Experimental validation of a new technique for the assessment of posterior tibial translation (ABC angle) after posterior cruciate ligament rupture.

BACKGROUND: The aim of this cadaver study was to evaluate an original technique for measuring posterior tibial translation based on an angle value instead of a distance value, with and without posterior stress application. It was hypothesized that an angle measurement of the posterior tibial translation would confirm the presence of a PCL tear with the knee flexed and completely extended. METHOD: Using fresh cadavers, a set of strict lateral views were taken by fluoroscopy with the knee at 0°, 45° and 90° flexion on the intact knee and after transecting the PCL. The primary endpoint was the change in the posterior translation measured using a new technique, the ABC angle. This measurement was compared to the conventional posterior translation distance measurement with and without a posterior stress placed on the knee. RESULTS: Application of a posterior stress revealed clear changes in posterior translation after PCL transection with the knee at 0° for the angle technique and at 45° and 90° for the two techniques (p < 0.05). Contrary to the reference method, the ABC angle method found a statistically significant difference in posterior translation with the knee in extension. CONCLUSION: Our technique provides a reliable radiographic measurement of posterior translation with the knee in extension, which should make it easier to acquire radiographs in patients who have pain with knee flexion. This angular measurement also has the advantage of not needing length calibration contrary to the reference technique. LEVEL OF EVIDENCE: IV.

Optimal Correction of Adult Spinal Deformities Requires Restoration of Distal Lumbar Lordosis.

PURPOSE: The aim of this study is to analyze results according to postoperative pelvic incidence-lumbar lordosis (PI-LL) mismatch in the management of adult spine deformity (ASD) patients. Recently, it has been reported that in addition to lumbar lordosis amount, lordosis repartition between its proximal and distal parts was crucial. METHODS: We enrolled 77 consecutive ASD patients who underwent posterior spinal fusion and deformity correction between 2015 and 2018. On preoperative and 1-year follow-up radiographs, we analyzed different parameters such as L1-S1 lumbar lordosis, L1-L4 proximal lordosis (PLL), L4-S1 distal lordosis (DLL), pelvic tilt (PT), sagittal vertical axis (SVA), and PI-LL mismatch. Comparisons were performed according to postoperative PI-LL mismatch (defined as "aligned" when PI-LL was <10°). The relationship between lordosis distribution and postoperative alignment status was investigated. RESULTS: On the whole series, average lumbar lordosis, SVA, and PI-LL improved (28.2° vs.43.5°, 82 vs. 51 mm, and 26°vs. 14°, all p < 0.001, respectively). On the other hand, PT remained unchanged (30° vs. 28°, p > 0.05). 35 patients were classified as "aligned" and 42 as "not aligned." Patients from the "aligned" group had a significantly lower PI than patients from the "not aligned" group (52° vs. 61°, p=0.009). Postoperative PLL was not different between groups (18° vs. 16° p > 0.05), whereas DLL was significantly higher in the "aligned" group (31° vs. 22°, p=0.003). PI-LL was significantly correlated to DLL (rho = 0.407, p < 0.001) but not with PLL (rho = 0.110, p=0.342). CONCLUSIONS: Our results revealed that in ASD patients, postoperative malalignment was associated with a lack of DLL restoration. "Not aligned" patients had also a significantly higher pelvic incidence. Specific attention must be paid to restore optimal distal lumbar lordosis in order to set the amount and the distribution of optimal postoperative lumbar lordosis.

Functional and surgical treatments in patients with spinal muscular atrophy (SMA).

