Shorter and sweeter: the 16-item version of the SRS questionnaire shows better structural validity than the 20-item version in young patients with spinal deformity.

PURPOSE: In patients with adult spinal deformity, it was previously shown that 16 of the non-management items of the SRS-instrument showed a better fit to the theoretical four-factor model (pain, function, self-image, mental health) than did all 20 items. Whether the same phenomenon is observed in data from younger (< 20y) patients, for whom the questionnaire was originally designed, is not currently known. METHODS: Confirmatory factor analysis was used to evaluate the factor structure of the 20 non-management items of the SRS-instrument completed by 3618 young patients with spinal deformity (75.5% female; mean age, 15.0 ± 2.0 years) and of its equivalence across language versions (2713 English-speaking, 270 Spanish, 264 German, 223 Italian, and 148 French). The root mean square error of approximation (RMSEA) and comparative fit index (CFI) indicated model fit. RESULTS: Compared with the 20-item version, the 16-item solution significantly increased the fit (p < 0.001) across all language versions, to achieve good model fit (CFI = 0.96, RMSEA = 0.06). For both 16-item and 20-item models, equivalence across languages was not reached, with some items showing weaker item-loading for some languages, in particular German and French. CONCLUSION: In patients with adolescent idiopathic scoliosis, the shorter 16-item version showed a better fit to the intended 4-factor structure of the SRS-instrument. The wording of some of the items, and/or their equivalence across language versions, may need to be addressed. Questionnaire completion can be a burden for patients; if a shorter, more structurally valid version is available, its use should be encouraged.

Outcomes of growing rod surgery for severe compared with moderate early-onset scoliosis: a matched comparative study.

Aims: The aim of this study was to compare the outcomes of surgery using growing rods in patients with severe versus moderate early-onset scoliosis (EOS). Patients and Methods: A review of a multicentre EOS database identified 107 children with severe EOS (major curve ≥ 90°) treated with growing rods before the age of ten years with a minimum follow-up of two years and three or more lengthening procedures. From the same database, 107 matched controls with moderate EOS were identified. Results: The mean preoperative major curve was 101° (90 to 139) in the severe group and 67° (33° to 88°) in the moderate group (p < 0.001), which was corrected at final follow-up to 57° (10° to 96°) in the severe group and 40° (3° to 85°) in the moderate group (p < 0.001). T1-S1 height increased by a mean of 54 mm (-8 to 131) in the severe group and 27 mm (-4 to 131) in the moderate group at the initial surgery (p < 0.001), and by 50 mm (-17 to 200) and 54 mm (-11 to 212), respectively, during distraction (p = 0.84). The mean number of complications per patient was 2.6 (0 to 14) in the severe group and 1.9 (0 to 10) in the moderate group (p = 0.040). Five patients (4.7%) in the severe group and three (2.8%) in the moderate group developed a neurological deficit postoperatively (p = 0.47). Conclusion: Severe EOS can be treated effectively using growing rods, but the risk of complications is high. Cite this article: Bone Joint J 2018;100-B:772-9.

Escoliosis idiopáticas graves. ¿El abordaje y la instrumentación modifican los resultados? / Severe idiopathic scoliosis. Does the approach and the instruments used modify the results?

Objetivo: El objetivo de este trabajo es evaluar y comparar los resultados radiográficos y las complicaciones del tratamiento quirúrgico de escoliosis idiopáticas del adolescente mayores de 75◦ mediante doble abordaje (DA) o vía posterior aislada con instrumentación híbrida (PH) o «todo-tornillos» (PT). Material y método: Se realiza una revisión retrospectiva de 69 pacientes con escoliosis idiopática del adolescente mayor de 75◦ y seguimiento superior a los 2 años para analizar la flexibilidad de las curvas, la corrección obtenida y las complicaciones en función del tipo de cirugía. El análisis estadístico se realizó mediante el test de Kruskal-Wallis para variables no paramétricas. Resultados: No existen diferencias estadísticamente significativas entre los 3 grupos en los valores del ángulo de Cobb preoperatorio (DA = 89◦, PH = 83◦, PT = 83◦), en el postoperatorio inmediato (DA = 34◦, PH = 33◦, PT = 30◦) ni al final del seguimiento (DA = 36◦, PH = 36◦, PT = 33◦) (p > 0,05). El porcentaje de corrección (DA = 60%, PH = 57%, PT = 60%) fue similar entre grupos (p > 0,05). El porcentaje de complicaciones relacionadas con el procedimiento fue del 20,8% en DA, del 10% en PH y del 20% en PT. Dos pacientes en el grupo PT experimentaron cambios en la monitorización medular sin lesión neurológica y un paciente del mismo grupo experimentó una lesión incompleta diferida y temporal. Discusión y conclusiones: No se aprecian diferencias significativas en la corrección de las escoliosis idiopáticas graves entre los pacientes intervenidos mediante doble abordaje o por vía posterior aislada, independientemente del tipo de instrumentación utilizada (AU)

