Cranial Curve Research Articles

Posterior hemivertebra resection and short-segment fusion with lateral mass screws in congenital scoliosis: a novel strategy for the resource-limited setting

BackgroundPosterior hemivertebra resection and short-segment fusion with pedicle screws are an established treatment in congenital scoliosis, which require pediatric-specific instrumentation. The purpose of this study was to report the results of utilizing cervical lateral mass screws instead of pedicle screws in the treatment of congenital scoliosis in children younger than 5 years old.MethodsIn an IRB-approved retrospective chart review study, patients <5 years old with congenital scoliosis who underwent posterior hemivertebra resection and fusion with lateral mass screws from 2013 to 2017 were included. Demographic information, pre- and post-operative radiographs, complications, and outcomes were extracted from the charts.ResultsTwenty-three patients were included in the final analysis with a mean age of 40 months, of which 14 were female. Patients were followed for a mean of 51.3±13.2 months. The mean blood loss was 210ml, and patients were hospitalized for a mean of 4 days post-operatively. The correction rate of the main coronal curve, compensatory cranial curve, compensatory caudal curve, and segmental sagittal curve was 74.8%, 68%, 65.2%, and 68.9%, respectively. Three complications were observed: one intra-operative pedicle fracture, one case of implant failure, and one deep surgical-site infection, all of which were successfully managed.ConclusionsOur findings suggest that adult lateral mass screws can be used for transpedicular fixation of the thoracic and lumbar vertebrae in low-resource settings where pediatric-specific pedicle instruments are not readily available. The correction rate, outcomes, and complications are similar and comparable to pediatric-specific pedicle screws, in addition to being low-profile and less bulky compared to adult implants.

Long-term results after the one-stage posterior-only surgical correction of thoraco-lumbar kyphoscoliosis in congenital spine deformity caused by two ipsilateral hemi-vertebrae

BackgroundTwo ipsilateral hemivertebrae is less common and presents severe growth imbalance caused by the vertebral anomalies. However, there is a paucity of reports regarding to two ipsilateral thoracolumbar hemivertebrae. The purpose of present study is to evaluate the long-term outcomes of the posterior surgical correction of thoraco-lumbar spine deformity caused by two ipsilateral hemivertebrae.MethodsFrom 2006 to 2014, a total of 14 consecutive pediatric patients with congenital thoraco-lumbar hemivertebrae were treated by posterior excision of hemivertebrae with short segment fusion. The following parameters were measured: coronal major curvature, cranial and caudal compensatory curvature, segmental kyphosis, lumbar lordosis, trunk shift, apical vertebra translation and sagittal vertical axis. These results were compared and evaluated in preoperatively, immediately postoperatively and at the final follow-up. All patients had a minimum of 5 years follow-up.ResultsThe mean age at surgery was 11.1 ± 4.8 years (2yos to 17yos). The mean follow-up period was 80.2 ± 19.4 months (60mons to 117mons). There was a mean improvement of 74.2% in the coronal major curve from a mean angle of 64.1° before surgery to 15.8° at the final follow-up. The cranial and caudal curves improved of 69.8 and 69.0% from 25.6° to 7.7°, 26.9 to 8.2, respectively. The mean thoraco-lumbar kyphosis was 59.9° before and 13.6° after surgery, 20.8° at the final follow-up. Alignment in the coronal and sagittal plane was either maintained or improved within normal values in all patients.ConclusionsGood correction and spinal balance can be achieved by posterior-only hemivertebrectomy in patients with thoracolumbar kyphocsoliosis caused by two ipsilateral hemivertebra. The complication of neurological injury is low but a technically demanding procedure. More attention should be paid in residual curve progression after surgery.

