Thoracolumbar burst fractures, short x long fixation: a meta-analysis / Fraturas toracolombares do tipo explosão, fixação curta x longa: uma metanálise / Fracturas toracolumbares tipo explosión, fijación corta x larga: un meta-análisis

ABSTRACT The number of fixed segments in the surgical treatment of thoracolumbar burst fractures remains controversial. This study aims to compare the results of short and long fixation in thoracolumbar burst fractures through a meta-analysis of studies published recently. MEDLINE and Cochrane databases were used. Randomized controlled trials and non-randomized comparative studies (prospective and retrospective) were selected. Data were analyzed with the software Review Manager. There was no statistically significant difference in the Cobb angle of preoperative kyphosis. Long fixation showed lower average measurements postoperatively (MD = 1.41; CI = 0.73-2.08; p<0.0001) and in the last follow-up (MD = 3.98; CI = 3.22-4.75; p<0.00001). The short fixation showed the highest failure rates (RD = 4.03; CI = 1.33-12.16; p=0.01) and increased loss of height of the vertebral body (MD = 1.24; CI = 0.49-1.98; p=0.001), with shorter operative time (MD = -24.54; CI = -30.16 - -18.91; p<0.00001). There was no significant difference in blood loss and clinical outcomes. The high rates of kyphosis correction loss with short fixation and the lower correction rate in the immediate postoperative period were validated. There was no significant difference in the blood loss rates because arthrodesis was performed in a short segment in the analyzed studies. The short fixation was performed in a shorter operative time, as expected. No study has shown superior clinical outcomes. The short fixation had worse rates of kyphosis correction in the immediate postoperative period, and increased loss of correction in long-term follow-up, making the long fixation an effective option in the management of this type of fracture.

RESUMO A quantidade de segmentos fixados no tratamento cirúrgico das fraturas toracolombares tipo explosão continua controverso. Este estudo tem como objetivo comparar os resultados da fixação curta e da longa nas fraturas toracolombares do tipo explosão, por meio de uma metanálise dos estudos publicados recentemente. Foram utilizadas as bases de dados MEDLINE e COCHRANE. Foram selecionados estudos controlados randomizados e estudos comparativos não randomizados (prospectivos e retrospectivos). Os dados foram analisados com o software Review Manager. Não houve diferença estatisticamente significante na medida do ângulo de Cobb da cifose pré-operatória. A fixação longa apresentou medidas médias inferiores no pós-operatório (MD = 1,41; IC = 0,73-2,08; p < 0,0001) e no último seguimento (MD = 3,98; IC =3,22-4,75; p < 0,00001). A fixação curta apresentou taxas de falha maiores (RD = 4,03; IC = 1,33-12,16; p = 0,01) e maior perda de altura do corpo vertebral (MD = 1,24; IC = 0,49-1,98; p = 0,001), com menor tempo operatório (MD = -24,54; IC = -30,16 - -18,91; p < 0,00001). Não houve diferença estatisticamente significante na perda sanguínea e nos desfechos clínicos. As taxas elevadas de perda da correção da cifose na fixação curta e a menor taxa de correção no pós-operatório imediato foram validadas. Não houve diferença estatisticamente significante quanto às taxas de perda sanguínea, porque a artrodese foi realizada em um segmento curto nos trabalhos analisados. A fixação curta teve menor tempo operatório, como esperado. Nenhum estudo demonstrou superioridade dos resultados clínicos. A fixação curta apresentou taxas piores de correção da cifose no pós-operatório imediato e maior perda da correção no seguimento a longo prazo, fazendo da fixação longa uma opção efetiva no manejo deste tipo de fratura.

