Relationship between lumbosacral transitional vertebra and postoperative outcomes of patients with Lenke 5C adolescent idiopathic scoliosis: a minimum 5-year follow-up study.

PURPOSE: To assess the incidence of lumbosacral transitional vertebra (LSTV) in Lenke 5C adolescent idiopathic scoliosis (AIS) and evaluate the relationship between postoperative outcomes and LSTV when the lowest instrumented vertebra (LIV) is fixed at L3. METHODS: The study included 61 patients with Lenke 5C AIS who underwent fusion surgery of L3 as the LIV who were followed-up for a minimum of 5 years. Patients were divided into two groups: LSTV + and LSTV-. Demographic, surgical, and radiographic data, including L4 tilt and thoracolumbar/lumbar (TL/L) Cobb angle, were obtained and analyzed. RESULTS: LSTV was observed in 15 patients (24.5%). The L4 tilt was not significantly different between the two groups preoperatively (P = 0.54); however, it was significantly greater in the LSTV group postoperatively (2 weeks: LSTV + = 11.7 ± 3.1, LSTV - = 8.8 ± 3.2, P = 0.013; 2 years: LSTV + = 11.5 ± 3.5, LSTV - = 7.9 ± 4.1, P = 0.006; 5 years: LSTV + = 9.8 ± 3.1, LSTV - = 7.3 ± 4.5, P= 0.042). The postoperative TL/L curve was greater in the LSTV + group, with significant differences at 2 weeks and 2 years postoperatively (preoperative: LSTV + = 53.5 ± 11.2, LSTV - = 51.7 ± 10.3,P = 0.675; 2 weeks: LSTV + = 16.1 ± 5.0, LSTV- = 12.2 ± 6.6, P = 0.027; 2 years: LSTV + = 21.7 ± 5.9, LSTV - = 17.6 ± 5.9, P = 0.035; 5 years: LSTV + = 18.7 ± 5.8, LSTV - = 17.0 ± 6.1, P = 0.205). CONCLUSION: The prevalence of LSTV in Lenke 5C AIS patients was 24.5%. Lenke 5C AIS patients with LSTV with the LIV at L3 had a significantly greater postoperative L4 tilt than those without LSTV and retained the TL/L curve.

Distal adding-on after surgery in Lenke 5C adolescent idiopathic scoliosis: clinical and radiological outcomes.

BACKGROUND: To evaluate the incidence and risk factors of postoperative distal adding-on in patients with Lenke 5C adolescent idiopathic scoliosis (AIS). More accurate selection criteria for the lower instrumented vertebra (LIV) should be confirmed to prevent distal adding-on. METHODS: Forty-six patients with Lenke 5C AIS who underwent posterior fusion were enrolled in the study. Patients were allocated into adding-on and no adding-on groups. Demographic data, clinical data, and radiographic parameters were recorded and compared. RESULTS: Postoperative distal adding-on occurred in eight patients (17.4%) during follow-up. Demographic data, clinical data, and baseline radiographic parameters of the two groups were not significantly different. The postoperative thoracolumbar (TL) or lumbar (L) Cobb angle, LIV translation, and LIV + 1 translation were higher in the adding-on group than those in the no adding-on group, while the postoperative coronal imbalance of the adding-on group was lower than that of the no adding-on group. The level difference of last barely touched vertebra (LBTV) and last substantial touched vertebra (LSTV) with LIV were higher in the adding-on group than in the no adding-on group. CONCLUSION: Postoperative TL/L curve, postoperative LIV translation, postoperative LIV + 1 translation, and postoperative coronal imbalance were determined as risk factors for postoperative distal adding-on in patients with Lenke 5C AIS. Moreover, LIV selection of LBTV-1 or LSTV-1 may cause a higher risk of postoperative distal adding-on.

Cobb-1 versus cobb-to-cobb anterior fusion for adolescent idiopathic scoliosis Lenke 5C curves: a radiological comparative study.

