Cobb Angle Of Lumbar Curve Research Articles

Distal Adding-on Phenomenon in Scoliosis Secondary to Chiari Malformation Type I: Incidence and Risk Factors.

A retrospective study. The aim of this study was to investigate the incidence and risk factors for distal adding-on (AO) phenomenon after posterior spinal fusion (PSF) in scoliosis secondary to Chiari malformation type I (CMS) patients with right major thoracic curve. Distal AO phenomenon is a common complication observed in adolescent idiopathic scoliosis (AIS), which is significantly associated with unsatisfactory outcomes. However, few studies specifically focused on the incidence and risk factors of distal AO in CMS. Seventy-eight CMS adolescents were included with a minimum of 2-year follow-up after PSF. patients with distal AO at the final follow-up were divided into AO group and those without were No-AO group. The coronal and sagittal parameters were evaluated preoperatively, immediately after surgery, and at the last follow-up. Clinical outcome was analyzed using the Chicago Chiari Outcome Scale (CCOS). Distal AO was observed in 18 of 78 patients (23.1%). Compared with No-AO group, patients with distal AO had significantly lower Risser sign (P = 0.001), more flexibility of lumbar curve (P = 0.021), higher incidence of lowest instrumented vertebra-last substantially touched vertebra (LIV-LSTV) ≤0 (P = 0.001), smaller postoperative Cobb angle of lumbar curve (P < 0.001), and greater correction rate of lumbar curve (P = 0.001). Logistic regression analysis revealed that low Risser sign (Grade 1-2, odds ratio [OR] = 5.7, P = 0.029) and LIV-LSTV ≤0 (OR = 6.4, P = 0.019) were independent risk factors for distal AO. There was no significant difference of CCOS scores between two groups at the final follow-up (P > 0.05 for all). The incidence of distal AO was 23.1% in CMS patients after PSF. Patients with low Risser sign and LIV-LSTV ≤0 were high risk factors for distal AO.Level of Evidence: 3.

Precision Treatment of Adult Lumbar Degenerative Scoliosis Complicated by Lumbar Stenosis with the Use of Selective Nerve Root Block

Use of short-segment or long-segment fusion is controversial in treatment of adult lumbar degenerative scoliosis (ALDS). The aim of this study was to explore efficacy and feasibility of precision treatment of ALDS with selective nerve root block. From January 2014 to January 2016, a retrospective study of 23 patients with ALDS treated with precision short-segment surgery with at least 2-year follow-up was performed. Fixation segment was determined by selective nerve root block. Visual analog scale and Oswestry Disability Index (ODI) were evaluated preoperatively and at 2-year follow-up. Radiographic measurements included Cobb angle of lumbar curve, lumbar lordosis, sacrum slope, and pelvic tilt. Radiographic evaluation of fusion integrity was performed based on Bridwell interbody fusion grading system at final follow-up. Mean follow-up time was 25.2 ± 1.4 months. Average lumbar curve was 21.6° ± 7.4° preoperatively and 11.2° ± 6.5° at final follow-up (P < 0.01), with correction rate of 48.1%. Lumbar lordosis changed from-37.1° ± 12.9° to-42.1° ± 10.5° at final follow-up (P < 0.01). Mean visual analog scale back pain scores decreased from 6.0 ± 1.8 preoperatively to 1.5 ± 0.8 at final follow-up (P < 0.01), and mean visual analog scale leg pain scores decreased from 8.1 ± 0.6 preoperatively to 1.3 ± 1.3 at final follow-up (P < 0.01). Oswestry Disability Index score improved from 60.9% ± 15.7% preoperatively to 22.1% ± 11.6% at final follow-up (P<0.01). All patients achieved grade I fusion at final evaluation. One patient (4%) needed further surgical intervention. Precision treatment of ALDS with selective nerve root block can achieve favorable clinical outcomes and good fusion with less surgical injury and low complications. Deformity correction is limited, which requires further study.

Adding-on Phenomenon After Surgery in Lenke Type 1, 2 Adolescent Idiopathic Scoliosis: Is it Predictable?