RESUMEN El número de segmentos fijados en el tratamiento quirúrgico de las fracturas toracolumbares tipo explosión sigue siendo controvertido. Este estudio tiene como objetivo comparar los resultados de fijación corta y larga en las fracturas toracolumbares tipo explosión, a través de un meta-análisis de estudios publicados recientemente. Se utilizaron las bases de datos MEDLINE y COCHRANE. Se seleccionaron los ensayos controlados aleatorios y estudios comparativos no aleatorios (prospectivos y retrospectivos). Los datos fueron analizados con el software Review Manager. No hubo diferencia estadísticamente significativa en cuanto a la medida del ángulo de Cobb de la cifosis preoperatoria. Lar fijación larga mostró mediciones promedio más bajas en el postoperatorio (MD = 1,41, IC = 0,73-2,08; p < 0,0001) y en el último seguimiento (MD = 3,98, IC = 3,22-4,75; p < 0,00001). La fijación corta mostró las tasas de fracaso más altas (RD = 4,03, IC = 1,33-12,16; p = 0,01) y una pérdida mayor de la altura del cuerpo vertebral (MD = 1,24, IC = 0,49-1,98; p = 0,001), con un menor tiempo operatorio (MD = -24,54; IC = -30,16 - -18.91; p < 0,00001). No hubo diferencia significativa en la pérdida de sangre y los resultados clínicos. Se validaron las altas tasas de pérdida de corrección de la cifosis con la fijación corta y la menor tasa de corrección en el postoperatorio inmediato. No hubo diferencia significativa en las tasas de pérdida de sangre porque la artrodesis se realizó en un segmento corto en los estudios analizados. La fijación corta tuvo menor tiempo operatorio, como se esperaba. Ningún estudio ha demostrado resultados clínicos superiores. La fijación corta tuvo peores tasas de corrección de la cifosis en el postoperatorio inmediato y mayor pérdida de corrección en el seguimiento a largo plazo, por lo que la fijación larga es una opción efectiva en el manejo de este tipo de fracturas.

Determination of thigh volume in youth with anthropometry and DXA: agreement between estimates.

This study examined the agreement between estimates of thigh volume (TV) with anthropometry and dual-energy x-ray absorptiometry (DXA) in healthy school children. Participants (n=168, 83 boys and 85 girls) were school children 10.0-13.9 years of age. In addition to body mass, height and sitting height, anthropometric dimensions included those needed to estimate TV using the equation of Jones & Pearson. Total TV was also estimated with DXA. Agreement between protocols was examined using linear least products regression (Deming regressions). Stepwise regression of log-transformed variables identified variables that best predicted TV estimated by DXA. The regression models were then internally validated using the predicted residual sum of squares method. Correlation between estimates of TV was 0.846 (95%CI: 0.796-0.884, Sy·x=0.152 L). It was possible to obtain an anthropometry-based model to improve the prediction of TVs in youth. The total volume by DXA was best predicted by adding body mass and sum of skinfolds to volume estimated with the equation of Jones & Pearson (R=0.972; 95%CI: 0.962-0.979; R (2)=0.945).

Modeling developmental changes in functional capacities and soccer-specific skills in male players aged 11-17 years.

This study evaluates the contributions of age, growth, skeletal maturation, playing position and training to longitudinal changes in functional and skill performance in male youth soccer. Players were annually followed over 5 years (n = 83, 4.4 measurements per player). Composite scores for functional and skill domains were calculated to provide an overall estimate of performance. Players were also classified by maturity status and playing position at baseline. After testing for multicollinearity, two-level multilevel (longitudinal) regression models were obtained for functional and skill composite scores. The scores improved with age and training. Body mass was an additional predictor in both models [functional (late maturing): 13.48 + 1.05 × centered on chronological age (CA)-0.01 × centered CA(2)-0.19 × fat mass (FM) + 0.004 × annual volume training-1.04 × dribbling speed; skills (defenders): 7.62 + 0.62 × centered CA-0.06 × centered CA(2) + 0.04 × fat-free mass-0.03 x FM + 0.005 × annual volume training-0.19 × repeated-sprint ability + 0.02 × aerobic endurance]. Skeletal maturity status was a significant predictor of functional capacities and playing position of skill performance. Sound accuracy of each multilevel model was demonstrated on an independent cross-sectional sample (n = 52).

Sport selection in under-17 male roller hockey.

Characteristics of 32 international and 41 local under-17 (U-17) (14.5-16.5 years) roller hockey players were considered in the context of discrimination by competitive level using training history, anthropometry, skeletal maturation, and several laboratory and field performance tests. More international (42%) than local (22%) players were advanced in maturity status. International players had slightly less hockey experience (years), but had more practice sessions and match time (minutes) during the season. Local players were shorter and attained better performance in the 25-m dash, while international players performed better in sit-ups, ball throw and 20-m shuttle run. The fatigue index derived from the Wingate anaerobic test was higher among local players, while peak torques of knee extension and flexion were greater in international players. Stepwise discriminant function correctly classified 85% of players by competitive level based on grip strength, ratio of eccentric and concentric knee extension, number of training sessions, playing time and fatigue index. The results suggested an interaction among strength, anaerobic fitness and training plus game time as factors in discriminating international from local level players and by inference in the selection and development of youth roller hockey players.