PURPOSE: Anterior fusion is a well-established procedure for the treatment of Lenke 5C adolescent idiopathic scoliosis (AIS). This retrospective study aimed to assess preoperative and postoperative radiographic differences between the conventional anterior fusion and anterior short fusions (ASF) in Lenke 5C AIS. METHODS: Radiographic data of 42 consecutive cases of Lenke 5C AIS, which were surgically treated through anterior segmental fusion, were analyzed retrospectively. Patients have been divided into two groups: C group (n = 19) treated by the conventional fusion from the proximal end vertebra to the distal end vertebra of the main curve and C-1 group (n = 23) treated by ASF, sparing the lowest end vertebra of the main curve. Cobb angles of main curve, apical vertebra tilt, C7 coronal tilt, lowest instrumented vertebra angle (LIV angle), LIV adjacent level disc angulation (LIVDA), and the first uninstrumented vertebra angle (FUV angle) were measured on anteroposterior radiographs of the entire spine. LIVDA, FUV wedging, and rotation were measured on stretch films. C7 sagittal tilt, lumbar lordosis, thoracic kyphosis, and proximal kyphosis junction were measured on lateral radiographs of the entire spine. Repeated-measures analysis of variance and fisher test were used for the statistical analysis. RESULTS: The preoperative main curve was 39.9 ± 9.1° in the C group vs. (versus) 42.8 ± 11.8° in the C-1 group. At a mean follow-up of 26.2 months (range 10.5-66.3 months), postoperative main curve improved of 75.8 ± 21.2 % (10.4 ± 9.2°, p < 0.001) in the C group and of 52.7 ± 18.7 % (20.1 ± 8.1°, p < 0.001) in the C-1 group. All parameters improved except the LIVDA, which was slightly impaired, especially in the C-1 group with 5.6 ± 4.2° vs. 4.4 ± 2.2° in the C group. On stretch films, FUV rotation was the only parameter to differ; it was graded at 1 ± 0.7 in the C-1 group vs. 0.6 ± 0.5 in the C group (p = 0.04). No disk obliquity just under the future instrumentation and equivalent FUV wedging were found in any of the two groups. CONCLUSIONS: The conventional anterior fusion and ASF give equivalent correction in Lenke 5C AIS, but ASF seems to induce adding-on of the disk below the LIV. FUV rotation on stretch films does not seem to be a predictive factor of postoperative radiological outcome.

Comparison between the lowest instrumented vertebrae L3 with the use of direct vertebrae rotation (DVR) and the lowest instrumented vertebrae L4 for non-DVR in adolescents with idiopathic scoliosis Lenke 5C/6C: when LEV is L4.

OBJECTIVE: As there are no substantial selection criteria for determining the lowest instrumented vertebra (LIV) in adolescent idiopathic scoliosis (AIS) Lenke 5C/6C, thus, many surgeons base their selection on experience. The study aims to compare the selection of the lowest instrumented vertebrae (LIV) lumbar vertebra three (L3) with the use of direct vertebrae rotation (DVR) to the lowest instrumented vertebrae (LIV) lumbar vertebra four (L4) with the use of non-DVR for the correction of adolescent idiopathic scoliosis (AIS) Lenke 5C/6C when the lower end vertebrae (LEV) is at lumbar vertebrae four (L4). METHODS: This prospective study involved 101 patients who were divided into two groups based on different techniques. The patients were prospectively followed up for at least four years. All patients included in the study had a lower end vertebra (LEV) at L4, while patients older than 18 years and patients with prior surgical procedures were excluded. The DVR group consisted of 49 patients, and the non-DVR group included 51 patients. RESULTS: The preoperative mean LIV disc angle was 3.1 ± 3 and 3.1 ± 1, P = 0.097, which corrected to 1.2 ± 0 and 1.1 ± 0 in both groups at 4-year follow-up without statistical significance. The LIVDA and LIVT were statistically insignificant at the preoperative, and there were no significant differences at the follow-up visitation. The DVR group achieved a satisfactory coronal and Cobb's angle correction compared to the NDVR group; however, there were no statistical differences at the follow-up visitations. Both groups achieve a satisfactory correction rate without substantial significance in clinical and radiological outcomes. Furthermore, no post-surgical complications were recorded in either group. CONCLUSIONS: DVR is suitable for selecting L3 as the LIV in AIS Lenke 5C/6C compared to L4 in non-DVR. DVR preserved more segments without substantial complications during the follow-up visitations. Nevertheless, both groups will continue to be followed up to prevent adding-on post-surgical complications.

Posterior-only correction surgery for idiopathic scoliosis Lenke type 5c: differences of strategies and outcomes between adult patients and adolescent patients.

