Primary Curve Correction Research Articles

Clinical outcomes of the traditional dual growing rod technique combined with apical pedicle screws in the treatment of early-onset scoliosis: preliminary results from a single center.

Limited control of an apical deformity is a major disadvantage in the traditional dual growing rod (TDGR) technique. Previous literature has reported the results of apical pedicle screw placement (APS) as an apical control technique in patients with early-onset scoliosis (EOS). However, the clinical outcomes, indications, and complications of the TDGR technique combined with APSs have not been well described. The purpose of this study was to evaluate the preliminary clinical outcomes of the TDGR technique combined with APSs in EOS patients. Clinical data of 12 patients with EOS who were treated with the TDGR technique combined with APSs at the index surgery at the authors' center from January 2010 to January 2020, with a minimum 2-year follow-up, were retrospectively reviewed. Indications for the use of APSs included 1) no vertebral segmentation failure, fused ribs, or multiple hemivertebrae at the apex; 2) at least 2 normal discs around the apex; and 3) proper development of apical pedicles on the convex side. Etiology, age at index surgery, number of lengthening procedures, follow-up duration, and complications were recorded. Radiographic measurements included Cobb angle, apical vertebral translation (AVT), apical vertebral rotation (AVR), thoracic kyphosis, lumbar lordosis, spine height, and space available for the lung (SAL). The mean follow-up period was 4.0 ± 1.4 years, with a mean of 4.8 lengthening procedures per patient. The mean Cobb angle improved from 61.7° ± 10.4° to 19.9° ± 9.0° after the index surgery (19.6° ± 9.4° at the latest follow-up). The mean postindex AVT decreased to 16.8 ± 8.9 mm from a preindex AVT of 56.3 ± 9.7 mm and further improved to 13.6 ± 10.0 mm at the latest follow-up. The mean annual increases in T1-12 and T1-S1 height were 9.0 ± 4.7 mm and 13.9 ± 6.5 mm, respectively. The SAL improved from 0.91 to 1.04 at the latest follow-up. AVR improved significantly after the index surgery (p = 0.013), while minor deterioration was observed after repeat lengthening procedures. Five complications (2 implant related and 3 alignment related) occurred in 4 patients. For EOS patients with good flexibility (without segmentation failure or multiple hemivertebrae at the apex), the TDGR technique combined with APSs can improve primary curve correction, maintain good correction results, and allow continuous spine growth, which may reduce the risks of complications during lengthening treatment. More multicenter prospective studies with larger samples are needed to further validate the findings of this study.

No difference in postoperative complication rates or cardiopulmonary function for early versus late scoliosis correction in Duchenne muscular dystrophy

Given reduced rates of both pulmonary function decline and scoliosis progression with steroid treatment in Duchenne muscular dystrophy (DMD), the role of early scoliosis surgery has been questioned. The purpose of this study was to compare the postoperative complication rates of early versus late scoliosis correction in DMD. This study was a retrospective cohort, conducted at an academic tertiary level children's hospital. Patients with DMD who underwent posterior scoliosis correction, with preoperative pulmonary function testing [forced vital capacity (FVC)] were included and divided into two groups by preoperative curve angles: ≤ 45° and > 45°. The primary outcome variable was postoperative complications by Clavien-Dindo classification grading. Secondary outcome variables included postoperative complications occurring after the first 90days, age at surgery, duration of wheelchair dependency preoperatively, pulmonary function, steroid utilization, shortening fraction by echocardiogram, surgery duration, intensive care unit/hospital length of stay, days intubated, infection, and percent curve correction. Two-tailed t-test and Chi-square testing were used for analysis of patient factors and Clavien-Dindo complication grade, respectively. Thirty-one patients were included with a total follow-up of 8.3 ± 3.2years, 4.8 ± 2.2years post-spinal fusion. Steroid treatment (prednisone, deflazacort) was utilized for 21 (67.7%) patients. Primary curve correction was not different between groups (65.0% vs 71.4% [p = 0.37]). There were no significant differences in Clavien-Dindo classification grades between groups (p > 0.05). For the entire cohort, the overall complication rate was higher for patients with steroid treatment (61.9% vs 10.0% [p = 0.008]). Neither forced vital capacity nor fractional shortening on echocardiogram was different between groups at final follow-up (p = 0.6 and p = 0.4, respectively). The comparable risk of perioperative complications for early and late scoliosis correction supports a "watchful waiting" approach, whereby curves less than 45° can be carefully followed while cardiopulmonary function is maintained. Patients undergoing steroid treatment should be counseled regarding the higher risk of postoperative blood transfusion and deep wound infection. III Retrospective cohort.

