Fusion For Idiopathic Scoliosis Research Articles

The evaluation of short fusion in idiopathic scoliosis

Background:Selective thoracic fusion in type II curve has been recommended by King et al. since 1983. They suggested that care must be taken to use the vertebra that is neutral and stable so that the lower level of fusion is centered over the sacrum. Since then there has been the trend to do shorter and selective fusion of the major curve. This study was conducted to find out whether short posterior pedicle instrumentation alone could provide efficient correction and maintain trunk balance comparing to the anterior instrumentation.Materials and Methods:A prospective study was conducted during 2005-2007 on 39 consecutive cases with idiopathic scoliosis cases King 2 and 3 (Lenke 1A, 1B), 5C and miscellaneous. Only the major curve was instrumented unless both curves were equally rigid and of the same magnitude. The level of fusion was planned as the end vertebra (EVB) to EVB fusion, although minor adjustment was modified by the surgeons intraoperatively. The most common fusion levels in major thoracic curves were T6–T12, whereas the most common fusion levels in the thoraco-lumbar curves were T10–L3. Fusion was performed from the posterior only approach and the implants utilized were uniformly plate and pedicle screw system. All the patients were followed at least 2 years till skeletal maturity. The correction of the curve were assessed according to type of curve (lenke IA, IB and 5), severity of curve (less than 450, 450-890 and more than 900), age at surgery (14 or less and 15 or more) and number of the segment involved in instrumentation (fusion level less than curve, fusion level as of the curve and fusion more than the curve)Results:The average long-term curve correction for the thoracic was 40.4% in Lenke 1A, 52.2% in Lenke 1B and 56.3% in Lenke 5. The factors associated with poorer outcome were younger age at surgery (<11 years or Risser 0), fusion at wrong levels (shorter than the measured end vertebra) and rigid curve identified by bending study. However, all patients had significant improved trunk balance and coronal hump at the final assessment at maturity. Two patients underwent late extension fusion because of junctional scoliosis.Conclusions:With modern instrumentations, the EVB of the major curve can be used at the end of the instrumentation in most cases of idiopathic scoliosis. In those cases with either severe trunk shift, younger than 11 years old, or extreme rigid curve, an extension of one or more levels might be safer. In particular situations, the concept of centering the lowest vertebra over the sacrum should be adopted.

Risk factor analysis of proximal junctional kyphosis after posterior fusion in patients with idiopathic scoliosis

Study design A retrospective analysis of 150 adolescents who underwent spinal fusion for idiopathic scoliosis. Objective To analyse the incidence of the postoperative proximal junctional kyphosis after posterior fusion to the upper thoracic vertebra in adolescents with idiopathic scoliosis and to explore its risk factors. Summary of background data The reported incidence of the proximal junctional kyphosis after the posterior fusion in patients with idiopathic scoliosis varies depending on surgical methods and strategies adopted by the institution. Methods The changes in the Cobb angle of the proximal junctional kyphosis on the lateral spine X-ray were measured and the presence of PJK was recorded. The risk factors were screened using statistical analysis. Results PJK occurred in 35 out of 123 patients with an overall incidence of 28%. Among them, 28 patients (80%) experienced PJK within 1.5 years after surgery. The PJK-inducing factors included greater than 10° intraoperative decrease in thoracic kyphosis, thoracoplasty, the use of a pedicle screw at the top vertebra, autogenous bone graft and fusion to the lower lumbar vertebra (below L2). Conclusions There is a high incidence of postoperative proximal junctional kyphosis after posterior fusion to the upper thoracic vertebra within 1.5 years after surgery in adolescents with idiopathic scoliosis. In order to reduce its incidence, the risk factors for PJK should be carefully evaluated before surgery.

