Efficacy of perioperative halo-gravity traction for treatment of severe scoliosis (≥100°)

Background

There have been no standardized surgical options for severe scoliotic curvatures ≥100°. Halo-gravity traction is a viable option for surgical treatment of severe scoliosis. The aim of this study was to evaluate the efficacy and safety of perioperative halo-gravity traction for scoliosis curves ≥100° with respect to radiographic outcomes and clinical complications.

Methods

A total of 21 scoliosis patients with ≥100° curves (average 118.7°; range 100°-158°) with a minimum 2-year follow-up (average 41.8 months; range 24.0-97.0 months) who underwent spinal instrumented fusion using perioperative halo-gravity traction were analyzed. Diagnoses were neuromuscular scoliosis (n = 10), idiopathic (n = 9), and congenital (n = 2). In all, 15 patients were treated by the anterior release procedure followed by final posterior fusion and 6 patients by posterior fusion alone. Six patients had only preoperative traction preceding posterior fusion alone, 6 patients only staged traction between anterior release and final posterior fusion, and 9 patients had both preoperative traction preceding anterior release and staged traction preceding final posterior fusion. The average overall traction period in all patients was 67 days (range 10–78 days).

Results

Radiographic outcomes demonstrated 51.3% correction of the major Cobb angle, 40 mm correction of apical vertebral translation, 76 mm increase of T1-S1 length, and 20.7% increase of space available for lungs at the ultimate follow-up (all comparisons P < 0.05). Preoperative traction demonstrated 27.5% correction of the major curve Cobb angle, 51.5 mm increase of T1-S1 length, 14.9% increase of space available for the lungs (all comparisons P < 0.05). Staged traction after anterior release demonstrated 37.2% correction of the major curve Cobb angle, 26.1 mm correction of apical vertebral translation, 56.5 mm increase of T1-S1 length, 14.2% increase of space available for the lungs (all comparisons P < 0.05). There were only two patients with a pin-site problem, and one required débridement. There were no neurological deficits or clinical complications.

Conclusions

Scoliosis patients with ≥100° curves can be managed successfully by corrective fusion surgery concomitant with perioperative halo-gravity traction without significant complications.     

Die Compliance als Prognosefaktor bei der konservativen Behandlung idiopathischer Skoliosen

Background

The purpose of this study was to assess the compliance of brace treatment and the correlation with outcomes in patients with idiopathic scoliosis.

Methods

Ninety adolescent patients completed treatment with the Dresden scoliosis orthosis. After a mean follow-up time of 4.3 years, their level of compliance was retrospectively assessed and correlated with the radiographic results.

Results

The amount of primary correction was 36% in the lumbar spine and 25% in the thoracic spine. Of the patients, 59.4% were compliant (daily duration of brace treatment >20 h). The success rate in this group (improved or constant Cobb angles during therapy) was 89%. With good compliance and primary correction of more than 30%, the average Cobb angle at follow-up had improved by 8.3° in the thoracic spine and by 12.4° in the lumbar spine compared with the initial Cobb angle. Eleven of 39 patients in the noncompliant group but only four of 57 compliant patients underwent surgery.

Conclusion

Compliance with orthosis therapy and the amount of primary correction are together the most important factors for predicting the final outcome of brace treatment in idiopathic scoliosis. Influencing factors on compliance must be further analyzed.     

Our experience and early results with a complementary implant for the correction of major thoracic curves

Purpose

In our article, we would like to introduce a new auxiliary implant called the CAB hook, for use in posterior approach scoliosis surgery.

Methods

Since 2007, we operated 42 patients with the CAB hook with an average preoperative Cobb angle of 59.3° (28°–92°). In three cases, the posterior approach was preceded by ventral release and Halo traction. In four cases, besides the CAB hooks, SCS hooks and pedicular screws, in three cases both CAB and SCS hooks, in nine cases CAB hooks with SCS pedicular screws, and in 23 cases, only CAB were used. The average follow-up time was 21.6 month (2–51).

Results

All the patients are satisfied with the results. No reoperation was needed due to the loss of correction, pain, implant failure, or infection. The average postoperative Cobb angle decreased to 24.7° (4°–60°). Based on this we calculated the Cincinnati Correction Index (CCI), which was 1.53 (0.7–4.8), which means that our correction exceeded the flexibility of the spine based on the lateral bending X-ray by 53 %.

