Induced-Membrane Reconstruction After Calcaneum's Ewing Sarcoma in Children: A Report of 3 Cases.

Calcaneus's Ewing sarcoma is a rare location with a poor prognosis and remains challenging for tumor surgery. We present 3 cases of calcaneus resection for Ewing sarcoma in children and its reconstruction managed by induced-membrane technique. To our knowledge, this technique has never been published for hindfoot's tumor management. Three children (aged from 9 to 14 years) had partial or total resection of calcaneus initially replaced by a cement spacer. The second step consisted of removing the cement and filling the membrane cavity with autograft taken from the ipsilateral iliac crest, potentially combined with bone substitute. In the meantime, children received chemotherapy and possibly radiotherapy according to the Euro E.W.I.N.G. 99 protocol. It was possible to optimize bone formation as we carried out the bone grafting procedure sometime after the treatments. In one case, the evolution was marked by local septic complication, 9 months after resection, and by tumor recurrence in presacral soft tissues treated with radiotherapy and chemotherapy. Partial weightbearing was allowed after 6 weeks of cast, under the protection of a splint. Graft consolidation was achieved at a median of 3.2 months (3-3.5) for all. After a median follow-up of 9 years (5-13), all preserved their limb and were considered in remission. The 3 children reached adulthood, with a median age of 21 years (19-24.8). At last follow-up, median Musculoskeletal Tumor Score was 73% (63-87), and median American Orthopaedic Foot and Ankle Society hind foot score was 78 (72-87).

Osteonecrosis of the Femoral Head: A Proposed New Treatment in Homozygous Sickle Cell Disease.

UNLABELLED: Possibilities for bone reconstruction in osteonecrosis of the femoral head in sickle cell hemoglobinopathies before the end of growth have not been assessed. The aim of our study was to evaluate the morphological and functional results in 11 osteonecrosis of the femoral head because of homozygous sickle cell disease. Surgical treatment consisted of a triple acetabular osteotomy in seven cases, femoral varus osteotomy in two cases and a combination of both in two cases. The severity of the osteonecrosis was evaluated on radiographs and magnetic resonance imaging (MRI), pre- and postoperative, and function of the hip joint was assessed by Harris and Postel Merle d'Aubigné scores. The anesthetic part (pre- and postoperative) and eventual complications were collected and analyzed. The maximum follow-up was between 1 to 9.6 years. All patients were considered to be satisfactory at maximum follow-up. The severity of the initial damage was not associated with any morphological or functional outcome at maximum follow-up. All patients had an objective functional gain. We found no general complications. We proposed a decision tree for the patient's management of avascular necrosis of the femoral head in sickle cell hemoglobinopathies before bone maturity, and with an Arlet and Ficat's stage of 3 or 4. The results of this study confirmed the interest of conservative surgical treatment in children with homozygous sickle cell anemia in case of osteonecrosis of the femoral head. LEVEL OF EVIDENCE: IV (cases series of our department).

Synovial sarcoma in children and adolescents.

Synovial sarcoma (SS) is a high-grade soft tissue sarcoma characterized by local invasiveness and a propensity to metastasize, affecting pediatric, adolescent, and adult populations. The peak incidence is observed in the third decade of life and SS is the most common nonrhabdomyosarcoma soft tissue sarcoma in childhood and adolescence. Although pediatric and adult SS appear clinically and radiologically identical, treatment modalities may differ according to the patient's age. For many years, pediatric oncologists have treated SS as a chemosensitive tumor according to the "rhabdomyosarcoma philosophy." In contrast, adult oncologists generally treat this tumor as a poorly chemosensitive tumor and focus on local control. The authors propose an update of SS in the pediatric population and analyze their results to those obtained in adults.

High-grade lumbosacral spondylolisthesis reduction and fusion in children using transsacral rod fixation.

