the face of patients at high risk of intraoperative complications and relying on the principle of auto-fusion of the spine, some surgeons would prefer a more wait-and-see attitude. The aim of this study was to report on patients who did not undergo final fusion at the end of the lengthening program with MCGR and to compare them with those who did. METHODS: This was a multicenter study with ten centres. We collected all graduate patients with EOS who had received MCGR between 2011 and 2022. RESULTS: A total of 66 patients had final fusion at the end of the lengthening program and 24 patients kept MCGRs in situ. The mean total follow-up time was 66 months (range, 25.3-109), and the mean follow-up time after final lengthening was 24.9 months (range, 3-67.7). Regarding the main curve and thoracic height, there was no significant difference in the percentage of correction over the whole follow-up between the two groups (p = 0.099, p = 0.176) although there was a significant difference between the end of lengthening and the last follow-up (p < 0.001). After completion of the lengthening program, 18 patients who had final fusion developed 24 of the 26 recorded complications (92.3%). CONCLUSION: Contrary to the manufacturer's published safety notice, not all patients systematically benefited from the removal of the MCGRs. Although arthrodesis significantly improved the scoliotic deformity, no significant difference was found in terms of radiographic outcome between patients who underwent spinal fusion and those who kept the MCGRs in situ.

Clinical and radiological results of final fusion in patients who underwent lengthening with magnetically controlled growing rods. About 66 patients with a mean follow-up of 5 years.

PURPOSE: The aim of this study was to evaluate the effects of definitive arthrodesis on frontal and sagittal spine balance in EOS patients treated with MCGR, as well as the complications associated with this procedure and the outcome at last follow-up. METHODS: This was a multicentre study in 10 French centres. All patients who underwent posterior spinal arthrodesis after completion of MCGR treatment, regardless of age, etiology of scoliosis between 2011 and 2022, were included. RESULTS: A total of 66 patients who had a final fusion after the lengthening programme were included in the study. The mean follow-up time was 5.5 ± 1.7 years (range: 2.1-9). The mean follow-up time after arthrodesis was 24 ± 18 months (range: 3-68) and the mean age at arthrodesis was 13.5 ± 1.5 years (range: 9.5-17). The main and secondary curves were significantly (p < 0.005 and p = 0.03) improved by arthrodesis (16.4° and 9° respectively) and stabilised at the last follow-up. The T1-T12 and T1-S1 distances increased by 8.4 mm and 14 mm with spinal fusion, with no significant difference (p = 0.096 and p = 0.068). There was no significant improvement in the rest of the parameters with arthrodesis, nor was there any significant deterioration at last follow-up. After final fusion, there were a total of 24 complications in 18 patients (27.3%) that routinely led to repeat surgery. CONCLUSION: Final fusion after MCGR provides satisfactory additional correction of the main and secondary curves and a moderate increase in the T1-T12 distance but has no impact on sagittal balance and other radiological parameters. The post-operative complication rate is particularly high in patients at risk of complications. LEVEL OF EVIDENCE: Level 4.

Analysis of Growth After Transphyseal Anterior Cruciate Ligament Reconstruction in Children.

BACKGROUND: Pediatric transphyseal anterior cruciate ligament reconstruction (ACLR) bears several advantages and is widely used. The main concern is the risk of growth disturbance. Our purpose was to investigate the incidence and risk factors of growth disturbance in skeletally immature patients who underwent transphyseal ACLR. We hypothesized that this procedure would generate neither clinically relevant limb length discrepancy (LLD) nor axis deviation. METHODS: This prospective, consecutive, single-center series included skeletally immature patients who underwent primary transphyseal ACLR using semitendinosus tendon autograft, with a 2-year follow-up bone length standing radiograph of both lower limbs from pelvis to ankle in anterior posterior view. Lower limb length, mechanical axis deviation (MAD), lateral distal femoral angle (LDFA), and medial proximal tibial angle (MPTA) were measured. The definition of postoperative growth disturbance was defined as ≥10 mm for LLD or ≥3 degrees for axis deviation in comparison to the contralateral lower limb. Predictive variables included age at surgery, gender, side, and diameter of bone tunnels. Student or Mann-Whitney test was used for numerical variables, and Chi-square test or Fisher exact test was used for categorical variables. P values <0.05 were considered statistically significant. RESULTS: Fifty consecutively treated patients were included. Forty-seven patients (31 boys, 16 girls) with a mean age of 13.2 years (range, 9 to 16) at the time of surgery were available for analysis. Six patients had an LLD of at least 10 mm. Twenty-five patients had a difference in MPTA of a least 3 degrees (range, 5 to 8). Sixteen patients had a difference in LDFA of a least 3 degrees (range, 4 to 9). No patients presented with a clinical deformity or related symptoms. Regarding coronal alignment, there was no statistical difference in mechanical axis deviation, LDFA, or MPTA. Gender, side, age, and bone tunnel diameter did not influence growth disturbance. CONCLUSIONS: Transphyseal pediatric ACLR generated a high rate of growth disturbances (leg length discrepancy and axis deviation) although none clinically relevant. Mild proximal tibial axis deviation in patients operated on near skeletal maturity should be further investigated. LEVEL OF EVIDENCE: Level III. STUDY DESIGN: Case-control study.