PURPOSE: To compare radiographic parameters, and functional and surgical outcomes between lumbar adolescent idiopathic scoliosis (AIS) and lumbar adult idiopathic scoliosis (AdIS). METHODS: A retrospective study was performed to identify Lenke 5c type AIS and AdIS patients from our scoliosis database who had undergone posterior surgical treatment for scoliosis. Preoperative and postoperative radiographic and clinical outcomes were compared between the two groups. RESULTS: A total of 22 patients were included in AdIS group, and 44 matched patients in AIS group. AdIS group had significantly larger L3 and L4 tilt and translation than AIS group (P < 0.05). AdIS group had larger T10-L2 angle and smaller T5-T12 angle (P < 0.05). AdIS group had higher VAS scores (P < 0.05) and pain domain of SRS-22 scores (P < 0.05) as compared to AIS group. Correlation analysis demonstrated positive relationship between VAS scores and T10-L2 angle (r = 0.492, P < 0.05). AdIS group was fused longer than AIS group (P < 0.05). Cobb angle of TL/L curve was larger and correction ratio was smaller at AdIS group (P < 0.05). AdIS group still had significantly larger L3 and L4 tilt and translation than AIS group (P < 0.05). CT measurements demonstrated larger postoperative vertebral body rotation at apical vertebrae and LIV at AdIS group (P < 0.05). Vertebral correction ratio was smaller at AdIS group (P < 0.05). CONCLUSION: Lenke 5c AdIS patients had greater preoperative and postoperative L3 and L4 tilt and translation, as well as less correction of major curve and vertebral body derotation than AIS patients. However, the incidence of adding-on was similar between the two groups.

Impact of Gensingen brace treatment on Lenke 5 curvatures and chronic low back pain in late adolescent and adult scoliosis patients.

Background: Lenke 5C (lumbar and or thoracolumbar) curve patterns lead to loss of lumbar lordosis which is associated with low back pain in later adulthood. We undertook our study to investigate if brace treatment may have an effect on low back pain and on improving the cosmetic appearance in late adolescents and adults. Objectives: To estimate if conservative treatment may have an effect on pain in single lumbar curvatures in late adolescent and adult patients with Adolescent Idiopathic Scoliosis (AIS) using a Gensingen Brace by Weiss (GBW). Method: We investigated AIS patients with Lenke 5C pattern who wore a GBW prospectively. The inclusion criteria of our study were age over 15 years, Cobb angle greater than 20° before treatment and Risser 4 or 5. A verbal pain rating scale was used (no pain, mild pain, moderate pain, severe pain, very severe pain). Results: A total of 26 patients met the inclusion criteria. The average age was 17.7 years and the average Cobb angle was 41.5°. Nineteen patients (73.1%) experienced mild or moderate chronic low back pain before treatment and seven patients (26.9%) were asymptomatic but seeking treatment for cosmetic reasons. At follow-up, a 23% correction of the curve was achieved. All previously symptomatic patients reported that they no longer experienced low back pain after having worn the brace regularly. Conclusion: High correction bracing seems to have a positive effect on the curve and on chronic low back pain in patients with a scoliosis and a Lenke 5C curve pattern. Clinical implications: High correction, pattern specific bracing with a GBW may be applied aiming at reducing structural curves and chronic low back pain in late adolescent and adult patients with AIS and with a single lumbar curvature.

Upper Extremity Skeletal Muscle Mass Asymmetry Exacerbated by Shoulder Imbalance in Lenke1A Adolescent Idiopathic Scoliosis.

Limb muscle strength asymmetry affects many physical abilities. The present study (1) quantified limb muscle asymmetry in patients with adolescent idiopathic scoliosis (AIS); (2) compared AIS patients with major thoracolumbar/lumbar (TL/L) or major thoracic (MT) curves; (3) examined correlations between limb muscle asymmetry and radiographic parameters. Patients with AIS with major TL/L curves (Lenke type 5C) and MT curves (Lenke Type 1A) who underwent posterior spinal fusion at our university hospitals were included. Patients with left hand dominance were excluded. Body composition was measured using whole-body dual-energy X-ray absorptiometry and asymmetry of left and right side skeletal muscles were evaluated. Upper extremity skeletal muscles on the dominant side were significantly larger than those on the nondominant side in both Lenke1A and 5C groups. The asymmetry of upper extremity skeletal muscles was significantly greater in the Lenke1A group than in the Lenke5C group. Additionally, the size of the asymmetry did not correlate with the magnitude of the major curve and rotational deformation but did correlate with a right shoulder imbalance in the Lenke1A group. These results suggest that in AIS with a constructive thoracic curve, right shoulder imbalance is an independent risk factor for upper extremity skeletal muscle asymmetry.

Spontaneous Improvement of Postoperative Coronal Imbalance Following Selective Thoracolumbar-Lumbar Fusion in Lenke 5C Adolescent Idiopathic Scoliosis.