Analysis of Posture Parameters in Patients with Idiopathic Scoliosis with the Use of 3D Ultrasound Diagnostics-Preliminary Results.

(1) Background: Idiopathic scoliosis occurs in 2 to 4% of children between 10 and 16 years of age. Due to the harmfulness of radiological examination, non-invasive devices, including the 3D ultrasound technology and Scolioscan apparatus, are more and more frequently used for postural diagnostics. The aim of the study was to analyze the parameters of posture in patients with idiopathic scoliosis with the use of 3D ultrasound diagnostics. (2) Methods: The study included 20 girls, aged 10 to 16 years, with double-curve idiopathic scoliosis (the value of primary curve ranged from 25–50°), types I and II according to King–Moe classification. On the basis of X-ray scan, the Cobb angle of primary and secondary curves was assessed, the skeletal maturity was evaluated with the Risser test, and the type of scoliosis was determined. The girls participated in a 3-week rehabilitation program. The examinations were performed before and after therapy. A scoliometer was used for measurements. Each of the participants underwent individual therapy. The three-plane approach to asymmetric exercises was based largely on positions that included primary curve correction with hypercorrection of the secondary curve. (3) Results: After the therapy, values of trunk rotation angles and the angle of scoliotic curvature of secondary curve were significantly lower than before the therapy, except for the value of the primary curve angle. The parameters measured by X-ray were significantly and positively related to the results obtained with the scoliometer and the scolioscan. (4) Conclusions: The application of therapy that takes into account summing parameters may prevent the deterioration of the secondary curve when treating patients with idiopathic scoliosis. The observed correlations between the parameters of the radiological examination, the scoliometer, and the scolioscan prove the possibility of their interchangeable application in the assessment of effects of the therapy. Three-dimensional ultrasound diagnostics may become an alternative to radiological examination in assessing the treatment effects of patients with idiopathic scoliosis.

Risk Factors for Proximal Junctional Kyphosis Following Surgical Deformity Correction in Pediatric Neuromuscular Scoliosis.

Single-center retrospective cohort analysis. The aim of this study was to evaluate risk factors associated with the development of proximal junctional kyphosis (PJK) in pediatric neuromuscular scoliosis (NMS). PJK is a common cause of reoperation in adult deformity but has been less well reported in pediatric NMS. Sixty consecutive pediatric patients underwent spinal fusion for NMS with a minimum 2-year follow-up. PJK was defined as >10° increase between the inferior end plate of the upper instrumented vertebra (UIV) and the superior end plate of the vertebra two segments above. Regression analyses as well as binary correlational models and Student t tests were employed for further statistical analysis assessing variables of primary and compensatory curve magnitudes, thoracic kyphosis, proximal kyphosis, lumbar lordosis, pelvic obliquity, shoulder imbalance, Risser classification, and sagittal profile. The present cohort consisted of 29 boys and 31 girls with a mean age at surgery of 14 ± 2.7 years. The most prevalent diagnoses were spinal cord injury (23%) and cerebral palsy (20%). Analysis reflected an overall radiographic PJK rate of 27% (n = 16) and a proximal junctional failure rate of 7% (n = 4). No significant association was identified with previously suggested risk factors such as extent of rostral fixation (P = 0.750), rod metal type (P = 0.776), laminar hooks (P = 0.654), implant density (P = 0.386), nonambulatory functional status (P = 0.254), or pelvic fixation (P = 0.746). Significant risk factors for development of PJK included perioperative use of halo gravity traction (38%, P = 0.029), greater postoperative C2 sagittal translation (P = 0.030), decreased proximal kyphosis preoperatively (P = 0.002), and loss of correction of primary curve magnitude at follow-up (P = 0.047). Increase in lumbar lordosis from post-op to last follow-up trended toward significance (P = 0.055). Twenty-seven percent of patients with NMS developed PJK, and 7% had revision surgery. Those treated with halo gravity traction or with greater postoperative C2 sagittal translation, loss of primary curve correction, and smaller preoperative proximal kyphosis had the greatest risk of developing PJK.Level of Evidence: 4.

