Improvements in Pediatric Bone Loss Reconstruction With the Induced Membrane Technique.

BACKGROUND: The induced membrane technique is now widely used for pediatric diaphyseal bone loss due to various etiologies. Although consolidation rates remain satisfactory, complications, and healing delays may occur requiring additional procedures. We studied a series of induced membrane bone reconstructions in which the second stage included an embedded endomembranous non vascularized fibular shaft, in addition to iliac bone grafts. The purpose of this study was to analyze the results in terms of bone consolidation and complications. METHODS: This is a retrospective comparative and multicentric study of 32 children with large bone loss treated with the induced membrane reconstruction technique. Patients were divided into 2 groups according to the graft used during the second stage. The first group (G1) of 16 patients had a nonvascularized fibula embedded inside the membrane in addition with the corticocancellous grafts from the iliac crest. The second group (G2) of 16 patients underwent reconstruction using the original technique, with iliac crest graft only. RESULTS: The 2 groups were similar in terms of etiologies of bone loss and follow-up (mean: 44 mo for G1 and 49 mo for G2). Mean bone losses were 15.4 cm (range: 2 to 25; SD: 5.6) for G1 and 10.6 cm (range: 3 to 19; SD: 5.2) for G2. In the first group, all patients healed primarily, with a mean time of 5.9 months (range: 4 to 8; SD: 1.6). In the second group, 2 of 16 patients did not healed; for the others 14, healing mean time was 6.9 months (range: 3 to 12; SD: 2.7). The short-term and long-term complications rates were 38% to 19% for G1 and 50% to 31% for G2, respectively. Regarding the donor site, the fibulas reconstructed spontaneously with a mean time of 4.8 months (range: 3 to 6; SD: 1.2). CONCLUSIONS: The integration of a nonvascularized fibula during the second stage of the induced membrane technique appears to improve the consolidation rate in the pediatric population. LEVEL OF EVIDENCE: Level III-Retrospective comparative study.

Is posterior vertebral arthrodesis at the end of the electromagnetic rod lengthening program necessary for all patients? Comparative analysis of sixty six patients who underwent definitive spinal arthrodesis and twenty four patients with in situ lengthening rods.

PURPOSE: Magnetically controlled growing rods (MCGR) should be removed or changed at most two years after their implantation in the treatment of patients with early-onset scoliosis (EOS) (Safety notice July 2021). However, in the face of patients at high risk of intraoperative complications and relying on the principle of auto-fusion of the spine, some surgeons would prefer a more wait-and-see attitude. The aim of this study was to report on patients who did not undergo final fusion at the end of the lengthening program with MCGR and to compare them with those who did. METHODS: This was a multicenter study with ten centres. We collected all graduate patients with EOS who had received MCGR between 2011 and 2022. RESULTS: A total of 66 patients had final fusion at the end of the lengthening program and 24 patients kept MCGRs in situ. The mean total follow-up time was 66 months (range, 25.3-109), and the mean follow-up time after final lengthening was 24.9 months (range, 3-67.7). Regarding the main curve and thoracic height, there was no significant difference in the percentage of correction over the whole follow-up between the two groups (p = 0.099, p = 0.176) although there was a significant difference between the end of lengthening and the last follow-up (p < 0.001). After completion of the lengthening program, 18 patients who had final fusion developed 24 of the 26 recorded complications (92.3%). CONCLUSION: Contrary to the manufacturer's published safety notice, not all patients systematically benefited from the removal of the MCGRs. Although arthrodesis significantly improved the scoliotic deformity, no significant difference was found in terms of radiographic outcome between patients who underwent spinal fusion and those who kept the MCGRs in situ.

Clinical and radiological results of final fusion in patients who underwent lengthening with magnetically controlled growing rods. About 66 patients with a mean follow-up of 5 years.

PURPOSE: The aim of this study was to evaluate the effects of definitive arthrodesis on frontal and sagittal spine balance in EOS patients treated with MCGR, as well as the complications associated with this procedure and the outcome at last follow-up. METHODS: This was a multicentre study in 10 French centres. All patients who underwent posterior spinal arthrodesis after completion of MCGR treatment, regardless of age, etiology of scoliosis between 2011 and 2022, were included. RESULTS: A total of 66 patients who had a final fusion after the lengthening programme were included in the study. The mean follow-up time was 5.5 ± 1.7 years (range: 2.1-9). The mean follow-up time after arthrodesis was 24 ± 18 months (range: 3-68) and the mean age at arthrodesis was 13.5 ± 1.5 years (range: 9.5-17). The main and secondary curves were significantly (p < 0.005 and p = 0.03) improved by arthrodesis (16.4° and 9° respectively) and stabilised at the last follow-up. The T1-T12 and T1-S1 distances increased by 8.4 mm and 14 mm with spinal fusion, with no significant difference (p = 0.096 and p = 0.068). There was no significant improvement in the rest of the parameters with arthrodesis, nor was there any significant deterioration at last follow-up. After final fusion, there were a total of 24 complications in 18 patients (27.3%) that routinely led to repeat surgery. CONCLUSION: Final fusion after MCGR provides satisfactory additional correction of the main and secondary curves and a moderate increase in the T1-T12 distance but has no impact on sagittal balance and other radiological parameters. The post-operative complication rate is particularly high in patients at risk of complications. LEVEL OF EVIDENCE: Level 4.