Objective: The aim of this work is to evaluate and compare the radiographic results and complications of the surgical treatment of adolescents with idiopathic scoliosis greater than 75 degrees, using a double approach (DA) or an isolated posterior approach with hybrid instruments (posterior hybrid [PH]), or with «all-pedicle screws» (posterior screws [PS]). Material and method: A retrospective review was performed on 69 patients with idiopathic scoliosis greater than 75◦, with a follow-up of more than 2 years, to analyze the flexibility of the curves, the correction obtained, and the complications depending on the type of surgery. The Kruskal-Wallis test for non-parametric variables was used for the statistical analysis. Results: There were no statistically significant differences between the 3 patient groups in the pre-surgical Cobb angle values (DA = 89◦, PH = 83◦, PS = 83◦), in the immediate post-surgical (DA = 34◦, PH = 33◦, PS = 30◦), nor at the end of follow-up (DA = 36◦, PH = 36◦, PS = 33◦) (P > .05). The percentage correction (DA = 60%, PH = 57%, PS = 60%) was similar between groups (P > .05). The percentage of complications associated with the procedure was 20.8% in DA, 10% in PH and 20% in PS. Two patients in the PS group showed changes, with no neurological lesions, in the spinal cord monitoring, and one patient in the same group suffered a delayed and transient incomplete lesion. Discussion and conclusions: No significant differences were observed in the correction of severe idiopathic scoliosis between patients operated using the double or isolated posterior approach, regardless of the type of instrumentation used (AU)

[Severe idiopathic scoliosis. Does the approach and the instruments used modify the results?]. / Escoliosis idiopáticas graves. ¿El abordaje y la instrumentación modifican los resultados?

OBJECTIVE: The aim of this work is to evaluate and compare the radiographic results and complications of the surgical treatment of adolescents with idiopathic scoliosis greater than 75 degrees, using a double approach (DA) or an isolated posterior approach with hybrid instruments (posterior hybrid [PH]), or with «all-pedicle screws¼ (posterior screws [PS]). MATERIAL AND METHOD: A retrospective review was performed on 69 patients with idiopathic scoliosis greater than 75°, with a follow-up of more than 2 years, to analyze the flexibility of the curves, the correction obtained, and the complications depending on the type of surgery. The Kruskal-Wallis test for non-parametric variables was used for the statistical analysis. RESULTS: There were no statistically significant differences between the 3 patient groups in the pre-surgical Cobb angle values (DA=89°, PH=83°, PS=83°), in the immediate post-surgical (DA=34°, PH=33°, PS=30°), nor at the end of follow-up (DA=36°, PH=36°, PS=33°) (P>.05). The percentage correction (DA=60%, PH=57%, PS=60%) was similar between groups (P>.05). The percentage of complications associated with the procedure was 20.8% in DA, 10% in PH and 20% in PS. Two patients in the PS group showed changes, with no neurological lesions, in the spinal cord monitoring, and one patient in the same group suffered a delayed and transient incomplete lesion. DISCUSSION AND CONCLUSIONS: No significant differences were observed in the correction of severe idiopathic scoliosis between patients operated using the double or isolated posterior approach, regardless of the type of instrumentation used.