Posterior thoracolumbar hemivertebra resection and short-segment fusion in congenital scoliosis: surgical outcomes and complications with more than 5-year follow-up

BackgroundTreatment of congenital hemivertebra is challenging and data on long-term follow-up (≥ 5 years) are lacking. This study evaluated the surgical outcomes of posterior thoracolumbar hemivertebra resection and short-segment fusion with pedicle screw fixation for treatment of congenital scoliosis with over 5-year follow-up.MethodsThis study evaluated 27 consecutive patients with congenital scoliosis who underwent posterior thoracolumbar hemivertebra resection and short-segment fusion from January 2007 to January 2015. Segmental scoliosis, total main scoliosis, compensatory cranial curve, compensatory caudal curve, trunk shift, shoulder balance, segmental kyphosis, and sagittal balance were measured on radiographs. Radiographic outcomes and all intraoperative and postoperative complications were recorded.ResultsThe segmental main curve was 40.35° preoperatively, 11.94° postoperatively, and 13.24° at final follow-up, with an average correction of 65.9%. The total main curve was 43.39° preoperatively, 14.13° postoperatively, and 16.06° at final follow-up, with an average correction of 60.2%. The caudal and cranial compensatory curves were corrected from 15.78° and 13.21° to 3.57° and 6.83° postoperatively and 4.38° and 7.65° at final follow-up, with an average correction of 69.2% and 30.3%, respectively. The segmental kyphosis was corrected from 34.30° to 15.88° postoperatively and 15.12° at final follow-up, with an average correction of 61.9%. A significant correction (p < 0.001) in segmental scoliosis, total main curve, caudal compensatory curves and segmental kyphosis was observed from preoperative to the final follow-up. The correction in the compensatory cranial curve was significant between preoperative and postoperative and 2-year follow-up (p < 0.001), but a statistically significant difference was not observed between the preoperative and final follow-up (p > 0.001). There were two implant migrations, two postoperative curve progressions, five cases of proximal junctional kyphosis, and four cases of adding-on phenomena.ConclusionPosterior thoracolumbar hemivertebra resection after short-segment fusion with pedicle screw fixation in congenital scoliosis is a safe and effective method for treatment and can achieve rigid fixation and deformity correction.

Posterior vertebral column resection with short-segment fusion for the patients with congenital kyphoscoliosis.

The purpose of this study was to assess the surgical outcomes of posterior vertebral column resection (PVCR) with short-segment fusion for pediatric patients with congenital kyphoscoliosis (CKS). The medical records of 12 consecutive pediatric patients with CKS due to hemivertebrae located in thoracolumbar and lumbar area that had undergone PVCR and presented for follow-up at a minimum of 2 years were retrospectively reviewed. The mean follow-up period was 56.2 months, and the mean age at the surgery was 9.2 years. We evaluated radiographic parameters using plain radiographs, and evaluated segmental correction using computed tomography imaging. The mean values of the preoperative Cobb angle (cranial curve, main curve, and caudal curve) were 16.0°, 41.3°, and 25.0°, respectively. The main curve was reduced 5.4° after surgery and was maintained at 6.3° at the time of the most recent follow-up. The overall correction rate of main curve was 86.6%. Spontaneous correction rate in the cranial curve and caudal curve were calculated as 55.9 and 80.8%, respectively. The mean segmental scoliosis in the osteotomized segments and fused segments at preoperative/postoperative/final follow-up (FFU) were 40.8°/7.8°/9.2° and 34.3°/3.9°/5.1°, respectively. The mean segmental kyphosis in the osteotomized segments and fused segments at the preoperative/postoperative/FFU were 36.0°/3.8°/4.0° and 27.5°/-1.3°/0.7°, respectively. Our data indicate that PVCR with short-segment fusion for CKS can provide good correction in the main curve and spontaneous correction in the compensatory curves after a minimum 2-year follow-up. Further investigation over the long term is mandatory for pediatric patients.

Correlation between Age and Surgical Approach for Thoracic and Lumbar Hemivertebra

Abstract Objective Hemivertebra (HV) is a congenital defect of the formation of the spinal vertebra, which can result in scoliosis or kyphosis along with the related symptomatology of spine deformity. More often than not, it is linked to other abnormalities and requires attention. Its management is surgical and it is of great importance for the physician to choose the right approach at the right time, due to its deteriorative prognosis. Methods Due to the interest of the subject, the authors investigated the world literature between 1990 and 2018 and found 45 articles, reporting thoracic, thoracolumbar, and lumbar HV in children and its postsurgical outcome, aiming to show whether the approaches are equal in terms of the final outcome. Results The chosen surgical method depends much on the level of the pathology. Despite this fact, after analyzing the included data, we found that the surgical techniques are unequal with regard to the purpose of achieving improvement. Age, caudal and cranial curves, segmental kyphosis, and scoliosis are factors playing a major role in this. Conclusion If not treated, HV leads to deterioration and dysfunction. The most optimal result, however, is achieved only when the surgical approach is applied according to age and rest of the accompanying factors, which should be considered in future management planning.