How does magnetically controlled growing rods insertion affect sagittal alignment in ambulatory early onset scoliosis patients?

PURPOSE: The importance of sagittal alignment restoration in early onset scoliosis (EOS) management has rarely been investigated to date. The aim was to report the influence of magnetically controlled growing rods (MCGR) insertion on the sagittal alignment of EOS patients. METHODS: All consecutive ambulatory patients operated with MCGR rods between 2011 and 2018 were retrospectively included in four institutions. Standing biplanar radiographs were performed preoperatively, in the early postoperative period and at latest follow-up. Global and local sagittal parameters, spinal global shape and harmony were investigated. RESULTS: A total of 37 ambulatory EOS patients were included (mean age at surgery 8.5 (± 2) years). 70% had a balanced construct postoperatively. Both MaxTK (- 17°, p = 0.02) and MaxLL (- 15°, p = 0.001) were significantly reduced, particularly at the instrumented levels. The number of vertebrae included in the lumbar lordosis significantly increased (+ 2 levels, p = 0.02), as well as the thoraco-lumbar inflexion point (+ 2 levels, p < 0.001) and the kyphosis apex (+ 1 level, p < 0.001). Overall mechanical failure rate was 40.5%, and radiological PJK was observed in 43% of the patients, with 11 remaining asymptomatic. Patients with initial hyperkyphosis (> 50°) developed more complications (62% vs. 28%, p = 0.04). CONCLUSION: MCGR insertion flattened the spine in EOS, at both instrumented and non-instrumented levels. Overall spinal harmony was modified, with a cranial shift of the thoraco-lumbar inflexion point and the thoracic kyphosis apex, associated with a lengthening of the lumbar lordosis. The rate of complication remained high, some explanations being found in the radiological changes reported such as the preoperative location of the TK apex. LEVEL OF EVIDENCE: IV.

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.

Arthroscopic Calcaneonavicular Coalition and Too-long Anterior Process of the Calcaneus Resection in Children.

Persistent symptomatic calcaneonavicular coalition (CNC) and too-long anterior process of the calcaneus (TLAP) are congenital disorders that can benefit from surgical treatment. The arthroscopic technique for CNC and TLAP resection has previously been described. The aim of this prospective study was to describe outcomes following arthroscopic resection of 12 (38.71%) CNC and 19 (61.29%) TLAP cases in 30 consecutive pediatric patients treated between July 2009 and March 2013. There mean age was 12.4 (range 10 to 15) years, and the mean follow-up was 55.2 (range 24 to 79) months. Radiographs, American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scores, AOFAS pain scores, and patient satisfaction were assessed. All final postoperative imaging scans revealed complete synostosis resection without recurrence. The mean overall AOFAS Ankle-Hindfoot Score increased from 78.87 (95% confidence interval [CI] 76.74 to 81.01) to 93.06 (95% CI 91.10 to 95.03) (p < .001). All patients showed pain reduction after surgery; even 1 patient (3.23%) who initially developed complex regional pain syndrome eventually had a successful outcome. The mean AOFAS pain score increased from 23.87 (95% CI 22.05 to 25.69) to 34.84 (95% CI 32.97 to 36.70) (p < .001). All patients were either satisfied (n = 9 [30%]) or very satisfied (n = 21 [70%]) with the intervention at the final follow-up. Although both arthroscopic CNC and TLAP resection are demanding techniques, they allow for precise coalition resection through a less invasive approach, which may ultimately lead to faster recovery and improved outcomes.

Evolution of Hip Dysplasia in Pediatric Patients With Prader-Willi Syndrome Treated With Growth Hormone Early in Development.

