Defining threshold for sagittal correction in lumbar fractures.

PURPOSE: Surgical indications for thoraco-lumbar fractures are driven both by neurological status, fractures instability and kyphotic deformity. Regarding kyphotic deformity, an angulation superior to 20° is considered by many surgeons as a surgical indication to reduce the disability induced by post-traumatic kyphosis. However, there is a lack of data reporting the ideal or theoretical lordosis that one must have in a particular lumbar segment on CT-scan. The main goal of this study was to determine the mean value for segmental lumbar lordosis according to pelvic incidence (PI) on a cohort of normal subjects. METHODS: The consecutive CT-scan of 171 normal adult subjects were retrospectively analyzed. The PI and the segmental lordosis (L4S1, L3L5, L2L4, L3L1, L2T12 and T11-L1) were measured on all CT-scan. The mean values were calculated for the global cohort and a sub-group analysis according to IP ranges (< 45°, 45 < IP < 60° and > 60°) was performed. RESULTS: The mean angular values for the whole cohort were IP: 54, 9°; L4S1: - 38, 1°; L3L5: - 30, 6°; L2L4: - 14, 1°; L1L3: - 4, 9°; T12L2: + 1, 9° and T11L1: + 5, 4°. The segmental values vary significatively with PI ranges, as for L3L5: - 26, 8° (PI < 45°); - 30° (45 < PI < 60°) and - 35, 1° (PI > 60°). CONCLUSION: These results provide a referential of theoretical values of segmental lordosis according to PI. This abacus may help spinal surgeon in their decision-making process regarding lumbar fractures, to determine the amount of sagittal correction needed, according to the PI range, to be adapted to the sagittal morphology of the patient. LEVEL OF EVIDENCE: III.

Assessment of malalignment at early stage in adolescent idiopathic scoliosis: a longitudinal cohort study.

INTRODUCTION: Our objective was to assess abnormalities of the odontoid-hip axis (OD-HA) angle in a mild scoliotic population to determine whether screening for malalignment would help predict the distinction between progressive and stable adolescent idiopathic scoliosis (AIS) at early stage. MATERIALS AND METHODS: All patients (non-scoliotic and AIS) underwent a biplanar X-ray between 2013 and 2020. In AIS, inclusion criteria were Cobb angle between 10° and 25°; Risser sign lower than 3; age higher than 10 years; and no previous treatment. A 3D spine reconstruction was performed, and the OD-HA was computed automatically. A reference corridor for OD-HA values in non-scoliotic subjects was calculated as the range [5th-95th percentiles]. A severity index, helping to distinguish stable and progressive AIS, was calculated and weighted according to the OD-HA value. RESULTS: Eighty-three non-scoliotic and 205 AIS were included. The mean coronal and sagittal OD-HA angles in the non-scoliotic group were 0.2° and -2.5°, whereas in AIS values were 0.3° and -0.8°, respectively. For coronal and sagittal OD-HA, 27.5% and 26.8% of AIS were outside the reference corridor compared with 10.8% in non-scoliotic (OR = 3.1 and 3). Adding to the severity index a weighting factor based on coronal OD-HA, for thoracic scoliosis, improved the positive predictive value by 9% and the specificity by 13%. CONCLUSION: Analysis of OD-HA suggests that AIS patients are almost three times more likely to have malalignment compared with a non-scoliotic population. Furthermore, analysis of coronal OD-HA is promising to help the clinician distinguish between stable and progressive thoracic scoliosis.

The Ankle Ligament Reconstruction-Return to Sport after Injury (ALR-RSI) is a valid and reliable measure to assess psychological readiness before returning to sport following peroneal tendon pathology surgery.

