Patient-Specific Surgical Correction of Adolescent Idiopathic Scoliosis: A Systematic Review.

The restoration of sagittal alignment is fundamental to the surgical correction of adolescent idiopathic scoliosis (AIS). Despite established techniques, some patients present with inadequate postoperative thoracic kyphosis (TK), which may increase the risk of proximal junctional kyphosis (PJK) and imbalance. There is a lack of knowledge concerning the effectiveness of patient-specific rods (PSR) with measured sagittal curves in achieving a TK similar to that planned in AIS surgery, the factors influencing this congruence, and the incidence of PJK after PSR use. This is a systematic review of all types of studies reporting on the PSR surgical correction of AIS, including research articles, proceedings, and gray literature between 2013 and December 2023. From the 28,459 titles identified in the literature search, 81 were assessed for full-text reading, and 7 studies were selected. These included six cohort studies and a comparative study versus standard rods, six monocentric and one multicentric, three prospective and four retrospective studies, all with a scientific evidence level of 4 or 3. They reported a combined total of 355 AIS patients treated with PSR. The minimum follow-up was between 4 and 24 months. These studies all reported a good match between predicted and achieved TK, with the main difference ranging from 0 to 5 degrees, p > 0.05, despite the variability in surgical techniques and the rods' properties. There was no proximal junctional kyphosis, whereas the current rate from the literature is between 15 and 46% with standard rods. There are no specific complications related to PSR. The exact role of the type of implants is still unknown. The preliminary results are, therefore, encouraging and support the use of PSR in AIS surgery.

Enhanced recovery following posterior spinal fusion for adolescent idiopathic scoliosis: A medical and economic study in a French private nonprofit pediatric hospital.

INTRODUCTION: Little data exist on the efficacy of enhanced recovery after surgery (ERAS) protocols in patients undergoing posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS). HYPOTHESIS: ERAS reduces hospital costs (HC) and length of stay (LOS) without increasing pain or complications. MATERIALS AND METHODS: This was a retrospective comparative medical and economic study of 2 cohorts of patients who underwent PSF for AIS: a prospective group who underwent surgery with an ERAS protocol without a specially assigned care coordinator from 2020 to 2021 (n=30) and a retrospective group (control) who received standard care from 2017 to 2018 (n=30). The key amendments to the ERAS protocol were reduced preoperative investigations, opioid-sparing analgesia, ambulation starting on postoperative day (POD) 1, early resumption of oral diet, and early transition to oral analgesics. Moreover, an intensive care unit (ICU) stay, surgical drainage, and the postoperative CT scan were no longer routine. The discharge criteria were the same for both groups: normal bowel function, independent walking, pain Visual Analog Scale (VAS)<3 without strong opioids, and no signs of complications. The endpoints were: decreased HC (calculated by subtracting the costs of hospital days and complementary exams that were not carried out) and LOS, complications, and postoperative pain according to the VAS on POD 1, POD 3, and discharge. All means were reported with the standard deviation. RESULTS: The mean age of patients undergoing surgery (14.5±1.7 years), sex ratio, curve type according to the Lenke classification, mean Cobb angle (54±12°), and the number of instrumented vertebrae (9±2) were similar in both groups (p>0.5). The HC decreased on average by 3029€ per patient. The mean LOS was 5±0.9 days in the ERAS group versus 6.5±0.6 days in the control group (p<0.001). The VAS scores on POD 1 and POD 3 were lower in the ERAS group. One postoperative complication was noted in each group. CONCLUSION: Implementing an ERAS protocol without a specifically assigned care coordinator for patients with AIS undergoing PSF significantly decreased HC, LOS, and early postoperative pain. LEVEL OF EVIDENCE: III; retrospective comparative study.

Adolescent and Juvenile Idiopathic Scoliosis: Which Patients Obtain Good Results with 12 Hours of Cheneau-Toulouse-Munster Nighttime Bracing?