Avoidance of "Final" Surgical Fusion After Growing-Rod Treatment for Early-Onset Scoliosis.

Definitive "final" surgical fusion is the common end point for growing-rod treatment of early-onset scoliosis. However, final surgical fusion may be unnecessary for patients who have reached skeletal maturity with good alignment. This study characterizes patients who completed growing-rod treatment but did not undergo final surgical fusion. Using a multicenter early-onset-scoliosis database, we identified 167 patients who received growing-rod treatment from 1995 through 2010, reached skeletal maturity, and had a minimum 2-year follow-up after their last surgery. Thirty patients did not undergo final surgical fusion (observation group) and were compared clinically and radiographically with 137 patients who did undergo final fusion (final surgical fusion group). No significant differences were found between the groups with regard to the age at which treatment was initiated (p = 0.127), distribution of diagnoses (p = 0.84), or number of lengthening procedures (p = 0.692). In the observation group, 26 patients retained the growing rods and 4 patients had them removed at the last surgery because of infection. The mean primary curve correction at the end of treatment was 48% (from an initial mean magnitude of 79° to a mean final curve of 41°) in the observation group compared with 38% (from 74° to 46°) in the final surgical fusion group. There was no significant difference in final curve magnitude (41° in the observation group and 46° in the final surgical fusion group; p = 0.182). The mean increase in trunk height was 30.5% in the observation group and 35% in the final surgical fusion group. The final trunk height in the observation group was not significantly less than that in the final surgical fusion group (p = 0.142). Because of progressive ankylosis, avoiding final surgical fusion at skeletal maturity is a viable option for patients treated with growing rods for all diagnostic subgroups of early-onset scoliosis who have satisfactory final alignment and trunk height, a minimal gain in length at the last distraction, and no clinical or radiographic evidence of implant-related problems. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

РЕЗУЛЬТАТЫ ХИРУРГИЧЕСКОГО ЛЕЧЕНИЯ ДЕТЕЙ С ВРОЖДЕННЫМ КИФОСКОЛИОЗОМ ГРУДОПОЯСНИЧНОЙ ЛОКАЛИЗАЦИИ

Objective. To analyze results of surgical treatment of children with congenital deformity of the thoracolumbar junction of the spine caused by isolated vertebral malformations. Material and Methods. Surgical treatment results in 37 patients aged 10 months to 12 years with congenital scoliosis caused by isolated lateral and posterolateral hemivertebrae in the thoracolumbar junction were analyzed. Magnitude of scoliosis before surgery was 18 to 52°, and that of kyphosis - 4 to 49°. Extirpation of the abnormal hemivertebra was performed in 33 (89.2 %) patients, and limited resection - in 4 (10.8 %). Results. Correction of scoliotic deformity after surgical treatment was 85.0% (0-26°), and correction of kyphotic component - 78.6 % (15-23°). Compensatory cranial and caudal counter curves leveled out at the background of the primary curve correction in all patients. Destabilization of instrumentation requiring repeat surgery was observed in two children. The findings showed the efficacy of the surgical treatment by main objective measures in 81.0 % of patients. Conclusion. Progression of congenital spinal deformity with lateral and posterolateral hemivertebrae in the thoracolumbar junction requires an early radical surgical correction with restoration of the spinal canal anatomy and physiological curves of the spine at the level of deformity. Hir. Pozvonoc. 2014; (1): 55-64.