PURPOSE: The objective of this study was to validate a scale that could help surgeons evaluate patients' psychological readiness to return to sport (RTS) after peroneal tendon pathology surgery. METHODS: The Ankle Ligament Reconstruction-Return to Sport after Injury (ALR-RSI) scale, which had previously been validated in ankle ligament reconstruction patients, was adapted to evaluate the psychological preparedness for RTS in athletic patients who underwent peroneal tendinopathy surgery. The Foot and Ankle Outcome Score (FAOS) and Foot Ankle Ability Measurement (FAAM) scores were employed as patient-related outcome measurement (PROM) instruments. RESULTS: This study included 57 patients. There was a strong correlation between ALR-RSI and both FAOS and FAAM (r = -0.68 and 0.74, respectively). ALR-RSI was considerably higher in patients who returned to sports than in those who did not. The mean score was 72.9 ± 19.0 in patients who returned to the same preinjury level, 48.5 ± 24.0 in those who returned to a lower level and 53.6 ± 31.1 in patients who changed their athletic activity (p < 0.0001). Furthermore, ALR-RSI showed at least a similar discrimination ability when compared to FAOS and FAAM. The test-retest intraclass correlation coefficient was 0.95. The Cronbach's α statistic used to measure the internal consistency was high (0.95). A Youden index of 0.65 was observed for a cut-off score of 68 points. CONCLUSION: ALR-RSI is a valid instrument for assessing psychological readiness to RTS in an athletic population following peroneal tendon surgery. When compared to the most commonly used PROMs, it was strongly correlated and demonstrated at least similar discrimination capacity. This could assist surgeons in identifying athletes who will have poor postoperative results and advising them on their capability to RTS. LEVEL OF EVIDENCE: Level III.

Validation of the Ankle Ligament Reconstruction-Return to Sports after Injury (ALR-RSI) Score as a Tool to Assess Psychological Readiness to Return to Sport in an Active Population After Ankle Fracture Surgery: A Cross-sectional Study.

Ankle injuries account for 15% to 25% of all sports injuries resulting in significant pain and loss of function. The purpose of this cross-sectional study was to validate a scale to help surgeons quantify the psychological readiness to Return To Sport (RTS) in patients undergoing ankle fracture surgery. ALR-RSI was used to assess the psychological readiness for RTS in athletic patients who underwent ankle fracture fixation between January 2020 and January 2021. Participants filled out ALR-RSI and 2 Patient-Related Outcome Measurement (PROM) tools: Olerud-Molander Ankle Score (OMAS) and Self-Reported Foot and Ankle Score (SEFAS). A total of 93 patients were included. There was a strong correlation between ALR-RSI and both OMAS and SEFAS, with Pearson coefficients of r = 0.58 and 0.53, respectively. ALR-RSI was significantly higher in the RTS group than in those who no longer practiced their main preinjury sport. Moreover, the discriminant validity of ALR-RSI (AUC = 0.81) was better than that of the SEFAS and OMAS (AUC = 0.64 and 0.65, respectively, p = .001). The intra-class correlation coefficient ρ of 0.94 showed excellent reproducibility. At an optimal cutoff value of 76.7, ALR-RSI had a sensitivity of 81% and a specificity of 75% with a Youden index of 0.56. In conclusion, ALR-RSI was a valid and reproducible tool to evaluate the psychological readiness for RTS in an active population after an ankle fracture. This score could help surgeons identify athletes who may have unfavorable postoperative outcomes and provide support on the ability to RTS.

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.

Clinical and radiographic evolution of graduate patients treated with magnetically controlled growing rods: results of a French multicentre study of 90 patients.

PURPOSE: The purpose of this study was to investigate patients with early-onset scoliosis (EOS) who completed their electromagnetic lengthening rod program to assess the demographics of this population and to analyze the evolution of clinical and radiological parameters and the occurrence of complications. METHODS: This was a multicenter study with 10 French centers. We collected all patients with EOS who had undergone electromagnetic lengthening between 2011 and 2022. They had to have reached the end of the procedure (graduate). RESULTS: A total of 90 graduate patients were included. The mean follow-up time over the entire period was 66 months (25.3-109). Of these, only 66 patients (73.3%) underwent definitive spinal arthrodesis at the end of the lengthening phase, whereas 24 patients (26.7%) kept their hardware in situ with a mean follow-up time from the last lengthening of 25 months (3-68). Patients had an average of 2.6 surgeries (1-5) over the entire follow-up. Patients had an average of 7.9 lengthenings for a mean total lengthening of 26.9 mm (4-75). Analysis of the radiological parameters showed a percentage reduction in the main curve of 12 to 40%, depending on the etiology, with an average reduction of 73-44°, and an average thoracic height of 210 mm (171-214) for an average improvement of 31 mm (23-43). There was no significant difference in the sagittal parameters. During the lengthening phase, there were a total of 56 complications in 43 patients (43.9%; n = 56/98), of which 39 in 28 patients (28.6%) resulted in unplanned surgery. In the graduate patients, there were a total of 26 complications in 20 patients (22.2%), all of which resulted in unscheduled surgery. CONCLUSION: MCGR, allow to decrease the number of surgeries, to progressively improve the scoliotic deformity and to reach a satisfactory thoracic height at the price of an important complication rate linked in particular to the complexity of the management of patients with an EOS.