Conclusion

As with all new surgical techniques and implants after the short learning curve, we were able to improve the degree of correction and decrease the time of surgery. One of the advantages of the CAB hook is that besides a few implant-specific instruments, no special instrumentation is required for insertion, and image intensifier need not be used.     

Skip pedicle screw fixation combined with Ponte osteotomy for adolescent idiopathic scoliosis

Purpose

This study aimed to determine whether Ponte osteotomy combined with skip pedicle screw fixation (SPSF) can improve the correction rate and restore thoracic kyphosis for patients with adolescent idiopathic scoliosis.

Methods

Surgical time, blood loss, preoperative Cobb angle of the main thoracic curve, flexibility, Cobb angle at 1 year after surgery, thoracic curve correction rate, and Cincinnati correction index (CCI) were determined for both the Ponte (n = 17) and non-Ponte (control; n = 21) groups. Furthermore, kyphotic angles at T5–T12 before and 1 year after the surgery were measured.

Results

The following measurements were obtained for the Ponte and control groups, respectively: surgical time, 236 ± 13 and 187 ± 9 min; blood loss, 1,141 ± 150 and 745 ± 120 g; preoperative Cobb angle of the main thoracic curve, 52.5° ± 10.4° and 51.5° ± 9.2°; flexibility, 31.7 ± 13.2 and 45.1 ± 12.3 % (p = 0.003); thoracic curve correction rate, 62.0 ± 2.5 and 63.6 ± 2.5 %; CCI, 2.2 ± 0.2 and 1.5 ± 0.1 (p = 0.003); preoperative kyphotic angle at T5–T12, 11.3° ± 11.2° and 13.0° ± 9.0°; and kyphotic angle at T5–T12 at 1 year after the surgery, 21.8° ± 1.7° and 24.2° ± 1.9°.

Conclusion

Ponte osteotomy was combined with SPSF in case of rigid curve. CCI was significantly greater in the Ponte group. Postoperative thoracic kyphotic angles were identical in both groups.     

Management of spinal deformity in cerebral palsy: conservative treatment

Introduction

The incidence of scoliosis in Cerebral Palsy (CP) is directly related to the Gross Motor Function Classification System (GMFCS) level. The natural history of untreated scoliosis in patients with CP is one of progression and factors implicated in deterioration include type of involvement (quadriplegia), poor functional status (nonambulatory, GMFCS levels IV and V), and curve location (thoracolumbar). The generally accepted incidence in the overall CP population is 20–25 %.

Materials and methods

We recently published our short term results for 31 children treated with a short lumbar brace. In cases of a "positive hands up test" we recommend a short lumbar brace, and in patients with scoliosis with a Cobb angle >20° a double shelled brace.

Results

In our study, there was a correction of 37 % for the lumbar Cobb angle and 39 % for the thoracic Cobb angle at a mean follow-up of 28 months.

Conclusion

The incidence of scoliosis in the overall CP population is 20–25 % and is directly related to the GMFCS level. Therefore, we recommend early treatment and prescribe a short lumbar brace in patients with dynamic instability of the trunk, and in scoliosis with a Cobb angle >20° a double shelled brace.     

Hat die Nachtorthese in der Skoliosetherapie noch eine Berechtigung?

Background

The aim of our investigation was to evaluate the effectiveness of isolated night-time treatment in idiopathic scoliosis.

Methods

Twenty-two children (average age 11.9 years; range 5–12 years) underwent treatment with the“Dresdner night-time brace.” We indicated brace treatment in all children with a Cobb angle of 20–25° and also in those with an angle of 15–19° in cases of progression. Over a follow-up period of 25 months, clinical and radiological observations were made.

Results

A primary correction of 82.2% was obtained. The mean Cobb angle in an upright position without orthosis before treatment was 20.2°. At the end of treatment, this angle reached 15.8°. Operations were able to be avoided completely. In only three cases with radiographic progression (development of angles >25°), part-time bracing had to be stopped and changed to full-time bracing. We observed an overall success rate of 86.4% (patients with improved Cobb angles or halted progression).