COSTAL HUMPBACK RESECTION AS A FINAL STAGE OF IDIOPATHIC SCOLIOSIS SURGICAL TREATMENT

Objective. To analyse results of multistage surgical treatment of idiopathic scoliosis including costal humpback resection. Material and Methods. From 1996 to 2005 twenty girls with idiopathic scoliosis underwent spine deformity correction with Harrington distraction rod with Drummond interspinous wires (Group I) or with Cotrel – Dubousset Horizon Instrumentation (Group II). The final long-dated stage after correction of deformity included the costal humpback resection at the convex side only. Radiologic and topographic examinations were performed, and lung vital capacity parameter was used for lung function assessment. Patients answered the Russian version of SRS-24 questionnaire after correction and at each follow-up examination. Results. In Group I the mean curvature was 81.7° ± 26.7° (range, 55–107°) before correction and 34.5° ± 13.1° after correction (primary curve correction 57.8 ± 14.1 %). Mean correction loss in dynamics before resection was 8°, after resection 4.3°. In Group II the primary curve magnitude before correction was 87.4° ± 27.1° (range, 48–126°), after correction 42.7° ± 16.9° (primary curve correction 51.9 ± 9.6 %). Average correction loss in dynamics before resection was 3.5°, after resection 2.4°. Spirometric findings presented the following dynamics: lung vital capacity before resection was 1980 ml with mean early postoperative decrease by 16.8 % and subsequent reversion to the preoperative level or increase to 2010 ml. According to the questionnaire survey 100 patients gave the consent for surgery. Conclusion. Costal humpback resection as a cosmetic intervention improves the patient’s assessment of spine deformity surgical correction result.

Mini-open thoracoscopically assisted thoracotomy versus video-assisted thoracoscopic surgery for anterior release in thoracic scoliosis and kyphosis: a comparison of operative and radiographic results

Background context Combining anterior release and interbody fusion with posterior instrumented fusion is an accepted treatment for severe rigid spinal deformity. Video-assisted thoracoscopic surgery (VATS) and mini-open thoracoscopically assisted thoracotomy (MOTA) are two minimally invasive approaches to the thoracic spine. Both reduce surgical trauma, improve cosmesis and provide effective exposure for release and fusion. Published data and the authors' surgical experience have demonstrated that both techniques are equivalent in degree of release to traditional open thoracotomy, but no comparison between these two minimally invasive alternatives has been published to our knowledge. Purpose This study compared MOTA and VATS under the hypothesis that both result in similar corrections and comparable operative parameters when used in conjunction with posterior instrumented fusion. Study design/setting Retrospective chart review of consecutive case series by two surgeons. Patient sample Twenty-one (13 female, 8 male) patients underwent MOTA and 24 patients (17 female, 7 male) underwent VATS for anterior release, discectomy and fusion prior to posterior instrumented fusion. Outcome measures Outcomes were measured at a minimum of 1-year follow-up and included radiographic Cobb measurements and operative parameters. Methods The indications for surgery included rigid and severe scoliosis or thoracic kyphosis. Data collection included preoperative demographics, number of levels released, primary curve correction, operative time and blood loss. Data were normalized per number of levels released anteriorly. Statistical analysis of results was done using a two-sample t test assuming equal variances with two-tail p values less than .05. Results More anterior levels were operated on average in the VATS group (6.33 vs. 4.38 levels). Curve correction per anterior level released was similar in both groups (8.7 and 8.8 degrees/level for MOTA and VATS, respectively). There was a significant difference in operative time with MOTA averaging 131.7 minutes and VATS averaging 162.8 minutes. However, a comparison of the operative time per anterior level operated, approached statistical significance in favor of VATS (33.0 vs. 28.4 minutes, p=.08). There was no significant difference in estimated blood loss during the anterior portion of the surgeries. There was a trend toward decreased blood loss per operated level favoring VATS (68.4 vs. 38.9 cc, p=.09). Conclusions Both approaches resulted in corrections that compare favorably with open thoracotomy. We suggest that a factor in choosing between these two minimally invasive techniques is the number of thoracic levels requiring release. For four levels or less, MOTA provides an excellent alternative to standard thoracotomy. For five or more levels, VATS provides for excellent exposure of additional levels with the advantages of less operative time and blood loss per operated level.