OBJECTIVE: To evaluate prevalence and prognosis of postoperative coronal imbalance (CIB) and factors related to its onset and spontaneous improvement in patients with Lenke 5C adolescent idiopathic scoliosis who underwent selective thoracolumbar-lumbar fusion. METHODS: We measured radiographic parameters and evaluated clinical outcomes using the Scoliosis Research Society-22 questionnaire in patients with Lenke 5C adolescent idiopathic scoliosis and a minimum 2-year follow-up. CIB was defined as >2 cm distance between C7 plumb line and central sacral vertical line. We compared parameters between patients with CIB (CIB group) and without CIB (coronal balanced group). RESULTS: Inclusion criteria were met by 29 patients (mean age at surgery:17.0 years; average follow-up period: 45.6 months). CIB was found in 10 patients 1 week after surgery (34.5%); this decreased to 6.9% at final follow-up. Comparative analysis indicated significant values as follows: age at surgery (17.5 years vs. 14.7 years, P = 0.005), lumbosacral curve (5.9° vs. 11.2°, P = 0.02), and L5 tilt (-3.6° vs. -8.1°, P = 0.02) in bending film. Greater changes of lowest instrumented vertebra disc angle, which means scoliotic angles between LIV and LIV+1, were significantly associated with spontaneous improvement of CIB (P = 0.04). Clinical outcomes were comparable between the coronal balanced and CIB groups. CONCLUSIONS: Although CIB was frequently detected in the early postoperative period after selective thoracolumbar-lumbar fusion, it mostly corrected spontaneously. Relatively younger age at surgery and less flexible lumbosacral curve may be related to postoperative CIB, and greater changes of LIV disc angle may be associated with spontaneous improvement of CIB.

Anterior Spinal Fusion and Posterior Spinal Fusion Both Effectively Treat Lenke Type 5 Curves in Adolescent Idiopathic Scoliosis: A Multicenter Study.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: Retrospective comparison of radiographic and clinical outcomes between anterior spinal fusion (ASF) and posterior spinal fusion (PSF) in surgical treatment of Lenke 5 curves. SUMMARY OF BACKGROUND DATA: ASF and PSF are used for treatment of Lenke 5 curves in patients with adolescent idiopathic scoliosis (AIS). Currently, no consensus exists for optimal surgical treatment of Lenke 5 curves. METHODS: Patients with Lenke 5 curves treated with either ASF or PSF were prospectively enrolled in a multicenter database and then retrospectively reviewed. Demographic data, perioperative measures, radiographic data, and SRS-22R scores were collected and compared for statistical significance. RESULTS: A total of 149 patients were included in the study; 51 underwent PSF and 98 underwent ASF. There was no difference in demographics between groups. The PSF group was fused one level longer than the ASF group (5.9 levels PSF, 4.6 levels ASF, p < .0001). The PSF group had shorter operative times (223 minutes PSF, 297 minutes ASF; p < .0001) and a higher proportion of patients who received a postoperative blood transfusion (45% vs. 5%, p < .0001). PSF patients had longer hospital stays (6.1d PSF vs. 5d ASF, p = .031). The ASF group had larger preoperative major curve (48.2° ASF, 44.2° PSF; p < .01). Coronal balance, thoracolumbar/lumbar Cobb angle, shoulder height, trunk shift, and overall sagittal balance were not different between groups at two-year follow-up. Curve correction at two-year follow-up was similar between groups (66% ASF vs. 62% PSF). There were no significant differences in clinical outcomes or complication rates between groups. CONCLUSION: There is no difference in radiographic or clinical outcomes in patients treated with ASF or PSF for Lenke 5 curves. ASF may save a fusion level, but has longer operative time than PSF. Ultimately, the risks and benefits of each approach merit consideration by surgeon and patient. LEVEL OF EVIDENCE: Level II.

Comparison of Clinical and Radiologic Outcome of Three-Dimensional Correction in Lenke 5C Curve: Uniplanar Versus Polyaxial Pedicle Screws.

