Comparison of the use of supine bending and traction radiographs in the selection of the fusion area in adolescent idiopathic scoliosis

STUDY DESIGN: A study was done to evaluate the use of voluntary supine side bending radiographs and Risser table traction radiographs in adolescent patients undergoing posterior spinal fusion for idiopathic scoliosis. OBJECTIVES: To compare the usefulness of supine side bending and traction radiographs in assessing curve flexibility and determining fusion levels in patients undergoing posterior spinal fusion for adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Supine side bending radiographs have been used in the preoperative evaluation of idiopathic scoliosis to determine curve flexibility and fusion area. Traction films have been used to determine the flexibility of large curves and neuromuscular curves where active side bending is not possible. No study to date has compared the use of these films in patients with adolescent idiopathic scoliosis undergoing surgery. METHODS: Seventy-five patients with more than a 2-year follow-up period after surgery were included in this study. Preoperative radiographs included a standing posteroanterior and lateral film and both supine maximal voluntary side bending films and a traction film done on a Risser table. A preoperative review of these radiographs was done to determine curve flexibility and fusion levels. At follow-up evaluation, the patients were examined for any evidence of decompensation or "adding-on" of levels. RESULTS: For curves less than 60 degrees, side bending radiographs showed greater curve correction than traction radiographs, whereas the opposite was true for curves greater than 60 degrees. For King I and II curves, side bending radiographs were superior for determination of lumbar curve flexibility and for distinguishing these two types of curves. On traction radiographs, the stable vertebra was 1.4 vertebral levels higher than on the standing film. When the fusion level was moved proximally because of the traction radiograph, decompensation or "adding-on" commonly occurred. CONCLUSIONS: Supine bending radiographs are superior to traction radiographs for assessing curve flexibility except for curves more than 60 degrees. The selection of the distal extent of fusion based on the traction radiograph gave a large number of poor results. The selection of fusion levels in adolescent Idiopathic scoliosis is best determined by a combination of standing posteroanterior and lateral radiographs and the supine maximum voluntary bend films.     

New anterior instrumentation for the management of thoracolumbar and lumbar scoliosis. Application of the Kaneda two-rod system

STUDY DESIGN: The Kaneda multisegmental instrumentation is a new anterior two-rod system for the correction of thoracolumbar and lumbar spine deformities. This system consists of a vertebral plate and two vertebral screws for individual vertebral bodies and two semirigid rods to interconnect the vertebral screws. Clinical results of 25 thoracolumbar and lumbar scoliosis patients treated with this new instrumentation were analyzed. OBJECTIVES: To evaluate the efficacy of the new anterior instrumentation in correction and stabilization of thoracolumbar and lumbar scoliosis. SUMMARY OF BACKGROUND DATA: Since Dwyer first introduced the concept of anterior spinal instrumentation and fusion for scoliosis, anterior surgery has gradually gained acceptance. In 1976, a useful modification for the anterior spinal instrumentation, which reportedly provided means of lordosation and vertebral body derotation, was described. However, some authors reported a high tendency of the implant breakage, loss of correction, progression of the kyphosis, and pseudoarthrosis as the major complications. To overcome the disadvantages of Zielke instrumentation, the authors have developed a new anterior spinal instrumentation (two-rod system) for the management of thoracolumbar and lumbar scoliosis. METHODS: Anterior correction and fusion using Kaneda multisegmental instrumentation was performed in 25 patients with thoracolumbar or lumbar scoliosis. The average follow-up period was 3 years, 1 month (range, 2 years to 4 years, 7 months). There were 20 patients with idiopathic scoliosis (13 adolescents and seven adults) and five patients with other types of scoliosis, including congenital and other etiologies. All patients had correction of scoliosis by fusion within the major curve, and for 16 of the 25 patients, the most distal end vertebra was not included in the fusion (short fusion). Radiographic evaluations were performed to analyze frontal and sagittal alignments of the spine. RESULTS: The average correction rate of scoliosis was 83%. Over the instrumented levels, the correction rate was 90%. Preoperative kyphosis of the instrumented levels of 7 degrees was corrected to 9 degrees of lordosis. Sagittal lordosis of the lumbosacral area beneath the fused segments averaged 51 degrees before surgery and was reduced to 34 degrees after surgery. The trunk shift was improved from 25 mm before surgery to 4 mm at final follow-up evaluation. The average improvement in the lower end vertebra tilt-angle was 97% in those patients whose lower end vertebra was included in the fusion and 83% in patients whose lower end vertebra was not included in the fusion. Apical vertebral rotation showed an average correction rate of 86%. At final follow-up evaluation, all patients demonstrated solid fusion without implant-related complications. There was 1.5 degrees of frontal plane and 1.5 degrees of sagittal plane correction loss within the instrumented area at final follow-up evaluation. CONCLUSIONS: New anterior two-rod system showed excellent correction of the frontal curvature and sagittal alignment with extremely high correction capability of rotational deformities. Furthermore, correction of thoracolumbar kyphosis to physiologic lordosis was achieved. This system provides flexibility of the implant for smooth application to the deformed spine and overall rigidity to correct the deformity and maintain the fixation without a significant loss of correction or implant failure compared with conventional one-rod instrumentation systems in anterior scoliosis correction.     