Conclusion

We were able to show a positive effect of part-time bracing in selected patients with mild scoliosis and a higher risk of progression. The negative medical and psychosocial consequences of 23-h brace treatment can therefore be avoided in certain patients.     

Preoperative short-term traction prior to posterior vertebral column resection: procedure and role

Purpose

Severe rigid spine deformity with sharp curve can be effectively corrected by posterior vertebral column resection (PVCR). Meanwhile, high risk of this procedure also has been recognized generally. The aim of this study is to review and evaluate the role of preoperative skull-femoral traction prior to PVCR for extremely severe rigid spinal deformity with sharp angular curve >150°.

Methods

Twelve cases with extremely severe rigid deformities and sharp curves were treated by skull-femoral traction before operation. For them, the mean preoperative major scoliotic curve and kyphosis were 153° (110°–168°) and 109° (61°–180°). Continuous skull-femoral traction in supine position was started 4 weeks before operation. In the process of traction, tolerance, neurologic status, deformity changes, etc., were reviewed and documented for analysis. PVCR were performed in all these patients for final and main correction.

Results

The final traction force in the 12 cases was 63 % of body weight. After 4-week traction, the main scoliotic curve and kyphosis were decreased by 34 and 31 %. In 1 week, main scoliotic curve and kyphosis were decreased by 19 and 15 %. In 2 weeks, the major scoliosis curve was decreased by 11 %, but kyphosis was unexpectedly increased by 4 %. Deformity in the last 2 weeks was less significant than the first 2 weeks. After PVCR, the main scoliotic curve and kyphosis were improved 69 and 66 %. No permanent neurological damage occurred.

Conclusion

Preoperative skull-femoral traction effectively mitigates the neurological risks of PVCR for extremely severe rigid spinal deformity with sharp curve. During traction, scoliosis can be improved more significantly and easily than kyphosis.

     

Posterior vertebral column resection in early onset spinal deformities

Purpose

Early onset spinal deformities (EOSD) can be life-threatening in very young children. In the growing spine, surgical intervention is often unavoidable and should be carried out as soon as possible. A deformed section of the spine not only affects the development of the remaining healthy spine, but also that of the chest wall (which influences pulmonary function), the extremities and body balance. Posterior vertebral column resection (PVCR) represents an effective surgical solution to address such problems. However, reports in the literature concerning PVCR are mostly limited to its use in adolescents or adults. The purpose of this study was to illustrate our experience with PVCR in EOSD and to describe the surgical technique with respect to the unique anatomy of young children.

Materials and methods

Four children [mean age 3.7 (range 2.5–5.2) years] with severe spinal deformity underwent PVCR through a single approach. Multimodal intraoperative monitoring was used in all cases. Surgery included one stage posterior circumferential resection of one vertebral body along with the adjoining intervertebral discs and removal of all posterior elements. A transpedicular screw-rod system was used for correction and stabilisation. Fusion was strictly limited to the resection site, allowing for later conversion into a growing rod construct at the remaining spine, if necessary. Relevant data were extracted retrospectively from patient charts and long spine radiographs.

Results

The mean operation time was 500 (range 463–541) min, with an estimated blood loss of 762 (range 600–1,050) ml. Mean follow-up time was 6.3 (range 3.5–12.4) years. After PVCR, the mean Cobb angle for scoliosis was reduced from 69° (range 50–99°) to 29° (5–44°) and the sagittal curvature (kyphosis) from 126° (87–151°) to 61° (47–75°). The mean correction of scoliosis was 57 % (18–92°) and of kyphosis, 51 % (44–62°). There were no spinal cord-related complications. In three patients, spinal instrumentation for growth guidance (fusion less growing rod technique) was applied. Two patients had complications: one patient had a complication of anesthesia, halo pin failure, and revision surgery with extension of the instrumentation cranially due to loss of correction; the second patient had a postoperative infection, which required plastic reconstructive measures.

Conclusion

PVCR appears to be an effective technique to treat severe EOSD. There are important differences in its use in young children when compared with older patients. In patients with EOSD, additional surgical procedures are often necessary during growth, and hence non-fusion instrumentation beyond the vertebral resection site is advantageous, as it permits spinal growth and the later addition of fusion.     