The interosseous tuberosities of the forearm exist from 1-year-old: a pediatric radiological study describing the ages of appearance of the different forearm reliefs.

PURPOSE: Interosseous tuberosities have been described in adults on the radial and ulnar sides. However, their presence at birth and their development during growth is still unknown. The objective of this work is to establish the age of onset of this tuberosity among a cohort of children aged 1-year-old or older. METHODS: All anterior-posterior and lateral radiographs performed in our hospital during a consecutive period of 6 months were retrospectively analyzed. Exclusion criteria were: presence of a fracture, a tumor, an age higher than 16 years, radiograph not performed strictly from the front with supination or from the side. On the anterior-posterior radiograph, the presence of the following structures was sought: radial interosseous tuberosity and determination of its length and width; the appearance of the epiphyseal nucleus of the radial head, of the bicipital tuberosity, and of the distal epiphysis. On the lateral views, the presence of the following structures was sought: ulnar interosseous tuberosity and determination of its length and width; the appearance of the olecranon epiphyseal nucleus, and the distal epiphysis. RESULTS: Over the review period, anterior-posterior and lateral radiographs were performed on 368 consecutive children. Finally, 179 patients were included in the radiographic analysis. The radial and ulnar interosseous tuberosities and bicipital tuberosity were present in all cases, from 1-year-old. Only the distal radial epiphysis began to appear at the age of one year, the others ossifying progressively during growth. CONCLUSION: Tuberositas interossea ulnarii and radii exists, are present from 1-year-old and continue to develop during growth.

Intraoperative Optical Monitoring of Spinal Cord Hemodynamics Using Multiwavelength Imaging System.

The spinal cord is a major structure of the central nervous system allowing, among other things, the transmission of afferent sensory and efferent motor information. During spinal surgery, such as scoliosis correction, this structure can be damaged, resulting in major neurological damage to the patient. To date, there is no direct way to monitor the oxygenation of the spinal cord intraoperatively to reflect its vitality. This is essential information that would allow surgeons to adapt their procedure in case of ischemic suffering of the spinal cord. We report the development of a specific device to monitor the functional status of biological tissues with high resolution. The device, operating with multiple wavelengths, uses Near-InfraRed Spectroscopy (NIRS) in combination with other additional sensors, including ElectroNeuroGraphy (ENG). In this paper, we focused primarily on aspects of the PhotoPlethysmoGram (PPG), emanating from four different light sources to show in real time and record biological signals from the spinal cord in transmission and reflection modes. This multispectral system was successfully tested in in vivo experiments on the spinal cord of a pig for specific medical applications.

Anatomical and biomechanical study of the inferior extensor retinaculum by shear-wave elastography in healthy adults.