Spinal muscular atrophies (SMA type 1, 2, 3) present with various severities according to the motor semeiology related to lesions of the peripheral nervous system (lesions of the anterior horn cells motoneuron or even brain stem). Early motor deficiency causes skeletal deformities responsible for the alteration or even absence of motor skills acquisition. The management of these patients involves several practitioners: pediatric neurologist, pediatric pneumologist, physical medicine and rehabilitation therapist, pediatric orthopedic surgeon, psychologist, physiotherapist, etc. Therefore, this multidisciplinary management must take place in a reference center. This has allowed for improvement of the natural history of SMA. Despite the severity of clinical presentation, especially in SMA type 1 or 2, the functional aspect is always to be taken into account in the first instance. Furthermore, the natural history of the disease is currently being modified by the emergence of innovative therapies that will change the evolution of the disease and its management. Indeed, current treatment objectives are the comfort of installation and the fight against neuro-orthopedic degradation. Although the rise in the number of innovative therapies has led to increased expectancies, such as motor function improvement, practitioners should be aware that these innovative treatments should be balanced against child development and the disease's natural history. Scoliosis surgery is almost systematic in SMA type 2 because of trunk muscular deficiency, especially intercostal muscle insufficiency, and spino-pelvic complex disorder. However, surgical techniques have evolved to become less invasive and more growth friendly in order to follow child development. The final goal of surgery in SMA patients is to obtain a 3-dimensional deformity correction along with a spino-pelvic realignment in order to allow for a comfortable seated position, which is the position of function in these patients, and to allow for better ventilation. Faced with this global approach and innovative therapies, global assessment is warranted not solely in an isolated manner, as is usually the case during hospital stays with traditional scales, but rather during daily activities. This is the case of daily monitoring, which allows for motor skill and activity assessments throughout the day. The principle is to characterize, according to SMA type and treatment, the activity type (standing, seated, walking), duration, intensity and frequency. The ultimate goal would be to identify the variety and occurrence of motor activities, and finally to clarify if the different treatments, including innovative therapies, lead to functional improvement in these patients. © 2020 French Society of Pediatrics. Published by Elsevier Masson SAS. All rights reserved.

Adult Spinal Deformities: Can Patient-Specific Rods Change the Preoperative Planning into Clinical Reality? Feasibility Study and Preliminary Results about 77 Cases.

Surgical management of adult spinal deformities remains challenging, and one of the major goals is to restore sagittal alignment. Spinal rods used for posterior fixation are usually delivered straight and bended manually during surgery. This manual bending can be responsible for undercorrection of the deformity. In the last years, prebended patient-specific rods have been developed and might be a valuable tool in order to optimize surgical results. The objective is therefore to use the time between surgical decision and operative room in order to realize a precise surgical planning and obtain patient-specific rods. We describe here the planning process and our preliminary experience with patient-specific rods in the management of adult deformity about 77 cases. On the 77 cases, PSR were used without further modifications of the shape. Based on 3-month postoperative evaluation, a significant decrease of sagittal vertical axis (-41%, p < 0.0001) and pelvic incidence-lumbar lordosis (-62%, p < 0.0001) was reported. Pelvic tilt was not significantly corrected, except in patients with Parkinson's disease. In this subgroup of patients, measurements revealed a significant correction of SVA and PI-LL (-53%, p=0.005, and -81%, p < 0.0001, respectively) but also of PT (-23%, p < 0.001). The use of PSR, in our experience, was feasible and provided satisfactory short-term results. It can be a valuable tool in the management of adult spinal deformities. Further studies will be needed in order to confirm these preliminary results.

Muscle Shortening and Spastic Cocontraction in Gastrocnemius Medialis and Peroneus Longus in Very Young Hemiparetic Children.

OBJECTIVES: Muscle shortening and spastic cocontraction in ankle plantar flexors may alter gait since early childhood in cerebral palsy (CP). We evaluated gastrosoleus complex (GSC) length, and gastrocnemius medialis (GM) and peroneus longus (PL) activity during swing phase, in very young hemiparetic children with equinovalgus. METHODS: This was an observational, retrospective, and monocentric outpatient study in a pediatric hospital. Ten very young hemiparetic children (age 3 ± 1 yrs) were enrolled. These CP children were assessed for muscle extensibility (Tardieu scale XV1) in GSC (angle of arrest during slow-speed passive ankle dorsiflexion with the knee extended) and monitored for GM and PL electromyography (EMG) during the swing phase of gait. The swing phase was divided into three periods (T1, T2, and T3), in which we measured a cocontraction index (CCI), ratio of the Root Mean Square EMG (RMS-EMG) from each muscle during that period to the peak 500 ms RMS-EMG obtained from voluntary plantar flexion during standing on tiptoes (from several 5-second series, the highest RMS value was computed over 500 ms around the peak). RESULTS: On the paretic side: (i) the mean XV1-GSC was 100° (8°) (median (SD)) versus 106° (3°) on the nonparetic side (p = 0.032, Mann-Whitney); (ii) XV1-GSC diminished with age between ages of 2 and 5 (Spearman, ρ = 0.019); (iii) CCIGM and CCIPL during swing phase were higher than on the nonparetic side (CCIGM, 0.32 (0.20) versus 0.15 (0.09), p < 0.01; CCIPL, 0.52 (0.30) versus 0.24 (0.17), p < 0.01), with an early difference significant for PL from T1 (p = 0.03). CONCLUSIONS: In very young hemiparetic children, the paretic GSC may rapidly shorten in the first years of life. GM and PL cocontraction during swing phase are excessive, which contributes to dynamic equinovalgus. Muscle extensibility (XV1) may have to be monitored and preserved in the first years of life in children with CP. Additional measurements of cocontraction may further help target treatments with botulinum toxin, especially in peroneus longus.