BACKGROUND: The results of 12 h nighttime Cheneau-Toulouse-Munster (CTM) brace wear on adolescent idiopathic scoliosis are poorly described. OBJECTIVE: The main objective was to analyze the efficiency of 12 h nighttime CTM brace wear on adolescent idiopathic scoliosis. The secondary objective was to identify the factors influencing good results. METHODS: One hundred and fifty consecutive patients treated between 2006 and 2017 were retrospectively analyzed with subgroup analysis for the main curve pattern (main thoracic or main lumbar). The inclusion criteria were evolutive scoliosis, 12 h nighttime CTM brace wear, Risser stages 0-1-2 at the time of the prescription, and Cobb angle below 45 degrees. Success was defined as no surgery, and the main curve Cobb angle (CA) progression ≤5°. The overcurve was defined as the proximal thoracic curve above the main thoracic and mid-thoracic above the main lumbar curves. A logistic regression model was built to assess the predictors of success. RESULTS: Overall success was 70%: 60% for main thoracic (MT) and 84% for main lumbar scoliosis (ML) (p = 0.003). Efficacy was 62% at Risser stage 0 and 78% at Risser stage 1-2 (p = 0.054). For MT, failure was associated with high in-brace sagittal C7 tilt (Odds Ratio = 0.72, p = 0.014) and low initial overcurve CA (Odds Ratio = 0.42, p = 0.044). For ML, a high standing height was associated with success (OR = 1.42, p = 0.035), and frontal unbalanced C7 tilt was associated with failure (OR = 0.43, p = 0.02). CONCLUSION: Twelve-hour nighttime CTM brace wear provided good results for main lumbar curves with balanced frontal C7 tilt. For MT, this treatment is indicated if the in-brace sagittal C7 tilt is well balanced from Risser stage 2.

Comparison of four correction techniques for posterior spinal fusion in adolescent idiopathic scoliosis.

INTRODUCTION: When performing posterior spinal fusion for adolescent idiopathic scoliosis (AIS), it is of major importance to address both coronal and sagittal deformities. Although several techniques have been described, few data exist comparing them. Our objective was to compare four techniques (in situ bending (ISB), rod derotation (RD), cantilever (C) and posteromedial translation (PMT)) for the correction of spinal deformity in AIS including thoracic deformity. MATERIAL AND METHODS: We conducted a multicenter retrospective study including 562 AIS patients with thoracic deformity with at least 24-month follow-up. Radiographic analysis was performed preoperatively, postoperatively and at last follow-up. The main outcomes were main curve correction and thoracic kyphosis restoration (TK). RESULTS: Coronal correction rate was significantly different among the four treatment groups (ISB 64% vs C 57% vs RD 55% vs PMT 67%, p < 0.001). Multivariate regression revealed that correction technique did not influence correction rate, whereas implant density, convex side compression and use of derotation connectors did. TK increase was significantly higher in the PMT group (average + 13°) than in DR (+ 3°), while ISB (-3°) and cantilever (-13°) resulted in TK decrease (p < 0.001). Multivariate analysis revealed that TK increase was only influenced by the reduction technique (p < 0.001) and preoperative TK (p < 0.001). DISCUSSION: The four techniques had the same ability to correct spinal deformity in the coronal plane. Three factors were identified to improve correction rate: implant density, convex compression and use of derotation connectors. On the other hand, PMT was more effective in restoring TK, particularly in hypokyphotic patients.

Clinical predictive model of lumbar curve Cobb angle below selective fusion for thoracic adolescent idiopathic scoliosis: a longitudinal multicenter descriptive study.

PURPOSE: To implement a clinically applicable, predictive model for the lumbar Cobb angle below a selective thoracic fusion in adolescent idiopathic scoliosis. METHODS: A series of 146 adolescents with Lenke 1 or 2 idiopathic scoliosis, surgically treated with posterior selective fusion, and minimum follow-up of 5 years (average 7) was analyzed. The cohort was divided in 2 groups: if lumbar Cobb angle at last follow-up was, respectively, ≥ or < 10°. A logistic regression-based prediction model (PredictMed) was implemented to identify variables associated with the group ≥ 10°. The guidelines of the TRIPOD statement were followed. RESULTS: Mean Cobb angle of thoracic main curve was 56° preoperatively and 25° at last follow-up. Mean lumbar Cobb angle was 33° (20; 59) preoperatively and 11° (0; 35) at last follow-up. 53 patients were in group ≥ 10°. The 2 groups had similar demographics, flexibility of both main and lumbar curves, and magnitude of the preoperative main curve, p > 0.1. From univariate analysis, mean magnitude of preoperative lumbar curves (35° vs. 30°), mean correction of main curve (65% vs. 58%), mean ratio of main curve/distal curve (1.9 vs. 1.6) and distribution of lumbar modifiers were statistically different between groups (p < 0.05). PredictMed identified the following variables significantly associated with the group ≥ 10°: main curve % correction at last follow-up (p = 0.01) and distal curve angle (p = 0.04) with a prediction accuracy of 71%. CONCLUSION: The main modifiable factor influencing uninstrumented lumbar curve was the correction of main curve. The clinical model PredictMed showed an accuracy of 71% in prediction of lumbar Cobb angle ≥ 10° at last follow-up. LEVEL OF EVIDENCE IV: Longitudinal comparative study.