Adjacent Segment Disease After Instrumented Fusion for Idiopathic Scoliosis

A literature-based review. To summarize the clinical and morphologic findings leading to diagnosis, the etiologic factors, and principles of management. To identify the strengths and limits of past studies. There are considerable controversies regarding etiologic factors, diagnosis, and management of adjacent segment disease in patients instrumented for idiopathic scoliosis. Summarized is past literature and, to some extent, personal experience of the authors. Several factors participating to this complex pathophysiology are reported. The clinical presentation, occurring after symptom free interval, can vary, and modern morphologic investigations help for diagnosis. Management is often surgical and remains challenging. Long-term consequences of spinal fusions are now major concerns, especially in young patients undergoing surgical correction for idiopathic scoliosis. Adjacent segment disease is defined by a combination of clinical symptoms and morphologic findings. Several etiologic factors have been reported, but need to be further studied to prevent and improve the surgical management of this complication.

182. Extension of Prior Idiopathic Scoliosis Fusions to the Sacrum: A Matched Cohort Analysis of 65 Patients with Minimum 2-Year Follow-Up: Can Bone Morphogenic Protein Improve Outcomes?

BACKGROUND CONTEXT: Patients who undergo fusion for the treatment of idiopathic scoliosis during their adolescent or young adult years can develop age related degeneration and progressive deformity distal to their existing fusions. Extension of the fusion to the sacrum is sometimes required for treatment. A high rate of complications, including a 37% rate of pseudoarthrosis, has been reported in the literature. (Islam et al, Spine 2002).

Revision Surgery After Primary Spine Fusion for Idiopathic Scoliosis

Retrospective case series. The objective of this study was to review the overall prevalence of, and indications for, reoperations after the index spine fusion for idiopathic scoliosis at our center. Spine fusions for idiopathic scoliosis are expected to be the final therapeutic intervention in management. In a recent publication in 2006, reoperations after index spine fusion for idiopathic scoliosis were reported in 12.9% of patients at a single institution (n = 1046). A spinal deformity database search at our center identified all primary anterior, posterior, and circumferential spinal fusions performed for idiopathic scoliosis (1985-2003). A total of 1057 patients were identified whose mean age was 14.4 years (7-22 years) with minimum 2 year follow-up after index surgery. Study cohort consisted patients who underwent reoperation for any reason after index fusion procedure. Of the 1057 spinal fusions for idiopathic scoliosis, 41 (3.9%) underwent reoperation. Primary surgeries were: 11 anterior spinal fusions, 25 posterior spinal fusions, and 5 circumferential spinal fusions. Mean follow-up was 5.7 years (2-10.8). Forty-seven additional procedures were performed during 46 reoperations at an average of 26 months after index procedure (1 week-73 months). Of the 47 reoperations, 20 (43%) were revision spinal fusions (for pseudarthroses, uninstrumented curve progression or junctional kyphosis), 16 (34%) because of infections (5 acute, 11 chronic), 7 (15%) for implant removals due to pain and/or prominence (4 complete, 3 partial), 2 (4%) were revision of loosened implants, and 2 (4%) were elective thoracoplasties. This study documented a 3.9% overall reoperation rate at our medical center, a 3-fold lower reoperation rate than the previously reported 12.9%. The most common reoperations were for infections (34%), pseudarthroses (26%), and postoperative curve progression of the adjacent unfused spine (17%).

Superior Vena Cava Compression During Posterior Spinal Fusion for Idiopathic Scoliosis

Hogan, Kathleen A. MD1; Harvey, Susan C. MD1; Conway, William F. MD, PhD1; DeRosimo, John F. MD1; Gross, Richard H. MD1 Author Information

Selection of Fusion Levels in Adolescent Idiopathic Scoliosis Using Fulcrum Bending Prediction