Anterior Single Rod Instrumentation for Thoracolumbar Adolescent Idiopathic Scoliosis With And Without the Use of Structural Interbody Support

A radiographic and clinical outcomes analysis of 41 patients treated for thoracolumbar adolescent idiopathic scoliosis utilizing a single anterior rigid rod construct. To evaluate the necessity of structural interbody support to improve primary curve correction and preserve or augment lordosis when used in conjunction with a single anterior rigid rod construct, to identify parameters that predict horizontalization of the lowest instrumented vertebra, adjacent disc angulation, and distal uninstrumented vertebrae, and to assess patient satisfaction following surgery. Instrumentation-induced kyphosis has been a concern with nonrigid anterior systems used in the past for the treatment of scoliosis. Interbody structural support has been recommended to maintain appropriate sagittal profile when anterior systems are utilized. It has also been suggested that the use of structural interbody support creates a fulcrum to increase curve correction when compression is applied to the convexity of the deformity. However, the necessity of interbody structural support when used in conjunction with a rigid anterior system has not been previously evaluated in patients with adolescent idiopathic scoliosis. Forty-one patients mean age 15.9 years (range 12.1-18.6 years) with thoracolumbar adolescent idiopathic scoliosis underwent anterior spinal fusion using a single 6.0 to 6.5 mm solid rod construct between June 1995 and August 1999 performed by the senior author (T.G.L.). Four additional patients with thoracolumbar curves with similar anterior instrumentation over the same time period were lost to follow-up or had incomplete records and were not included in the study. Structural interbody support was used in 21 patients and packed morselized autograft alone was used in 20 patients. The patients in the group with packed morselized bone alone generally underwent surgery earlier in the series before the author began using structural interbody support on a regular basis. Each patient had a minimum follow-up of 3 years. Preoperative, initial, and most recent (>3 years) follow-up radiographs were reviewed to determine in each group Cobb angle measurements, flexibility of primary, secondary, and fractional curves, apical and end vertebral translation, lowest instrumented vertebral and caudal disc angulation, global coronal and sagittal balance, and sagittal Cobb measurements in both instrumented levels as well as lumbar lordosis (T12-S1). In addition, the SRS outcomes instrument was completed by 38 of 41 patients. The mean preoperative primary curve in patients with structural support was 47 degrees (Group II) and 45 degrees in patients without structural support (Group I). Mean curve correction was to 13 degrees in Groups I and II. One patient in Group II became slightly more unbalanced at final follow-up; otherwise all were improved after surgery. Sagittal measurements over instrumented segments as well as total lumbar lordosis (T12-S1) was maintained between preoperative and final postoperative values in both groups. Similarly, in both groups, when horizontalization of the distal end instrumented vertebra was achieved on the preoperative reverse side-bending radiograph, more normal relationships were achieved between instrumented and distal noninstrumented segments (adjacent disc angulation and fractional lumbar curve) at final follow-up (P <or= 0.01). Patients in both groups were equally pleased with their clinical outcomes based on the SRS outcomes instrument. The use of interbody structural support does not appear to be necessary to maintain an appropriate sagittal profile or to maximize coronal curve correction when a rigid rod construct with packed morselized bone is used for the treatment of thoracolumbar adolescent idiopathic scoliosis. Parameters predicting horizontalization of the lower instrumented vertebra and uninstrumented segments below the construct were identified, which, if achieved, should predict an optimal long-term outcome. Clinical outcomes were very good in both groups.

Friday, November 1, 2001 3:45– 4:28 pm Concurrent Session 3A: Deformity Techniques: 3:45 Selective anterior fusion and instrumentation for the treatment of neuromuscular scoliosis