PURPOSE: There is no consensus on how to treat surgically high-dysplastic developmental spondylolisthesis in children and adolescents. Although reducing spinal deformity seems mandatory, the issue of surgical reduction versus in situ fusion remains controversial. METHODS: The files of 12 consecutive patients surgically treated for a grade 3 or 4 spondylolisthesis were reviewed. The treatment consisted in L4 to sacrum reduction and fusion by posterior approach. The reduction of lumbopelvic imbalance was made intraoperatively using a trans-sacral rod fixation technique. RESULTS: Mean preoperative L5 anterior slippage was 72.3 % (60 to 95 %). The mean preoperative lumbosacral tilt angle was 70.5° (43 to 92°). Mean final lumbosacral tilt angle was 102° (91 to 114°). Mean final L5 anterior slippage was 19 % (7 to 63 %). Neurological complications (radicular L5 or S1 deficits) were noted in five patients. At final follow-up L4 to S1 fusion was achieved in all patients. No patient had persistent deficit or radicular pain. CONCLUSIONS: The fusion rate in our series proved to be optimal. Thanks to the trans-sacral rod fixation, lumbosacral kyphosis correction was very good. The intrasacral positioning of the screws reduces the risk of implant prominence especially in such pediatric patients. We stress the importance to avoid complete slip reduction in such patients to minimize stretching on L5 and S1 roots. No additional immobilization is needed due to solid posterior instrumentation. Doing such procedure only by posterior approach avoids anterior approach-related complications.

CoCr rods provide better frontal correction of adolescent idiopathic scoliosis treated by all-pedicle screw fixation.

PURPOSE: Pedicle screw fixation is considered biomechanically advantageous in adolescent idiopathic scoliosis (AIS) correction, because it uses as an anchor the pedicle, which is the hardest part of the vertebral body. The ability of the rod to correct and hold the correction is a key factor in the selection of rod material. The goal of this study was to compare the results obtained by stainless steel (SS) and cobalt-chromium (CoCr) rods materials for the treatment of AIS curves. METHODS: Ninety patients were retrospectively included. Sixty-four patients (group 1) were operated on using CoCr rods. Twenty-six patients (group 2) were operated on using SS rods. All the patients were treated by the same surgeon using all-pedicle screw constructs. RESULTS: In group 1, the correction was respectively 41.03° and 35.78° for main and secondary curves. In group 2, the correction was respectively 30.98° and 24.42° for main and secondary curves. Statistical analysis showed improved correction rates in patients operated with CoCr rods for main (P < 0.0001) and secondary (P = 0.0003) curves with a lower loss of correction at final follow-up. Regarding the sagittal profile, postoperative T4T12 thoracic kyphosis was 28.04° in CoCr group compared to 22.79° in SS group (P = 0. 0.0038). DISCUSSION: The present study confirms the ability of the all-pedicle screw construct to reach the maximum coronal plane correction and prevent deformity progression while maintaining balance. CoCr rods have the ability to exert higher corrective forces on the spine with relatively small amounts of rod deformation. Our findings confirm that CoCr rods have the ability to produce higher correction rates in frontal plane compared to SS rods of the same diameter.

Correction of pelvic obliquity in neuromuscular spinal deformities using the "T construct": results and complications in a prospective series of 60 patients.

BACKGROUND: We present the results of a prospective series of 60 patients treated for neuromuscular spinal deformities with an original spinopelvic construct using two sacral screws and two iliac screws. Clinical and radiological results obtained with this new surgical technique were studied and discussed according to the epidemiological data and relevant literature. METHODS: From January 2008 to June 2010, the clinical data of every patient who underwent spinopelvic fixation for treatment of a neuromuscular spinal deformity were recorded prospectively. RESULTS: Sixty patients were operated on during the study period. Spinal correction and fusion was performed by posterior approach. In six patients with a residual spinopelvic imbalance more than 15° on lateral preoperative bending films, an anterior release of the thoracolumbar junction was performed on the same day, before posterior correction. Preoperative pelvic obliquity (PO) ranged from 4° to 44° (mean 21.6°). Postoperative pelvic obliquity ranged from 0° to 14 (mean 4.6°). No significant loss of correction was noted at the last follow-up. One patient died 3 months after the initial procedure due to respiratory compromise. 11 patients had early postoperative infections of the posterior approach. CONCLUSIONS: Despite a high rate of infectious complications, optimal correction of pelvic obliquity requires extension of spinal instrumentation to the pelvis. Spinopelvic fixation remains a difficult challenge in neurological patients with hypotrophy. We think that pelvic fixation with the "T construct" did provide effective and improved spinal stabilization in these patients, while reducing the need for a postoperative cast or brace. As a result, patients had a favourable postoperative course with early mobilization and return to a comfortable sitting position.