A prospective study of 50 consecutive patients undergoing selective thoracic fusion for idiopathic scoliosis with minimum 2 year follow-up. We aim to establish the validity and safety of a new strategy using fulcrum bending (FB) radiographs and the inherent flexibility of the curve to select fusion levels for King type 2 and 3 curves (Lenke 1a, 1b, and 1c). The purpose of this new strategy is to preserve motion segments compared to the traditional method of selecting fusion levels. The aim of fusion in idiopathic scoliosis is to achieve a balanced spine with the shortest fusion preserving motion segments particularly in the lumbar spine. Conventional strategies for choosing fusion levels have been based on the standing radiographs and have not taken into account the flexibility of the curve. We followed 50 consecutive patients who underwent selective thoracic fusion for King 2 and 3 curves (Lenke 1a, 1b, and 1c). The fusion levels were chosen based on our new strategy using the FB radiograph. Twenty-five patients were fused using a hook system and 25 with a hybrid system of hooks and screws. All patients were observed until skeletal maturity and a minimum of 2 years. The curve correction, trunk shift, radiographic shoulder height, list were recorded at the preoperative stage, postoperative stage, and final follow-up. The patients had an average age of 15.4 years. The average preoperative Cobb angle was 55.4 degrees and final follow-up Cobb angle for the primary curve was 24.1 degrees, with no difference between the 2 groups. With the new strategy, we were able to save levels in 31 patients (62%), compared to the conventional method of selecting the lowest instrumented vertebra. There was a statistically significant difference in the correction of the fusion mass Cobb angle between the hook and hybrid groups. There was significant improvement in the trunk shift after surgery. Ninety-six percent of patients had balanced or minimally imbalanced shoulders at final follow-up. Three patients had tilting of the vertebra below the fusion mass into the primary curve that did not progress at skeletal maturity. The new objective strategy for determining fusion levels using FB radiographs is safe and effective. With considering the flexibility of the curve, we are able to save levels distally in over 60% of patients. This strategy takes into account the power of modern instrumentation.

The Role of Amicar in Same-Day Anterior and Posterior Spinal Fusion for Idiopathic Scoliosis

A retrospective study of the effectiveness of Amicar (epsilon aminocaproic acid). Evaluate the effectiveness of Amicar in decreasing perioperative blood loss and transfusion requirements in same-day anterior (ASF) and posterior spinal fusion (PSF) with segmental spinal instrumentation (SSI) for idiopathic scoliosis. Preliminary prospective, prospective randomized double-blind, and fibrinogen studies have demonstrated Amicar to be effective in decreasing perioperative blood loss in patients with idiopathic scoliosis undergoing PSF with SSI. Increased fibrinogen secretion is a possible explanation. There were 73 consecutive patients divided into 3 study groups based on the administration of Amicar: Group 1 (n = 16), no Amicar; Group 2 (n = 18), Amicar for the PSF with SSI only; and Group 3 (n = 39), Amicar for both ASF and PSF with SSI. All patients were managed using the same general anesthesia technique, intraoperative procedure, postoperative care path, and indications for transfusion (hemoglobin <7 g/dL). Total perioperative blood loss (estimated intraoperative blood loss for both procedures and measured postoperative chest tube and PSF wound suction drainage) and total transfusion requirements between groups were compared using one-way ANOVA. There were statistically significant decreases in mean estimated intraoperative PSF with SSI, total perioperative blood loss, and transfusion requirements in the 2 Amicar groups. However, Amicar had no significant effect on estimated intraoperative ASF blood loss, chest tube drainage, or PSF wound suction drainage. Total perioperative blood loss and transfusion requirements (cell saver, autologous, directed, and allogeneic blood) were: 3442.8 +/- 1344.0 mL and 1537.1 +/- 905.1 mL in Group 1; 2089.8 +/- 684.0 mL and 485.2 +/- 349.8 mL in Group 2; and 2184.1 +/- 1163.7 mL and 531.5 +/- 510.5 mL in Group 3. There were no Amicar related complications. Amicar was highly effective in decreasing total perioperative blood loss and transfusion requirements in same-day ASF and PSF with SSI for idiopathic scoliosis. It results in less preoperative autologous blood donation, perioperative blood transfusion, costs, and potential transfusion-related complications. It was most effective in decreasing intraoperative estimated PSF with SSI blood loss. It had no significant effect during the ASF, postoperative chest tube, or PSF wound suction drainage. We now recommend that it be used for the PSF with SSI procedure only.