Circumferential minimally invasive approach for low-grade isthmic spondylolisthesis: A clinical and radiological study of 43 patients.

INTRODUCTION: Circumferential fusion for lumbar low-grade isthmic spondylolisthesis (LGIS) provides the best spinal stability and highest fusion rates. The aim of this study is to investigate results of minimal invasive management of LGIS and correlations between Intervertebral Foramen Surface (IFS) and other parameters. METHODS: We retrospectively reviewed cases of 43 patients who underwent a minimally invasive circumferential fusion (Anterior lumbar interbody fusion followed by percutaneous posterior pedicle screw fixation) for LGIS between January 2010 and December 2014 in our institution. Inclusion criteria were one-level (L4-L5 or L5-S1) LGIS with low back and/or radicular pain. Pre- and postoperative radiographic evaluations were performed at 6, 12 and 24months. Measurements (Percentage of anterior displacement, degree of slip angle, height of the intervertebral space and the IFS) were obtained using Surgimap®. RESULTS: Nineteen patients (44.2%) were males. Mean age was 43 years old (19-72years). The mean follow-up of the series was 18.3months (3-72months). Mean preoperative Visual Analogy Scale (VAS) for low back pain decreased from 70mm to 20mm and from 80mm to 10mm as to radicular pain. Anterior displacement was reduced from 18% to 7% (p<0.01), degree of slippage were increased from 9.8° to 15.2° (p<0.01), intervertebral height was restored from 4.4mm to 8.5mm (p<0.01) and increase of the IFS was calculated 48.8%. CONCLUSION: One stage circumferential fixation for adults' LGIS without decompression, allows restoration of intervertebral height permitting good reduction of the slippage, an increasing of the IFS and liberation of nerve roots.

Trends in the surgical management of odontoid fractures in patients above 75 years of age: Retrospective study of 70 cases.

BACKGROUND: Odontoid fractures are the most common upper cervical spine fracture in adults over 70 years of age. Hence, treatment of these fractures has public health implications. OBJECTIVES: Evaluate the early complications, bone healing and mortality in patients above 75 years of age who undergo surgical treatment of an odontoid fracture. Compare the results between patients operated with the Harms technique or anterior screw fixation. METHODS: This was a retrospective study of 70 patients with an odontoid fracture who were treated surgically between 2000 and 2015 at the Hôpital de la Timone in France. The age at the time of diagnosis, comorbidities, ASA score and autonomy were evaluated. Bone healing was determined using computed tomography. RESULTS: In the cohort, 22 patients underwent anterior screw fixation, 38 were treated using the Harms technique and 10 with other procedures. The average age was 85.1 years. Fifty-four percent of patients had an ASA score above 3. The average follow-up was 23.4 months. An Anderson type II fracture was present in 80.6% of patients. In the anterior screw fixation group, the operative time was significantly shorter than in the Harms group and no blood transfusions were needed. However, 13.6% of these patients had to be re-operated because the initial construct was unstable; no patients in the Harms group underwent revision surgery. There were more complications in the anterior screw fixation group than in the Harms group: 41% versus 13.2% (P<0.02). The fractures had healed in all patients reviewed after 1 year. The 3-month survival in the anterior screw fixation group was 64.7% and it was 81.3% in the Harms group. These rates were stable at 1 year with no statistical differences between groups. CONCLUSION: Surgical treatment of odontoid fractures in the elderly results in an excellent union rate. The mortality rate is stable after 3 months. In our experience, the Harms technique has a lower risk of complications and better mechanical stability than anterior screw fixation. Despite the steep learning curve, we believe the Harms technique is probably the best choice for treating odontoid fractures in the elderly. LEVEL OF EVIDENCE: IV.

Operative management of supracondylar humeral fractures in children: Comparison of five fixation methods.