Short fixation with a 3-rod technique for posterior hemivertebra resection in children younger than 5 years old.

ABSTRACTImportanceCongenital hemivertebra is commonly treated with posterior hemivertebra resection with bilateral transpedicular fixation. However, implant‐related complications are common in children younger than 5 years old who undergo this surgical procedure.ObjectiveTo present the preliminary clinical and radiological outcomes of children younger than 5 years old treated by posterior hemivertebra resection and 3‐rod fixation technique.MethodsFrom January 2016 to December 2017, 14 consecutive patients of congenital scoliosis with 16 hemivertebrae were retrospectively reviewed, including 5 girls and 9 boys, aged between 25 and 55 months old (average, 37.6 months). All patients underwent posterior hemivertebra resection with short fixation with bilateral pedicle screws and a convex lamina hook. Surgical complications and corrective outcomes were assessed based on the clinical charts and spinal radiographs with a minimum 24‐month follow‐up.ResultsThe mean Cobb angle of the main curve was 38.4° before surgery, 8.5° after surgery, and 8.7° at final follow‐up. In the compensatory cranial curve, the preoperative Cobb angle of 16.8° was corrected to 8.1° postoperatively and was 10.3° at final follow‐up. In the compensatory caudal curve, the preoperative Cobb angle of 15.9° improved to 5.3° postoperatively and was 7.8° at final follow‐up. The segmental kyphosis was corrected from 13.5° to 0.5° and was 1.1° at final follow‐up. There were no crankshaft phenomena, no proximal kyphosis, and no complications related to the instrumentation.InterpretationPosterior hemivertebra resection with instrumentation with bilateral pedicle screws and a convex lamina hook can achieve rigid fixation and deformity correction.

P90. The surgical strategy of treatment lumbosacral hemivertebra: comparative analysis of under 10 years old and older than 10 years old groups with five years follow up

BACKGROUND CONTEXT The lumbosacral hemivertebra usually leads to the early rapid progress of spinal deformity, shift and large compensatory curve. Compensatory curve of lumbosacral deformities in the early stage of less than 10 years old is often more flexible, while the compensatory curve in children older than 10 usually turns into a structural curve and surgical treatment of deformity in different age is not entirely the same. However, the timing and strategy of lumbosacral hemivertebral surgery in different ages are still controversial. PURPOSE To analyze and compare the surgical strategies and long-term outcomes of lumbosacral hemivertebra deformities in different age groups. STUDY DESIGN/SETTING A retrospective study. PATIENT SAMPLE Eighteen patients with lumbosacral hemivertebra deformity were retrospectively reviewed between 2004 and 2013. OUTCOME MEASURES Clinical and imaging data were collected for statistical analysis. METHODS Patients received a minimum 5-year follow-up and assigned into two groups: Group A (N=8, mean age 6.6 years old) patients who were under 10 years old and underwent hemivertebral resection and short segment fixation, Group B (N=10, mean age 14.3 years old) patients who were older than 10 years old and underwent hemivertebral resection, long segment fixation including compensatory curve. RESULTS Mean follow-up was 6.2 years. In group B all patients were treated with long segment and iliac screw fixation while no iliac screw fixation in group A. The Cobb angle of coronal main curve in group A improved from 31.3° to 9.3° post-op, and to 9.5° at final follow-up. The Cobb angle of coronal main curve in group B improved from 51.5° to 15.5°post-op, and to 16.3°at final follow-up.The Cobb angle of compensatory cranial curve in group A was 23.5° before operation, 13.7°after operation, 16.2° at final follow-up, while in group B 40.5° before operation, 13.3° after operation, 13.8° at final follow-up. CSVL in group A improved from 1.5cm before operation to 0.7 cm at final follow-up and in group B improved from 2.1 cm to 0.9 cm. Fixed fusion segments were 2.1 in group A and 5.6 in group B. The mean operative time and blood loss in Group A was 189 minutes and 380 ml, respectively, and in group B 265 minutes and 750 ml, respectively. The mean operative time and blood loss in group B were statistically significant more than group A. CONCLUSIONS Lumbosacral hemivertebra deformity under 10 years old with flexible compensatory curve undergo short-segment fixation can achieve satisfactory correction, long term maintenance. While older than 10 years old with structural compensatory curve requires long segmental and iliac bone fixation in order to achieve trunk balance and deformity correction and more operative time, blood loss and complications. Early surgical treatment is recommended for lumbosacral hemivertebral deformity. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Midterm Results of Hemivertebrae Resection and Transpedicular Short Fusion in Patients Younger Than 5 Years: How Do Thoracolumbar and Lumbosacral Curves Compare?