Inpatient complications, mortality, and discharge disposition after surgical correction of idiopathic scoliosis: a national perspective

Background context Information about complications and mortality after surgery for correction of idiopathic scoliosis has been largely derived from single-institution series. Regional or national studies have been lacking. Purpose To report inpatient mortality, complications, and discharge disposition after surgical correction of idiopathic scoliosis on a national level. Study design Retrospective cohort study using National Inpatient Sample (NIS) administrative data. Patient sample All patients in the NIS with the primary diagnosis of idiopathic scoliosis who underwent a spinal fusion between 1993 and 2002 were included. Outcome measures Inpatient complication rate, mortality rate, and adverse outcome defined by death or discharge to institution other than home. Methods Outcome measures were abstracted from the NIS. Univariate and multivariate analyses were performed to analyze the effects of patient and hospital characteristics on outcome measures. Results The NIS was used to identify 51,911 patients who underwent spinal fusion for idiopathic scoliosis in the United States from 1993 to 2002. The total inhospital complication rate was 14.9% for pediatric patients and 25.1% for adult patients. The inhospital mortality rate was 0.17% and 0.40% for pediatric and adult patients, respectively. Adverse outcome was noted in 2.3% of pediatric patients and 20.4% of adult patients. Pulmonary and postoperative hemorrhages/hematomas were the most common complications reported. Multivariate analysis for complications showed that morbidity was significantly lower for pediatric patients (odds ratio [OR]=0.80; confidence interval [CI]=0.68–0.94) and female patients (OR=0.77; CI=0.68–0.88). Patients with a preoperative comorbidity were 1.53 (CI=1.32–1.76) times more likely to develop a complication. A single postoperative complication increased the mean length of stay by more than 2 days and increased the mortality rate, adverse outcome, and hospital charges significantly. Conclusions We have provided a national perspective on inpatient complications, mortality, and discharge disposition after spinal fusion for idiopathic scoliosis in the United States. The significant negative effects of postoperative complications on mortality and resource utilization have been demonstrated. Furthermore, we have identified adult age, male gender, and preoperative comorbidity as important risk factors and defined their impact on patient outcomes.

007—Pain Trajectory Following Spinal Fusion for Idiopathic Scoliosis

007—Pain Trajectory Following Spinal Fusion for Idiopathic Scoliosis

002—Incidence of Constipation and Abdominal Pain Following Spinal Fusion for Idiopathic Scoliosis

002—Incidence of Constipation and Abdominal Pain Following Spinal Fusion for Idiopathic Scoliosis

Video-Assisted Thoracoscopic Surgery in Idiopathic Scoliosis

Retrospective review of patients with idiopathic scoliosis who underwent same-day or staged anterior and posterior spinal fusion and segmental spinal instrumentation. Evaluation of our learning curve with video-assisted thoracoscopic surgery (VATS) with respect to operative time, blood loss, and complications in patients with idiopathic scoliosis. VATS is a minimally invasive alternative to thoracotomy in the management of idiopathic scoliosis. An increased or steep learning curve has been described in the initial application of this technique. We began performing VATS in 1998. We compared our first 25 consecutive VATS patients (Group 2) and subsequent 28 consecutive VATS patients (Group 3) to our previous 16 consecutive patients (Group 1) with a thoracotomy (1991-1998) for idiopathic scoliosis. Training at a sponsored regional course was obtained before performing our first VATS procedure. VATS allowed more disc to be excised in Group 2 (4.5 +/- 1, 5.7 +/- 1, and 4.4 +/- 1 discs in Group 1, Group 2, and Group 3, respectively) and significantly decreased the anterior operative time (215 +/- 33, 260 +/- 56, and 177 +/- 47 minutes) and time per individual disc excision (50 +/- 13, 47 +/- 12, and 41 +/- 12 minutes), while providing comparable correction of the thoracic deformity (67% +/- 12%, 66% +/- 10%, and 70% +/- 13% correction). There was no increase in estimated intraoperative anterior blood loss (228 +/- 213, 183 +/- 136, and 211 +/- 158 mL), estimated blood loss per disc excised (51 +/- 42, 34 +/- 29 and 48 +/- 37 mL), or complications in the VATS groups. Complications were primarily pulmonary and resolved with medical therapy. Postoperative chest tube drainage (855 +/- 397, 462 +/- 249, and 561 +/- 261 mL) and total perioperative anterior blood loss (1083 +/- 507, 647 +/- 309, and 773 +/- 308 mL) were significantly decreased in the VATS groups, but this was attributed to the use of Amicar. VATS is an effective procedure for anterior spinal fusion in idiopathic scoliosis. The learning curve is short, provided appropriate training is obtained.

