Pedro Domenech

Anthropometry and body composition profile of girls with nonsurgically treated adolescent idiopathic scoliosis.

Study Design. Cross-sectional study with level III of evidence. Objective. To describe different anthropometric and body composition parameters of adolescent girls with adolescent idiopathic scoliosis (AIS), comparing them with the standards of a healthy age-matched population. Summary of Background Data. Body growth and development of adolescent girls with AIS seems to differ from the healthy subjects, especially at perpubertal stages. Young scoliotic adults have been found to be taller, lighter, and thinner than age-matched healthy population. Body composition profile taken from measurements of skin-fold thickness, bony diameters at different levels, and arm and legs perimeters has not been previously reported in AIS patients. Methods. A nonconsecutive series of 52 AIS girls (mean age: 13.9 years) with an average scoliotic curve of 27° Cobb (range: 20–58) underwent an anthropometric study. None of the AIS girls had been treated previously with spinal surgery. The control group consisted of 92 girls without spine deformity, matched in age (mean: 13.8 years). Weight, height, and skin-fold thickness in millimeters at six levels were measured. Body mass index (BMI), Ponderal index, percentage of body fat, percentage of muscular tissue, fat mass, lean body mass, muscular weight, bony weight, and residual weight were calculated using standard rules to estimate body composition. The somatotype components (endomorphy, mesomorphy, and ectomorphy) were calculated according to the Carter equations. Results. Compared with the control population, scoliotic girls had a significantly lower mean weight (51.4 ± 10.2 kg vs. 54.7 ± 8.1 kg; P < 0,05), a lower BMI (20.1 ± 3.4 vs. 21.4 ± 2.4; P < 0.001), and a higher Ponderal index (43.2 ± 2.4 vs. 42.2 ± 1.6; P < 0.01). Girls with AIS showed a progressive decrease of the BMI as the age increased. The percentage of body fat was also lower in scoliotic girls, without significant statistical differences (14.1 ± 3.8 vs. 15 ± 3.6). Out of the 52 AIS girls, 11 (21.2%) showed a BMI below 17.5, which has been considered the limit for anorexia. In the control group, only 3 of 92 girls (3.3%) had BMI below that level. The somatotype differed also between scoliotics and controls: higher in the ectomorphic component (3.29 ± 1.68 vs. 2.40 ± 1.11; P < 0.001), and lower in the mesomorphic component (2.86 ± 0.82 vs. 3.70 ± 1.11; P < 0.01) in AIS patients. Conclusion. The differences in some anthropometric parameters (weight, IMC, IP) and in the somatotype suggest that the idiopathic scoliosis not only disturbs normal spine growth but also seems to have implications on the whole corporal development. Whether these changes could be related to abnormal spinal growth or subsequent to nutritional changes in AIS still remains uncertain. Presumably, some endocrine factors affecting body composition and growth might be involved in the etiology of idiopathic scoliosis.

Using triggered electromyographic threshold in the intercostal muscles to evaluate the accuracy of upper thoracic pedicle screw placement (T3-T6).

Study Design. A prospective clinical study of high thoracic pedicle screws monitored with triggered electromyographic (EMG) testing. Objective. To evaluate the sensitivity of recording intercostal muscle potentials to assess upper thoracic screw placement. Summary of Background Data. Triggered EMG testing from rectus muscle recordings, which are innervated from T6 to T12, has identified medially placed thoracic pedicle screws. No clinical study has correlated an identical technique with the intercostal muscle for upper pedicle screws placed in the upper thoracic spine (T3–T6). Methods. A total of 311 high thoracic screws were placed in 50 consecutive patients. Screws were placed from T3 to T6 and were evaluated using an ascending method of stimulation until a compound muscle action potential was obtained from the intercostal muscles. Screw position was then evaluated using computed tomography and results were compared with evoked EMG threshold values. Results. Fifteen screws (5%) showed penetration on postoperative computed tomography scans. Eleven screws showed medial cortical breakthrough (3.6%), 6 had stimulation thresholds ≤6 mA, and 5 had stimulation thresholds between 6 and 10 mA. Stimulation values for all breached screws decreases 60% to 65% from their mean. Four screws (1.3%) showed lateral cortical breakthrough with stimulation thresholds >20 mA. Of the 296 screws with thresholds between 6 and 20 mA, 285 (91%) were within the vertebra. No postoperative neurologic complications were noted in any of the 50 patients. Conclusion. In this series, cortical violation is highly unlikely in patients whose stimulation threshold lies between 6 and 20 mA with values 60% to 65% decreased from the mean (98% negative predictive value). Although verification of screw placement should not depend solely on stimulation thresholds, pedicle screw stimulation provides rapid and useful intraoperative information on screw placement during procedures involving the use of thoracic pedicle screws.