Changes in the unfused lumbar spine in patients with idiopathic scoliosis. A 5- to 9-year assessment after cotrel-dubousset instrumentation

STUDY DESIGN: Postoperative changes in the lumbar spine were studied retrospectively in patients with adolescent idiopathic scoliosis who had been treated with Cotrel-Dubousset instrumentation. OBJECTIVE: To examine middle-term changes in the unfused lumbar segments below an instrumented scoliosis fusion. SUMMARY OF BACKGROUND DATA: Scoliosis fusion by the Harrington method is known to be associated with a flat back in the fused area and subsequent degenerative changes in the segments below the fusion. No data have yet been published concerning a segmental instrumentation system. PATIENTS AND METHODS: Thirty patients with idiopathic scoliosis, between the ages of 14 and 22 years at the time of surgery, were observed for 5-9 years after surgery. Activity, pain, complications, and 21 radiographic parameters were assessed. RESULTS: The prevalence of low back pain increased from 3% before surgery to 20% at the final follow-up visit, although in none of the patients was the pain so severe that specific treatment was required. Radiographically, uninstrumented lumbar segments generally were realigned successfully in the frontal plane. Analyses in the sagittal plane revealed tendencies to a gradual increase in lumbar lordosis, anterior-upward tilting of the lowest instrumented vertebra, and posterior shift of the sagittal spinal balance. During the follow-up period, seven patients (23%) developed degenerative changes, including mild junctional kyphosis, retrolisthesis, narrowing of disc spaces, or osteophytes. CONCLUSION: Whereas the overall clinical and radiographic results of surgery were satisfactory, the unfused lumbar segments required careful surveillance, especially in the sagittal plane.     

Relation between adolescent idiopathic scoliosis and morphologic somatotypes

STUDY DESIGN: A prospective and controlled comparative study. OBJECTIVES: To verify the difference in morphologic appearance between a group of adolescents with progressive adolescent idiopathic scoliosis and a control group of normal adolescents. SUMMARY OF BACKGROUND DATA: In a previous retrospective study, the possibility of a relation between progressive adolescent idiopathic scoliosis and specific morphotypes was demonstrated. METHODS: Fifty-two adolescent girls with progressive adolescent idiopathic scoliosis were compared with an age-matched control group of 62 unaffected girls using a classification technique based on morphologic somatotypes. Morphotypes were evaluated with standardized pre-established criteria based on Sheldon's technique. RESULTS: Patients with progressive adolescent idiopathic scoliosis showed significantly less mesomorphism (mean value of 0.88 +/- 0.51) than control girls (mean value of 1.72 +/- 0.52). CONCLUSION: Adolescent girls with progressive adolescent idiopathic scoliosis have a morphologic somatotype that is different from the normal adolescent population. Subjects with progressive adolescent idiopathic scoliosis are significantly less mesomorphic than control girls. This observation may be of value as a predictive factor for early identification of subjects with adolescent idiopathic scoliosis at greater risk of progression.     