Predictability of the spontaneous lumbar curve correction after selective thoracic fusion in idiopathic scoliosis

In this study we tried to achieve a better understanding of the biodynamic mechanism of balance in the scoliotic spine. Therefore we focused on the pre- and postoperative spine of patients with idiopathic scoliosis with a primary thoracic curve and a secondary lumbar curve. Several studies showed that the lumbar curve spontaneously corrects and improves after selective thoracic fusion. We try to understand and describe this spontaneous compensatory lumbar curve correction after selective thoracic correction and fusion. We performed a retrospective examination of pre- and postoperative radiographs of the spine of 38 patients with idiopathic scoliosis King type II and III. Frontal Cobb angles of the thoracic and lumbar curves were assessed on pre- and postoperative antero-posterior and side bending radiographs. We determined the postoperative corrections of the thoracic and lumbar curves. Relative (%) corrections and correlations of the postoperative corrections were calculated. The group was divided in three subgroups, depending on lumbar curve modifier, according to Lenkes classification system. The calculations were done for the whole group as for each subgroup. As expected, significant correlations were present between the relative correction of the main thoracic and the lumbar curve (mean R = 0.590; P = 0.001). The relation between relative thoracic and lumbar correction decreased with the lumbar modifier type. This study shows a highly significant correlation between the relative corrections of the main thoracic curve and the lumbar curve after selective thoracic fusion in idiopathic scoliosis. This correlation depends on lumbar curve modifier type. This new classification system seems to be of great predictable value for the spontaneous correction of the lumbar curve. Depending on the curve-type, a different technique for predicting the outcome should be used. The lumbar curve correction does not occur throughout the whole lumbar curve. Most correction is achieved in the upper part of the curve. The distal lumbar curve seems to be more rigid and less important in the spontaneous curve correction.

Repeat Surgical Interventions Following “Definitive” Instrumentation and Fusion for Idiopathic Scoliosis

A retrospective chart review was performed on all idiopathic scoliosis patients treated with instrumented spinal fusion over a 15-year period. To provide an experience from a single institution over a prolonged time period. The goal was to determine the frequency of repeat surgical interventions following the "definitive" spinal fusion surgery and identify the factors responsible for these reoperations. Instrumented spinal fusion remains the standard of care in the surgical management of idiopathic scoliosis. This surgery is considered a "definitive" procedure where, barring a complication, no additional surgical procedures are planned. Although many studies have reported the frequency of specific complications following spinal fusion, little information currently exists regarding the cumulative average of these repeat surgical interventions that occur following these "definitive" procedures. Surgical logs were reviewed on all patients who had an instrumented spinal fusion for idiopathic scoliosis from January 1988 through December 2002. All subsequent surgical interventions on these patients were then identified from the logs through December 2004. Pertinent information was gleaned from surgical logs and patient charts to provide details for these reoperations. A total of 1,046 patients underwent an instrumented spinal fusion for idiopathic scoliosis: 809 had a posterior-only fusion, 228 had an anterior-only fusion, and 9 had a combined anterior/posterior spinal fusion. A total of 172 repeat surgical interventions were performed in 135 patients (12.9%). Of these 135 patients, 29 patients (21.5%) had two or more separate procedures performed. The most common reasons for reoperation were infection, symptomatic implant, and pseudarthrosis. Patients who had posterior fusions had a significantly higher rate of reoperation than patients who had anterior fusions (14.0% vs. 9.3%). Reoperations due to infections and symptomatic implants occurred with significantly higher frequency in the posterior spine fusion group compared with those with anterior spinal fusion. No differences in rates of reoperation for pseudarthrosis were noted between posterior and anterior fusion groups. Repeat surgical interventions are relatively common following these supposedly definitive surgical procedures. The most common reasons for return to surgery are infection, symptomatic implant, and pseudarthrosis.