Purpose of study: Neuromuscular spinal deformity has been traditionally managed using posterior fusion and instrumentation techniques extending to the sacropelvis. This study examines the use of selective anterior fusion/instrumentation in the treatment of certain neuromuscular spinal deformity.Methods used: A retrospective clinical and radiographic review of over 700 children with neuromuscular spinal deformity was completed. Inclusion of 27 patients (mean age, 10.3 years, range, 1 to 18 years) treated with selective anterior fusion/instrumentation technique. Surgical indications included a flexible primary curve, pelvic obliquity and acceptable sagittal balance. Mean follow-up was 5 years (range, 2 to 10 years), with a minimum follow-up of 2 years. The most common diagnoses were myelomeningocele (13 patients) and spinal cord injury (4 patients). Anterior spinal fusion/instrumentation was performed over an average of five levels (range, 3 to 10). Rib autograft and structural allograft were used for fusion. Moss-Miami instrumentation was used in the majority of cases.of findings: Primary curve correction of 70% was achieved (preoperative mean was 60.4 degrees; range, 30 to 108 degrees; postoperative mean was 18.3 degrees; range, 0 to 70 degrees). At final follow-up the mean primary curve was 24.1 degrees (range, 0 to 90 degrees). Pelvic obliquity (preoperative mean was 15.1 degrees; range, 0 to 50 degrees), was significantly reduced (postoperative mean was 3.7 degrees; range, 0 to 15 degrees). One patient experienced significant curve progression resulting from pseudarthrosis and loss of fixation at the proximal end of the construct. Another developed progressive thoracic kyphosis proximal to the instrumented segment requiring proximal extension of fusion 6 years after the initial procedure. A third patient required extension of the anterior fusion because of progression below the fused segment. There was no change in the coronal or sagittal alignment of the fused segments at final follow-up.Relationship between findings and existing knowledge: Neuromuscular spinal deformity has been traditionally managed using posterior fusion and instrumentation techniques extending to the sacropelvis. Little literature exists on the use of anterior spinal fusion and instrumentation alone in neuromuscular spinal deformity.Overall significance of findings: Selective anterior fusion/instrumentation is a viable treatment option in the management of certain neuromuscular deformities. It allows for greater primary curve correction with maintenance of mobile lumbar motion segments, as well as excellent correction of pelvic obliquity.Disclosures: No disclosures.Conflict of interest: No conflicts.

Short-segment bone-on-bone fusion of adolescent idiopathic scoliosis using Kaneda Anterior Spinal System

Purpose of study: The objective of this study was to evaluate a new technique for treatment of idiopathic scoliosis with a single major curve using the short-segment, bone-on-bone approach and the Kaneda Anterior Spinal System (KASS). This report describes the technique and presents the results for our first 10 patients.Methods used: The short-segment bone-on-bone KASS technique was performed in 10 consecutive patients with adolescent idiopathic thoracic or thoracolumbar scoliosis. The mean age was 14.4 years (12 to 20 years), and the average follow-up was 44 months (range, 34 to 61 months). None were lost to follow-up.of findings: Preoperatively, the major curve averaged 48 degrees (38 to 55 degrees); this corrected to 11 degrees (0 to 20 degrees) postoperatively (77% correction rate). Preoperative compensatory curves measured 34 degrees (29 to 39 degrees); these spontaneously corrected to 13 degrees postoperatively (62% correction rate) as a consequence of correction of primary curve. The preoperative tilt angle was 20 degrees (14 to 28 degrees). Postoperatively the tilt angle was reduced to 6 degrees (2 to 10 degrees). The tilt angle correction was 70%. The fusion was healed and postoperative immobilization discontinued 6 to 10 weeks after the procedure. There was no loss of correction. The average number of vertebra fused using our technique was five (four discs). The average number of posterior fusion levels are proposed by King was 10. There were no implant problems, nonunions or serious peri- or postoperative complications.Relationship between findings and existing knowledge: The bone-on-bone short-segment technique permits correction of single-curve idiopathic scoliosis below 75 degrees over half the levels that have been traditionally operated on by posterior instrumentation, yet provides 77% average correction with no nonunion, no loss of correction and healing in 6 to 8 weeks.Overall significance of findings: The new short-segment, bone-on-bone approach for single major curves using the KASS instrumentation provides excellent correction over half the levels operated on by previous posterior systems with rapid fusion and with no loss of correction.Disclosures: Device or drug: Kaneda Anterior Spinal System. Status: approved.Conflict of interest: Robert Gaines, consultant speaker's bureau; and, other support from De Puy Acromed.