Surgical increase in thoracic kyphosis predicts increase of cervical lordosis after thoracic fusion for adolescent idiopathic scoliosis.

PURPOSE: The modification of cervical lordosis (CL) after adolescent idiopathic scoliosis (AIS) surgery is influenced by the correction of thoracic hypokyphosis. The quantification of the increase of CL as a function of the increase of thoracic kyphosis (TK) has never been calculated. METHODS: A total of 92 consecutive AIS patients who underwent a posterior thoracic selective fusion, corrected by simultaneous translation on 2 rods technique, with minimum 24-month follow-up, were analyzed from a prospective database. We evaluated global sagittal kyphosis and lordosis. CL was divided by the horizontal line in proximal (PCL) and distal cervical lordosis (DCL), likewise TK in proximal (PTK) and distal TK (DTK), and lumbar lordosis (LL) in proximal (PLL) and distal LL (DLL). RESULTS: The mean TK gain was 16°, 14° and 28° in the whole cohort, normokyphosis group and hypokyphosis group, respectively. The mean DCL gain was, respectively, 9°, 7° and 20° and the mean CL gain 8°, 5° and 21°. There was a strong correlation between TK gain and CL gain (coefficient = 0.86) and between TK gain and DCL gain (coefficient = 0.74). The regression equation was defined as DCLgain = - 3 + 0.75 × TKgain (p < 0.0001) corresponding on average to 60% of the TK gain. CONCLUSION: 60% of the TK gain was transferred to DCL gain. Correlations reflect the geometrical equivalence between PTK and DCL. The use of sagittal global measurements shows that DCL is equivalent to PTK and can be expressed as a function of pelvic parameters (DCL = PT + LL-PI). DCL must be considered to optimize the postoperative sagittal alignment of the spine.

Proximal junctional kyphosis is a rebalancing spinal phenomenon due to insufficient postoperative thoracic kyphosis after adolescent idiopathic scoliosis surgery.

PURPOSE: Many authors tried to explain proximal junctional kyphosis (PJK) after adolescent idiopathic scoliosis (AIS) surgery by looking for risk factors. Latest publications focus on sagittal alignment. Each healthy adolescent has a specific thoracic kyphosis (TK) depending on their pelvic parameters and lumbar lordosis (LL). The objective of this work is to determine if the difference between TK at follow-up (TKFU) and the patient-specific TK (PSTK) plays a role in PJK occurrence after AIS surgery. The secondary objective was to find other risk factors. METHODS: We analyzed retrospectively 570 thoracic AIS who underwent a posterior thoracic fusion from nine centers. The series was separated in two groups: with and without PJK. PSTK was calculated with the formula PSTK = 2(PT + LL-PI). TK Gap was the difference between TKFU and PSTK. Logistic regression was utilized to test the impact of TK Gap and other known risk factors on PJK occurrence. RESULTS: Univariate analysis showed 15 factors significantly different between the groups. In a multivariate analysis, three factors had a strong significant influence on PJK: TKFU, TK Gain and TK Gap. Four additional factors affected the rate of PJK: Posterior translation on two rods, preoperative TK, preoperative LL and number of instrumented vertebrae. CONCLUSION: PJK is related to the insufficient TK at follow-up, compared to the specific TK that every patient should have according to their pelvic parameters. PJK incidence is significantly reduced by a strong gain in TK and a thoracic selective fusion which leaves the proximal lumbar vertebrae free. LEVEL OF EVIDENCE I: Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

Prevention of surgical site infections in pediatric spines: a single-center experience.