BACKGROUND: Prader-Willi syndrome (PWS) is a rare genetic disorder characterized by obesity, hypotonia, feeding difficulties, obesity, musculoskeletal manifestations including scoliosis, and hip dysplasia (HD). The aim of this study was to characterize the clinical and radiographic evolution of HD in the pediatric PWS population. METHODS: The authors performed a retrospective cohort study of 72 patients (147 anteroposterior pelvic radiographs) between January 2004 and December 2016. Center-edge angle (CEA) of Wiberg, acetabular index (AI), and neck-shaft angle (NSA) were measures in all hips. The relationship between radiographic and demographic parameters of age, sex, and body mass index z-score (BMIzs) were assessed. RESULTS: A total of 274 radiographic measurements were performed and analyzed in 72 patients. The mean CEA, AI, and NSA were 21.8±7.1 degrees (range, 5 to 35 degrees), 16.7±7 degrees (range, 5 to 45 degrees), and 142±8.5 degrees (range, 128 to 165 degrees), respectively. HD was diagnosed in 79 (29%) hip radiographs and varied significantly between the age groups (P<0.01). A statistically significant association was identified between age and CEA [ß coef, 0.80; 95% confidence interval (CI), 0.6-1; P<0.01], AI (ß coef, -0.90; 95% CI, -1.1 to -0.7; P<0.01), and NSA (ß coef, -1.11; 95% CI, -1.4 to -0.9; P<0.01) angles. Sex and BMIzs were not identified as independent predictors of radiographic hip angles (P>0.1). CONCLUSIONS: The present study demonstrated favorable evolution of hip radiographic parameters in the PWS population treated with growth hormone early in development. This finding should prompt orthopedists to consider observation alone in the management algorithm for HD in patients with PWS. LEVELS OF EVIDENCE: Level III-a retrospective comparative study.

Delayed reconstruction and high BMI z score increase the risk of meniscal tear in paediatric and adolescent anterior cruciate ligament injury.

PURPOSE: The purpose of this study was to identify epidemiologic risk factors for secondary meniscal tears in paediatric and adolescent patients who sustain an anterior cruciate ligament (ACL) tear. The hypothesis was that delayed reconstruction and elevated BMI z score, increase the risk for secondary meniscal tears. METHODS: A prospective, descriptive and analytical study of consecutively accrued children and adolescents with an ACL tear was performed. One hundred and sixty subjects (114 males and 46 females) were identified between 2006 and 2015 at one institution. The age range was between 7 and 19 years. Fifteen parameters were recorded and analysed: age at initial trauma, initial trauma circumstance, sex, BMI z score, affected side, type of sport, Tegner score, athletic level, time to MRI, time to first referral, time to surgery, age at surgery, attempted non-operative treatment, operative report and associated meniscal tear. These meniscal lesions could be diagnosed by an MRI and / or during surgery. RESULTS: Out of the 160 cases, 143 were treated surgically and 17 cases non-operatively. Median corrected BMI z score was 0.5 (range - 1.8 to 4.7). 41.9% had one or more meniscal lesions. 55 patients were initially treated non-operatively, of which 39 patients were secondarily operated. There was a positive relationship between meniscal lesion and: BMI z score (p = 0.0364), attempted non-operative treatment (p = 0.001) and time to surgery (p = 0.002). The median time to ACL reconstruction was 229 days for patients with secondary meniscal lesions. CONCLUSIONS: Patients with ACL tears treated non-operatively developed secondary meniscal lesions requiring delayed surgical management. There was a positive correlation between BMI z score and secondary meniscal lesions. Thus, early ACL reconstruction is advocated in young athletes. LEVEL OF EVIDENCE: Retrospective comparative study, Level III.

Pancreatic fracture: a rare complication following scoliosis surgery.