Induced-membrane technique for lower limb reconstruction after malignant bone tumour resection in paediatric patients: Complication and re-operation rates.

BACKGROUND: The objective of this study was to assess the complication and re-operation rates, evaluate the risk of non-union, and describe the functional outcomes at last follow-up in children and adolescents after lower-limb malignant tumour resection and reconstruction using the induced-membrane technique. HYPOTHESIS: Weight-bearing resumption 6 weeks after the second stage of the induced-membrane procedure promotes bone healing. MATERIAL AND METHODS: The study included 13 patients (9 with osteosarcoma, 3 with Ewing's sarcomas, and 1 with alveolar sarcoma) managed between 2000 and 2020 by oncological femoral or tibial resection followed, at a distance from adjuvant chemotherapy, by reconstruction using the induced-membrane technique. Non-union was the primary outcome measure and the MusculoSkeletal Tumor Society (MSTS) lower-limb functional score was the secondary outcome measure. Mean follow-up was 6.1 years (range, 2.0-12.7). At last follow-up, mean age was 18.1 years (range, 11.0-26.0) and the mean MSTS score was 66.6% (37.0-93.0%). RESULTS: After the second reconstruction stage, 8 complications developed in 6 patients (46%). Either a complication or limb-length inequality required 12 re-operations in 8 patients (61.5%). Non-union occurred after reconstruction in 5 (38.5%) patients. Early resumption of 50% weight-bearing 6 weeks after reconstruction was associated with bone healing (p=0.02). CONCLUSION: The non-union rate was 38.5%. Partial, 50% weight-bearing with two elbow crutches and an orthosis, if allowed by construct stability, may promote bone healing. LEVEL OF EVIDENCE: IV.

Desmoid fibromatosis in pediatric patients: management based on a retrospective analysis of 59 patients and a review of the literature.

Background. Only limited data are available concerning desmoid tumor in children. Methods. Fifty-nine children and adolescents with desmoid tumor treated in 2 French cancer centers with a very long followup were retrospectively reviewed. Results. Median age was 6 years (range, 0-15). Tumors mainly involved the limbs (42%). Five cases occurred in a context of genetic disorder. Surgery was first-line treatment in 80% of cases. Resection was microscopically complete in 3 patients (pts), with a microscopic residue in 19 pts and a macroscopic residue in 35 cases. Various adjuvant therapies were used. Overall response to all systemic therapies was 33%. Thirty-eight patients developed one or more recurrences or progressions. After a median followup of 8.5 years, 34 patients were alive in complete remission (CR), including 16 first CR. Seven patients died, 6 from refractory disease and 1 from colorectal carcinoma in a genetic context. Ten-year progression-free survival (PFS) and overall survival were 31% and 88%, respectively. In univariate analysis, age less than 10 years and head-neck site were favorable prognostic factors for PFS. Conclusions. When surgery is required, surgical margins must be negative. Low-dose chemotherapy can be proposed as adjuvant therapy. Prospective trials must be developed to evaluate long-term response and side effects.

Clinical characteristics and prognosis of osteosarcoma in young children: a retrospective series of 15 cases.

BACKGROUND: Osteosarcoma is the most common primary bone malignancy in childhood and adolescence. However, it is very rare in children under 5 years of age. Although studies in young children are limited in number, they all underline the high rate of amputation in this population, with conflicting results being recently reported regarding their prognosis. METHODS: To enhance knowledge on the clinical characteristics and prognosis of osteosarcoma in young children, we reviewed the medical records and histology of all children diagnosed with osteosarcoma before the age of five years and treated in SFCE (Société Française des Cancers et leucémies de l'Enfant) centers between 1980 and 2007. RESULTS: Fifteen patients from 7 centers were studied. Long bones were involved in 14 cases. Metastases were present at diagnosis in 40% of cases. The histologic type was osteoblastic in 74% of cases. Two patients had a relevant history. One child developed a second malignancy 13 years after osteosarcoma diagnosis.Thirteen children received preoperative chemotherapy including high-dose methotrexate, but only 36% had a good histologic response. Chemotherapy was well tolerated, apart from a case of severe late convulsive encephalopathy in a one-year-old infant. Limb salvage surgery was performed in six cases, with frequent mechanical and infectious complications and variable functional outcomes.Complete remission was obtained in 12 children, six of whom relapsed. With a median follow-up of 5 years, six patients were alive in remission, seven died of their disease (45%), in a broad range of 2 months to 8 years after diagnosis, two were lost to follow-up. CONCLUSIONS: Osteosarcoma seems to be more aggressive in children under five years of age, and surgical management remains a challange.