More than 20-year follow-up Harrington instrumentation in the treatment of severe idiopathic scoliosis

On the basis of our own experience, we would like to support the results reported in the article “Minimum 20-year follow-up results of Harrington rod fusion for idiopathic scoliosis” [2]. The number of patients that we evaluated and the duration of their follow-up are almost the same as those reported in the article. The only difference is that we evaluated only the patients with severe idiopathic scoliosis and that there was a difference in the application of Harrington rod. It is obvious from the report, especially from Fig. 3, that the investigators did not contour the Harrington rod in the sagittal plane. We, on the other hand, always did it. One of our authors (M.P.), i.e., the one who operated on all the patients, used French rod bender to contour Harrington rod in sagittal plane depending on the length of spondylodesis. He secured the round end of the rod in the lower laminar hook and then squeezed the hook, using special pincer. Thus, the round end of the rod was fixated in the hook, which prevented the rotation during distraction. The first author learned this procedure working with Dr Pierre Stagnara. With respect to the application of the autologous bone transplant, postoperative immobilization, and rehabilitation, the procedure were followed was the same as the one described by the authors of the article. Between 1980 and 1983, 25 patients, 19 women and 6 men with severe idiopathic scoliosis (Cobb angle ≥70°) were treated with posterior spinal arthrodesis and Harrington instrumentation at our Department. The mean age of patients at the time of intervention was 23 years, ranging from 13 to 31 years. The follow-up lasted 22 years and 5 months on average (range 22–25 years) and none of the patients were lost. Two patients had a type I curve, 5 had a type II curve, 11 had a type III curve, 5 had a type IV curve, and 2 had a type V curve according to the classification of King et al. [1]. All patients were treated by Stagnara operative technique and Stagnara postoperative protocol [3]. A junior orthopedic surgeon who did not assist at the operations evaluated all the patients. The preoperative Cobb angle of the primary curve was 87° on average (range 74°–125°). Postoperatively, the curve was 51° on average (range 35°–85°), i.e., the obtained correction of the curve was 40% (range 15–58%). Only three patients had to undergo reoperation, one because of pseudarthrosis and two because the caudal hook dislodged. There were no neurological complications. At the most recent follow-up visit, an average loss of correction was 10° (range 0°–22°). The average spine score was 84 points (range 26–98 points). The average level of pain on the analog scale was 2.6 points (range 0–7.2 points). Actually 23 patients are full-time workers and two patients are employed as part-time. None of our patients had a flat back syndrome. In our opinion, it is due to Harrington rod modeling and achieving the balance of the spine in sagittal plane (Fig. 1). Fig. 1 Standing sagittal view radiograph with contured Harrington rod, 23-year follow-up Comparing our results with those reported in the article, we concluded that they were almost identical. It should be mentioned, however, that the primary scoliotic curve was reduced practically by the same percentage with respect to the preoperative angle in both groups of patients. Both studies showed that the long-term effect of Harrington instrumentation can be successful even in severe and adult idiopathic scoliosis. In our opinion, it is possible to achieve grace to Stagnara operative technique (solid spondylodesis, sagittal configuration of the Harrington rod, and rib resection) and Stagnara postoperative treatment.