Study DesignRetrospective case series with comparative analysis. ObjectiveTo analyze a consecutive cohort of very young patients operated for congenital scoliosis secondary to a single hemivertebra (HV) and compare thoracolumbar (TL) versus lumbosacral (LS) curve results. Summary of Background DataDespite the published successful results regarding early hemivertebra resection and short fusion for congenital hemivertebrae, literature lacks midterm results, especially in very young children. MethodsPatients under 5 years of age, operated by HV resection and transpedicular short fusion, with follow-up longer than 5 years, were included. Preoperative, postoperative (1-year), final radiographic parameters, and complications were recorded. Midterm results were analyzed and TL versus LS curves were compared. ResultsTwenty-three patients were included (14 TL and 9 LS HV). The mean age was 3.5 ± 1.7 years and the mean follow-up was 7.6 years (4.7–13.7). The mean preoperative Cobb angle (40.3° ± 6.7°), corrected 65% postoperatively and 50% at final follow-up. The compensatory cranial curve improved spontaneously from 25.3° ± 14.8° to 13.5° ± 12° and finally to 19.9° ± 10.7°. Preoperative coronal balance corrected postoperatively but worsened at the final follow-up. TL curves corrected more initially than LS curves (TL: −29°, 68%, vs. LS: −22°, 59%; p = .043); however, both groups lost correction at the final follow-up (TL: 4°, 56%, vs. LS: 7°, 39%; p = .186). The LS group had a larger preoperative compensatory curve, which corrected with surgery but lost more correction at the final follow-up (p = .046). Segmental kyphosis was especially corrected in the TL group (TL: −14° vs. LS: −2°, p = .018) and was maintained over time. ConclusionEarly hemivertebra resection and transpedicular short fusion allowed good coronal correction initially, which was difficult to maintain at midterm, especially at the LS junction. Sagittal plane correction was excellent in TL deformities and was maintained over time. Results were more challenging in the LS group compared with TL deformities. Guidance to avoid unwanted results is proposed. Level of EvidenceLevel III.

O 041 - Long-term outcome after hamstring lengthening in children with CP depends on preoperative hamstring length and velocity

Retrospective case series with comparative analysis.To analyze a consecutive cohort of very young patients operated for congenital scoliosis secondary to a single hemivertebra (HV) and compare thoracolumbar (TL) versus lumbosacral (LS) curve results.Despite the published successful results regarding early hemivertebra resection and short fusion for congenital hemivertebrae, literature lacks midterm results, especially in very young children.Patients under 5 years of age, operated by HV resection and transpedicular short fusion, with follow-up longer than 5 years, were included. Preoperative, postoperative (1-year), final radiographic parameters, and complications were recorded. Midterm results were analyzed and TL versus LS curves were compared.Twenty-three patients were included (14 TL and 9 LS HV). The mean age was 3.5 ± 1.7 years and the mean follow-up was 7.6 years (4.7–13.7). The mean preoperative Cobb angle (40.3° ± 6.7°), corrected 65% postoperatively and 50% at final follow-up. The compensatory cranial curve improved spontaneously from 25.3° ± 14.8° to 13.5° ± 12° and finally to 19.9° ± 10.7°. Preoperative coronal balance corrected postoperatively but worsened at the final follow-up. TL curves corrected more initially than LS curves (TL: −29°, 68%, vs. LS: −22°, 59%; p = .043); however, both groups lost correction at the final follow-up (TL: 4°, 56%, vs. LS: 7°, 39%; p = .186). The LS group had a larger preoperative compensatory curve, which corrected with surgery but lost more correction at the final follow-up (p = .046). Segmental kyphosis was especially corrected in the TL group (TL: −14° vs. LS: −2°, p = .018) and was maintained over time.Early hemivertebra resection and transpedicular short fusion allowed good coronal correction initially, which was difficult to maintain at midterm, especially at the LS junction. Sagittal plane correction was excellent in TL deformities and was maintained over time. Results were more challenging in the LS group compared with TL deformities. Guidance to avoid unwanted results is proposed.Level III.