BACKGROUND: The best method for stabilising supracondylar humeral fractures (SHFs) in children remains unclear. The objective of this study was to compare the outcomes of five different fixation methods for SHFs in children. HYPOTHESIS: Differences in intra-operative and short-term post-operative parameters can be demonstrated across different fixation methods for SHFs in children. PATIENTS AND METHODS: We reviewed the medical files of paediatric patients managed at our centre between 2006 and 2016 for SHF with major displacement (type 3 or 4 in the Lagrange-Rigault classification). Clinical and radiological parameters collected post-operatively and at last follow-up included Baumann's angle, anteversion of the distal humeral epiphysis, and operative time. Over the 11-year study period, 251 patients were included; mean age was 6.4 years and mean follow-up 4.7 months. The five fixation methods used were elastic stable intra-medullary nailing (ESIN, n=16), two pins in an X configuration (n=33), two lateral pins and one medial pin (n=144), two lateral pins (n=33), and three lateral pins (n=25). A minimally invasive 2-cm approach was used to insert the medial pins. Immediate instability of the fixation was considered in patients with an at least 15° deficit in Baumann's angle or anteversion, or with rotational malalignment, on the radiographs taken on day 1. Outcomes were analysed in each of the five internal fixation groups. RESULTS: Immediate instability showed no significant differences across the five groups. Operative time was significantly shorter with two lateral pins (33min, P=0.046). Time to hardware removal was longer in the ESIN group (54 days, P=0.03). Use of a medial pin was associated with a lower risk of secondary displacement (2.0% vs. 8.6%, P=0.04) but did not affect the risk of nerve injury (4% vs. 3%, P=0.86). DISCUSSION: This is one of the largest retrospective cohort studies of outcomes according to the fixation technique used to treat SHFs in children. Adding a medial pin through a minimally invasive approach is associated with a longer operative time but limits the risk of secondary displacement without increasing the frequency of iatrogenic nerve injury and improves fracture site stability. Use of a medial pin therefore deserves to be considered in paediatric SHFs. LEVEL OF EVIDENCE: IV, retrospective cohort study.

Evaluation of the external fixator TrueLok Hexapod System for tibial deformity correction in children.

BACKGROUND: Tibial deformities are common in paediatric orthopaedic practice. Correcting multiplanar tibial deformities associated with lower limb length discrepancy can be challenging. Hexapod external fixation with gradual correction has been proven effective in this situation. OBJECTIVE: To assess clinical and radiological outcomes of gradual tibial deformity correction using the external fixator TL-HEX™ (Orthofix) in children. HYPOTHESIS: TL-HEX™ is effective in correcting tibial deformities in children. PATIENTS AND METHODS: This multicentre retrospective study collected data from the medical files of 26 patients with 31 tibial deformities treated by gradual correction using TL-HEX™. The tibial deformities were due to congenital defects in 11 (35%) cases, Blount's disease in 9 (29%) cases, pseudo-achondroplasia in 4 (13%) cases, and other causes in 7 (23%) cases. Mean age at surgery was 11.9 years. In each patient, antero-posterior long leg radiographs obtained pre-operatively and at last follow-up were used to measure parameters including the mechanical axis deviation (MAD), medial proximal tibia angle (MPTA), and leg length discrepancy (LLD). RESULTS: The mean healing index was 39.3 days/cm (range, 32-58 days/cm). The overall complication rate was 61%, with 11 unplanned visits. Superficial pin tract infection was the most common complication. Significant decreases between the pre-operative and post-operative assessments occurred in mean MAD (from 32.1mm to 10.2mm, P<0.001) and mean LLD (from 36.8mm to 9.1mm, P<0.001). Patients who underwent proximal tibial osteotomy had a significant improvement in MPTA, from 80.6° to 88.5° (P=0.006). DISCUSSION: This is the first clinical study specifically designed to assess outcomes of TL-HEX™ limb lengthening and deformity correction. MAD, MPTA, and LLD were significantly improved at last follow-up. MAD was greater than 10mm at last follow-up in only 11patients. The complication rate was similar to those reported with other external fixators. TL-HEX™ is effective in the management of tibial deformities in children. LEVEL OF EVIDENCE: IV (retrospective study).

Correction of axial deformity during lengthening in fibular hypoplasia: Hexapodal versus monorail external fixation.