PURPOSE: The purpose of this study was to evaluate the stiffness of the inferior extensor retinaculum (IER) using shear-wave elastography (SWE) in neutral and varus positions in healthy adults, and to assess the reliability and reproducibility of these measurements. METHODS: Both ankles were analyzed by shear-wave elastography (SWE) in 20 healthy patients (10 females/10 males) resting on a hinge support with their ankles in neutral, valgus 20°, and varus 30° positions. Their stiffness was evaluated by shear-wave speed measured (SWS). RESULTS: The median SWS of the IER varies according to the position of the ankle. The IER tension was maximal in the 20° valgus position (4.1 m/s (52.8 kPa), ranged from 3.0 to 6.4 m/s), in contrast to the other positions (p < 0.0001). Retinaculum SWS was negatively correlated with age significantly in neutral (ρ = - 0.38, p = 0.02) and varus (ρ = - 0.47, p = 0.002) positions. Gender, dominant side, height, and foot morphology (foot arch, hind foot frontal deviation) had no impact on IER stiffness. Intra- and inter-observer agreements were all excellent. CONCLUSION: SWE is a reliable and reproducible technique for quantitative analysis of the stiffness of the main part of the IER: the frondiform ligament. It becomes taut in the valgus position of the ankle, and its strength decreases with age, even in young subjects. This could be an interesting diagnostic examination in cases of prolonged pain, and could help in the choice of transplant during surgical repair of the ATFL. LEVEL OF EVIDENCE: IV.

Induced-Membrane Reconstruction After Calcaneum's Ewing Sarcoma in Children: A Report of 3 Cases.

Calcaneus's Ewing sarcoma is a rare location with a poor prognosis and remains challenging for tumor surgery. We present 3 cases of calcaneus resection for Ewing sarcoma in children and its reconstruction managed by induced-membrane technique. To our knowledge, this technique has never been published for hindfoot's tumor management. Three children (aged from 9 to 14 years) had partial or total resection of calcaneus initially replaced by a cement spacer. The second step consisted of removing the cement and filling the membrane cavity with autograft taken from the ipsilateral iliac crest, potentially combined with bone substitute. In the meantime, children received chemotherapy and possibly radiotherapy according to the Euro E.W.I.N.G. 99 protocol. It was possible to optimize bone formation as we carried out the bone grafting procedure sometime after the treatments. In one case, the evolution was marked by local septic complication, 9 months after resection, and by tumor recurrence in presacral soft tissues treated with radiotherapy and chemotherapy. Partial weightbearing was allowed after 6 weeks of cast, under the protection of a splint. Graft consolidation was achieved at a median of 3.2 months (3-3.5) for all. After a median follow-up of 9 years (5-13), all preserved their limb and were considered in remission. The 3 children reached adulthood, with a median age of 21 years (19-24.8). At last follow-up, median Musculoskeletal Tumor Score was 73% (63-87), and median American Orthopaedic Foot and Ankle Society hind foot score was 78 (72-87).

Ankle syndesmosis biomechanical evaluation by shear-waves elastography in healthy young adults: Assessment of the reliability and accuracy of the measurements and definition of a corridor of normality.

BACKGROUND: Aims of this study were: 1/ to evaluate the shear wave speed (SWS) properties of the anteroinferior tibiofibular ligament (AITFL) and the distal interosseous membrane (DIOM) in neutral, dorsal flexion and plantar flexion positions in a cohort of healthy adult volunteers; 2/ to assess the reliability and reproducibility of these measurements. METHODS: Both ankles were analyzed by shear wave elastography (SWE) in 20 healthy patients (10 females/10 males) standing on a hinge support with their ankles in neutral, 20° dorsal flexion and 30° plantar flexion positions. Stiffness of AITFL and DIOM was evaluated by SWS measurement. RESULTS: The SWS of AITFL and DIOM were minimal in the plantar flexion position (4.28 m/s [2.65-5.11] and 3.35 m/s [1.69-4.55], respectively). It increased significantly for both ligaments in neutral position (4.69 m/s [3.53-5.71] and 3.81 m/s [1.91-4.74], respectively; p < 0.0001), and reached their maximum values in dorsal flexion (6.58 m/s [5.23-8.34] and 4.79 m/s [3.07-6.19], respectively; p < 0.0001). There was no correlation between each ligament regardless the positions. SWS of AITFL was independent of demographic characteristics analyzed. SWS of DIOM was negatively correlated with height in dorsal flexion (ρ = -0.35; p = 0.03) and in plantar flexion (ρ = -0.37; p = 0.02). Female gender was associated with increased DIOM SWS in neutral (p = 0.005), dorsal flexion (p = 0.003), and plantar flexion (p = 0.001) positions. Moreover, foot morphology (foot arch, hind foot frontal deviation) did not impact AITFL nor DIOM SWS. Inter- and intra-observer measurements were all good or excellent. CONCLUSION: The AITFL and DIOM, stabilizers of the distal tibiofibular syndesmosis, increase in stiffness while dorsal flexion increases. This study describes a reliable and reproducible protocol to assess their stiffness by SWE, and defines a corridor of normality.