Efficacy and safety of one-stage posterior hemivertebral resection for unbalanced multiple hemivertebrae: A more than 2-year follow-up

ObjectiveOne-stage posterior hemivertebral resection has been proven to be an effective, reliable surgical option for treating congenital scoliosis due to a single hemivertebra. To date, however, no studies of treating unbalanced multiple hemivertebrae have appeared. This study evaluated the efficacy and safety of one-stage posterior hemivertebral resection for unbalanced multiple hemivertebrae. Patients and methodsAltogether, we studied 15 patients with unbalanced multiple hemivertebrae who had undergone hemivertebral resection using the one-stage posterior approach with at least 2 years of follow-up. Clinical outcomes were assessed radiographically and with the Scoliosis Research Society-22 (SRS-22) score. Related complications were also recorded. ResultsThe mean Cobb angle of the main curve was 62.4° (46°–98°) before surgery and 18.2° (9°–33°) at the most recent follow-up (average correction 73.3%). The compensatory cranial curve was corrected from 28.5° (11°–52°) to 9.1° (0°–30°) (average correction 70.0%). The compensatory caudal curve was corrected from 31.6° (14°–54°) to 6.9°(0°–19°) (average correction 79.1%). The segmental kyphosis/lordosis was corrected from 41.1° (−40° to 98°) to 12.3° (−25° to 41°) (average correction 65.5%). The mean growth rate of the T1-S1 length in immature patients was 9.8mm/year during the follow-up period. Health-related quality of life (SRS-22 score) had significantly improved. Complications include one wound infection and one developing deformity. ConclusionOne-stage posterior hemivertebral resection for unbalanced multiple hemivertebrae provides good radiographic and clinical outcomes with no severe complications when performed by an experienced surgeon. Longer follow-up to detect late complications is obligatory.

Radiologic comparison of posterior release, internal distraction, final PSO and spinal fusion with one-stage posterior vertebral column resection for multi-level severe congenital scoliosis

BackgroundTo compare radiologic results of posterior release, internal distraction, and final pedicle subtraction osteotomy (PSO) and spinal fusionwith one-stage posterior vertebral column resection (PVCR) in treating multi-level severe congenital scoliosis.MethodsForty-onesevere congenital scoliosis patients were used in the study. Group A comprised 24 patients who underwent one-stage PVCR. Group B comprised 17 patients who underwent posterior release with internal distraction, followed by final posterior fusion and instrumentation. The average preoperative main curve was 110.4° (95–130°) in group A and 109.4° (range 90°–126°) in group B. Postoperative follow-up time was ≥2 years (2.0–4.5 years) to analyze the radiographic and clinical outcomes.ResultsA comparison of posterior release, internal distraction, and final spinal fusion with PVCR showed no significant differences in postoperative main curve and compensatory caudal curve correction, coronal and sagittal imbalance. However, significant differences were found between the 2 groups in compensatory cranial curve correction.ConclusionsPosterior release, internal distraction, and final spinal fusion produce better corrective results in compensatory cranial curve correction than PVCR in treating severe multi-level congenital scoliosis.

Congenital scoliosis treated with posterior vertebral column resection in patients younger than 18 years: longer than 10-year follow-up.