PURPOSE: To describe the potential issues in the methodology of surgical site infection (SSI) prevention and how it was investigated and corrected in a single institution. METHODS: A pediatric orthopedic unit experienced an increase of SSI, concerning up to 10% of scoliosis surgery cases from 2011 to 2013. An institutional procedure of multimodal and interdisciplinary risk evaluation was initiated, including a review of the literature, a morbi-mortality meeting, internal and external audits concerning the hygiene conditions in the operating room, the antibiotic prophylaxis, patients, and sterile material pathways. Several preventive actions were implemented, including the improvement of air treatment in the operating room, wound irrigation with 2L of saline before closure, application of topic vancomycine in the wound, verification of doses and timing of antibiotics injection, and use of waterproof bandages. We compared the rates of spine SSI before (retrospective group, 2011-2013) and after the implementation of various preventive measures (prospective group, 2014-2018). RESULTS: SSI occurred in 12 patients (6 idiopathic and 6 neuromuscular) out of 120 operated on (93 idiopathic, 18 neuromuscular, 9 others) in the retrospective group and 2 (both neuromuscular) out of 196 (150 idiopathic, 33 neuromuscular,13 others) in the prospective group (10% vs 1%, odds ratio=9.7, p=0.001). The groups were comparable for age, etiology, duration of surgery, body mass index, American Society of Anesthesiologists score, number of levels fused, and blood loss (p>0.2). CONCLUSION: The systematic analysis of SSI allowed for the understanding of the failures and correcting them. The current process is effectively preventing SSI. LEVEL OF EVIDENCE: 3: prospective series with case-control analysis.

Lumbopelvic parameters can be used to predict thoracic kyphosis in adolescents.

PURPOSE: Distal thoracic kyphosis (DTK) equivalent to proximal lumbar lordosis (PLL) is the sum of pelvic tilt (PT) and the difference (Δ) between lumbar lordosis (LL) and pelvic incidence (PI): PLL = DTK = PT + Δ. With the assumption that proximal thoracic kyphosis (PTK) is similar to DTK, we propose the equation TK = 2(PT + LL - PI) to express the relationship between thoracic kyphosis (TK) and pelvic parameters. The objective of this work is to verify this relationship in a normal population. METHODS: Full spine radiographs of 100 adolescents and young adults (13 to 20 years old), free from vertebral pathology, were analyzed. Measurements included pelvic parameters, LL, PLL, DLL, TK, PTK, DTK and C7 global tilt. The measured global TK was compared with the theoretical TK calculated according to the formula TK = 2(PT + LL - PI). RESULTS: The difference between measured TK and calculated TK was + 2.3° and correlated with the C7 global tilt (r = 0.86). There was a significant linear regression between TK and PT + ∆ (p < 0.0001). Given radiographs' inter-rater reliability of 5° for angled measurements, the p value (0.047) between measured TK and calculated TK is statistically significant to support the hypothesis. CONCLUSION: This work validates the formula TK = 2(PT + LL - PI) which allows the calculation of global TK as a function of PT, LL and PI. This calculated TK can be used as a target for sagittal correction of adolescents with spine deformities. These slides can be retrieved under Electronic Supplementary Material.

Patient-specific rods for thoracic kyphosis correction in adolescent idiopathic scoliosis surgery: Preliminary results.