The "T-construct" for spinopelvic fixation in neuromuscular spinal deformities. Preliminary results of a prospective series of 15 patients.

BACKGROUND: We present the results of a prospective series of 15 patients treated for neuromuscular spinal deformities with an original spinopelvic construct using two sacral screws and two iliac screws. Results were compared to a prospective cohort of 62 patients treated for neuromuscular spinal deformities by spinopelvic fixation using iliosacral screws. METHODS: From November 2005 to June 2007, the clinical data of every patient who underwent spinopelvic fixation for treatment of a neuromuscular spinal deformity were recorded prospectively. RESULTS: Fifteen patients weighting less than 35 kg were operated on with a special segmental construct using two sacral screws and two iliac screws for pelvic anchorage. Sixty-two patients had spinopelvic fixation using iliosacral screws. Severity of the curve (Cobb angle) and reducibility were statistically equal in both groups. Operative time and blood loss were statistically identical in both groups. Curve correction was similar in both groups and postoperative pelvic obliquity ranged between 2° and 4°. No significant loss of correction was noted at the last follow-up. Fifteen patients had early postoperative infection of the posterior wound requiring re-operation. CONCLUSIONS: Despite a high rate of infectious complications, optimal correction of pelvic obliquity requires extension of spinal instrumentation to the pelvis. Pelvic fixation with the "T-construct" did provide effective and improved spinal stabilization in these patients, while reducing the need for a postoperative cast or brace. As a result, patients had a favorable postoperative course with early mobilization and return to a comfortable sitting position.

Intervertebral disc calcification with neurological symptoms in children: report of conservative treatment in two cases.

PURPOSE: Intervertebral calcifications are rare in the paediatric population. Two cases of children with symptomatic intervertebral calcifications responsible for spinal cord compression and neurological compromise are presented. METHODS: The data of two children treated conservatively for a symptomatic intervertebral calcification responsible for spinal cord compression and neurological compromise were retrospectively reviewed. RESULTS: Frontal and lateral radiographs are usually sufficient to determine the presence and extent of the calcified cervical disc protrusion. Conservative treatment with antalgics and bracing was applied in both cases. The two patients were completely free of symptoms 4 weeks after initial treatment. Magnetic resonance imaging screening showed a complete vertebral canal clearance at final follow-up. CONCLUSION: Despite the lack of significance due to the small number of patients, conservative treatment should be considered in children with moderate neurological symptoms due to calcified disc protrusion.

Spinopelvic fixation with iliosacral screws in neuromuscular spinal deformities: results in a prospective cohort of 62 patients.

PURPOSE: The results of a prospective series of 62 patients treated for neuromuscular spinal deformities with spinopelvic fixation using iliosacral screws are presented and discussed. METHODS: Sixty-two consecutive patients diagnosed with neuromuscular disorders were prospectively included. Pelvic obliquity and other angular parameters were measured. RESULTS: Mean age was 15.2 years (11.9 to 19.2 years). Spinal deformity was a thoracolumbar curve in 36 cases, a lumbosacral curve in 14 cases, a lumbar curve in four cases, and a combined thoracic and lumbar curve in eight cases. Lumbo-pelvic correction was done using two different strategies. In 15 patients with a normal frontal spinopelvic balance, the two rods were extended directly down to the iliosacral screws. In 47 patients with pelvic obliquity, iliosacral screws were linked to two short rods. The correction was then corrected by distraction and contraction maneuvers applied between the long and short rods. Postoperative angular parameters showed a good correction of spinal deformity in both groups. Patients with preoperative pelvic obliquity had a satisfactory and stable correction at final follow-up. CONCLUSIONS: The technique of pelvic fixation using iliosacral screws and connectors reduce difficulties and operative time due to the complicated three-dimensional bending of the rods for proper placement within the ilium. In patients with preoperative pelvic imbalance, a powerful pelvic anchorage as the iliosacral fixation allowed to use intraoperative reduction maneuvers. Despite the high rate of infectious complications in our patients, we think that our technique provided effective and improved spinal correction for patients with neuromuscular scoliosis.