Operative Therapie der idiopathischen Skoliose mittels ventraler Doppelstabinstrumentation

Background

In the surgical treatment of idiopathic scoliosis both anterior and posterior correction and instrumentation techniques are available. The aim of the present study was to analyse the results of a new anterior dual rod instrumentation.

Patients and methods

Prospective analysis of radiometric and clinical parameters of 93 patients operated on between 1996 and 2004 using the Münster Anterior Dual Rod System.

Results

The average curve correction was 65% (fusion length usually Cobb levels) with a preoperative Cobb angle of 59°. Postoperative loss of correction amounted to 1.5° (average follow-up of 36 months). Apical vertebral derotation averaged 45% in the thoracic and 53% in the lumbar spine with a subsequent correction of the rib hump of 66% and the lumbar hump of 81%. There were no revisions or neurological complications.

Conclusion

Anterior dual rod instrumentation enables an effective and safe three-dimensional curve correction in single structural curves with only minimal loss of correction.     

Behandlung der jugendlichen idiopathischen Skoliose mittels Korsett

Background

The purpose of this study was to analyze patients with adolescent idiopathic scoliosis (AIS) treated with bracing at The Royal Children’s Hospital in Melbourne Australia according to the Scoliosis Research Society (SRS) criteria and evaluate the effectiveness of this treatment method.

Patients and methods

During the 1 year survey 125 patients with AIS were treated with bracing and 52 (42?%) of those fulfilled the SRS criteria. Measurements were performed according to the follow-up visits at 6 and 12 months.

Results

The mean age of the patients was 13.1 years and the mean Cobb angle at the start of therapy was 31.8°. Thirtynine (76?%) patients were treated successfully and an improvement of the Cobb angle was achieved in 26 (51?%) patients. A further 6 patients (12?%) required surgery and 7 (14?%) showed a Cobb angle of more than 45° after reaching skeletal maturity.

Conclusion

The results show the effectiveness of bracing as a treatment method for patients with AIS. The SRS criteria provide good guidance to classify patients who are likely to benefit from this treatment. A better comparison of the outcome with other studies can be achieved by using these criteria.     

Use of the iPhone for Cobb angle measurement in scoliosis

Purpose

The Cobb technique is the universally accepted method for measuring the severity of spinal deformities. Traditionally, Cobb angles have been measured using protractor and pencil on hardcopy radiographic films. The new generation of mobile ‘smartphones’ make accurate angle measurement possible using an integrated accelerometer, providing a potentially useful clinical tool for assessing Cobb angles. The purpose of this study was to compare Cobb angle measurements performed using a smartphone and traditional protractor in a series of 20 adolescent idiopathic scoliosis patients.

Methods

Seven observers measured major Cobb angles on 20 pre-operative postero-anterior radiographs of Adolescent Idiopathic Scoliosis patients with both a standard protractor and using an Apple iPhone. Five of the observers repeated the measurements at least a week after the original measurements.

Results

The mean absolute difference between pairs of smartphone/protractor measurements was 2.1°, with a small (1°) bias toward lower Cobb angles with the iPhone. 95% confidence intervals for intra-observer variability were ±3.3° for the protractor and ±3.9° for the iPhone. 95% confidence intervals for inter-observer variability were ±8.3° for the iPhone and ±7.1° for the protractor. Both of these confidence intervals were within the range of previously published Cobb measurement studies.

Conclusions

We conclude that the iPhone is an equivalent Cobb measurement tool to the manual protractor, and measurement times are about 15% less. The widespread availability of inclinometer-equipped mobile phones and the ability to store measurements in later versions of the angle measurement software may make these new technologies attractive for clinical measurement applications.     

Preliminary application of a multi-level 3D printing drill guide template for pedicle screw placement in severe and rigid scoliosis

Purpose

Accurate implantation of pedicle screw in spinal deformity correction surgeries is always challenging. We have developed a method of pedicle screw placement in severe and rigid scoliosis with a multi-level 3D printing drill guide template.

Methods

From November 2011 to March 2015, ten patients (4 males and 6 females) with severe and rigid scoliosis (Cobb angle >70° and flexibility <30%)were included. Multi-level template was designed and manufactured according to the part (two or three levels) of the most severe deformity. The drill template was then placed on the corresponding vertebral surface. Then, pedicle screws were carefully inserted along the trajectories. The other screws were placed in free hand. After surgery, the positions of the pedicle screws were evaluated by CT scan and graded for validation.