OBJECTIVE There have been no reports on the long-term radiographic outcomes of posterior vertebral column resection (PVCR) in patients with congenital scoliosis. The purpose of this study was to evaluate the surgical outcomes and complications after PVCR and its long-term effects on correcting this deformity in children with congenital scoliosis. METHODS The authors retrospectively analyzed the medical records of 45 patients with congenital scoliosis who were younger than 18 years at the time of surgery and who underwent PVCR and fusion with pedicle screw fixation (PSF). The mean age of the patients at the time of surgery was 11.3 years (range 2.4-18.0 years), and the mean length of follow-up was 12.8 years (range 10.1-18.2 years). RESULTS The mean Cobb angle of the main curve was 46.5° before PVCR, 13.7° immediately after PVCR, and 17.6° at the last follow-up. For the compensatory cranial curve, PVCR corrected the preoperative Cobb angle of 21.2° to 9.1° postoperatively and maintained it at 10.9° at the last follow-up. For the compensatory caudal curve, the preoperative Cobb angle of 23.8° improved to 7.7° postoperatively and was 9.8° at the last follow-up. The authors noted 22 complications, and the overall incidence of complications was 48.9%. CONCLUSIONS Posterior vertebral column resection is an effective procedure for managing congenital scoliosis in patients younger than 18 years. Use of PVCR and fusion with PSF for congenital scoliosis achieved rigid fixation and satisfactory deformity correction that was maintained over the long term. However, the authors note that PVCR is a technically demanding procedure and entails risks for major complications and excessive blood loss.

Posterior hemivertebra resection and short segment fusion with pedicle screw fixation for congenital scoliosis in children younger than 10 years: greater than 7-year follow-up.

A retrospective study. To evaluate the surgical outcomes of posterior hemivertebra resection and short segment fusion with segmental pedicle screw fixation in congenital scoliosis in children younger than 10 years. This is the first long-term follow-up on surgical outcomes of posterior hemivertebra resection and short segment fusion using segmental pedicle screw fixation in children younger than 10 years with congenital scoliosis. Patients with congenital scoliosis (n = 18) younger than 10 years at the time of the surgery were treated by posterior hemivertebra resection and bilateral pedicle screw fixation. The mean age at the time of surgery was 6.6 years (range, 2.6-9.8 yr). They were retrospectively studied with a mean follow-up of 11.4 years (range, 7.1-17.3 yr). The mean Cobb angle of the main curve was 34.4° before surgery, 8.6° after surgery, and 12.9° at last follow-up. In the compensatory cranial curve, the preoperative Cobb angle of 14.5° was corrected to 5.9° postoperatively and was 8.4° at last follow-up. In the compensatory caudal curve, the preoperative Cobb angle of 17.4° improved to 4° postoperatively and 6.6° at last follow-up. There were no crankshaft phenomena and no clinical and radiographical features suggestive of spinal stenosis during follow-up. There were no major vascular or neurological complications related to the pedicle screws. Posterior hemivertebra resection after pedicle screw fixation in congenital scoliosis is a safe and effective procedure that can achieve rigid fixation and deformity correction and restore spinal balance. This study showed that early posterior hemivertebra resection of congenital scoliosis before structural changes occur above or below can reduce fusion length, prevent curve progression, and effectively achieve a more satisfactory correction without hazardous iatrogenic spinal stenosis, crankshaft phenomena, or neurological complications. 3.

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.

Hemivertebrae resection for unbalanced multiple hemivertebrae: is it worth it?