New recessive mutations in SYT2 causing severe presynaptic congenital myasthenic syndromes.

OBJECTIVE: To report the identification of 2 new homozygous recessive mutations in the synaptotagmin 2 (SYT2) gene as the genetic cause of severe and early presynaptic forms of congenital myasthenic syndromes (CMSs). METHODS: Next-generation sequencing identified new homozygous intronic and frameshift mutations in the SYT2 gene as a likely cause of presynaptic CMS. We describe the clinical and electromyographic patient phenotypes, perform ex vivo splicing analyses to characterize the effect of the intronic mutation on exon splicing, and analyze the functional impact of this variation at the neuromuscular junction (NMJ). RESULTS: The 2 infants presented a similar clinical phenotype evoking first a congenital myopathy characterized by muscle weakness and hypotonia. Next-generation sequencing allowed to the identification of 1 homozygous intronic mutation c.465+1G>A in patient 1 and another homozygous frameshift mutation c.328_331dup in patient 2, located respectively in the 5' splice donor site of SYT2 intron 4 and in exon 3. Functional studies of the intronic mutation validated the abolition of the splice donor site of exon 4 leading to its skipping. In-frame skipping of exon 4 that encodes part of the C2A calcium-binding domain of SYT2 is associated with a loss-of-function effect resulting in a decrease of neurotransmitter release and severe pre- and postsynaptic NMJ defects. CONCLUSIONS: This study identifies new homozygous recessive SYT2 mutations as the underlying cause of severe and early presynaptic form of CMS expanding the genetic spectrum of recessive SYT2-related CMS associated with defects in neurotransmitter release.

Traumatic transepiphyseal separation of the upper femoral epiphysis following seizures in a 5-month-old child: a case report.

INTRODUCTION: Traumatic transepiphyseal separation of the upper femoral epiphysis is a rare lesion of the hip in children. CASE REPORT: We report a case of conservative treatment of transepiphyseal separation of the upper femoral epiphysis following tonic/clonic seizures in a 5-month-old child. Magnetic resonance imaging confirmed the diagnosis The fracture was maintained with hip spica cast for 6 weeks. At the age of 2, complete healing of the lesion including femoral neck remodeling was noted on frontal and lateral radiographs. There was no radiological evidence of AVN or premature closure of the physis. He continues to be followed up. DISCUSSION: Because of the remodeling potential in young children, we assume not to perform additional reduction procedures in such traumatic lesions.

Case reports: lengthening of a vascularized free fibular graft.

Wide bone resection is sometimes necessary for bone tumors, and reconstruction is a major challenge. Vascularized fibular graft is one alternative but may result in progressive limb-length discrepancy (LLD) in children with substantial growth left. Progressive distraction lengthening with an external fixator is now a standard procedure to generally correct LLD. However, lengthening of free vascularized fibular grafts for lower limb reconstruction has not been reported frequently and then only in small series or case reports. We report our experience with three patients with lengthening after tibial reconstruction with a free vascularized fibular graft and review the literature.

Proximal tibial epiphyseal intraosseous schwannoma: a rare entity.

Schwannoma is a benign nerve sheath tumor most commonly located in the soft tissue. Occasionally, schwannomas involve osseous structures. The rarity of osseous involvement leads to omission of schwannoma from the initial differential diagnosis in the majority of cases. Intraosseous schwannomas arising in children have not been reported. We present the case of a schwannoma affecting the proximal tibial epiphysis in a growing child. Intraosseous schwannomas should be included in the differential diagnosis of lytic epiphyseal benign-appearing bone lesions in children. Its radiographic characteristics mimic those of benign chondroblastoma.

Surgical treatment of severe thoracic scoliosis in skeletally mature patients.