Surgical treatment in child's congenital toe syndactyly: Risk factor of recurrence, complication and poor clinical outcomes.

INTRODUCTION: Surgical treatment of toe syndactyly remains controversial. The strong demand from parents for a cosmetic release is increasing in our societies. But is it worth it? The objective was to assess medium-long term outcomes and to identify the risk factors of recurrence, complication and poor clinical outcomes. METHODS: Sixty-eight toe syndactylies (38 patients) undergoing surgery between 2008 and 2017 with a follow-up higher than two years were included consecutively and retrospectively. Four children (four syndactylies) were lost to follow-up and excluded. The mean age of the first surgery was 3.9 years old (0.8-16.7) and cohort mean follow-up was 6.9 years (2.8-11.2). In all patients, web release with a commissural dorsal flap was performed and associated a cutaneous resurfacing (spontaneous epithelialization, full-thickness skin graft taken from the popliteal crease, or a hyaluronic acid ester matrix). RESULTS: Eighteen syndactylies (28.1%) in 14 patients recurred and one syndactyly required revision surgery. An age of surgery above two years was the only risk factor for recurrence found in univariate (OD = 0.27[0.08;0.85];p = 0.02) and multivariate studies (IC 95% = 0.05-0.68;p = 0.02). Seven complications (11.7%) in seven syndactylies (6 patients) were reported with six keloids (9.4%) and one scar retraction (1.6%). Each complication underwent an additional procedure. African ethnicity (N = 15) represents a risk factor (N = 4/15; OD = 0.12[0.009;0.97];p = 0.02) for keloids formation. Withey's average score is 4.9 (1-11), mean OxAFQ-C score was 52/60 (30-60), 67% would repeat the surgery and 69% felt satisfied at last follow-up. The simple syndactyly would appear less satisfied than complex or complicated (p = 0.02). CONCLUSIONS: Surgical treatment of child's congenital syndactyly involves a risk of recurrence (28%) and potential complications (11,7%). Performed surgical procedure over two years old increase the risk of recurrence. African ethnicity is a risk factor in scarring complication. Only half of simple syndactylies are satisfied and prone to repeat the surgery.

Effect of curve location on the severity index for adolescent idiopathic scoliosis: a longitudinal cohort study.

OBJECTIVES: Adolescent idiopathic scoliosis (AIS) is the most common spinal disorder in children. A severity index was recently proposed to identify the stable from the progressive scoliosis at the first standardized biplanar radiographic exam. The aim of this work was to extend the validation of the severity index and to determine if curve location influences its predictive capabilities. METHODS: AIS patients with Cobb angle between 10° and 25°, Risser 0-2, and no previous treatment were included. They underwent standing biplanar radiography and 3D reconstruction of the spine and pelvis, which allowed to calculate their severity index. Patients were grouped by curve location (thoracic, thoracolumbar, lumbar). Patients were followed up until skeletal maturity (Risser ≥ 3) or brace prescription. Their outcome was compared to the prediction made by the severity index. RESULTS: In total, 205 AIS patients were included; 82% of them (155/189, 95% confidence interval [74-90%]) were correctly classified by the index, while 16 patients were unclassified. Positive predictive ratio was 78% and negative predictive ratio was 86%. Specificity (78%) was not significantly affected by curve location, while patients with thoracic and lumbar curves showed higher sensitivity (≥ 89%) than those with thoracolumbar curves (74%). CONCLUSIONS: In this multicentric cohort of 205 patients, the severity index was used to predict the risk of progression from mild to moderate scoliosis, with similar results of typical major curve types. This index represents a novel tool to aid the clinician and the patient in the modulation of the follow-up and, for progressive patients, their decision for brace treatment. KEY POINTS: • The severity index of adolescent idiopathic scoliosis has the potential to detect patients with progressive scoliosis as early as the first exam. • Out of 205 patients, 82% were correctly classified as either stable or progressive by the severity index. • The location of the main curve had small effect on the predictive capability of the index.