INTRODUCTION: Restoring a degree of kyphosis consistent with good sagittal alignment of the spine is a key concern when performing surgery to correct adolescent idiopathic scoliosis (AIS). The objective of this study was to assess the preliminary outcomes of posterior fusion for AIS using patient-specific rods that were pre-contoured based on pelvic incidence. The primary evaluation criterion was thoracic kyphosis at last follow-up. HYPOTHESIS: The use of pre-bent patient-specific rods has a favourable effect on thoracic kyphosis at last follow-up. MATERIAL AND METHODS: A total of 37 patients with AIS, including 17 with hypokyphosis, managed with patient-specific rods were included in a prospective study. The rod contouring angles were based on predefined pelvic incidence criteria (25° to 40° for the rod on the convex side and the same value plus 10° for the rod on the concave side). Thoracic kyphosis was assessed before surgery and at last follow-up, after 12-36 months (mean, 19 months). Student's t test was applied to compare means. Multivariate linear regression analysis was performed. RESULTS: At last follow-up, the mean increase in kyphosis was 14° and was comparable to the planned increase (mean difference=0, p=0.85). Factors associated with kyphosis at last follow-up were the concave rod contouring angle and the pre-operative kyphotic angle of the thoracic segment to be instrumented (p<0.05). Mean differences between kyphosis of the instrumented thoracic segment at last follow-up and target kyphosis were -5° in the subgroup with hypokyphosis (<20°) before surgery and +4° in the subgroup with normal kyphosis before surgery. CONCLUSION: With patient-specific rods, kyphosis at last follow-up was close to the target value. Predictors of kyphosis at last follow-up were the concave rod contouring angle and pre-operative kyphotic angle of the thoracic segment to be instrumented. Over-contouring of the concave rod seems necessary in patients with preoperative hypokyphosis but not in patients with normal kyphosis. LEVEL OF EVIDENCE: III, prospective non-comparative study.

Surgical increase in thoracic kyphosis increases unfused lumbar lordosis in selective fusion for thoracic adolescent idiopathic scoliosis.

PURPOSE: In adolescent idiopathic scoliosis (AIS), there is a close relationship between thoracic kyphosis (TK) and proximal lumbar lordosis (PLL). The hypothesis states correction of hypokyphosis increases lumbar lordosis (LL) through increase in PLL after surgical correction of TK. METHODS: 111 consecutive thoracic AIS, Lenke 1 or 2 who underwent posterior selective thoracic fusion with reduction by simultaneous translation on 2 rods and 2 years follow-up have been prospectively selected and analyzed. Instrumentations below L1 and anterior releases were excluded. Global TK and LL were measured by a dedicated software. Mean values were compared through T test, correlations assessed through Pearson's coefficient. RESULTS: Global TK increased from 27° to 46° at the last follow-up (p < 0.0001) and LL from 58° to 65° (p < 0.0001). PLL increased by 8° (15°-23°), and distal lumbar lordosis remained stable (42°). The gains were higher for the Hypo-Kyphosis group than for the Normo-Kyphosis group (p < 0.001). There was a strong correlation (coef = 0.65) between TK and PLL as well as between the gain of TK and the gain of PLL (coef = 0.70). LL increased after the first postoperative month. At 1 month, there was a significant increase in pelvic tilt and decrease in sacral slope, offsetting the LL increase, and indicating a temporary pelvic retroversion. CONCLUSIONS: Increase in TK led to increase in uninstrumented LL through increase in PLL with a continuous correlation between TK and PLL. These results allow surgeons to calculate the TK required during surgical correction of thoracic AIS to adapt LL to pelvic incidence. These slides can be retrieved under Electronic Supplementary Material.

Can Gartland II and III supracondylar humerus fractures be treated using Blount's method in the emergency room?

BACKGROUND: Studies have established that Blount's method is reliable for treating extension supracondylar fractures (SCFs) in paediatric patients. Reduction in the emergency room (ER) under procedural sedation followed by orthopaedic treatment is increasingly used for many fracture types. The primary objective of this study was to determine whether SCF reduction in the ER was feasible, by determining the failure rate. The secondary objective was to identify causes of failure with the goal of improving patient selection to reduction in the ER. HYPOTHESIS: Gartland II and III SCFs (Lagrange-Rigault grades 2-4) can be treated in the emergency room under fluoroscopic guidance and with procedural sedation. MATERIAL AND METHODS: A retrospective study was conducted in 128 paediatric patients who underwent ER reduction of an SCF in 2014-2015. Mean age was 5.6 years. Reduction was performed either by an orthopaedic surgery resident or by a specially trained emergency physician. RESULTS: Of the 128 SCFs, 101 (79%) were Gartland II and 27 Gartland III. In the Lagrange-Rigault classification, 55 (43%) fractures were grade 2, 59 (46%) were grade 3, and 14 (11%) were grade 4. The arm was immobilised using the cuff-and-collar method described by Blount for 4 weeks. All 128 fractures healed without delay. Blount's method alone was effective in 112 (87.5%) patients. Of the 16 other patients, 15 (Lagrange-Rigault 3, n=14; and 4, n=1) had an unstable fracture after ER reduction and were managed by reduction and internal fixation in the operating room. The remaining patient (0.5%) experienced secondary displacement requiring revision surgery in the operating room. CONCLUSION: SCFs grades 2 to 4 in the Lagrange-Rigault classification (Gartland II and III) can be treated in the ER by specially trained physicians. Lagrange-Rigault grade 3/Gartland III SCFs are more likely to require subsequent internal fixation but do not contraindicate reduction in the ER. LEVEL OF EVIDENCE: IV, retrospective study.