Clinical and radiographic evolution of graduate patients treated with magnetically controlled growing rods: results of a French multicentre study of 90 patients.

PURPOSE: The purpose of this study was to investigate patients with early-onset scoliosis (EOS) who completed their electromagnetic lengthening rod program to assess the demographics of this population and to analyze the evolution of clinical and radiological parameters and the occurrence of complications. METHODS: This was a multicenter study with 10 French centers. We collected all patients with EOS who had undergone electromagnetic lengthening between 2011 and 2022. They had to have reached the end of the procedure (graduate). RESULTS: A total of 90 graduate patients were included. The mean follow-up time over the entire period was 66 months (25.3-109). Of these, only 66 patients (73.3%) underwent definitive spinal arthrodesis at the end of the lengthening phase, whereas 24 patients (26.7%) kept their hardware in situ with a mean follow-up time from the last lengthening of 25 months (3-68). Patients had an average of 2.6 surgeries (1-5) over the entire follow-up. Patients had an average of 7.9 lengthenings for a mean total lengthening of 26.9 mm (4-75). Analysis of the radiological parameters showed a percentage reduction in the main curve of 12 to 40%, depending on the etiology, with an average reduction of 73-44°, and an average thoracic height of 210 mm (171-214) for an average improvement of 31 mm (23-43). There was no significant difference in the sagittal parameters. During the lengthening phase, there were a total of 56 complications in 43 patients (43.9%; n = 56/98), of which 39 in 28 patients (28.6%) resulted in unplanned surgery. In the graduate patients, there were a total of 26 complications in 20 patients (22.2%), all of which resulted in unscheduled surgery. CONCLUSION: MCGR, allow to decrease the number of surgeries, to progressively improve the scoliotic deformity and to reach a satisfactory thoracic height at the price of an important complication rate linked in particular to the complexity of the management of patients with an EOS.

Does the induced membrane have antibacterial properties? An experimental rat model of a chronic infected nonunion.

INTRODUCTION: The Masquelet procedure proved its efficiency in treating infected nonunion filling bony gaps up to 25 cm. Yet the use of local antibiotics is still questionable in the daily practice with lack of evidence regarding its usefulness in controlling infection. An experimental rat model is put in place to study the antibacterial properties of the induced membrane produced during the first stage of Masquelet. METHOD: Twenty-three-month-old wistar male rats are inoculated with a 0.5 mL solution of 10^8 CFU/mL MRSA over a critical fracture done on the right femur. Six weeks later, remaining 11 rats exhibiting signs of a chronic infection with a sinus tract and oozing pus along with radiological nonunion are used for a first stage Masquelet procedure. They are randomly divided into two groups with six rats having no local antibiotic in the cement mixture and five rats having 3 g of vancomycin mixed with gentamycin loaded cement. Six weeks later (twelve weeks from baseline), all eleven rats are euthanized and blood samples for C-reactive protein are withdrawn. The induced membrane is identified and resected along with bone fragments and sent for cultures and pathology. RESULTS: MRSA is isolated in the cultures of all six rats in the first group where no local antibiotic was added. Altered polymorphonuclears with abscess and pus are noted on four of six pathology samples. However in the second group where local antibiotics were added, three out of five rats exhibited eradication of MRSA (p = 0.034) and all samples did not exhibit clear infection signs on pathology. A pyo-epithelioid over a foreign body reaction is seen predominantly in this group demonstrating a regenerative process. DISCUSSION: The induced membrane does not have antimicrobial properties capable of overcoming an infected nonunion on its own. When local antibiotics were added during the first stage of the Masquelet procedure, new bone formation occurred indicating the need to control an infection in order for bone union to occur. CONCLUSION: Local antibiotics use in adjunction to extensive debridement is advisable during the first stage of a Masquelet procedure for an infected nonunion.

The chemokine CCL20 induces proinflammatory and matrix degradative responses in cartilage.