Shear wave elastography of lumbar annulus fibrosus in adolescent idiopathic scoliosis before and after surgical intervention.

OBJECTIVES: To determine lumbar intervertebral disc properties with shear wave elastography in adolescent idiopathic scoliotic (AIS) patients before and after surgery, and compare them with asymptomatic controls. METHODS: Twenty-five severe AIS patients with an indication for fusion surgery (15 ± 1.5 years old, the Cobb angle ranging between 40 and 93°) and fifty-nine asymptomatic adolescents (13 ± 2 years old) were included prospectively. Shear wave speed (SWS) was measured in the annulus fibrosus of L3-L4, L4-L5, and L5-S1 discs of each subject. In AIS patients, measurements took place before surgery, and 3 months (N = 13) or 1 year after (N = 12). RESULTS: No difference was observed between disc levels in any group. When pooling disc levels, SWS was significantly higher in preop AIS patients (4.0 ± 0.5 m/s) than in asymptomatic subjects (3.1 ± 0.5 m/s, p < 0.0001). SWS decreased 3 months postop (3.5 ± 0.3 m/s), and it decreased further towards normal values 1 year after (3.3 ± 0.4 m/s). SWS in preop AIS patients tended to decrease with the Cobb angle (Spearman's rho = - 0.4, p = 0.05). CONCLUSION: Shear wave elastography measurements showed that discs in AIS patients were altered relative to asymptomatic ones, and this alteration tended to normalize 1 year post fusion surgery. Further studies should aim at determining if bracing of mild scoliosis has an effect on disc properties. KEY POINTS: • Shear wave elastography shows alteration of annulus fibrosus in adolescent idiopathic scoliosis. • Disc elastography tends to normalize 1 year after surgery.

Spine slenderness and wedging in adolescent idiopathic scoliosis and in asymptomatic population: an observational retrospective study.

PURPOSE: The origin of the deformity due to adolescent idiopathic scoliosis (AIS) is not known, but mechanical instability of the spine could be involved in its progression. Spine slenderness (the ratio of vertebral height to transversal size) could facilitate this instability, thus playing a role in scoliosis progression. The purpose of this work was to investigate slenderness and wedging of vertebrae and intervertebral discs in AIS patients, relative to their curve topology and to the morphology of control subjects. METHODS: A total of 321 AIS patients (272 girls, 14 ± 2 years old, median Risser sign 3, Cobb angle 35° ± 18°) and 83 controls were retrospectively included (56 girls, median Risser 2, 14 ± 3 years). Standing biplanar radiography and 3D reconstruction of the spine were performed. Geometrical features were computed: spinal length, vertebral and disc sizes, slenderness ratio, frontal and sagittal wedging angles. Measurement reproducibility was evaluated. RESULTS: AIS girls before 11 years of age had slightly longer spines than controls (p = 0.04, Mann-Whitney test). AIS vertebrae were significantly more slender than controls at almost all levels, almost independently of topology. Frontal wedging of apical vertebrae was higher in AIS, as expected, but also lower junctional discs showed higher wedging than controls. CONCLUSION: AIS patients showed more slender spines than the asymptomatic population. Analysis of wedging suggests that lower junctional discs and apex vertebra could be locations of mechanical instability. Numerical simulation and longitudinal clinical follow-up of patients could clarify the impact of wedging, slenderness and growth on the biomechanics of scoliosis progression. These slides can be retrieved under Electronic Supplementary Material.

Rib Cage Measurement Reproducibility Using Biplanar Stereoradiographic 3D Reconstructions in Adolescent Idiopathic Scoliosis.