OBJECTIVE: To evaluate radiologic and clinical outcome of three-dimensional correction using the uniplanar pedicle screw (UPS) combined with vertebral body derotation technique for treatment of Lenke 5C adolescent idiopathic scoliosis. METHODS: Fifty patients treated with posterior selective fusion by UPS or polyaxial pedicle screw (PPS) were enrolled. Radiologic parameters, including degree of main curve, thoracic kyphosis, lumbar lordosis, and apical vertebral rotation, were evaluated preoperatively, postoperatively, and at a minimum 2-year follow-up. Scoliosis Research Society Version 22 questionnaire was assessed preoperatively and at 2-year follow-up. RESULTS: Preoperative lumbar Cobb angle was 48.9° in the UPS group and 49.1° in the PPS group (P = 0.59). Postoperatively, no difference in the correction of the main curve magnitude between the 2 groups was observed (74.4% vs. 73.9%, P = 0.74). Correction rate of apical vertebral rotation in the UPS group was significantly higher compared with the PPS group. No difference in average thoracic kyphosis and lumbar lordosis was observed between the 2 groups. At last follow-up, Scoliosis Research Society Version 22 scores were improved in both groups, of which the self-image score in the UPS group was significantly higher compared with the PPS group. CONCLUSIONS: The application of UPS combined with vertebral body derotation technique can reduce vertebral rotation and obtain better patient self-image score when favorable coronal and sagittal realignment is achieved. This improvement remains superior during 2-year follow-up. This combined application is a promising option to achieve spinal three-dimensional correction in treating Lenke 5C curve.

Spontaneous correction of coronal imbalance after selective thoracolumbar-lumbar fusion in patients with Lenke-5C adolescent idiopathic scoliosis.

BACKGROUND CONTEXT: Coronal imbalance is a complication of corrective surgeries in adolescent idiopathic scoliosis (AIS). However, few studies about immediate coronal decompensation in Lenke-5C curves have reported its incidence, prognosis, and related factors. PURPOSE: To evaluate the development of coronal imbalance after selective thoracolumbar-lumbar (TL/L) fusion (SLF) in Lenke-5C AIS, and to reveal related factors. STUDY DESIGN: Retrospective comparative study. PATIENT SAMPLE: This study included 50 consecutive patients with Lenke-5C AIS who underwent SLF at a single center. OUTCOME MEASURES: Whole-spine anteroposterior and lateral radiographs were used to measure radiological parameters. METHODS: Patients were divided into two groups according to the presence or absence of coronal imbalance (distance between C7 plumb line and central sacral vertical line >2 cm) in the early (1 month) postoperative period. Various radiological parameters were statistically compared between groups. RESULTS: Of the patients, 28% (14 of 50) showed coronal imbalance in the early postoperative period; however, most of them (13 of 14) showed spontaneous correction during follow-up. The development of coronal imbalance was related to less flexibility of the TL/L curve (51.3% vs. 52.6%, p=.040), greater T10-L2 kyphosis (11.7° vs. 6.4°, p=.034), and greater distal junctional angle (6.0° vs. 3.7°, p=.025) in preoperative radiographs. Lowermost instrumented vertebra (LIV) tilt was greater in the decompensation [+] group in the early postoperative period (8.8° vs. 4.4°, p=.009). However, this difference disappeared in final follow-up with the decrease of LIV tilt in the decompensation [+] group. CONCLUSIONS: Less flexibility of the TL/L curve, greater TL kyphosis, and greater distal junctional angle preoperatively were predictive factors for immediate coronal imbalance in Lenke-5C curves. Although coronal imbalance was frequently detected in the early postoperative period after SLF, it was mostly corrected spontaneously with a decrease of LIV tilt. Thus, SLF for Lenke-5C curves can be a good option regardless of the possible coronal imbalance in the early postoperative period.

Radiological factors affecting post-operative global coronal balance in Lenke 5 C scoliosis.

BACKGROUND: Lenke 5 C curves are frequently associated with clinically and radiological coronal imbalance. Appropriate selection of proximal and distal levels of fusion is essential to ensure good coronal balance (CB). We aimed to evaluate radiological factors associated with (I) global CB in the early post-operative period; (II) late decompensation of CB; and (III) favourable spontaneous correction of CB on long term follow up. METHODS: Twenty-three Lenke type 5C scoliosis cases treated with selective posterior lumbar instrumentation were retrospectively evaluated. Pre-operative, early post-operative and late post-operative (>2 years) whole length radiographs were analysed. Cobb's angle, lumbar lordosis, coronal imbalance, lower instrumented vertebra (LIV) tilt and translation and upper instrumented vertebra (UIV) tilt and translation were measured. The proximal and distal fusion levels were noted and correlated with post-operative CB. RESULTS: There were 21 females and 2 males with a mean follow up of 36 months. The mean pre-operative cobb angle was 55°±13.26°, which corrected to 14.7°±8.84° and was maintained on follow up. Eight patients had early post-operative coronal imbalance with spontaneous resolution seen in six cases on long term follow-up. At final follow-up, four cases had coronal imbalance (persistent imbalance since early post-operative period =2; late decompensation =2). In cases with early imbalance 5/8 cases had a pre-operative LIV tilt of ≥25°. All four patients with coronal imbalance at final follow-up had pre-operative LIV tilt ≥25°. Radiographic parameters which correlated with post-operative coronal imbalance were pre-operative LIV tilt (r=0.64, P=0.001), pre-operative LIV translation (r=0.696, P<0.001), pre-operative UIV translation (r=0.44, P=0.030), post-operative LIV tilt (r=0.804, P<0.001), and post-operative UIV tilt (r=0.62, P=0.001). CONCLUSIONS: In Lenke 5C scoliosis, a pre-operative LIV tilt ≥25° significantly correlates with post-operative global coronal imbalance. Increasing UIV tilt may be a factor that accounts for improvement of CB in late follow-up period.