Long-term result of major spinopelvic arthrodeses in scoliosis: importance of age, walking ability and type of iliac fixation

OBJECTIVE: To determine the factors that influence lumbosacral instrumentation failures following spino-pelvic fusions. METHODS: A retrospective study of patients diagnosed with scoliosis who underwent spinopelvic fusion via posterior, from T2 or T3 proximally to iliac crest, using pedicle and iliac screws. Instrumentation failures were analyzed, and the association of this complication with different parameters was studied. RESULTS: We present 44 patients, with an average age of 24 years, with different etiologies. The mean value of the largest preoperative major curve was 74.2°, and in the final review, it was 67%. The anterior-posterior imbalance, pelvic tilt, thoracic kyphosis, lumbar lordosis and lateral imbalance were significantly improved in the final review. There were instrumentation failures in 41% cases, all at the lumbosacral level. A significant association was found between increased instrumentation failures in patients over 17 years and in patients with independent walking ability. In 24 patients, a bilateral single iliac screw was used and in 20 patients, two or more screws were used. Both groups had a similar incidence of failures. In the group with two or more screws, only rod breakages occurred, without detachment or screw lysis. There was lower instrumentation failure incidence in the patients who underwent L3-S1 interbody fusion or a third rod attached with sublaminar compression hooks. CONCLUSIONS: This series had 41% instrumentation failures, all located at lumbosacral level. There were significant more instrumentation failures in patients with independent walking ability and those aged over 17 years. There was lower instrumentation failure incidence in the patients who underwent L3-S1 interbody fusion or a third rod attached with sublaminar compression hooks.

Resultado a largo plazo de las fusiones largas espinopelvicas en escoliosis: importancia de la edad, la capacidad de marcha y el tipo de fijación ilíaca

OBJECTIVE: To determine the factors that influence lumbosacral instrumentation failures following spino-pelvic fusions. METHODS: A retrospective study of patients diagnosed with scoliosis who underwent spinopelvic fusion via posterior, from T2 or T3 proximally to iliac crest, using pedicle and iliac screws. Instrumentation failures were analyzed, and the association of this complication with different parameters was studied. RESULTS: We present 44 patients, with an average age of 24 years, with different etiologies. The mean value of the largest preoperative major curve was 74.2°, and in the final review, it was 67%. The anterior-posterior imbalance, pelvic tilt, thoracic kyphosis, lumbar lordosis and lateral imbalance were significantly improved in the final review. There were instrumentation failures in 41% cases, all at the lumbosacral level. A significant association was found between increased instrumentation failures in patients over 17 years and in patients with independent walking ability. In 24 patients, a bilateral single iliac screw was used and in 20 patients, two or more screws were used. Both groups had a similar incidence of failures. In the group with two or more screws, only rod breakages occurred, without detachment or screw lysis. There was lower instrumentation failure incidence in the patients who underwent L3-S1 interbody fusion or a third rod attached with sublaminar compression hooks. CONCLUSIONS: This series had 41% instrumentation failures, all located at lumbosacral level. There were significant more instrumentation failures in patients with independent walking ability and those aged over 17 years. There was lower instrumentation failure incidence in the patients who underwent L3-S1 interbody fusion or a third rod attached with sublaminar compression hooks.