INTRODUCTION: Local inflammation plays a role in the pathophysiology of osteoarthritis (OA) and chemokines exert catabolic effects on articular cartilage either through paracrine and/or autocrine mechanisms. We sought to compare the expression levels of the chemokine (C-C motif) ligand 20 (CCL20) and its chemokine receptor 6 (CCR6) in donor and osteoarthritic (OA) cartilage and to investigate the role of CCL20 in the pathogenesis of OA and chondrocyte phenotype. METHODS: Cartilage/chondrocytes from donor and OA knee joints was analyzed for CCL20 and CCR6 expression by RT-PCR and immunohistochemistry. Effects of CCL20 on cytokines and mediators of cartilage degradation were examined by RT-PCR for mRNA expression levels, enzyme-linked immunosorbent assays, and proteoglycan (GAG) assays. RESULTS: CCL20 and CCR6 proteins were abundantly expressed in OA cartilage sections compared to donor sections as judged by immunohistochemistry. RT-PCR of cartilage extracts confirmed the predominance of CCL20/CCR6 mRNA expression in OA cartilage. CCL20 mRNA expression was low in donor chondrocytes but increased after stimulation with proinflammatory cytokines. mRNA expression levels of IL-6, cyclooxygenase-2, and iNOS were elevated in donor chondrocyte cultures treated with rhCCL20. The release of MMP1/13, PGE2, proteoglycan GAG fragments, and IL-6 from cartilage explant cultures was markedly augmented in the presence of CCL-20. CCL-20 stimulated MMP-13, ADAMTS-5, and col type X mRNA but inhibited col type II mRNA expression in freshly explanted and cultured cartilage specimens. CONCLUSIONS: CCL20/CCR6 may play an important role in the pathogenesis of OA by inducing changes in phenotype and catabolic gene expression in chondrocytes.

Roussouly's sagittal spino-pelvic morphotypes as determinants of gait in asymptomatic adult subjects.

Sagittal alignment is known to greatly vary between asymptomatic adult subjects; however, there are no studies on the possible effect of these differences on gait. The aim of this study is to investigate whether asymptomatic adults with different Roussouly sagittal alignment morphotypes walk differently. Ninety-one asymptomatic young adults (46M & 45W), aged 21.6±2.2years underwent 3D gait analysis and full body biplanar X-rays with three-dimensional (3D) reconstructions of their spines and pelvises and generation of sagittal alignment parameters. Subjects were divided according to Roussouly's sagittal alignment classification. Sagittal alignment and kinematic parameters were compared between Roussouly types. 17 subjects were classified as type 2, 47 as type 3, 26 as type 4 but only 1 as type 1. Type 2 subjects had significantly more mean pelvic retroversion (less mean pelvic tilt) during gait compared to type 3 and 4 subjects (type 2: 8.2°; type 3:11.2°, type 4: 11.3°) and significantly larger ROM pelvic obliquity compared to type 4 subjects (type 2: 11.0°; type 4: 9.1°). Type 2 subjects also had significantly larger maximal hip extension during stance compared to subjects of types 3 and 4 (type 2: -11.9°; type 3: -8.8°; type 4: -7.9°) and a larger ROM of ankle plantar/dorsiflexion compared to type 4 subjects (type 2: 31.1°; type 4: 27.9°). Subjects with type 2 sagittal alignment were shown to have a gait pattern involving both increased hip extension and pelvic retroversion which could predispose to posterior femoroacetabular impingement and consequently osteoarthritis.

Proximal subscapularis release for the treatment of adduction-internal rotation shoulder contracture in obstetric brachial plexus palsy.

INTRODUCTION: The purpose of this paper was to evaluate the results on shoulder function following isolated proximal subscapularis release in children with Erb's palsy. METHODS: A retrospective study was conducted on 64 consecutive children with Erb's palsy who underwent a Carlioz proximal subscapularis release between 2001 and 2012. Fifty children with complete records and a minimum follow-up of 2 years were included for evaluation. Age at surgery ranged from 1.3 to 4.5 years (average 2.6 years). Preoperative active shoulder abduction/anterior elevation, active external and internal rotations as well as the Mallet score were compared with those found at 6 and 24 months postoperatively using the Student paired t test, with a confidence interval of 95 %. The results were compared between children <3 years of age at surgery and those older, and between children who had an isolated C5-C6 and those with greater involvement. p < 0.05 was considered statistically significant. RESULTS: Active abduction improved 21° at 6 months and 31° (total) at 2 years (p < 0.01) with an overall Mallet abduction score improvement of 0.58 at 6 months and 0.6 (overall) at 2 years (p < 0.01). Active external rotation improved 52° at 6 months and 35° (total) at 2 years (p < 0.01) with an overall Mallet external rotation score improvement of 1.3 at 6 months (p < 0.01) and 0.52 (overall) at 2 years (p = 0.013). There was no statistically significant change in internal rotation (p = 0.37). We found no correlation between the child's age or the severity of involvement at surgery and the end result. CONCLUSION: Proximal subscapularis release according to Carlioz is simple and effective in improving overall shoulder function in children with obstetric brachial plexus palsy, mainly abduction and external rotation. Improvement tends to reach a plateau around 6-12 months postoperatively.