STUDY DESIGN: Grand Round case report. OBJECTIVE: We report a pancreatic fracture associated with Wirsung duct disruption, following a scoliosis surgery in a cerebral palsy adolescent. Spinal fusion surgery is the standard treatment for severe neuromuscular scoliosis. Many complications such as digestive ones account for its complexity. Postoperative acute pancreatitis is well described, although its pathophysiology remains unclear. To our knowledge, pancreatic fracture following scoliosis correction has never been described to date. Clinical presentation is not specific, and management is not consensual. CASE REPORT: A 14-year-old adolescent had posterior spinal fusion for neuromuscular scoliosis due to cerebral palsy. During the postoperative course, she developed progressive nonspecific abdominal symptoms. The abdominal CT scan demonstrated a pancreatic fracture and a surgical exploration was decided as perforations of the bowel were highly suspected. Drains were placed around the pancreatic area as the retrogastric region was out of reach due to local inflammation. Conservative management led to the occurrence of a pseudocyst in the following weeks as the pancreatic leakage progressively dropped. DISCUSSION: Two hypotheses have been proposed: direct iatrogenic trauma from lumbar pedicle screws and pancreatic rupture related to the correction of the spinal deformity. As the latter seems the most likely, spinal surgeons should be aware of this occurrence following severe scoliosis correction. CONCLUSION: Spinal fusion for severe neuromuscular scoliosis is a difficult procedure, with a high rate of complications. Among them, pancreatic fracture should be considered when abdominal pain persists in the postoperative period. Conservative management is advocated especially in case of a poor general condition.

Gartland types IIB and III supracondylar fractures of the humerus in children: is Blount's method effective and safe?

BACKGROUND: Blount's method is controversial for the treatment of Gartland types IIB and III supracondylar fracture of the humerus (SCFH) in children. The purpose of this study was to evaluate the clinical and radiologic outcomes and the failure and complication rates. METHODS: All types IIB and III SCFH treated with Blount's method from 2003-2013 were included in this retrospective single-center study. Clinical assessment was performed according to Flynn criteria. Baumann angle, anteversion angle, anterior humeral line, and humeroulnar angle were measured for radiographic assessment. RESULTS: Among 447 children with types IIB and III SCHF, 339 were treated according to Blount's method. There were 173 boys (51%), and the mean age was 6.3 years (1-14 years); 71% were type III. Mean time to surgery was 5.7 hours. According to Flynn criteria, results were satisfactory in 91% of cases. No compartment syndrome was encountered. There were 16 (4.7%) secondary displacements requiring surgical revision. Five (1.9%) children developed a cubitus varus deformity. At latest follow-up, the mean Baumann angle was 74.7° (95% confidence interval, 74.1-75.3), the mean anteversion angle was 39.9° (95% confidence interval, 39.5-40.3), the anterior humeral line was normal in 87.6% of cases, and the mean humeroulnar angle was 8.7°. CONCLUSION: Blount's method is appropriate to manage types IIB and III SCFH, provided anatomic and stable reduction is obtained.

Post-trauma scoliosis after conservative treatment of thoracolumbar spinal fracture in children and adolescents: results in 48 patients.

PURPOSE: Authors examined a case series of patients younger than 18 years old who had sustained a traumatic thoracolumbar spine fracture to evaluate radiological and clinical findings of coronal spinal balance, after conservative treatment. METHODS: From 1996 to 2014, a tricentric cohort of 48 patients with an average age of 12 years was radiographically reviewed at 50 months. Cobb angle of fractured vertebra and regional Cobb angle were measured both at baseline and follow-up. Analyses were done according to initial Risser grade, number of fractures and level of injury. RESULTS: There was a total of 11 scoliosis. In group with Risser grade 3 or above, with a single vertebral fracture and lumbar fracture, final regional Cobb angle was statistically higher than initial regional Cobb angle. CONCLUSIONS: The prevalence of scoliosis in our population is higher than those of idiopathic scoliosis; Risser grade 3 or above, lumbar fracture and a single fracture seem to account for more severe coronal deformation.

Spino-pelvic alignment influences disc hydration properties after AIS surgery: a prospective MRI-based study.