The lordotic effect of the OSI frame on operative adolescent idiopathic scoliosis patients

STUDY DESIGN: A prospective evaluation of adolescent idiopathic scoliosis patients undergoing operative treatment on the Orthopedic Systems Incorporated (OSI; Jackson) frame. OBJECTIVES: To investigate prospectively thoracic, thoracolumbar, and lumbar sagittal alignments in patients with adolescent idiopathic scoliosis who undergo an instrumented posterior spinal fusion on the OSI frame. SUMMARY OF BACKGROUND DATA: In several studies, it has been shown that patient positioning on various operative frames is an important component of ultimate lumbar sagittal alignment. However, these studies have all concentrated on the lumbar spine, and no sagittal plane alignment data in adolescent idiopathic scoliosis patients have been reported in the thoracic and thoracolumbar junction as it relates to intraoperative positioning, correction maneuvers and correlative postoperative results. METHODS: Thirty-nine patients with operative adolescent idiopathic scoliosis treated with an instrumented posterior spinal fusion on the OSI frame were prospectively evaluated. Standing preoperative, intraoperative, and postoperative long-cassette lateral radiographs were reviewed with regional and segmental Cobb measurements of the thoracic, thoracolumbar junction, and lumbar spine obtained. RESULTS: Thoracic kyphosis (T1-T12) measured +34 degrees before surgery, +28 degrees during surgery, and +30 degrees after surgery, Thus, a statistically significant decrease was noted in thoracic kyphosis secondary to prone positioning on the OSI frame ( P < 0.05). Thoracolumbar spine measurements from T10 to L2 also showed a lordotic trend from +2 degrees before surgery, to -4 degrees during surgery, to -8 degrees after surgery, which was also statistically significant (P < 0.05). Total lumbar lordosis from T12 to S1 remained relatively unchanged from -60 degrees before surgery, to -59 degrees during surgery, to -60 degrees after surgery. However, segmental lumbar lordosis measured from T12 to the lowest instrumented vertebra showed a statistically significant increase in lordosis from -17 degrees before surgery, to -19 degrees during surgery, to -23 degrees after surgery (P < 0.05). Those patients in whom lumbar pedicle screws were used (vs. hooks alone) had the greatest increase in lumbar instrumented lordosis. CONCLUSIONS: Performing adolescent idiopathic scoliosis correction on the OSI frame tends to decrease thoracic kyphosis, increase thoracolumbar lordosis, and increase segmental instrumented lumbar lordosis, while it maintains total lumbar lordosis.     

Morphologic discrimination among healthy subjects and patients with progressive and nonprogressive adolescent idiopathic scoliosis

STUDY DESIGN: A prospective and controlled comparative study. OBJECTIVES: To identify variables that would allow discrimination among patients with progressive adolescent idiopathic scoliosis, patients with nonprogressive adolescent idiopathic scoliosis, and control subjects. SUMMARY OF BACKGROUND DATA: In a previous study, the correlation was demonstrated between morphologic somatotypes and adolescent idiopathic scoliosis. METHODS: One hundred forty-six subjects were evaluated anthropometrically and were classified according to their morphologic somatotype. Of these subjects, 52 were adolescent girls with progressive idiopathic scoliosis, whereas 32 girls had nonprogressive idiopathic scoliosis. The control group was composed of 62 healthy adolescent girls. Somatotype values for ectomorphism, mesomorphism, and endomorphism were obtained according to a technique based on Sheldon's method, and 77 anthropometric measurements of segments of the thorax, head, and limbs were taken. RESULTS: The discriminant analysis realized on a subset of 18 variables allowed the correct identification of each subject's group in 84% of the cases. CONCLUSIONS: It is possible to differentiate healthy adolescent subjects, patients with nonprogressive adolescent idiopathic scoliosis, and patients with progressive idiopathic scoliosis by using anthropometric measurements and morphologic classification. These findings may be useful in the early detection of children at risk for progression of scoliosis and may allow earlier application of treatment methods without waiting for a significant increase in the curve.     