A retrospective study. The aim of this study was to detect risk factors for Adding-on after posterior correction surgery in patients with Lenke 1 or 2 AIS, and to explore whether Adding-on Index could be used to predict Adding-on effectively. Adding-on phenomenon is a common complication in Lenke 1 or 2 AIS patients after correction surgery. However, whether it can be predicted after surgery remains unknown. Lenke 1 or 2 AIS patients receiving correction surgery in our center from January 2009 to July 2013 were analyzed. Antero-posterior and lateral films were evaluated before surgery, at 2 weeks' and 2 years' follow-up. Patients were divided into 2 groups according to whether Adding-on occurred at the 2 years' follow-up. Risk factors of Adding-on were analyzed, and Adding-on Index was proposed and verified. Sixteen patients (16.3%) suffered from distal Adding-on at 2-year follow-up. Several parameters were found to be significantly different between 2 groups, including Risser's sign, postoperative Cobb angle of main thoracic, postoperative Cobb angle of main thoracic curve at 2-year follow-up, preoperative and postoperative Cobb angle of lumbar curve, postoperative Cobb angle of lumbar curve at 2-year follow-up, LIV-EV, LIV-SV, LIV-CSVL, LAV-CSVL, LAV-LIV, DnfS, and postoperative TJK. No significant differences in SRS-22 scores were observed. Binary logistic regression analysis showed that DnfS and postoperative residual Cobb angle of lumbar curve were primary factors for occurrence of Adding-on. According to the regression equation, Adding-on Index was defined as 4 × DnfS-postoperative lumbar curves Cobb angle. On the basis of ROC curve, if Adding-on Index was more than 12, the occurrence rate of Adding-on was 88%. On the contrary, the rate of no Adding-on phenomenon was 80%. DnfS and posterior Cobb angle of lumbar curve were 2 important factors for Adding-on in Lenke 1, 2 AIS patients. Adding-on Index can be used to predict the occurrence of Adding-on effectively. 4.

Anterior instrumentation (dual screws single rod system) for the surgical treatment of idiopathic scoliosis in the lumbar area: a prospective study on 33 adolescents and young adults, based on a new system of classification