PURPOSE: To analyze the disc hydration and volumetric changes of the intervertebral disc after scoliosis surgery depending on the sagittal spino-pelvic organization. METHODS: We conducted a prospective MRI study in 45 patients with surgically treated adolescent idiopathic scoliosis (AIS) with a minimum 2-year follow-up. Fusion ended at L1 (n = 13), L2 (n = 14), L3 (n = 11) or L4 (n = 7). Total disc (Vd) and nucleus volumes (Vn) were extrapolated from 3D reconstruction using a custom-made image processing software (Biomechlab, Toulouse, France). Nucleus and external disc contours were semi-automatically detected on turbo spin echo T2-weighted sequence joined 3-mm sagittal cuts. Disc hydration was extrapolated from the nucleus-disc volume ratio (Vn/Vd). Radiographic sagittal parameters were measured pre- and post-operatively on full spine standing views (pelvic incidence, sacral slope, L1S1 lumbar lordosis). Lumbo-pelvic congruity was calculated by the ratio LL/SS according to Stagnara. RESULTS: Mean PI of the cohort was 55° (34°-85°). After surgical correction, lumbar lordosis was slightly increased by 3° (p = 0.02) decreasing lumbo-pelvic congruity from 1.37 to 1.27 (p < 0.01). When pelvic incidence was less than 55° (mean PI 46°), nucleus volumes have increased on average by 30 % compared to the preoperative status in the unfused lumbar discs, while the total disc volumes has remained stable. Five-year follow-up (n = 13) confirmed the constant improvement of the disc hydration ratio. When PI was high (mean PI 64°), volumetric changes were very mild and significant changes in nucleus volumes and disc hydration ratio concerned only the intermediate lumbar levels (L2L3, L3L4 and L4L5). CONCLUSIONS: This prospective MRI study showed a significant and sustainable improvement in T2 hypersignal of the disc, indirectly indicating improvement of disc hydration content after AIS surgery. Analysis of disc volumetric changes according to the pelvic incidence suggests that these changes are under the influence of the sagittal spino-pelvic alignment. PI seems to play a key role in the homeostasis of the discs under fusion and should be taken into account for preoperative planning. The restoration of the lumbo-pelvic congruence may help to limit early degenerative changes in the free-motion segment discs after AIS surgery. Hydration content was less sensitive to surgery when PI was high, suggesting higher shear stress in the lower discs. Longer follow-up is required to confirm this hypothesis.

Arthroscopic Talocalcaneal Coalition Resection in Children.

PURPOSE: To present the technique and outcomes of arthroscopic talocalcaneal coalition (TCC) resection in pediatric patients. METHODS: We performed a prospective study of 16 consecutive feet with persistent symptomatic TCCs in 15 children. The mean age was 11.8 years (range, 8 to 15 years), and the mean follow-up period was 28 months (range, 12 to 44 months). A posterior arthroscopic TCC resection was performed. The plantar footprint, subtalar motion, pain, and the American Orthopaedic Foot & Ankle Society Ankle-Hindfoot scale score were evaluated preoperatively and postoperatively. Preoperative computed tomography (CT) scans were used to classify the coalition according to the Rozansky classification, to measure the percentage of involvement of the surface area, and to determine the degree of hindfoot valgus. Postoperative CT scans at 1 year (n = 15) and 3 years (n = 5) were used to assess recurrences. Patient satisfaction was also evaluated. RESULTS: The TCC distribution according to the Rozansky classification was type I in 7 cases, type II in 3, type III in 3, and type IV in 3. In all cases the arthroscopic approach enabled complete coalition resection. All patients increased by at least 1 stage in the footprint classification and showed clinical subtalar mobility after surgery. All patients showed a statistically significant improvement in pain after surgery except for 1 patient in whom complex regional pain syndrome developed (P < .001). The mean American Orthopaedic Foot & Ankle Society score was 56.8 (range, 45 to 62) preoperatively versus 90.9 (range, 36 to 100) postoperatively, showing a statistically significant increase (P < .001). Preoperative CT scans showed that all TCCs involved the medial subtalar joint facet, with mean involvement of 40.8% of the articular surface. All postoperative CT scans showed complete synostosis resections with no recurrences at final follow-up. At final follow-up, all patients were either satisfied (n = 4 [27%]) or extremely satisfied (n = 10 [67%]) with the outcome, except the 1 patient (7%) in whom complex regional pain syndrome developed. CONCLUSIONS: Arthroscopic TCC resection provides good outcomes (symptom relief and restoration of subtalar motion), with no recurrence of the coalition. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Use of the Universal Clamp in adolescent idiopathic scoliosis.

UNLABELLED: The Universal Clamp (UC) equipped with a soft sublaminar band is a relatively new thoracic anchor that can be used in hybrid constructs. A dedicated reduction tool that applies traction to the sublaminar band permits gentle translation of the thoracic curve to the pre-contoured fusion rods, which have been previously anchored distally by pedicle screws and proximally by hooks in a claw configuration. METHODS: A literature review concerning the use of UC in adolescent idiopathic Scoliosis was performed. RESULTS: The results confirm the efficacy with the UC hybrid constructs, the good correction (71-66%) of the main thoracic curve and low loss of correction at 2-year follow-up (3-4%). The thoracic curve correction achieved and maintained in the AIS patients appears to be substantially higher than that reported for all hook and hook hybrid techniques. Regardless of the deformity correcting method employed with all-screw constructs, the Cobb angle correction achieved is equivalent to that achieved with UC hybrid devices. Among the present AIS patients who had normal values of thoracic kyphosis pre-operatively, there was almost no change in average thoracic kyphosis at the latest follow-up. However, among the patients with low pre-operative values of T5-T12 kyphosis, the average T5-T12 kyphosis improved. CONCLUSION: Hybrid construct with UC is safe, with reduced operative time and blood loss. While achieving deformity correction in the coronal and axial planes equivalent to the best-reported results of all screw or previous hybrid constructs, the UC hybrid technique appears to provide superior correction in the sagittal plane. The excellent outcome is maintained at the 2-year follow-up.