Cobalt-chrome and titanium alloy rods provide similar coronal and sagittal correction in adolescent idiopathic scoliosis.

BACKGROUND: Cobalt-chrome (CoCr) and the titanium alloy TA6V (Ti) are the materials most widely used for spinal instrumentations in patients with adolescent idiopathic scoliosis (AIS). The objective of this work was to compare the effectiveness of CoCr and Ti rods in terms of coronal and sagittal correction by pedicle screw constructs in patients with AIS. HYPOTHESIS: Correction is similar with CoCr and Ti rods in patients with AIS. MATERIAL AND METHOD: A retrospective single surgeon study was conducted in patients with AIS managed using pedicle screw posterior spinal fusion with high implant density and reduction by postero-medial translation. Follow-up was more than 2 years in all patients. Patients were divided into two groups based on whether the rods used were made of CoCr (n=30) or Ti (n=33). The groups were identical for age, Risser classification, follow-up duration, type of curve, and implant density. Coronal and sagittal parameters on standing full-spine radiographs were analysed using graphics software before surgery then 1 month after surgery and at last follow-up. Quantitative data were compared by applying Student's t test. RESULTS: The percentage of main curve correction at last follow-up was the same in the two groups (76%/75%) (p=0.7). Gains in thoracic kyphosis (12°/13°) and lumbar lordosis (8°/10°) were not significantly different between groups. At last follow-up, 3 patients had proximal junctional kyphosis, 1 in the CoCr group and 2 in the Ti group (p=0.6). CONCLUSION: For posterior spinal fusion to treat AIS, with a high density of pedicle screws, correction by translation, and 6 mm rods, CoCr rods and Ti rods produce the same amount of coronal and sagittal correction. LEVEL OF EVIDENCE: IV, comparative retrospective study with no control group.

Proximal junctional kyphosis in thoracic adolescent idiopathic scoliosis: risk factors and compensatory mechanisms in a multicenter national cohort.

INTRODUCTION: Proximal junctional kyphosis (PJK) is a frequent complication, up to 46%, in adolescent idiopathic scoliosis surgical treatment (AIS). Several risk factors have been evoked but remain controversial. The purpose of this study was to analyze the incidence of PJK in a multicenter cohort of AIS patient and to determine risk factor for PJK. MATERIALS AND METHODS: Lenke I and II AIS patients operated between 2011 and 2015 (minimum of 2-years follow-up) were included. On fullspine X-rays, coronal and sagittal radiographic parameters were measured preoperatively, postoperatively and at final follow-up. Occurrence of radiological PJK corresponding to a 10° increase in the sagittal Cobb angle, measured between the upper instrumented vertebra (UIV) and UIV + 2, between postoperative and 2-years follow-up X-rays, was reported. RESULTS: Among the 365 patients included, 15.6% (n = 57) developed a PJK and only 10 patients required a revision surgery. Preoperatively, PJK patients had significantly larger pelvic incidence (57° ± 13° vs. 51° ± 12°), larger lumbar lordosis (LL) (63° ± 12° vs. 57° ± 11°) and bigger C7 slope. Postoperatively (3 months), in the non-PJK group, thoracic kyphosis (TK) was increased and LL was not significantly different. However, postoperatively, in the PJK group, no significant change was observed in TK, whereas C7 slope decreased and LL significantly increased. There was also a postoperative change in inflection point which was located at a more proximal level in the PJK group. Between postoperative time and final follow-up, TK and LL significantly increased in the PJK group. CONCLUSION: PJK is a frequent complication in thoracic AIS, occurring 16%, but remains often asymptomatic (less than 3% of revisions in the entire cohort). An interesting finding is that patients with high pelvic incidence and consequently large LL and TK were more at risk of PJK. As demonstrated in ASD, one of the causes of PJK might be postoperative posterior imbalance that can be due to increased LL, insufficient TK or inflection point shift during surgery. These slides can be retrieved under Electronic Supplementary Material.