Anterior versus posterior approach in Lenke 5C adolescent idiopathic scoliosis: a meta-analysis of fusion segments and radiological outcomes.

BACKGROUND: Radiological outcomes between anterior and posterior approach in Lenke 5C curves were still controversial. Meta-analysis on published articles to compare fusion segments and radiological outcomes between the two surgical approaches was performed. METHODS: Electronic database was conducted for searching studies concerning the anterior versus posterior approach in Lenke 5C curves. After quality assessment, data of means, standard deviations, and sample sizes were extracted. RevMan 5.3 was adopted for data analysis. RESULTS: Seven case-control studies involving 308 Lenke 5C AIS patients were identified in the meta-analysis. No significant differences were noted in correction rate of thoracolumbar/lumbar curve (95 % CI -6.02 to 4.32, P = 0.75) and incidence of proximal junctional kyphosis (95 % CI 0.12 to 7.19, P = 0.94) of final follow-up, in change values of thoracolumbar/lumbar curve (95 % CI -3.28 to 7.19, P = 0.46) and thoracic kyphosis (95 % CI -4.10 to 0.13, P = 0.07). The anterior approach represented a significant shorter fusion segments compared to posterior approach (95 % CI -1.72 to -0.71, P < 0.00001). The posterior approach obtained a larger increasing Cobb angle of lumbar lordosis than the anterior approach (95 % CI -6.06 to -0.61, P = 0.02). CONCLUSIONS: The anterior and posterior approach can obtain comparable coronal correction, change values of thoracic kyphosis, and incidence of proximal junctional kyphosis. The anterior approach saves approximate one more fusion segment, and the posterior approach can obtain a larger increasing Cobb angle of lumbar lordosis, from preoperation to final follow-up. TRIAL REGISTRATION: The article type of this study is meta-analysis and prospective registration is not required.

Selection of the upper vertebra to be instrumented in the treatment of thoracolumbar and lumbar adolescent idiopathic scoliosis by anterior correction and fusion surgery using dual-rod instrumentation: a minimum 12-year follow-up study.

BACKGROUND CONTEXT: Consensus regarding the optimal upper vertebra to be instrumented during surgical treatment of Lenke 5C thoracolumbar and lumbar adolescent idiopathic scoliosis (AIS) remains limited. PURPOSE: This study aimed to assess whether a short fusion strategy is appropriate for correction of a Lenke 5C AIS curve by anterior correction and fusion surgery using dual-rod instrumentation. STUDY DESIGN: This study design used retrospective comparative analysis of a prospectively collected, consecutive, non-randomized series of patients at a single institution. PATIENT SAMPLE: Thirty consecutive patients with Lenke 5C AIS treated with anterior correction and fusion surgery using dual-rod instrumentation were included. OUTCOME MEASURES: Patient demographics, radiographic measurements, and Scoliosis Research Society-22 questionnaire (SRS-22) scores were the outcome measures for this study. METHODS: Thirty patients were treated surgically for AIS with a Lenke 5C curve (mean age, 14.4 years [11-19 years)]) and followed up for a mean period of 17.2 years (12-23 years). Radiographical parameters and clinical outcomes were compared between patients treatment with the end vertebra (EV) instrumented (n=14) and those treated by short fusion (S group) with instrumentation starting at the vertebra one level caudal to the EV (n=16 patients). There were no study-specific biases related to conflicts of interest. RESULTS: In the EV group, a mean preoperative Cobb angle of 56° was corrected to 5° after surgery and to 8° at the final follow-up. In the S group, a mean preoperative Cobb angle of 55° was corrected to 10° after surgery and 14° at the final follow-up. The mean correction rate at the final follow-up was significantly lower in the S group (74%) than in the EV group (86%; p=.020). The coronal and sagittal balance, thoracic kyphosis, lumbar lordosis, and clinical outcomes evaluated using SRS-22 did not differ between the two groups. CONCLUSIONS: The short fusion strategy, which involves instrumentation of the vertebra one level caudal to the upper EV, can be considered as an alternative to the conventional strategy, which includes instrumentation of the upper EV, for treating Lenke 5C curves via anterior spinal fusion.