Review of 87 cases of scoliosis surgically treated

BACKGROUND: The authors compared the results and complications in surgical treatment of idiopathic scoliosis with Harrington's rod instrumentation with subtrasversal wires in dorsal treat. METHODS: A research on 87 cases operated on for idiopathic scoliosis from 1987 to 1995 is carried out. The 87 cases include 65 females and 25 males, 16 years old in average (range, 11 to 30). The curvature in Cobb's degrees and rotation of vertebrae with Raimondi's method on radiographs take just before, 15 days later and an year later on operation was measured. The patients have been divided into two groups: the first of 77 patients operated with Harrington's rod instrumentation; the second of 10 patients operated with Harrington's rod instrumentation and subtrasversal wires. RESULTS: In a general analysis without taking in to consideration the type and the seriousness of curvature it was obtained a better correction and derotation of vertebrae in patients of second group. The same group with wires had obtained a better correction and derotation of vertebrae in dorsal scoliosis from 40 degrees to 60 degrees and in the double scoliosis, while the first group obtained better results in dorsal scoliosis from 60 degrees to 80 degrees and in derotation of vertebrae on dorsal treat of double scoliosis. One case of pseudarthrosis in every group was observed. Any neurological complication were observed. CONCLUSIONS: The conclusions is drawn that the application of subtrasversal wire improves the Harrington's technique for the correction and derotation of dorsal and double scoliosis without neurological complications sometimes present with subliminar wires.     

P450RAI (CYP26A1) maps to human chromosome 10q23-q24 and mouse chromosome 19C2-3

STUDY DESIGN: A case report. OBJECTIVES: To document a fracture of the 11th thoracic vertebra after spine fusion for adult idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Three cases of vertebral fractures associated with spine fusion for scoliosis were found in the literature. METHODS: Medical and radiologic records and related literature were reviewed. RESULTS: A 30-year-old woman had undergone anterior and posterior fusion with Cotrel-Dubousset instrumentation for progressive idiopathic scoliosis. Two years after surgery, she was in a car accident. A radiographic study and computer tomographic scanning depicted a fracture of T11 and bending of the rods. Observation was instituted and symptoms resolved. CONCLUSIONS: Fracture of a vertebra within an extensive spine fusion for scoliosis is rare. The 360 degrees solid fusion together with strong posterior instrumentation may have had some protective effect in this patient.     

Nighttime bracing for adolescent idiopathic scoliosis with the Charleston Bending Brace: long-term follow-up

We report long-term experience with the Charleston Bending Brace for treatment of adolescent idiopathic scoliosis. This brace holds the patient in maximal side-bending correction and is worn at nighttime only. Patients included in this prospective multicenter study met all of the following criteria: skeletal immaturity (Risser 0, 1, or 2), curvature >25 degrees before bracing, no prior treatment, and >1-year follow-up since completion of bracing (skeletal maturity or progression to surgery). All curves were monitored and reported. There were 149 structural curves in 98 patients. Sixty-five (66%) patients showed improvement or <5 degrees change in curvature. Seventeen (17%) patients progressed to the point of requiring surgery for their scoliosis. Based on these long-term results and improvement of the natural history of adolescent idiopathic scoliosis, continued use of the Charleston Bending Brace is justified.     

A retrospective analysis of continuous cervical epidural block

General principles of construction of TSRH instrumentation and its use for treatment of idiopathic King type III scoliosis have been presented. Surgical technique has been described on the basis of procedure performed in the case of 13 years old girl with primary right sided thoracic adolescent scoliosis.     