The few number of severe thoracic scoliosis requiring surgical treatment makes the description of its therapeutic course difficult. Twenty-one cases of severe thoracic scoliosis with Cobb's angle >90 degrees were treated surgically in the past 20 years. Surgical treatment was performed because of an evolutive scoliosis or in case of respiratory or functional impairment. All patients underwent posterior approach after a preoperative preparation by the use of halo-traction. In 6 cases, a previous surgical posterior spinal release was performed before the halo-traction period. Fusion achieved in all cases and the final correction was generally better than preoperative reducibility. The surgical course was guided by the poor functional status of these patients, especially concerning respiratory function. Spinal instrumentation was made up of 3 rods with few spinal implants in the majority of the cases. Surgical correction was made by means of rods narrowing without any rod's rotation procedures. Functional improvement, especially respiratory was noted in all the cases. Nevertheless, postoperative spirometries were not significantly different from the preoperative ones. The aesthetic improvement of the rib hump was disappointing making necessary a complementary thoracoplasty in two cases. Surgical treatment of severe thoracic scoliosis remains justified in adults because of a progressive functional and radiological deterioration with respiratory compromise. We performed spinal fusion by posterior approach only, after a preoperative period of halo-traction. The final correction depends on the preoperative reducibility. We noted a functional and respiratory improvement in all the cases.

Expansion of regulatory T cells in patients with Langerhans cell histiocytosis.

BACKGROUND: Langerhans cell histiocytosis (LCH) is a rare clonal granulomatous disease that affects mainly children. LCH can involve various tissues such as bone, skin, lung, bone marrow, lymph nodes, and the central nervous system, and is frequently responsible for functional sequelae. The pathophysiology of LCH is unclear, but the uncontrolled proliferation of Langerhans cells (LCs) is believed to be the primary event in the formation of granulomas. The present study was designed to further investigate the nature of proliferating cells and the immune mechanisms involved in the LCH granulomas. METHODS AND FINDINGS: Biopsies (n = 24) and/or blood samples (n = 25) from 40 patients aged 0.25 to 13 y (mean 7.8 y), were studied to identify cells that proliferate in blood and granulomas. We found that the proliferating index of LCs was low ( approximately 1.9%), and we did not observe expansion of a monocyte or dendritic cell compartment in patients. We found that LCH lesions were a site of active inflammation, tissue remodeling, and neo-angiogenesis, and the majority of proliferating cells were endothelial cells, fibroblasts, and polyclonal T lymphocytes. Within granulomas, interleukin 10 was abundant, LCs expressed the TNF receptor family member RANK, and CD4(+) CD25(high) FoxP3(high) regulatory T cells (T-regs) represented 20% of T cells, and were found in close contact with LCs. FoxP3(+) T-regs were also expanded compared to controls, in the blood of LCH patients with active disease, among whom seven out of seven tested exhibited an impaired skin delayed-type hypersensitivity response. In contrast, the number of blood T-regs were normal after remission of LCH. CONCLUSIONS: These findings indicate that LC accumulation in LCH results from survival rather than uncontrolled proliferation, and is associated with the expansion of T-regs. These data suggest that LCs may be involved in the expansion of T-regs in vivo, resulting in the failure of the host immune system to eliminate LCH cells. Thus T-regs could be a therapeutic target in LCH.

Acute L5 pedicle fracture and contralateral spondylolysis in a 12-year-old boy: a case report.

Acute unilateral L5 pedicle fracture associated with a pre-existing contralateral spondylolysis is a rare lesion. We report a case in a non-competitive 12-year-old boy. We present the clinical, radiological and specific management of this rare condition. The clinical and radiological draft of this patient was reviewed. The follow-up was 30 months after fracture healing. Some cases reported in the literature were analyzed and our clinical findings and therapeutic strategy was compared and discussed. Non-operative treatment was done including full-time bracing in a modified Boston brace incorporating one thigh for 3 months. Plain radiographs and computed tomographic (CT)-scan performed at 3 and 6 months showed progressive healing of the pedicle fracture and no modification of the contralateral isthmic spondylolytic lesion. At final follow-up, the patient was asymptomatic and resumed all his activities. In skeletally immature patients, we think that conservative treatment should be considered as a treatment option for this unusual injury.