Anterior Dual Rod Versus Posterior Pedicle Fixation Surgery for the Surgical Treatment in Lenke 5C Adolescent Idiopathic Scoliosis: A Multicenter, Matched Case Analysis of 42 Patients.

STUDY DESIGN: Multicenter matched case analysis. OBJECTIVE: Compare patients with Lenke 5C scoliosis surgically treated with anterior spinal fusion with dual rod instrumentation and anterior column support versus posterior release and pedicle screw instrumentation. SUMMARY OF BACKGROUND DATA: Treatment of single, structural, lumbar and thoracolumbar curves in patients with adolescent idiopathic scoliosis (AIS) has been the subject of some debate. Previous papers directly comparing these approaches are problematic because of heterogeneity of the groups, nonrandomized protocols, and surgeon bias and variation of instrumentation (upper instrumented vertebrae and lower instrumented vertebrae) in relation to the defined Cobb angle (upper end vertebra and lower end vertebrae). This report sought to remedy these flaws by analyzing a database of Lenke 5C AIS and performing matched cases. METHODS: We analyzed 96 patients with Lenke 5C AIS curves based on radiographic and clinical data at 3 institutions, surgically treated between 2001 and 2005 with minimum 2-year follow-up. Case matched criteria (age within 1 year, sex, curve within 5°, lower end vertebrae, and lower instrumented vertebrae) yielded 21 matched patient pairs. We evaluated and compared multiple clinical and radiographic parameters. RESULTS: We observed no significant statistical differences between groups in any preoperative clinical or radiographic parameters. At final follow-up, the major curve measured 8° (83%) in the posterior spinal fusion group, compared with 13° (72%) in the anterior spinal fusion group (p = .002). Estimated blood loss was similar in both groups. Hospital stay was significantly shorter in the posterior spinal fusion group. There were no differences in radiographic complications, such as proximal junctional kyphosis. CONCLUSIONS: At a minimum of 2 years' follow-up in a multicenter, matched case analysis, adolescents with Lenke 5C curves demonstrated statistically significantly better curve correction and shorter hospital stays when treated with a posterior release with pedicle screw instrumented fusion compared with an anterior instrumented fusion with dual rods for similar patient populations.

Cifosis de unión proximal en curvas Lenke 5C. Comparación entre cirugía anterior y cirugía posterior / Proximal junctional kyphosis in lenke c5 curves. A comparison between anterior and posterior surgery

Introducción: El balance sagital es crítico para los resultados a largo plazo en el manejo quirúrgico de la escoliosis idiopática del adolescente. La cifosis de unión se podría definir como un hallazgo radiológico en la transición de la columna fusionada y la columna móvil en pacientes asintomáticos. El objetivo de este trabajo fue comparar la cifosis de unión proximal posoperatoria en curvas Lenke 5C con dos técnicas quirúrgicas distintas: la instrumentación anterior y la instrumentación posterior. Materiales y Métodos: Estudio retrospectivo, controlado no aleatorizado, de 37 pacientes con escoliosis idiopática del adolescente, curvas Lenke 5C con fusión corta, de vértebra límite a vértebra límite. Grupo 1: 18 pacientes con artrodesis anterior instrumentada y Grupo 2: 19 pacientes con artrodesis posterior instrumentada. Los parámetros sagitales radiológicos medidos fueron: 1) línea de plomada de C7, 2) cifosis de unión, 3) cifosis torácica, 4) lordosis lumbar, con un seguimiento mínimo de 2 años. Resultados: Grupo 1: aumento de la cifosis de unión entre el preoperatorio y el seguimiento a los 2 años de 6,27° (p = 0,0002). La incidencia de cifosis de unión patológica fue del 17 por ciento. Grupo 2: aumento de la cifosis de unión entre el preoperatorio y el seguimiento de 4,63° (p = 0,0004). La incidencia de cifosis de unión patológica fue del 16 por ciento. Conclusión: No hubo diferencias significativas entre ambos grupos en la incidencia de cifosis de unión patológica.