BACKGROUND: A reproducibility study of preoperative rib cage three-dimensional (3D) measurements was conducted for patients with Adolescent Idiopathic Scoliosis (AIS). No prior reliability study has been performed for preoperative 3D reconstructions of the rib cage by using stereoradiography in patients with preoperative AIS. Our objective was to assess the reliability of rib cage 3D reconstructions using biplanar stereoradiography in patients with AIS before surgery. METHODS: This series includes 21 patients with Lenke 1 or 2 scoliosis (74±20 degrees). All patients underwent low-dose standing biplanar radiographs. Two operators performed reconstructions twice each. Intraoperator repeatability, interoperator reproducibility, and intraclass coefficients (ICC) were calculated and compared between groups. RESULTS: The average rib cage volume was 4.71 L (SD±0.75 L). Two SD was 0.19 L with a coefficient of variation of 4.1%; ICC was 0.968. The thoracic index was 0.6 (SD±0.1). Two SD was 0.03 with a coefficient of variation of 4.7% and a ICC of 0.820. As for the Spinal Penetration Index (6.4%; SD±2.4), 2SD was 0.9% with a coefficient of variation of 14.3% and a ICC of 0.901. The 3D rib hump 2SD (average 27±8 degrees) was 1.4 degrees. The coefficient of variation and ICC were respectively 5.1% and 0.991. CONCLUSIONS: Three-dimensional reconstruction of the rib cage using biplanar stereoradiography is a reliable method to estimate preoperative thoracic parameters in patients with AIS. LEVEL OF EVIDENCE: Level IV-diagnostic study.

Early Ultrasound Follow-Up of Extension-Type Supracondylar Fractures Treated by the Collar-and-Cuff (Blount) Technique.

BACKGROUND: Extension-type supracondylar fractures can be treated with external immobilization, with the elbow flexed 100°. However, this technique requires early evaluation by true lateral x-ray of the elbow to detect secondary fracture displacement. QUESTIONS/PURPOSE: The purpose of this work is to evaluate whether ultrasound imaging is suitable for demonstrating initial reduction of supracondylar fractures and early secondary displacement of the fracture. METHODS: Fourteen patients aged 3 to 7 years (mean, 4.8 years) were treated by closed reduction under general anesthesia and immobilization with a collar and cuff. All patients had early postoperative x-rays and ultrasonography on day 1, as well as day 8 x-rays and ultrasonography. Ultrasonograms were performed by an experienced senior radiologist. RESULTS: In all cases, a complete reduction was confirmed at initial follow-up on both sonogram and intraoperative fluoroscopy. In 13 of 14 cases, no secondary displacement of the fracture was noted at day 8 on either ultrasonography or x-ray images. In 1 case, a secondary displacement was noted at day 8 on ultrasonography and confirmed by the lateral x-ray. CONCLUSIONS: Our study found a complete agreement assessing the quality of intraoperative reduction of supracondylar fractures by radiographs and ultrasonography. These results confirm that ultrasound imaging is suitable for demonstrating secondary displacements of supracondylar fractures in children. We postulate that in Gartland types II and III fractures treated by Blount procedure, a negative ultrasound result at day 8 follow-up may reduce the need for further radiographs. However, in any doubtful situation, the need for conventional radiographs remains. LEVEL OF EVIDENCE: Diagnostic study, level II.

A reduced micro-dose protocol for 3D reconstruction of the spine in children with scoliosis: results of a phantom-based and clinically validated study using stereo-radiography.