INTRODUCTION: Childhood fibular hypoplasia is a rare pathology which may or may not involve limb-length discrepancy and axial deformity in one or more dimensions. The objective of the present study was to compare the quality of the axial correction achieved in lengthening procedures by hexapodal versus monorail external fixators. The hypothesis was that the hexapodal fixator provides more precise correction. MATERIAL AND METHODS: A retrospective multicenter study included 52 children with fibular hypoplasia. Seventy-two tibias were analyzed, in 2 groups: 52 using a hexapodal fixator, and 20 using a monorail fixator. Mean age was 10.2 years. Mean lengthening was 5.7cm. Deformities were analyzed and measured in 3 dimensions and classified in 4 preoperative types and 4 post-lengthening types according to residual deformity. RESULTS: Complete correction was achieved in 26 tibias in the hexapodal group (50%) and 2 tibias in the monorail group (10%). Mean post-correction mechanical axis deviation was smaller in the hexapodal group: 12.83mm, versus 14.29mm in the monorail group. Mean post-correction mechanical lateral distal femoral angle was 87.5° in the hexapodal group, versus 84.3° in the monorail group (P=0.002), and mean mechanical medial proximal tibial angle 86.9° versus 89.5°, respectively (P=0.015). DISCUSSION: No previous studies focused on this congenital pathology in lengthening and axial correction programs for childhood lower-limb deformity. The present study found the hexapodal fixator to be more effective in conserving or restoring mechanical axes during progressive bone lengthening for fibular hypoplasia. CONCLUSION: The hexapodal fixator met the requirements of limb-length equalization in childhood congenital lower-limb hypoplasia, providing better axial correction than the monorail fixator. LEVEL OF EVIDENCE: IV.

Intraoperative spinal cord monitoring: Lesional level diagnosis.

BACKGROUND: In spinal deformity surgery, iatrogenic spinal cord injury is the most feared complication. Intraoperative monitoring (IOM) of the spinal cord assesses its functional integrity and allows significant reduction of the rate of spinal cord injury. HYPOTHESIS: In case of severe IOM alert, lesional level diagnosis constitutes supplementary and useful information. MATERIAL AND METHODS: This study was retrospective and monocentric. In our institution, 1062 pediatric spinal deformity surgeries have been monitored since 2004. We review the records of the six patients who presented a severe and prolonged IOM alert with lesional level determination. Somatosensory evoked potentials (SSEP), neurogenic mixed evoked potentials (NMEP) and D-waves were performed. In cases of IOM alert, sequentially moving an epidural electrode along the spinal cord allows lesional level determination, using this electrode either for stimulation or recording. RESULTS: Six patients, aged 12 to 17 years, characterized by severe IOM alerts during spinal deformity surgery are reported. Postoperative neurological examination was normal for five out of six cases. For patient 2, lesional level diagnosis allowed to determine a bi-laminar claw between T2 and T3 as the etiology of IOM alert. This IOM alert was delayed in time, being detectable only 30minutes after the placement of this claw. Postoperative neurological examination was normal. For patient 6, a Stagnara wake-up test demonstrated paraplegia. Lesional level was established. Following corrective surgical maneuvers, postoperative neurologic deficit was limited to a pyramidal syndrome in one lower limb. Postoperative MRI demonstrated a spinal cord lesion at the determined lesional level. CONCLUSION: During an IOM alert, lesional level determination allows localization of spinal cord dysfunction. This data, obtainable whatever the IOM device, constitutes supplementary information in order to rapidly identify the etiology of IOM alert and thus to react in the most appropriate way. LEVEL OF EVIDENCE: IV, retrospective study.

Surgical management of post-traumatic atlantoaxial rotatory fixation due to C2 facet fracture: 5 clinical cases.

PURPOSE: Report the results of surgical treatment of post-traumatic atlantoaxial rotatory fixation (AARF) due to C2 articular facet fracture in adults. MATERIAL AND METHODS: The records of five patients treated since 2009 for AARF due to a C2 articular facet fracture were analyzed retrospectively. Three women and two men with an average age of 60 years (27-82) were included, one of whom initially had neurological deficits. In all cases, the surgical strategy consisted of posterior fixation: Harms-type in four cases and trans-articular with hooks in one case. RESULTS: Dislocations due to fracture of the C2 articular facet are rare in adults; various treatment strategies have been described. In our experience, posterior screw fixation leads to satisfactory clinical and radiological outcomes. Fusion is not necessary in these cases because the dislocation is related to an asymmetric fracture without ligament damage. CONCLUSION: Posterior fixation provides satisfactory reduction of these injuries and leads to satisfactory bone union. This surgical treatment can be performed early on after the trauma and is an interesting alternative to conservative treatment.