Influence of Derotation Connectors on 3D Surgical Correction of Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Monocentric study comparing results of simultaneous translation on 2 rods (ST2R) with derotation connectors (prospective series) or without derotation connectors (retrospective series) in Adolescent Idiopathic Scoliosis (AIS) surgery. OBJECTIVE: The objective of this study was to assess if derotation connectors influence axial, coronal, and sagittal results in AIS surgery. SUMMARY OF BACKGROUND DATA: Conventional reduction techniques remain limited in their ability to reduce axial torsion. Direct vertebral derotation technique accomplishes partial axial derotation but decreases thoracic kyphosis. METHODS: Monocentric study including AIS surgeries performed using ST2R technique with derotation connectors (group D+, n=44) or without derotation connectors (group D-, n=24). The axial intervertebral rotation was measured between apical and neutral vertebra on pre and postoperative computed tomography scan. T test was used to compare mean values. ANCOVA analyzed the influence of connectors and covariates on the primary outcome, which was the difference between preoperative and postoperative intervertebral rotation. RESULTS: The mean axial torsion gain in the D+ group was 23% (+3.84 degrees, 95% confidence interval, +1.95/+5.73). In the D- group, mean axial torsion increase of 4% (-0.42 degrees, 95% confidence interval, -1.19/+2.03). The result was significantly different between the 2 groups (P=0.005). The coronal correction of the main curve angle was 80% in the D+ group and 64% in the D- group (P=0.004). Kyphosis correction was similar between the 2 groups (P=0.3) with significant increase of thoracic kyphosis in the whole series (P=0.02) and no patients with postoperative hypokyphosis <10 degrees. Multivariate analysis confirmed the influence of derotation connectors on both axial and coronal correction (P<0.05). CONCLUSIONS: The use of derotation connectors in the surgical treatment of AIS significantly improved axial and coronal correction compared to nonuse of connectors without compromising the sagittal plane.

Prognostic Role of Rib Hump in Overlying Thoracic Curve Correction Above Selective Fusion for Lenke 5 Idiopathic Adolescent Scoliosis.

STUDY DESIGN: Prospective study. OBJECTIVE: To assess whether rib hump is a prognostic factor of final thoracic Cobb angle. SUMMARY OF BACKGROUND DATA: Correction of thoracolumbar/lumbar curve, preoperative thoracic curves angle, thoracic curves angle on bending, the thoracolumbar-lumbar angle/thoracic curves angle ratio, thoracic kyphosis, and growth stage influences spontaneous correction of uninstrumented thoracic curves angle above selective fusion for Lenke 5 Adolescent Idiopathic Scoliosis. Indeed, preoperative rib hump has never been expressly evaluated as a prognostic factor of final thoracic curves angle. METHODS: In total, 50 patients with Lenke 5 Adolescent Idiopathic Scoliosis, selectively instrumented with posterior construct were included. Two patients were lost to follow-up and 48 had follow-up ≥2 years. Demographic data, preoperative thoracic rib hump (measured in millimeter in trunk anteflexion), and radiologic spinal parameters were recorded preoperatively and at last consultation. T test was used to compare mean values, linear and logistic regressions to assess predictability of final thoracic curve angle. RESULTS: Main thoracolumbar-lumbar curve angle decreased from 47 degrees (range, 36-72 degrees) to 12 degrees at the final consultation (range, 1-28 degrees). Thoracic curves angle decreased from 26 degrees (range, 2-40 degrees) preoperatively to 16 degrees (range, 2-41 degrees) at the final consultation (P=0.001) (correction=37%). Preoperative rib hump was present in 10 patients. Final thoracic Cobb angle was 27 degrees (8-41 degrees) in patients with rib hump and 14 degrees (0-32 degrees) in patients without rib hump (P<0.001).Multiregression highlighted thoracic curves angle on bending (P=0.001), preoperative thoracic curves angle (P=0.011) and rib hump (P=0.012) as prognostic factors of higher final thoracic curves angle. CONCLUSION: Rib hump significantly influenced final thoracic curves angle. LEVEL OF EVIDENCE: Level III-prospective study.