Resultado a longo prazo das grandes artrodeses espinopélvicas em escoliose: importância da idade, da capacidade de marcha e do tipo de fixação ilíaca

OBJECTIVE: To determine the factors that influence lumbosacral instrumentation failures following spino-pelvic fusions. METHODS: A retrospective study of patients diagnosed with scoliosis who underwent spinopelvic fusion via posterior, from T2 or T3 proximally to iliac crest, using pedicle and iliac screws. Instrumentation failures were analyzed, and the association of this complication with different parameters was studied. RESULTS: We present 44 patients, with an average age of 24 years, with different etiologies. The mean value of the largest preoperative major curve was 74.2°, and in the final review, it was 67%. The anterior-posterior imbalance, pelvic tilt, thoracic kyphosis, lumbar lordosis and lateral imbalance were significantly improved in the final review. There were instrumentation failures in 41% cases, all at the lumbosacral level. A significant association was found between increased instrumentation failures in patients over 17 years and in patients with independent walking ability. In 24 patients, a bilateral single iliac screw was used and in 20 patients, two or more screws were used. Both groups had a similar incidence of failures. In the group with two or more screws, only rod breakages occurred, without detachment or screw lysis. There was lower instrumentation failure incidence in the patients who underwent L3-S1 interbody fusion or a third rod attached with sublaminar compression hooks. CONCLUSIONS: This series had 41% instrumentation failures, all located at lumbosacral level. There were significant more instrumentation failures in patients with independent walking ability and those aged over 17 years. There was lower instrumentation failure incidence in the patients who underwent L3-S1 interbody fusion or a third rod attached with sublaminar compression hooks.

234 Alignement Coplanaire (AC) : une nouvelle technique de correction tridimensionnelle de la scoliose. Résultats préliminaires en courbes type 1 de Lenke

Objectifs Presenter les resultats preliminaires de une nouvelle technique de correction de la scoliose, basee sur le realignement coplanaire des axes vertebraux. Methodes Vint cinq patients presentant une scoliose idiopathique de l’adolescent (Lenke type 1) furent traites par chirurgie posterieure, utilisant vis pediculaires) et reduction par Alignement Coplanaire(alignement dans le meme plan des pedicules. Description de l’AC :apres insertion des vis pediculaires, sont mis en place des prolongateurs rainures du cote de la convexite de tous les niveaux de la courbure puis est introduite une barre au travers de la rainure aux extremites des prolongateurs, creant un axe de rotation. Une seconde barre est introduite a cote de la premiere. La separation progressive de ces deux barres le long de la rainure des prolongateurs les amenera progressivement dans un seul plan, faisant coplanaires les axes anteroposterieurs des vertebres, et corrigeant la rotation et la translation. La separation des extremites des prolongateurs corrige la divergence posterieure des axes dans la zone de cyphose. Les courbes furent mesurees sur des teleradiographies du rachis debout en pre et en postoperatoire. La rotation vertebrale fut mesuree directement par scanner et RMN et indirectement sur les radiographies. Resultats Les courbes dorsales se corrigerent de 61 a 16° (73 %), les dorsolombaires de 39 a 12° (70 %). La rotation vertebrale au sommet de la courbe dorsale se corrigeait de 24 a 10° (56 %). La cyphose dorsale moyenne preoperatoire etait de 18° et se maintint egale en postoperatoire, pourtant, aucun patient ne presentait a la fin un modificateur sagittal de Lenke (-). La gibbosite dorsale passa de 30 a 11 mm en postoperatoire (65 %), sans qu’il fut necessaire de pratiquer aucune thoracoplastie. Il n’y eut pas de complications perioperatoires notables. Conclusion Dans cette serie, avec la technique d’AC une bonne reduction tridimensionnelle de la scoliose a ete obtenue. Les forces correctrices se distribuent entre tous les segments de la courbe et s’appliquent avant la mise ne place des barres de fixation definitives, les protegeant des efforts des manœuvres de reduction et facilitant leur insertion. On n’a pas observe de complications liees a la technique. L’AC pourrait permettre d’obtenir une correction planifiee en preoperatoire.