Hemifacial hypoplasia and hypomelanosis of Ito

Seventy patients with adolescent idiopathic right thoracic scoliosis had full assessment of their pulmonary function using a computerised pulmonary function system. Their mean age at evaluation was 13.8 years. The following measurements were obtained from anteroposterior and lateral standing and antero-posterior supine bending radiographs: lateral curvature, vertebral rotation, kyphosis, maximum sterno-vertebral distance and apical rib-vertebral angles. Using the above measurements, the flexibility of curve, vertebral rotation and rib-vertebral angle asymmetry were calculated. Patients were classified into three groups on the basis of their predicted vital capacity, to determine whether radiological features of deformity can help identify patients with compromised pulmonary function. The mean Cobb angle and vertebral rotation for the 70 patients were 50 degrees (range 35-100 degrees) and 22 degrees (range 1-44 degrees) respectively. The mean flexibility of curve and vertebral rotation were 52% and 49% respectively. Mean thoracic kyphosis was 25 degrees, ranging from -7 to 55 degrees. Of the patients with Cobb angle less than 90 degrees, 71% had vital capacity less than 80% of predicted values, and of these, 18% had marked compromise of vital capacity (less than 60% of predicted values). Mean values of Cobb angle, vertebral rotational flexibility, kyphosis, rib-vertebral angle asymmetry (in standing as well as supine bending radiographs) differed significantly between patients with more than 80% of predicted vital capacity and those with 60% or less of predicted values. Radiological features indicative of better pulmonary function were: rotational flexibility exceeding 55%, rib-vertebral angle asymmetry (standing) less than 25 degrees and kyphosis greater than 15 degrees. Two deformity parameters--that give a better prediction of pulmonary function than the widely used Cobb angle, vertebral rotational flexibility and rib-vertebral angle asymmetry--were identified in this study.     

Cotrel-Dubousset instrumentation. Results in 52 patients

Fifty-two posterior spinal fusions were performed for pediatric idiopathic, congenital, and neuromuscular scoliotic curves. Cotrel-Dubousset instrumentation was used in all patients. Nine had prior anterior spinal releases and fusions. The patterns were mixed, with a predominance of right thoracic curvatures. The average preoperative curve measured 60.6 degrees, with correction to 29. Seven patients required revision surgery, and 17 wore orthoses after operation. There were 17 complications in this group, including hook pullout, prominent hardware, infection, pseudarthrosis, and two cases of broken Cotrel-Dubousset instrumentation rods. Fatigue failure of this instrumentation, secondary to pseudarthrosis, has not been reported previously, and these two cases are presented in detail. The operative morbidity and difficulty were increased in the larger idiopathic curves and in neuromuscular and congenital scoliosis. Cotrel-Dubousset instrumentation is an overall excellent tool for the multiplanar correction of scoliosis and is amenable to revision surgery.     

A comparative study of TLSO, Charleston, and Milwaukee braces for idiopathic scoliosis

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To determine which of TLSO, Charleston, or Milwaukee bracing best prevents curve progression and surgery in adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Bracing has been shown to prevent curve progression in idiopathic scoliosis, when compared with no treatment. However, there is little literature available comparing the effectiveness of different brace designs. METHODS: One hundred seventy patients who completed brace treatment for adolescent idiopathic scoliosis between 1988 and 1995 were studied. Forty-five thoracolumbosacral orthoses, 95 Charleston braces, and 35 Milwaukee braces were used. Thoracolumbosacral orthoses and Charleston braces were used on comparable curves, whereas Milwaukee braces were used in a subgroup in which the other brace designs were considered inappropriate. Evaluated were the absolute increase in curve severity, the percentage of curves that progressed beyond 6 degrees and 10 degrees thresholds, and the percentage of patients who underwent surgery. RESULTS: Age, Risser stage, curve size, and time braced and observed did not differ among groups. Mean progression of the curve during bracing was 1.1 degrees with thoracolumbosacral orthosis, 6.5 degrees with the Charleston brace, and 6.3 degrees with the Milwaukee brace (P = 0.012; analysis of variance). Proportion of patients with more than 10 degrees of curve progression was 14% with thoracolumbosacral orthosis, 28% with the Charleston brace, and 43% with the Milwaukee brace (P = 0.017; chi-square). The proportion of patients who underwent surgery was 18% with thoracolumbosacral orthosis, 31% with the Charleston brace, and 23% with the Milwaukee brace (P = 0.26; chi-square). CONCLUSIONS: The thoracolumbosacral orthosis was superior at preventing curve progression in adolescent idiopathic scoliosis.     