To assess the correction effect of hemivertebra resection for unbalanced multiple hemivertebrae by measuring corresponding parameters in both coronal and sagittal planes on series posteroanterior and lateral radiographs and report the related complications. Twelve children with unbalanced multiple hemivertebrae were operated on by hemivertebra resection through a combined anterior and posterior approach or a posterior-only procedure. Mean age at time of surgery was 9.8 years (range 2-14 years). They were retrospectively studied with a mean follow-up of 48.7 months (range 30-60 months). The mean Cobb angle of the main curve was 65.3° (range 45°-92°) before surgery and 13.8° (range 4°-30°) at the last follow-up. The correction rate was 80.0% (range 65.5-92.4 %). The compensatory cranial curve was corrected from 25.8° (range 5°-53°) to 11.7° (range 0°-34°) with a correction rate of 65.9% (range 33.3-100%), and the compensatory caudal curve was corrected from 32.4° (range 17°-57°) to 7.1° (range 0°-20°) with a correction rate of 81.4% (range 53.1-100%). The angle of segmental kyphosis was 41.3° (range 12°-76°) before surgery and 17.0° (range -12° to 45°) at the final follow-up. The coronal imbalance was -1.0 cm (range -3.5 to 3 cm) before surgery and 0.0 cm (range -1.0 to 1.5 cm) at the most recent follow-up. The sagittal imbalance was 0.9 cm (range -3.2 to 3 cm) before surgery and 0.6 cm (range -3.0 to 3.5 cm) at the most recent follow-up. Complications including pedicle fractures, and pseudarthrosis were found in two patients (20 %). In the patients with unbalanced multiple hemivertebrae, hemivertebra resection allows for excellent correction in both the coronal and sagittal planes, and great care should be taken to reduce the rate of complications.

Early outcome of one-stage posterior transpedicular hemi-vertebra resection in the treatment of children with congenital scoliosis

To evaluate the early outcomes of children with congenital scoliosis treated by one-stage transpedicular hemi-vertebra resection. From July 2005 to June 2006, 27 consecutive cases of congenital scoliosis managed by one-stage transpedicular hemi-vertebra resection with instrumentation were investigated retrospectively. There were 11 girls and 16 boys, with a mean age of 5.5 years at surgery (range 1.3 - 10.0 years). Location of the hemi-vertebra was in the thoracic spine in 12 cases and in the lumbar spine in 15 cases. Radiographic evaluations were performed on the preoperative, postoperative, and latest follow-up standing posteroanterior and lateral radiographs. The average operation time was 4 hours (range 3-6 hours), and the mean blood loss during operation was 750 ml (range 300 - 2200 ml). The mean fusion level was 2 to 7 segments, average 4.4 segments. The average follow-up period was 16 months (range 12 - 34 months). Mean Cobb angle of the total main curve was 40.0° before surgery, 12.6° after surgery, and 15.2° at latest follow-up. Mean Cobb angle of the segmental main curve was 35.6° before surgery, 11.6° after surgery, and 12.1° at latest follow-up. The trunk shift was improved from 16.5 mm before operation to that of 7.5 mm after the operation and 7.6 mm at the latest follow-up. Compensatory cranial curve improved from 19.4° before surgery to 8.9° after surgery, and compensatory caudal curve improved from 26.3° to 12.8°. The angle of segmental kyphosis was 26.4° before surgery and 14.6° after surgery in cases with thoracic hemivertebrae, and averaged 11.2° before surgery and 3.9° after surgery in cases with lumbar hemivertebrae. Peri-operative complications included two pedicle screws malpositioning and one case with pelvic tilt. There was no neurological complication. One-stage transpedicular hemi-vertebra resection with instrumentation has a good capability of correcting deformity on the frontal and sagittal planes, which is available in children with middle or lower thoracic or lumbar hemivertebrae.

Hemivertebra Resection and Osteotomies in Congenital Spine Deformity

Retrospective study of posterior hemivertebra resection and osteotomies with transpedicular instrumentation in very young children. Assessment of early intervention in congenital scoliosis with almost complete correction of the main deformity. There is a trend to early correction of congenital deformities, however, there is a lack of long-term follow-up. Forty-one children aged 1 to 6 years with congenital scoliosis were operated on by hemivertebra resection by a posterior only approach with transpedicular instrumentation. Mean age at time of surgery was 3 years 5 months. They were retrospectively studied with a mean follow-up of 6 years 2 months. In group 1 (patients without bar formation), the average Cobb angle of the main curve was 36 degrees before surgery and 7 degrees after surgery. Compensatory cranial curve improved spontaneously from 15 degrees to 3 degrees, compensatory caudal curve from 17 degrees to 4 degrees. The angle of kyphosis was 22 degrees before surgery and 8 degrees after surgery. In group 2 (patients with bar formation) the main curve improved from 69 degrees to 23 degrees, cranial curve from 27 degrees to 11 degrees, caudal curve from 34 degrees to 14 degrees, and kyphosis from 24 degrees to 9 degrees. Posterior hemivertebra resection, in case of bar formation with osteotomy of the bar, allows for excellent correction in both the frontal and sagittal planes, with a short segment of fusion. Early surgery in young children prevents the development of severe local deformities and secondary structural curves, thus allowing for normal growth in the unaffected parts of the spine.