Cobalt Chromium Sublaminar Wires for Spinal Deformity Surgery

Biomechanical analysis and retrospective chart review. To determine the mechanical properties of cobalt chromium alloy wires and review the clinical application of the wires as sublaminar implants to correct spinal deformity. Sublaminar wires are commonly used as anchors in spinal deformity surgery. In stainless steel instrumentation systems, single strand wires (Luque wires) may be retightened over time to take advantage of stress relaxation while correcting spinal deformity. Because of the mechanical properties of titanium, solid titanium wires are not used as sublaminar wires. Cobalt chromium alloy is a titanium compatible alloy that can be twisted in a similar fashion to stainless steel sublaminar wires. Comparative tensile tests were performed using cobalt chromium alloy wires and Luque stainless steel wires. In addition, 22 consecutive posterior spinal fusions for idiopathic scoliosis were performed using cobalt chromium alloy wires as sublaminar implants. Yield and ultimate tensile loads for the cobalt chromium alloy wires are on average 66% (P < 0.001) and 60% (P < 0.001) higher, respectively, than those for the steel wires. Mean preoperative thoracic curve for patients with idiopathic scoliosis was 56 degrees +/- 15 degrees , which corrected to 19 degrees +/- 11 degrees (67% correction, P < 0.001) when cobalt chromium alloy wires were used as sublaminar implants. Mean preoperative lumbar curve was 52 degrees +/- 14 degrees , which corrected to 17 degrees +/- 8 degrees (68% correction, P < 0.001). There were no instrumentation failures, neurologic complications, or infections. The advantages of cobalt chromium alloy wire over steel wire include greater tensile strength and titanium compatibility. Cobalt chromium alloy solid wires may be used as sublaminar implants with titanium spinal instrumentation with excellent clinical results.

Unusual presentation of osteoblastoma in a patient with idiopathic scoliosis after posterior spinal fusion

Few studies have described the diagnosis of osteoblastoma of the spine as a cause of scoliosis. These reports have described the tumor in conjunction with initial presentation of painful scoliosis. This case report presents a case of osteoblastoma 9 years removed from diagnosis and fusion of idiopathic scoliosis in the thoracic spine. To report the late presentation of an osteoblastoma of the thoracic spine 9 years after posterior spinal fusion for scoliosis. Case report. A 25-year-old man presented with thoracolumbar back pain and progressive neurological deficit 9 years after posterior spinal fusion for idiopathic scoliosis. Magnetic resonance imaging of the thoracic spine indicated the presence of a mass in the spinal canal causing cord compression. The patient underwent decompression with resection of the mass which was found to be an aggressive osteoblastoma. The patient enjoyed a full neurological recovery and has subsequently developed a recurrence at 13 months. We present osteoblastoma as a possible cause of low back pain and neurological deficit postfusion that should be considered in a differential diagnosis.

Screw Position After Double-Rod Anterior Spinal Fusion in Idiopathic Scoliosis

A retrospective evaluation of screw position after double-rod anterior spinal fusion in idiopathic scoliosis using computerized tomography (CT). To evaluate screw position and complications related to screw position after double-rod anterior instrumentation in idiopathic scoliosis. Anterior instrumentation and fusion in idiopathic scoliosis is gaining widespread use. However, no studies have been published regarding the accuracy of screw placement and screw-related complications in double-rod and double-screw anterior spinal fusion and instrumentation in idiopathic thoracolumbar scoliosis surgery. CT examinations were performed after surgery in 17 patients with idiopathic scoliosis. At each instrumented level, the position of the screw and the plate relative to the spinal canal, relative to the neural foramen, and relative to the aorta was measured. Complications related to screw position were registered. A total of 189 screws in 17 patients were evaluated. Malposition occurred in 23% (16 patients) of the total number of screws. Three screws (2 patients) were partially in the spinal canal (1%). This resulted in pain in the right leg in 2 patients. However, electromyography showed no abnormalities. At three levels (3 patients), there was contact between the instrumentation and the aorta. However, no vascular complications occurred. A total of 113 screws (10 patients) were placed under fluoroscopic control and 76 screws (7 patients) were placed without use of fluoroscopy. Less screw malposition was observed in the group in which fluoroscopic control was used (19% vs. 30%, not significant). Screw placement in double-rod anterior spinal fusion in idiopathic scoliosis seems to be technically demanding, and the use of fluoroscopic control results in less frequent malposition. The risk of neurologic and vascular complications is low.