A comparison of radiographic and electrogoniometric angles in adolescent idiopathic scoliosis

STUDY DESIGN: This was a cross-sectional study of a consecutive group of adolescent patients presenting to a scoliosis clinic for routine assessment or monitoring of their scoliosis, excluding postsurgical patients. SUMMARY OF BACKGROUND DATA: In vitro studies suggested electrogoniometry could be useful in the evaluation of scoliosis. No prior in vitro study had been performed. OBJECTIVES: To determine the reliability and validity of an electrogoniometric instrument, the Metrecom Skeletal Analysis System, in assessing adolescent idiopathic scoliosis. METHODS: Thirty-one patients were examined, radiographed, and scanned with the Metrecom Skeletal Analysis System twice by two different examiners. The magnitudes of the curves derived from the Metrecom Skeletal Analysis System scans were compared with each other and with the Cobb angles measured from standing radiographs. RESULTS: The intraclass correlation coefficient (a measure of agreement, ranging from 0 to 1, where 1 represents complete agreement) for the intraexaminer reliability of the Metrecom Skeletal Analysis System ranged from 0.71 to 0.83. The interexaminer reliability intraclass correlation coefficient of the Metrecom Skeletal Analysis System was 0.58, with a mean difference between examiners of 5.5 degrees (SD = 5 degrees), and limits of agreement (mean difference +/-2 SD) ranging from -4.5 degrees to 15.6 degrees. The Metrecom Skeletal Analysis System and the radiographically derived Cobb angle correlation was 0.64, but the mean difference between the methods was 3.7 degrees (SD = 11.1), with limits of agreement from 18.4 degrees to 25.9 degrees. CONCLUSION: The Metrecom Skeletal Analysis System does not provide sufficient clinical precision to substitute for the Cobb angle measured from spinal radiographic measurements in the management of adolescents with scoliosis.     

Experimental studies for the surgical correction and fixation of dorsal spine deformities

One of the specific features of the scoliosis operations with a posterior approach is that both the correction of the deformity and then the maintaining of the corrected situation are carried out with the help of the implants. With the currently applied systems based on the CD principle it is still difficult to control the rotational component of the scoliotic curve. To complement the systems based on the CD principle, we have developed an implant family whose application makes the correction of the dorsal deformity generally simplier and derotation more effective. Our method is based on the application of such hooks which, linked to the longitudinal rods and hooked on both transverse processes of the instrumented vertebrae, transmit the concerted forces exerting their influence in the direction of the correction. Depending on their symmetrical relations, the hooks are capable of tilting in the frontal plane and derotating in the horizontal plane simultaneously, in the direction of our choice. The stability and applicability of the hooks were tested in implants into cadavers, and then the intimate relations of the implants were examined by means of radiological tests and dissection on instrumented specimens. On the basis of our results, the implants can already be used in clinical practice.     

Etiology of idiopathic scoliosis. Computational study

A review of the literature on the mechanical aspects of the etiology for idiopathic scoliosis reveals that the buckling hypothesis has been presented as a purely mechanical phenomenon. In an attempt to confirm the buckling hypothesis, a numerical simulation of growth and the resulting buckling phenomena was done by means of finite element analysis. It previously was observed that growth was induced in the T4 to T10 vertebrae. Only the sacrum was assumed to be stationary. From the growth analysis, a deformation process that mitigated thoracic kyphosis was obtained as observed in healthy children during early adolescence. From the buckling analysis, the first to the fourth buckling modes that correspond to the first side bending, first forward bending, first rotation, and second side bending modes were obtained. The shape of the fourth buckling mode (second side bending mode) was in good agreement with the clinical shape. Considering the potential for controlling these modes by posture change, it is concluded that the second bending mode in the coronal plane is one of the most likely etiologic candidates in the mechanics of thoracic idiopathic scoliosis.     