Impact of surgical correction of a U-shaped sacral fracture on sagittal spino-pelvic alignment: Regarding one case.

U-shaped sacral fractures are uncommon and are mostly the consequence of a high-energy kinetic trauma. The sacrum is a crucial element for sagittal alignment in a standing position as it determines the value of the pelvic incidence, which is a fixed and unchanging parameter for a given individual. We report the case of a 21-year-old man who underwent corrective surgery for a type II U-shaped fracture of the sacrum (according to the Roy-Camille classification), associated with a S1-S2 dislocation and sacral kyphosis that modified the patient's pelvic incidence. At one-year follow-up, radiographic examinations revealed solid bony fusion and stable results after removal of the implants. The surgery was managed for neurological decompression, stabilization of the fracture and correction of sacral kyphosis. The restoration of the theoretical pelvic incidence depended on the estimated lumbar lordosis. The aim of this study was to highlight the particularities in the management of a sacral U-shaped fracture and their relationship with the sagittal alignment.

Transplantar intramedullary locking nailing in childhood congenital pseudarthrosis of the tibia: A report of 3 cases.

The treatment objectives in congenital pseudarthrosis of the tibia are bone consolidation and a restored lower-limb axis. They are difficult to achieve, and various surgical techniques have been described, with varying results in terms of bone consolidation and complications. The present study reports clinical and radiographic results in 3 patients managed by the same original technique of transplantar intramedullary nailing using a custom-made proximal locking nail, without surgical approach or resection of the pseudarthrosis site. Good assembly stability allowed immediate weight-bearing. The technique is relatively noninvasive, offering a first-line alternative in under-3 year-olds.

[Giant recurrent trochanteric pressure sore: A complex medico-surgical care]. / Escarre trochantérienne géante récidivante : une prise en charge médico-chirurgicale complexe.

BACKGROUND: Pressure sores are a frequent complication in spinal injured people. Their treatment is often long and complex. OBSERVATION: We report the case of a 60-year-old man affected with complete paraplegia who developed a right trochanteric pressure ulcer complicated with osteoarthritis of the coxofemoral joint. The treatment was done in three steps. First, a large excision of necrotic tissues and a femoral head-neck resection is performed. Then, the defect is partly covered with a Gluteus Maximus and a Biceps Femoris myocutaneous flaps. Finally, the residual defect is covered with a cutaneous pedicled groin flap called McGregor's flap. Later, the patient showed a right para-scrotal pressure sore on a heterotopic ossification of the ischial tuberosity. DISCUSSION: McGregor's flap is rarely employed for treating trochanteric pressure sores. It was here the only pedicled flap available. It was necessary to autonomize it in order to get enough length and to place a hip external fixation. The para-scrotal pressure sore illustrates the fact that bone resection surgery lifts the weight-bearing zones and can lead to pressure sores in unusual locations. CONCLUSION: The surgical treatment of these "giant" pressure sores requires a perfect collaboration between teams of rehabilitation and several surgical areas. Without a good adherence of the patient, the treatment is doomed to fail.

[Use of pedicle percutaneous cemented screws in the management of patients with poor bone stock]. / Utilisation de vis cimentées percutanées dans la prise en charge rachidienne des patients à faible capacité osseuse.

INTRODUCTION: Management of patients with poor bone stock remains difficult due to the risks of mechanical complications such as screws pullouts. At the same time, development of minimal invasive spinal techniques using a percutaneous approach is greatly adapted to these fragile patients with a reduction in operative time and complications. The aim of this study was to report our experience with cemented percutaneous screws in the management of patients with a poor bone stock. METHODS: Thirty-five patients were included in this retrospective study. In each case, a percutaneous osteosynthesis using cemented screws was performed. Indications were osteoporotic fractures, metastasis or fractures on ankylosing spine. Depending on radiologic findings, short or long constructs (2 levels above and below) were performed and an anterior column support (kyphoplasty or anterior approach) was added. Evaluation of patients was based on pre and postoperative CT-scans associated with clinical follow-up with a minimum of 6 months. RESULTS: Eleven men and 24 women with a mean age of 73 years [60-87] were included in the study. Surgical indication was related to an osteoporotic fracture in 20 cases, a metastasis in 13 cases and a fracture on ankylosing spine in the last 2 cases. Most of the fractures were located between T10 and L2 and a long construct was performed in 22 cases. Percutaneous kyphoplasty was added in 24 cases and a complementary anterior approach in 3 cases. Average operative time was 86minutes [61-110] and blood loss was estimated as minor in all the cases. In the entire series, average volume of cement injected was 1.8 cc/screw. One patient underwent a major complication with a vascular leakage responsible for a cement pulmonary embolism. With a 9 months average follow-up [6-20], no cases of infection or mechanical complication was reported. CONCLUSION: Minimal invasive spinal techniques are greatly adapted to the management of fragile patients. The use of percutaneous cemented screws is, in our experience, a valuable alternative for spinal fixation in patients with poor bone stock. This technique allows a good bony fixation with a low rate of complications. However, rigorous preoperative planning is necessary in order to avoid complications.