Modulación del crecimiento de columnas escolióticas en animales de experimentación mediante el uso de barras de metal inteligente / Modulation of scoliotic spine growth in experimental animals using intelligent metal bars

Objetivo. Creación de un modelo experimental de escoliosis estructurada en ratas para evaluar la eficacia de los metales con memoria de forma para corregir gradualmente la deformidad a lo largo del tiempo. Material y método. Se generó una escoliosis experimental en ratas de 3 semanas mediante una sutura entre escápula y pelvis izquierdas durante 8 semanas, tras lo cual fueron aleatorizadas en 2 grupos: control, en los que se cortó la sutura, y nitinol, en los que además se implantó un alambre recto con memoria de forma anclado a la columna. Se realizaron radiografías seriadas para determinar la eficacia del nitinol en la corrección de la escoliosis. En un segundo tiempo, evaluamos los cambios histológicos a nivel del cuerpo vertebral apical y discos adyacentes pre y poscorrección. Resultados. Se indujo una cifoescoliosis progresiva media de 81,5°. En el grupo control, tras cortar la sutura, se produjo una reducción inicial de la deformidad pero luego permaneció estable a lo largo del tiempo (54° a las 2 semanas). En el grupo nitinol se observó una reducción progresiva del valor angular de la escoliosis, hasta 8,7° de media a las 2 semanas. El acuñamiento del cuerpo vertebral apical y de los discos adyacentes se corregía parcialmente tras 2 semanas de corrección de la deformidad. Conclusión. En este modelo de escoliosis, un alambre recto de nitinol anclado a la columna ha demostrado eficacia para la corrección gradual de la cifoescoliosis, y de los cambios estructurales asociados a la misma (AU)

Objective: To create an experimental structural scoliosis model in mice to evaluate the efficacy of shape-memory metals to gradually correct the deformity over time. Material and method: Experimental scoliosis was generated in 3 week-old mice by means of a suture between the left scapula and pelvis for 8 weeks. They were then randomised into two groups: a control group, in which the suture was cut, and another, in those that also had a Nitinol straight memory-wire implant fixed to the column. Serial X-rays were performed to determine the efficacy of the Nitinol in the correction of the scoliosis. In a second time, the histological changes at apical vertical body level and the adjacent discs were evaluated preand post-correction. Results: A mean 81.5◦ kyphoscoliosis was gradually induced. In the control group, after cutting the suture, an initial reduction in the deformity was observed, but later it remained stable throughout the time (54◦ at two weeks). In the Nitinol group, a gradual reduction was observed in the scoliosis angle value, to a mean of 8.7◦ at two weeks. The curvature of the apical vertebral body and adjacent discs were partially corrected after two weeks of correcting the deformity. Conclusion: This scoliosis model has demonstrated the efficacy of a straight Nitinol wire fixed to the spinal column in the gradual correction of kyphoscoliosis and in the changes in its adjacent structures (AU)

[Modulation of scoliotic spine growth in experimental animals using intelligent metal bars]. / Modulación del crecimiento de columnas escolióticas en animales de experimentación mediante el uso de barras de metal inteligente.

OBJECTIVE: To create an experimental structural scoliosis model in mice to evaluate the efficacy of shape-memory metals to gradually correct the deformity over time. MATERIAL AND METHOD: Experimental scoliosis was generated in 3 week-old mice by means of a suture between the left scapula and pelvis for 8 weeks. They were then randomised into two groups: a control group, in which the suture was cut, and another, in those that also had a Nitinol straight memory-wire implant fixed to the column. Serial X-rays were performed to determine the efficacy of the Nitinol in the correction of the scoliosis. In a second time, the histological changes at apical vertical body level and the adjacent discs were evaluated pre- and post-correction. RESULTS: A mean 81.5° kyphoscoliosis was gradually induced. In the control group, after cutting the suture, an initial reduction in the deformity was observed, but later it remained stable throughout the time (54° at two weeks). In the Nitinol group, a gradual reduction was observed in the scoliosis angle value, to a mean of 8.7° at two weeks. The curvature of the apical vertebral body and adjacent discs were partially corrected after two weeks of correcting the deformity. CONCLUSION: This scoliosis model has demonstrated the efficacy of a straight Nitinol wire fixed to the spinal column in the gradual correction of kyphoscoliosis and in the changes in its adjacent structures.

[Growing rods in early-onset scoliosis. Do they really help to control the deformity and spinal and thoracic growth?]. / Barras de crecimiento en escoliosis de inicio precoz ¿Permiten realmente el control de la deformidad y el crecimiento vertebral y torácico?