The effects of perioperative blood salvage and autologous blood donation on transfusion requirements in scoliosis surgery

Fifty consecutive cases of surgical instrumentation and fusion for adolescent idiopathic scoliosis were prospectively studied to test the hypothesis that the use of predonated autologous blood combined with judicious perioperative blood salvage could decrease the amount of homologous blood needed. All cases had posterior instrumentation and fusion. Nineteen patients had their rib prominence resected with an average of 4.8 ribs per patient. Our protocol called for perioperative blood salvage with the cell saver and reinfusion of postoperative drained blood if more than 300 ml were drained in 4 hours. Two units of predonated autologous blood was made available. Hypotensive anesthesia and meticulous hemostasis kept the blood loss to a minimum. The average total blood loss was 1,055 ml. Blood loss per segment was 91 ml with an average of 11 segments fused per patient. Patients with rib resection had a blood loss of 1,105 ml, while those without had a blood loss of 955 ml. The cell saver blood returned per case was 391 ml with the hematocrit of the product averaging 46%. Twelve patients were reinfused an average of 300 ml of the postoperative drained blood. The predonated autologous blood was used as part of the intraoperative fluid management. In no patient was homologous blood needed. The average starting hematocrit was 35.6%, with the hematocrit at discharge (seventh day) being 32.4%. There were no complications or blood transfusion reactions. Our results suggest that judicious perioperative blood management may decrease the need for homologous blood transfusion in selected posterior idiopathic scoliosis surgery.     

Somatosensory- and motor-evoked potential monitoring without a wake-up test during idiopathic scoliosis surgery. An accepted standard of care

STUDY DESIGN: This was a retrospective study of 500 patients undergoing corrective surgery between 1987 and 1997 for spinal deformity caused by idiopathic scoliosis. OBJECTIVES: To report the sensitivity and specificity of somatosensory-evoked and neurogenic motor-evoked potentials monitoring and the requirements for an intraoperative wake-up test for all idiopathic scoliosis surgeries at a single institution. SUMMARY OF BACKGROUND DATA: Intraoperative monitoring is recommended for use during corrective spinal surgery. Accepted monitoring standards and requirements for an intraoperative wake-up test are still debated. METHODS: The study group consisted of 500 patients undergoing corrective surgery for idiopathic scoliosis between 1987 and 1997. All patients were monitored using somatosensory-evoked and neurogenic motor-evoked potential techniques, using a standard protocol developed at this institution. RESULTS: The false-positive rate (significant data change without postoperative neurologic deficit) was 0.014% (n = 7). The true-positive rate (degradation of data that met warning criteria, with a corresponding postoperative neurologic deficit) was 0.004% (n = 2). No false-negative results (normal data during with a postoperative neurologic deficit) were seen. The sensitivity of combined somatosensory-evoked and neurogenic motor-evoked potential data in predicting neurologic status was 98.6%, and the specificity of normal data predicting normal findings in a neurologic examination was 100%. CONCLUSION: Combined somatosensory-evoked and neurogenic motor-evoked potentials monitoring during idiopathic scoliosis surgery represents a standard of care that obviates the need for an intraoperative wake-up test when reliable data are obtained and maintained.     

The correlation of idiopathic lumbar scoliosis and lumbar lordosis

A definite correlation exists between the presence of idiopathic lumbar scoliosis and hyperlordosis of the lumbar spine. Present data do not reveal whether hyperlordosis constitutes an element which makes a "spine at risk" for developing scoliosis. However, the presence of an extreme lordosis suggests that in any comprehensive plan of treatment of idiopathic lumbar scoliosis, provision should be made for correction of severe deformities of the lumbar spine.