Halbwirbel-Resektion bei kongenitaler Skoliose - Frühzeitige Korrektur im Kindesalter

Congenital scoliosis due to hemivertebrae usually progresses during further growth and leads to severe deformities. Early correction in young children is therefore required. Thirty-six hemivertebrae in 33 children aged 1 to 6 years (average 3 years 5 months) underwent surgical intervention. Mean follow-up was 4.5 years (2 months to 13 years). The hemivertebra was resected by a posterior approach. The gap after resection was closed by compression via a transpedicular instrumentation, thus correcting the scoliotic deformity. Mean Cobb angle of the main curve was 45.9 degrees preoperatively, 11.9 degrees postoperatively, and 9.9 degrees at latest follow-up. The compensatory cranial curve improved spontaneously from 18.4 degrees preoperatively to 5.0 degrees postoperatively and 3.7 degrees at latest follow-up. The compensatory caudal curve improved from 21.3 degrees to 6.7 and 5.4 degrees. The angle of kyphosis was 22.8 degrees preoperatively, 8.9 degrees postoperatively, and 6.8 degrees at latest follow-up. There was one infection, 2 pedicle fractures, and 3 implant failures. In 3 patients additional operations were performed due to new developing deformities. Correction surgery of congenital scoliosis should be performed early before the development of severe local deformities and secondary structural changes. Posterior resection of the hemivertebrae with transpedicular instrumentation allows for early intervention in very young children. Excellent correction in both the frontal and sagittal planes, and a short segment of fusion allow for normal growth in the unaffected parts of the spine.

Analysis of cranial 133-Xenon clearance in the newborn infant by the two-compartment model.

Cranial and chest clearance curves after intravenous administration of 133-Xenon was obtained on 112 occasions in 62 newborn infants admitted to our neonatal intensive care unit. The mean postnatal age was 5.1 days. The cranial clearance curves were submitted to two-compartment analysis. The compartmental clearance rate constants were 1.49 +/- 0.61/min and 0.099 +/- 0.033/min respectively while the fractional flow to the fast compartment was 0.51 +/- 0.14. Possible artefacts, particularly relevant to newborns, were analysed by computer simulation. It is concluded that the cranial 133-Xenon clearance curves varied considerably within the group of ill newborns and that the mean two-compartment parameter values differed considerably from those of healthy premature infants or adults, with or without cerebral illness. But the computer simulations demonstrated that the two-compartment parameters had high coefficients of variation and were significantly biased by right-to-left shunting of blood through the foramen ovale, by heterogeneity of the flow to the fastest compartment and by contamination of the cranial clearance curves by 133-Xenon in the airways. The radiation dose was 1.3 mGy to the lungs and 0.2 mGy to other tissues.

Fouad I University, Cairo : Faculty of Science

THE annual reprot, 1946–47, of the faculty of science, Found I University of Cairo, gives a brief description of the research activities, including particulars of papers published and some notes on researches in progress. In the Department of Pure Mathematics work is continuing on the distribution of cranial curves and on mortality tables, while in that of Applied Mathematics work is in progress on the unified field theory, the velocity potential of the fluid motion induced by the motion of a cylinder in an infinite mass of compressible fluid, and the effect of polarization on secondary scattered light. In the Department of Physics the subjects under investigation include electron polarization, viscosity of gases, electron diffraction by liquid films, the measurement of atmospheric turbulence, supersonic diffraction through slits and the viscosity of plastics. In the Department of Zoology the study of some biological and morphological aspects of lamelli-branchs, the fauna of Egypt, the excretion of reptiles, and the embryology of scorpions is continuing, and a study has commenced of the anatomy, histology and physiology of the digestive system of some Egyptian Lacertilia. In the Department of Entomology work continued on some of the Bombyliidse of Egypt, and on the biology and ecology of various dung insects.