The Effect of Scoliosis Fusion on Spinal Motion: A Comparison of Fused and Nonfused Patients With Idiopathic Scoliosis

Movement analysis of spinal motion. To compare spinal motion among females with normal spines, those with idiopathic scoliosis who had not had spinal fusion, and those who had undergone fusion for idiopathic scoliosis. Previous reports have documented loss of spinal motion following fusion for idiopathic scoliosis in adolescents and adults. To our knowledge, comparison to control groups both with and without scoliosis that have not had spinal fusions has not been performed to date. A total of 91 females between the ages of 15 and 28 years underwent computerized movement analysis. There were 34 fused patients, 32 unfused patients, and 25 healthy controls. The fused patients were divided into 3 groups: (1) 21 patients who had thoracic fusions that extended distally to T11, T12, or L1; (2) 6 patients with thoracic fusions ending at L2; and (3) 7 patients with thoracolumbar or lumbar fusions extending to L3 or L4. Marker triads were placed at C7-T1, T12-L1, and on the pelvis. Forward bend, extension, and left and right lateral bend were measured and divided into thoracic and lumbar motion. There was no difference in any motion between the control and unfused groups. There was overall 25% less total spinal motion in the surgical groups compared to the unfused group. Patients who had thoracic fusions had diminished thoracic motion, especially lateral bending, whereas those who had lumbar fusions had the least lumbar motion, particularly on forward bend and lateral bend maneuvers. There was no compensatory hypermobility of the unfused segments in the surgical group. Diminished spinal motion can be measured in patients who have had spinal fusions. Although stiffness in the operated curves should be expected, compensatory hypermobility in the unfused segments does not occur, resulting in a net loss of flexibility compared to controls.

Spontaneous Correction and Derotation of Secondary Curves After Selective Anterior Fusion of Idiopathic Scoliosis

Clinical, rasterstereographic, and radiographic evaluation of spontaneous vertebral derotation of secondary curves in idiopathic scoliosis following selective anterior correction and fusion of the primary curve. To quantify spontaneous vertebral derotation in secondary curves after selective anterior correction with attention to cosmetic outcome. While the derotational effect of anterior instrumentation techniques on the instrumented curve is well understood, there is a paucity on data of the rotational behavior of the noninstrumented secondary curves. A total of 43 patients with idiopathic scoliosis (16 with thoracic curves in group 1 and 27 with thoracolumbar/lumbar curves in group 2) underwent selective anterior instrumentation. Vertebral rotation was analyzed before surgery and, on average, 20 months after surgery using digital radiometric rotation analysis, back shape analysis with rasterstereography, and scoliometer measurement. In Group 1, there was a significant spontaneous vertebral derotation of the secondary lumbar curves by 14.2% (range from 12.7 degrees to 10.9 degrees) in the digital radiometric rotation analysis, surface derotation amounted to 49% (range from 9.6 degrees to 4.9 degrees) in the rasterstereography, and to 70% in the clinical scoliometer measurement (range from 8.0 degrees to 2.4 degrees ). In group 2, there was an increase of rotation of the noninstrumented secondary thoracic curves by 30% (range from 5.0 degrees to 6.5 degrees ) in digital radiometry, by 32.9% in the rasterstereography (range from 8.5 degrees to 11.3 degrees), and a 28.3% increase in scoliometer measurement (range from 6.0 degrees to 7.7 degrees). Selective anterior instrumentation and fusion of primary thoracic curves results in satisfactory spontaneous vertebral and high surface derotation of the secondary lumbar curves. However, in primary thoracolumbar or lumbar curves, an increase of both vertebral and surface rotation of the secondary thoracic curve was noted. This increase can impair cosmetic outcome.