Results

48 screws were implanted using templates, other 104 screws in free hand, and the accuracies were 93.8 and 78.8%, respectively, with significant difference. The deformity correction ratio was 67.1 and 41.2% in coronal and sagittal plane post-operatively, respectively. The average operation time was 234.0 ± 34.1 min, and average blood loss was 557 ± 67.4 ml.

Conclusions

With the application of multi-level template, the incidence of cortex perforation in severe and rigid scoliosis decreased and this technology is, therefore, potentially applicable in clinical practice.

     

Pelvic tilt and trunk inclination: new predictive factors in curve progression during the Milwaukee bracing for adolescent idiopathic scoliosis

Introduction

Previous studies had shown that sagittal spinal and pelvic morphology may be associated with the development and progression of adolescent idiopathic scoliosis, but the predictive value of initial spinal and pelvic morphology on the curve progression during brace treatment is unknown. The objective of this study was to evaluate the relation between initial spinopelvic morphology and the risk of curve progression of adolescent idiopathic scoliosis with the Milwaukee brace.

Materials and methods

From 2002 to 2007, adolescent idiopathic scoliosis (single thoracic curve with apex at or above T8) was treated with the Milwaukee brace in 60 girls. Initial standing, full-length lateral radiographs were made and seven sagittal radiographic parameters of spinal and pelvic alignment were measured. Patients were followed until skeletal maturity or progression of Cobb angle >45°. The progression of curve was defined as an increase of Cobb angle ≥6° at final follow-up or progression to surgery during brace treatment.

Results

The 45 patients (75.0 %) who had successful control of curve progression were initially significantly more skeletally mature (higher mean Risser sign) than the 15 patients (25.0 %) who had curve progression. The initial mean Cobb angle was similar between the stable and progressed groups. The mean pelvic tilt, T1-spinopelvic inclination and T9-spinopelvic inclination angles were significantly greater in the stable group than in the progressed group and these three angles were independent predictors for curve progression during brace treatment. There were no significant differences between the stable and progressed groups in initial mean pelvic incidence, sacral slope, thoracic kyphosis or lumbar lordosis angles. Pre-bracing pelvic tilt ≤?0.5° was strongly predictive and T1-spinopelvic inclination ≤3.5° was moderately predictive of curve progression during the Milwaukee brace treatment.

Conclusions

Initial pelvic tilt and spinopelvic inclination angles may predict the curve progression and treatment outcome of adolescent idiopathic scoliosis with the Milwaukee brace.     

Radiographic measurement error of the scoliotic curve angle depending on positioning of the patient and the side of scoliotic curve

Background

The Cobb angle measurement is well established for the measurement of coronal deformity aspect of scoliotic curves. The effect of positional differences in relation to the apex side of the scoliosis is not yet fully quantified. While theoretically plausible that positioning error with rotation toward the apex of the scoliosis would decrease the Cobb angle, the relations are not investigated yet and were object of this study.

Materials and methods

Multiple measurements of the Cobb angle were performed, while turning a spine-pelvic cadaveric specimen with a right-sided thoracic scoliosis of 47° (in neutral position) from 45° to ?45° in steps of 5° using biplanar radiography. Statistical methods were applied to find the critical position, in which measurement errors potentially become clinically relevant (Cobb angle deviation >5°).

Results

Turning the specimen to the right (toward the apex of the scoliosis) produced during the first ?15° of rotation, a Cobb angle ranging from 47° to 45°. At ?20°, the Cobb angle was 42°, at ?25° rotation 37° and at ?30° rotation 36°. Above ?30° rotation, the measured Cobb angle decreased to 36° (77 % of the original Cobb angle). No relevant differences were found by rotating the specimen to the left (away from the apex) (47° at neutral rotation and 44° at maximal error rotation of +45°).

Conclusion

The influence of rotational misplacement of the patient at the time of image acquisition on Cobb angle measurements is negligible for a rotational misplacement of ±20° of rotation for a idiopathic right-sided thoracic scoliosis of 47°. Over 20° of rotational misplacement of the patient toward the apex of the scoliosis falsely decreases the Cobb angle.