The choice of anterior instrumentation in the treatment of lumbar scoliosis in adolescents and young adults is not a new topic for the authors. The first results achieved using the Dwyer surgical modality were reported by one of the authors followed by the results achieved using Zielke (VDS) instrumentation. Today, new techniques and new instrumentations have been developed that challenge the instrumentation choices. Here we describe how the new system of classification of scoliotic curves we developed has been used as a basis for treating idiopathic scoliosis in lumbar area in adolescents and young adults using an anterior approach. A prospective study was carried out between 1998 and 2010 at two hospital centers on 33 adolescents and young adult with idiopathic lumbar scoliosis involving curves of three kinds, on whom surgical treatment was performed using a single solid rod. Topography of curves: our system of classification includes curves corresponding to the following three type of scoliosis: Type K I: double thoracic and lumbar curves (lumbar predominant) scoliosis (17 cases) mean age 16 years all female patients. Mean Cobb angle of lumbar curve 41°. Mean Cobb angle of thoracic curve 28°. The lumbar curve was left hand convex in 15 cases and right hand convex in 2 cases. Horizontal tilting of L4 mean value 22°. C7 offset mean value 3 cm. Type K IV A: unbalanced thoracolumbar scoliosis (13 cases) mean age 17 years, ten female patients and three male patients. Mean Cobb angle of thoracolumbar curve 39°. The thoracolumbar curve was left hand convex 4 times and right hand convex 9 times. Horizontal tilting of L4 mean value 18°. C 7 offset mean value 2.5 cm. Type K VI A: real lumbar (three cases). Age: 17, 15 and 13 years; all female patients. Cobb angle of the lumbar curve 66°, 29° and 70° (all LH convex). Horizontal tilting of L4: 40°, 20° and 46°. C 7 offset: 7 cm, 1 cm and 4 cm. Surgical instrumentation: We used the EUROS AZUR anterior instrumentation for all the procedures. Cages have been used on five patients at the lower stages. Number of vertebrae instrumented: mean five vertebrae. The patients did not wear postoperative orthosis. Mean duration of procedure: 3 h 50 min. Mean blood loss: 350 cm(3). Type K I scoliosis (17 cases): Mean follow-up: 6 years. Correction of the lumbar curve Cobb angle: the mean angle has been corrected from 41° to 21°. Number of vertebrae instrumented: 4:6 times and 5:11 times. Correction of the upper thoracic curve Cobb angle: mean angle corrected from 28° to 19°. Correction of L4 horizontal tilting: mean residual was 7°. Correction of C 7 offset: mean 0.7 cm. Type K IV A scoliosis (13 cases): mean follow-up: 4 years. Correction of the lumbar curve Cobb angle: the mean angle has been corrected from 39° to 16°. Mean number of instrumented vertebrae: 5 (4:4 times, 5:6 times and 6:3 times.) Correction of L4 horizontal tilting: mean residual 5°. Correction of C 7 offset: mean 0.7 cm. Type K VI A scoliosis (three cases): mean follow-up: 7, 2 and 4 years; Correction of the lumbar curve Cobb angle: the angles have been corrected from 66° to 15°, from 29° to 11° and from 70° to 28°. Number of instrumented vertebrae: 5, 4 and 6. Correction of L4 horizontal tilting: residual tilting of 8°, 7° and 17°. Correction of C 7 offset: 1 cm, 0 cm and 1 cm. There has been no report early or late septic or vascular or neurological complications. Instrumentation failure: there were three cases of screw breakage, all occurred on the lowest implant. Revision surgery was undertaken in both cases, only the last plate needed to be replaced and the rod could be kept without any other modification of the construct. In both cases, fusion has been achieved without any loss of correction. The mean loss of correction of the main curve was 2.5° for the three series. Anterior instrumentation of lumbar idiopathic scoliosis gives highly satisfactory morphological and functional results, since the lumbar musculature is spared and the instrumentation placed at the apex of the curvature has selective effects. Despite our preference and that of other surgeons throughout the world for anterior instrumentation, we are still a minority in comparison with the users of posterior instrumentation. There are several reasons for this reticence, including surgeons' training and ideas about pedicular screw fixation, but the main reason has been the lack of a sufficiently exact system of classification. Previous comparative studies between the anterior and posterior approaches have been biased by the use of an excessively restrictive mode of classification (lumbar/thoracolumbar) of the curves. Real lumbar scoliosis, unbalanced thoracolumbar scoliosis and thoracic and lumbar double curve (lumbar predominant) scoliosis should be properly defined before being compared.

Selective thoracic fusion in adolescent idiopathic scoliosis

OBJECTIVE: To define the criteria of selective thoracic fusion in adolescent idiopathic scoliosis patients. METHODS: By reviewing the roentgenograms of adolescent idiopathic scoliosis patients undergoing selective thoracic fusion, the curve type, Cobb angle, apical rotation and translation, trunk shift, and thoracolumbar kyphosis were measured and analyzed. RESULTS: There were 12 King type II patients (PUMC type: IIb1 9, IIc3 3). The coronal Cobb angle of thoracic curve before and after surgery were 54.0 degrees and 19.0 degrees respectively, and the average correction rate was 62.7%. The coronal Cobb angle of lumbar curve before and after surgery were 34.6 degrees and 12.5 degrees respectively, and the average spontaneous correction rate was 64.7%. At the final follow-up, the coronal Cobb angle of thoracic and lumbar curve was 18.8 degrees and 15.9 degrees respectively. There was no significant change in the coronal Cobb angle, apical vertebral translation and rotation compared with that after surgery. 1 patient had 12 degrees of thoracolumbar kyphosis after surgery, no progression was noted at the final follow-up. There was no trunk decompensation or deterioration of the lumbar curve. In this group, 3.5 levels were saved compared with fusing both the thoracic and lumbar curves. CONCLUSION: Selective thoracic fusion can be safely and effectively performed in patients with a moderate and flexible lumbar curves, which can save more mobile segments to maintain a good coronal and sagittal balance.