Interest of T1 parameters for sagittal alignment evaluation of adolescent idiopathic scoliosis patients.

PURPOSE: In the last few years several reports stressed the importance of sagittal alignment in adolescent idiopathic scoliosis (AIS) patients. It was recently reported that T1 slope, defined as the angle between the superior endplate of T1 and the horizontal, correlates strongly with overall sagittal parameters. The aim of this study was to assess the impact of T1 parameters (T1-slope and T1-tilt) on sagittal alignment of AIS hypokyphotic patients preoperatively and postoperatively. METHODS: Twenty-nine AIS patients with <20° preoperative hypokyphosis were included in a retrospective study. Surgery systematically comprised hybrid construct with screws below T11, sublaminar bands at thoracic level and a lamino-laminar claw on the upper instrumented vertebra. Preoperative, postoperative and 2-year follow-up radiological assessment included Cobb angle, T1 slope, T1 sagittal tilt, regional sagittal parameters and pelvic parameters. RESULTS: In the series as a whole, coronal Cobb angle was significantly reduced postoperatively (58° vs. 17°; p < 0.001), thoracic kyphosis significantly improved (12.4° vs. 25.6°; p < 0.001) and cervical lordosis significantly restored (6.2° kyphosis vs. 4.1° lordosis; p < 0.001). There was a significant modification in T1-slope (10.2° vs. 18.2°; p < 0.001). Preoperatively, T1 slope was significantly correlated with T1 tilt (r = 0.427; p = 0.029). Postoperatively, T1 slope was significantly correlated with T1 tilt (r = 0.549; p = 0.002), thoracic kyphosis (r = 0.535, p = 0.005) and cervical lordosis (r = -0.444, p = 0.03). Restoration of cervical lordosis was significantly correlated to changes of T1-slope (r = -0.393, p = 0.032), which was significantly correlated to postoperative thoracic kyphosis. CONCLUSION: According to these results, T1 seems to be of major interest in postoperative modifications of sagittal alignment. T1 slope and sagittal tilt are good indicators of postoperative changes for regional (cervical lordosis and thoracic kyphosis) and global parameters. We therefore consider these parameters as essential in the assessment of AIS patients. Further studies and correlation with clinical scores will, however, be necessary in order to confirm the present findings.

Minimal Invasive Circumferential Management of Thoracolumbar Spine Fractures.

INTRODUCTION: While thoracolumbar fractures are common lesions, no strong consensus is available at the moment. OBJECTIVES: The aim of this study was to evaluate the results of a minimal invasive strategy using percutaneous instrumentation and anterior approach in the management of thoracolumbar unstable fractures. METHODS: 39 patients were included in this retrospective study. Radiologic evaluation was based on vertebral and regional kyphosis, vertebral body height restoration, and fusion rate. Clinical evaluation was based on Visual Analogic Score (VAS). All evaluations were done preoperatively and at 1-year follow-up. RESULTS: Both vertebral and regional kyphoses were significantly improved on postoperative evaluation (13° and 7° versus -1° and -9° P < 0.05, resp.) as well as vertebral body height (0.92 versus 1.16, P < 0.05). At 1-year follow-up, mean loss of correction was 1°. A solid fusion was visible in all the cases, and mean VAS was significantly reduced form 8/10 preoperatively to 1/10 at the last follow-up. CONCLUSION: Management of thoracolumbar fractures using percutaneous osteosynthesis and minimal invasive anterior approach (telescopic vertebral body prosthesis) is a valuable strategy. Results of this strategy offer satisfactory and stable results in time.