     

Porcine spine finite element model: a complementary tool to experimental scoliosis fusionless instrumentation

Purpose

Developing fusionless devices to treat pediatric scoliosis necessitates lengthy and expensive animal trials. The objective was to develop and validate a porcine spine numerical model as an alternative platform to assess fusionless devices.

Methods

A parametric finite element model (FEM) of an osseoligamentous porcine spine and rib cage, including the epiphyseal growth plates, was developed. A follower-type load replicated physiological and gravitational loads. Vertebral growth and its modulation were programmed based on the Hueter–Volkmann principle, stipulating growth reduction/promotion due to increased compressive/tensile stresses. Scoliosis induction via a posterior tether and 5-level rib tethering, was simulated over 10 weeks along with its subsequent correction via a contralateral anterior custom tether (20 weeks). Scoliosis induction was also simulated using two experimentally tested compression-based fusionless implants (hemi- and rigid staples) over 12- and 8-weeks growth, respectively. Resulting simulated Cobb and sagittal angles, apical vertebral wedging, and left/right height alterations were compared to reported studies.

Results

Simulated induced Cobb and vertebral wedging were 48.4° and 7.6° and corrected to 21° and 5.4°, respectively, with the contralateral anterior tether. Apical rotation (15.6°) was corrected to 7.4°. With the hemi- and rigid staples, Cobb angle was 11.2° and 11.8°, respectively, with 3.7° and 2.0° vertebral wedging. Sagittal plane was within the published range. Convex/concave-side vertebral height difference was 3.1 mm with the induction posterior tether and reduced to 2.3 with the contralateral anterior tether, with 1.4 and 0.8 for the hemi- and rigid staples.

Conclusions

The FEM represented growth-restraining effects and growth modulation with Cobb and vertebral wedging within 0.6° and 1.9° of experimental animal results, while it was within 5° for the two simulated staples. Ultimately, the model would serve as a time- and cost-effective tool to assess the biomechanics and long-term effect of compression-based fusionless devices prior to animal trials, assisting the transfer towards treating scoliosis in the growing spine.

     

Posterior corrective surgery for moderate to severe focal kyphosis in the thoracolumbar spine: 57 cases with minimum 3 years follow-up

Purpose

To evaluate the radiological and clinical outcomes of the corrective surgery for patients with moderate to severe focal kyphosis in thoracolumbar spine.

Methods

Fifty-seven patients with moderate to severe focal kyphosis of the thoracolumbar spine underwent apical segmental resection osteotomy with dual axial rotation correction at our hospital. There were 30 male and 27 female patients. The mean age was 34.3 years. The kyphosis level radiographs were obtained from each patient before surgery, immediately after surgery and at follow-up. Local kyphosis and scoliosis Cobb angles were measured. Full-spine standing radiographs were obtained before surgery and at follow-up, and the spine sagittal and coronal balance were evaluated. The height of patients, the Frankel grading system for neurological functions, the Oswestry disability index for life quality, the visual analogue score for back pain and the patient satisfactory index for satisfaction to surgery were applied before surgery and at follow-up. The radiological and clinical outcomes were further analyzed in different sub-groups of patients according to etiology, severity of kyphosis, age, level of kyphosis apex, Frankel grade before surgery, and complications.

Results

The average follow-up time of patients was 46.1 months. The average kyphosis angle reduced from 94.6° before surgery to 31.0° immediately after surgery, and remained at 34.4° at follow-up. The sagittal balance of the spine, height of patients, Frankel grading, Oswestry disability index and visual analogue score were improved. The patient satisfactory index (PSI) showed a satisfied rate of 91.2%. The correction rate was significantly higher in patients with kyphosis angle less than 95° and age less than 35 years. The clinical improvement rate was significantly higher in patient with kyphosis apex at lower thoracic spine or thoracolumbar segment, Frankel grade E before surgery and no complication group. The incidence of intra-operative and early stage complications was 38.6%, and the incidence of instrumentation failure was 10.5%. The most severe complication was transient spinal cord injury, and the incidence was 7.0%. All complications got good relief after appropriate intervention.

Conclusions

Apical segmental resection osteotomy with dual axial rotation correction is an effective procedure to treat moderate to severe focal kyphosis, the prevention of serious neurological complications is fundamental to achieve the ideal clinical results.