OBJECTIVE: To determine the efficacy of growing rods in the treatment of early onset scoliosis. MATERIAL AND METHODS: A total of 32 patients were treated using fusion techniques that included double growing rods and Vertical Expandable Prosthetic Titanium Ribs (VEPTR), in our Early Onset Scoliosis Centre between 2004 and 2011. After analysing the clinical histories and x-rays, 20 patients were included due to meeting the inclusion criteria. All patients had previously received conservative treatment with cranial traction and a series of plasters/corsets. The deformity was analysed before and after the initial surgery, and in successive tightenings, using the x-rays of the coronal and sagittal planes by means of the Cobb angle, as well as the longitudinal and coronal growth of the thorax, and the growth of the spinal column. A series of 188 x-rays of 53 patients with cystic fibrosis were studied in order to perform a comparative analysis with the patients with early-onset scoliosis. RESULTS: There was significant improvement in the angle (Cobb and kyphosis) and linear parameters (T1-S1 distance, T1-T12 distance, and coronal width of the thorax) after the initial surgery, but the successive tightenings had a minimal beneficial effect, losing effectiveness over a period of time. The patients with early-onset scoliosis showed a lower growth of the thorax compared to the patients with cystic fibrosis. DISCUSSION: Treatment of early-onset scoliosis with expandable devices is mainly beneficial with the initial procedure and the first tightenings, but shows a loss of efficacy over a period time.

Barras de crecimiento en escoliosis de inicio precoz ¿Permiten realmente el control de la deformidad y el crecimiento vertebral y torácico? / Growing rods in early-onset scoliosis. Do they really help to control the deformity and spinal and thoracic growth?

Objetivo. Determinar la eficacia de las barras de crecimiento en el tratamiento de la escoliosis de inicio precoz. Material y métodos. Entre 2004 y 2011, un total de 32 pacientes fueron intervenidos en nuestro centro de escoliosis de inicio precoz mediante técnicas sin fusión (barras de crecimiento dobles y VEPTR). De ellos, analizamos prospectivamente la historia clínica y las radiografías de 20 pacientes que cumplen los criterios de inclusión. Todos los pacientes habían recibido previamente tratamiento conservador con tracción craneal y yesos/corsés seriados. En cada radiografía (preoperatoria y postoperatoria de la cirugía inicial y de los sucesivos retensados) analizamos la deformidad en los planos coronal y sagital mediante el ángulo de Cobb, el crecimiento longitudinal y coronal del tórax, y el crecimiento de la columna vertebral. Se estudian 188 radiografías de tórax seriadas de 53 pacientes con fibrosis quística para hacer un análisis comparativo con los pacientes con escoliosis de inicio precoz. Resultados. La mejora de los parámetros angulares (Cobb y cifosis) y lineales (distancia T1-S1, distancia T1-T12 y anchura coronal del tórax) fue significativa con la cirugía inicial, pero los sucesivos retensados tuvieron un mínimo efecto beneficioso, perdiendo eficacia a lo largo del tiempo. Comparativamente con los pacientes con fibrosis quística, el crecimiento del tórax es menor en los pacientes con escoliosis de inicio precoz. Discusión. El tratamiento de la escoliosis de inicio precoz con sistemas expansibles resulta beneficioso fundamentalmente en el procedimiento inicial y primeros retensados, demostrando una pérdida de eficacia a lo largo del tiempo (AU)

Objective. To determine the efficacy of growing rods in the treatment of early onset scoliosis. Material and methods. A total of 32 patients were treated using fusion techniques that included double growing rods and Vertical Expandable Prosthetic Titanium Ribs (VEPTR), in our Early Onset Scoliosis Centre between 2004 and 2011. After analysing the clinical histories and x-rays, 20 patients were included due to meeting the inclusion criteria. All patients had previously received conservative treatment with cranial traction and a series of plasters/corsets. The deformity was analysed before and after the initial surgery, and in successive tightenings, using the x-rays of the coronal and sagittal planes by means of the Cobb angle, as well as the longitudinal and coronal growth of the thorax, and the growth of the spinal column. A series of 188 x-rays of 53 patients with cystic fibrosis were studied in order to perform a comparative analysis with the patients with early-onset scoliosis. Results. There was significant improvement in the angle (Cobb and kyphosis) and linear parameters (T1-S1 distance, T1-T12 distance, and coronal width of the thorax) after the initial surgery, but the successive tightenings had a minimal beneficial effect, losing effectiveness over a period of time. The patients with early-onset scoliosis showed a lower growth of the thorax compared to the patients with cystic fibrosis. Discussion. Treatment of early-onset scoliosis with expandable devices is mainly beneficial with the initial procedure and the first tightenings, but shows a loss of efficacy over a period time (AU)