Background: Sagittal balance is critical for long-term results in the surgical handling of adolescent idiopathic scoliosis. Proximal junctional kyphosis could be defined as a radiographic findings in the fused and mobile spine transition in asymptomatic patients. Objective: To compare post-surgical proximal junctional kyphosis in Lenke C5 curves with two different surgical techniques: anterior and posterior instrumentation. Methods: Retrospective, controlled, non-randomized study of 37 patients with Lenke C5 adolescent idiopathic scoliosis, with short fusion from end-vertebra to end-vertebra. Group 1: 18 patients with anterior instrumented arthrodesis, and Group 2: 19 patients with posterior instrumented arthrodesis. The radiographic sagittal parameters measured were: 1) plumbline from the C7, 2) junctional kyphosis, 3) thoracic kyphosis, and 4) lumbar lordosis; with a minimum follow-up of two years. Results: Group 1: increase of junctional kyphosis between the preoperative period and a two-year follow-up, 6.27° (p = 0.0002). The incidence of pathologic junctional kyphosis was 17%. Group 2: increase of junctional kyphosis between the preoperative period and the follow- up, 4.63° (p = 0.0004). The incidence of pathologic junctional kyphosis was 16%. Conclusion: There were no significant differences between groups in the incidence of pathologic junctional kyphosis.

Cifosis de unión proximal en curvas Lenke 5C. Comparación entre cirugía anterior y cirugía posterior / Proximal junctional kyphosis in lenke c5 curves. A comparison between anterior and posterior surgery

Introducción: El balance sagital es crítico para los resultados a largo plazo en el manejo quirúrgico de la escoliosis idiopática del adolescente. La cifosis de unión se podría definir como un hallazgo radiológico en la transición de la columna fusionada y la columna móvil en pacientes asintomáticos. El objetivo de este trabajo fue comparar la cifosis de unión proximal posoperatoria en curvas Lenke 5C con dos técnicas quirúrgicas distintas: la instrumentación anterior y la instrumentación posterior. Materiales y Métodos: Estudio retrospectivo, controlado no aleatorizado, de 37 pacientes con escoliosis idiopática del adolescente, curvas Lenke 5C con fusión corta, de vértebra límite a vértebra límite. Grupo 1: 18 pacientes con artrodesis anterior instrumentada y Grupo 2: 19 pacientes con artrodesis posterior instrumentada. Los parámetros sagitales radiológicos medidos fueron: 1) línea de plomada de C7, 2) cifosis de unión, 3) cifosis torácica, 4) lordosis lumbar, con un seguimiento mínimo de 2 años. Resultados: Grupo 1: aumento de la cifosis de unión entre el preoperatorio y el seguimiento a los 2 años de 6,27° (p = 0,0002). La incidencia de cifosis de unión patológica fue del 17 por ciento. Grupo 2: aumento de la cifosis de unión entre el preoperatorio y el seguimiento de 4,63° (p = 0,0004). La incidencia de cifosis de unión patológica fue del 16 por ciento. Conclusión: No hubo diferencias significativas entre ambos grupos en la incidencia de cifosis de unión patológica. (AU)

Background: Sagittal balance is critical for long-term results in the surgical handling of adolescent idiopathic scoliosis. Proximal junctional kyphosis could be defined as a radiographic findings in the fused and mobile spine transition in asymptomatic patients. Objective: To compare post-surgical proximal junctional kyphosis in Lenke C5 curves with two different surgical techniques: anterior and posterior instrumentation. Methods: Retrospective, controlled, non-randomized study of 37 patients with Lenke C5 adolescent idiopathic scoliosis, with short fusion from end-vertebra to end-vertebra. Group 1: 18 patients with anterior instrumented arthrodesis, and Group 2: 19 patients with posterior instrumented arthrodesis. The radiographic sagittal parameters measured were: 1) plumbline from the C7, 2) junctional kyphosis, 3) thoracic kyphosis, and 4) lumbar lordosis; with a minimum follow-up of two years. Results: Group 1: increase of junctional kyphosis between the preoperative period and a two-year follow-up, 6.27° (p = 0.0002). The incidence of pathologic junctional kyphosis was 17%. Group 2: increase of junctional kyphosis between the preoperative period and the follow- up, 4.63° (p = 0.0004). The incidence of pathologic junctional kyphosis was 16%. Conclusion: There were no significant differences between groups in the incidence of pathologic junctional kyphosis. (AU)