PURPOSE: The aim of this study was to validate the reproducibility of 3D reconstructions of the spine using a new reduced micro-dose protocol. METHODS: First, semi-quantitative image analysis was performed using an anthropomorphic child phantom undergoing low-dose biplanar radiography. This analysis was used to establish a "lowest dose" allowing for acceptable visibility of spinal landmarks. Subsequently, a group of 18 scoliotic children, 12 years of age or younger, underwent full-spine biplanar radiography with both micro-dose and the newly defined reduced micro-dose. An intra- and inter-observer reliability study of 3D reconstructions of the spine was performed according to the International Organization for Standardization (ISO)-5725 standard, with three operators. RESULTS: The reduced micro-dose setting corresponded to a theoretical reduction of radiation dose exposure of approximately 58%. In vivo results showed acceptable intra- and inter-observer reliability (for instance, 3.8° uncertainty on Cobb angle), comparable to previous studies on 3D spine reconstruction reliability and reproducibility based on stereo-radiography. CONCLUSION: A new reduced micro-dose protocol offered reliable 3D reconstructions of the spine in patients with mild scoliosis. However, the quality of 3D reconstructions from both reduced micro-dose and micro-dose was inferior to standard-dose protocol on most parameters. Standard-dose protocol remains the option of choice for most accurate assessment and 3D reconstruction of the spine. Still, this new protocol offers a preliminary screening option and a follow-up tool for children with mild scoliosis yielding extremely low radiation and could replace micro-dose protocol for these patients. KEY POINTS: • We investigated the reliability of 3D reconstructions of the spine based on a new stereo-radiography protocol reducing radiation dose by 58% compared with established micro-dose imaging protocol. • The new reduced micro-dose protocol offers a reproducible preliminary screening option and a follow-up tool in the necessarily frequent repeat imaging of children with mild scoliosis yielding extremely low radiation and could replace existing micro-dose protocol for these patients. • EOS standard-dose protocol remains the option of choice for exact radiographic assessment of scoliosis, offering more exact 3D reproducibility of the spine compared to both micro-dose and the new reduced micro-dose protocols.

Bone and joint infections in infants under three months of age.

AIM: Studies on bone and joint infections (BJI) in infants under three months are rare. We described the clinical and paraclinical features and outcomes of infants hospitalised with BJI under three months of age. METHODS: The French National Hospital Discharge Database provided data on BJIs in infants under three months of age from January 2004 to 2015 in three Parisian Paediatric teaching hospitals. RESULTS: We included 71 infants under three months of age with BJI, the median age was 25 days, and the interquartile range (IQR) was 17-43 days. The most common infection sites were the hip (32%) and knee (32%). Symptoms included pain (94%), limited mobility (87%) and/or fever (52%). There were 11 (15.5%) cases of nosocomial BJI. A pathogen was identified in 51 infants (71.8%), including Streptococcus agalactiae (45%), Staphylococcus aureus (22%) and Escherichia coli (18%). The initial median C-reactive protein test rate was 31 mg/L (IQR 17-68). Of the 34 infants followed for more than one year, four developed severe orthopaedic conditions such as epiphysiodesis, limb length discrepancy, bone necrosis and/or impaired limb function. CONCLUSION: Streptococcus agalactiae was the most common cause of BJI in infants under three months. Orthopaedic sequelae were rare, but severe, and required long-term follow-up.

Head to pelvis alignment of adolescent idiopathic scoliosis patients both in and out of brace.

PURPOSE: To determine the short-term effect of bracing of adolescent idiopathic scoliotic (AIS) patients on the relationships between spinopelvic parameters related to balance, by comparing their in and out-of-brace geometry and versus healthy subjects. METHODS: Forty-two AIS patients (Cobb angle 29° ± 12°, ranging from 16° to 61°) with a prescription of orthotic treatment were included retrospectively and prospectively. They all underwent biplanar radiography and 3D reconstruction of the spine and pelvis before bracing as well as less than 9 months after bracing. Eighty-three age-matched healthy adolescents were also included as control group and underwent biplanar radiography and 3D reconstruction. RESULTS: Sacral slope was higher in AIS than healthy patients (p = 0.005). Bracing induced large changes of pelvic tilt (between - 9° and 9°), although patients' sagittal spinopelvic alignment tended to remain within the normality corridors defined by the healthy patients. Patients had flatter backs compared to healthy subjects and bracing further reduced their spinal curves. The head tended to remain above the pelvis in-brace. CONCLUSION: Analysis of sagittal alignment from head to pelvis showed that bracing further flattened the patients' backs and induced large compensating reorientations of the pelvis. Sagittal balance should be included in the planning and evaluation of brace treatment, since it could play a role in its outcome. These slides can be retrieved under Electronic Supplementary Material.