Ewing sarcoma of the acetabulum in children: a "growth plate-based" surgical strategy.

BACKGROUND: Surgical strategy for Ewing sarcoma (ES) of the pelvis relies on Enneking classification. In adults, in case the acetabulum is involved, excision of the entire acetabulum is needed and often leads to loss of function. In children, the surgeon may adopt a strategy, such as in metaphyseal tumors of long bones where an unaffected growth plate allows a transepiphyseal resection, therefore sparing the joint. METHODS: We present a "triradiate cartilage strategy" for the excision of ES of the pubic component of the acetabulum, which allows a wide resection while preserving most of the socket. The approach is ilioinguinal. Osteotomies of the iliopubic and ischio pubicrami are performed, followed by hip arthrotomy and anterior dislocation. Transacetabular resection is achieved using osteotomes, under image intensifier guidance, with no further reconstruction. Cases are presented for 2 boys aged 6.5 and 9.5 years, treated with chemotherapy and transacetabular resection. RESULTS: Resections were all rated R0. Patient #1 remained asymptomatic, including during sport activities, and had normal hip range of motion at 12-year follow-up. Radiograph demonstrated mild protrusio acetabuli. Patient #2 had no complain at 3-year follow-up with normal hip range of motion, although he presented with an equinus gait. Radiographs demonstrated a well-covered femoral head without medial shift. CONCLUSIONS: A "growth plate-based" surgical strategy can be adapted to malignant pelvic tumors in skeletally immature children. This technique leaves intact the ilio ischiatic component of the triradiate cartilage, which, according to Ponseti, contributes the most to the growth of the acetabulum. Joint sparing improves the functional result and decreases the risk of complication. LEVEL OF EVIDENCE: IV.

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.

No osteolysis at the telescopic junction of 128 FITBONE lengthening nails.

BACKGROUND: Motorized lengthening nails are the treatment standard for bone lengthening of the lower limbs. However, bony changes namely osteolysis and periosteal hypertrophy have been described after certain type of magnetically driven lengthening nails. The aim of this study was to estimate the proportion rate of radiological bone abnormalities of Fitbone TAA femoral or tibial lengthening nails with a minimum follow-up time of 1 year. HYPOTHESIS: The bone surrounding the telescopic junction of Fitbone lengthening nails does not exhibit osteolysis or periosteal reactions. The bone surrounding the locking screws exhibits cortical hypertrophy. PATIENTS AND METHODS: Single-centre retrospective case series of patients treated with a Fitbone nails with a minimum follow-up of 1 year after implantation. Standard orthogonal radiographs were obtained postoperatively, weekly during the distraction phase, and then monthly for 6 months, and before removal of the equipment. We looked for bone abnormalities at the telescoping junction of the nail and at the locking screws before removal. RESULTS: In total, 101 patients (58 males, 43 females) with a mean age of 21 years (range: 11.8-53.5) had 128 (101 femoral and 27 tibial) limb lengthening nails implanted between 2010 and 2021. The mean follow-up period was 925 days (range: 371-3587). The mean lengthening was 4.7cm (range: 1.5-8.0). No bones exhibited focal osteolysis or periosteal reactions at the telescopic junction of the lengthening nail. Cortical hypertrophy at the locking screws was observed in significantly more Fitbone nails than previously reported, i.e., 101/128 (79%). DISCUSSION: Neither focal osteolysis, nor periosteal reactions were observed at the bone surrounding the telescopic junction of 128 Fitbone lengthening nails. Cortical hypertrophy around the single diaphyseal locking screw was observed in 101/128 (79%) of the cases. These absences of osteolytic changes after long term observation are reassuring for both surgeons and patients alike. LEVEL OF EVIDENCE: IV.

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.