Advanced containment methods for Legg-Calvé-Perthes disease: triple pelvic osteotomy versus Chiari osteotomy.

INTRODUCTION: The goal of intervention in Legg-Calvé-Perthes disease (LCPD) is to prevent femoral head deformation by containing the head within the acetabulum. Currently, surgical containment methods are the mainstay of treatment, and pelvic osteotomies have been shown to be successful. They include triple pelvic osteotomy (TPO), Salter osteotomy, Chiari osteotomy and shelf procedure. The purpose of this study was to compare clinical and radiologic results for Chiari osteotomy and TPO in LCPD. METHODS: 29 children treated between 1980 and 2010 for LCPD in 2 centres were reviewed. 19 underwent TPO, and 10, Chiari osteotomy. Two independent observers assessed sequential radiographs and medical data. Each hip was preoperatively classed by clinical data, Catteral, Herring and Salter-Thompson classification, centre-edge angle (CE), and acetabular index (AI). The 2 groups were first tested for their comparability. After surgery the hips were classified by Stulberg classification, CE, AI, Harris Hip Score (HHS) and performance of further surgery. Chiari osteotomy and TPO have been secondary compared on these data by Wilcoxon test. RESULTS: Average follow-up was 4.2 years. The 2 groups were comparable before surgery. At first and last follow-up examination, statistically significantly superior results in patients with TPO regarding Stulberg classification (p = 0.01), AI (p = 0.002), pain (p = 0.02) and function (p = 0.01) in the HHS score were found. No differences were noticed concerning CE angle. CONCLUSIONS: In our series, TPO provided better radiologic and clinical outcomes compared to Chiari osteotomy, specially concerning the final Stulberg classification. We concluded that TPO should be preferred when indicated.

Infantile myofibromatosis of the iliac bone.

INTRODUCTION: Solitary infantile myofibromatosis (IM) of bone is a rare benign osseous tumor of childhood with low rate of recurrence. Well documented within the multicenter form, its solitary intraosseous location is less well described. CASE REPORT: We present a rare case of intraosseous myofibromatosis arising the iliac bone of a 11-year-old girl, who was operated at 2 months of life for a retroauricular subcutaneous MF with unbalanced translocation t(9;16). She presented with a limping associated to a stiffness of the hip without pain. Imaging disclosed a 4×4×1cm intraosseous, lytic and heterogeneous mass with a soft tissue component on the medial cortical of the left iliac bone. Open biopsy was performed. Histology revealed proliferation of fusiform cells with eosinophil cytoplasm embedded in a myxoid and fibrous stroma without mitotic figures. On immunohistochemistry, cells were positive for actin, PS100, KL1, focally positive for EMA, CD34, P63, rarely CD31, which indicated diagnosis of new localization of IM. Cytogenetic analysis revealed absence of translocation t(9;16), which was found in the first tumor. Subsequent total resection was performed. The patient recovered normal function without recurrence of tumor at 3 years follow-up. CONCLUSION: To our knowledge, this is the first case of solitary IM of the iliac bone, occurring 12 years after the first localization. Total resection resulted in excellent outcome. However recurrence can happen even long time after the first resection and new localization is possible, as in our case. This suggests close follow-up and clear information about the risk of recurrence.

Legg-Calvé-Perthes disease: classifications and prognostic factors.

INTRODUCTION: Legg-Calvé-Perthes Disease (LCPD) represents idiopathic avascular necrosis of femoral head in pediatric population. Indications for treatment depend mostly on prognosis about femoral head sphericity and hip congruence at the end of growth. The aim of this review is to highline prognostic factors of LCPD. METHODS: Bibliographic search in PubMed allowed selection of 33 articles concerning prognostic factors and/or classification of LCPD. CONCLUSION: Clinical factors of poor prognosis are overweight, female sex, age exceeding 6 years old, and lack of hip abduction. Radiologically, Herring's classification is consensual because of its high prognostic value and very good reproducibility. The other signs of femoral head "at-risk" and the assessment of the reduction in abduction of the femoral head in the acetabulum are also prognostic of late evolution. MRI seems to be a future tool in assessing the fate of hips in LCPD. It is likely that a better understanding of LCPD etiology would precise the prognosis of this disease.