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.

[Vitamin D deficiency rickets complicating Dorfman-Chanarin syndrome]

Vitamin D deficiency rickets remains a public health issue in many parts of the world. In France, this diagnosis has almost disappeared since 1992 with routine vitamin D supplementation for children. Therefore, it is more difficult for doctors to identify risk factors and early signs of this disease. In this article, we report a rickets diagnosis acquired by vitamin D deficiency in a child who presented with the onset of a genu valgum and difficulty walking at the age of 9½ years. This patient was a Comorian child followed up from his birth for Dorfman-Chanarin syndrome. Dorfman-Chanarin syndrome is a rare disease, with about 80 cases reported in the literature. It belongs to the group of neutral lipid storage diseases (NLSD) characterized especially on the skin by ichthyosis. This child presented risk factors for vitamin D deficiency (dark skin color, prolonged and exclusive breastfeeding, premature end of supplementation, and particularly severe ichthyosis) that should have alerted us to the risk of vitamin D deficiency and the need for supplementation. This case highlights the importance of vitamin D, especially if there are risk factors such as ichthyosis, and the need to remain watchful in monitoring all chronic diseases.

Proximal ulnar osteotomy in the treatment of neglected childhood Monteggia lesion

INTRODUCTION

The aim of our study was to analyze medium and long-term results of proximal ulnar osteotomy with and without ligament injury in neglected Monteggia injury in children.

MATERIAL AND METHODS

This retrospective, multicenter study included 28 patients. Clinical criteria concerned the range of motion, pain and MEPI score, and radiologic criteria comprised of Storen line, head-neck ratio, radial neck angle, and signs of osteoarthritic remodeling.

RESULTS

Twenty-eight patients were reviewed, at a mean 6 years' follow-up (range, 2-34y). Sixteen had proximal ulnar osteotomy without ligament reconstruction, and 12 had associated ligamentoplasty. Both groups showed significant clinical and radiological improvement, with no significant difference. Patients operated within less than 1 year had better clinical and radiographic results. There was no correlation between age at surgery and quality of results. The 5 patients who underwent condyloradial pinning showed early recurrence of dislocation and osteoarthritic remodeling. The three cases of Bado type-3 lesion had early recurrence of dislocation.

DISCUSSION

Proximal ulnar osteotomy gives good long-term results in Bado type-1 lesions, regardless of age, if performed before 1 year, in the absence of osteoarthritic remodeling. Associated ligamentoplasty does not seem to be useful.

LEVEL OF EVIDENCE

IV (retrospective).

Proximal migration of fibular malleolus during tibial lengthening despite syndesmotic screw fixation: a series of 22 cases

INTRODUCTION

During tibial lengthening procedures, it is recommended to prevent fibular malleolus proximal migration using a distal tibiofibular syndesmotic screw, which is removed at 6 months. We have observed proximal migrations of the fibular malleolus despite placement of this syndesmotic screw.

OBJECTIVE

The objective of this study was to demonstrate this migration and to study the influence of two factors that may favor its occurrence: positioning of the syndesmotic screw and union of the fibula at the time of removal.

HYPOTHESIS

An unhealed fibula at the time the distal tibiofibular syndesmotic screw is removed and its tricortical position promote the proximal migration of the fibular malleolus.

MATERIAL AND METHODS

This was a retrospective, single-center, analytical study that included 22 lengthening procedures in 18 patients from 5 to 17 years of age who had undergone tibial lengthening and presented a preoperative continuous fibula. The position of the fibular malleolus, union of the fibula, and the tri- or quadricortical position of the screw were assessed based on four successive x-rays.

RESULTS

Tricortical positioning of the syndesmotic screw was significantly associated with proximal migration of the fibular malleolus during lengthening (P=0.0248<0.05). However, there was no significant relation between an unhealed fibula and proximal migration of the fibular malleolus when the screw was removed (P=0.164>0.05).

DISCUSSION

Proximal migration of the fibular malleolus during lengthening is promoted by placing a non-quadricortical syndesmotic screw. Quadricortical positioning of the screw should be recommended. Migration of the fibular malleolus after ablation of the syndesmotic screw seems to be related to absence of fibular union but this series was too small to demonstrate this clearly.

LEVEL OF EVIDENCE

Level IV: Retrospective study.

Intraoperative neurophysiologic monitoring in spine surgery. Developments and state of the art in France in 2011

Intraoperative spinal cord monitoring consists in a subcontinuous evaluation of spinal cord sensory-motor functions and allows the reduction the incidence of neurological complications resulting from spinal surgery. A combination of techniques is used: somatosensory evoked potentials (SSEP), motor evoked potentials (MEP), neurogenic motor evoked potentials (NMEP), D waves, and pedicular screw testing. In absence of intraoperative neurophysiological testing, the intraoperative wake-up test is a true form of monitoring even if its latency long and its precision variable. A 2011 survey of 117 French spinal surgeons showed that only 36% had neurophysiological monitoring available (public healthcare facilities, 42%; private facilities, 27%). Monitoring can be performed by a neurophysiologist in the operating room, remotely using a network, or directly by the surgeon. Intraoperative alerts allow real-time diagnosis of impending neurological injury. Use of spinal electrodes, moved along the medullary canal, can determine the lesion level (NMEP, D waves). The response to a monitoring alert should take into account the phase of the surgical intervention and does not systematically lead to interruption of the intervention. Multimodal intraoperative monitoring, in presence of a neurophysiologist, in collaboration with the anesthesiologist, is the most reliable technique available. However, no monitoring technique can predict a delayed-onset paraplegia that appears after the end of surgery. In cases of preexisting neurological deficit, monitoring contributes little. Monitoring of the L1-L4 spinal roots also shows low reliability. Therefore, monitoring has no indication in discal and degenerative surgery of the spinal surgery. However, testing pedicular screws can be useful. All in all, thoracic and thoracolumbar vertebral deviations, with normal preoperative neurological examination are currently the essential indication for spinal cord monitoring. Its absence in this indication is a lost opportunity for the patient. If neurophysiological means are not available, intraoperative wake-up test is a minimal obligation.

Fracture following lower limb lengthening in children: a series of 58 patients

INTRODUCTION

Fracture is one of the main complications following external fixator removal used in cases of progressive lower limb lengthening; rates as high as 50% are found in the literature. The aim of this study was to determine the factors influencing this complication.

MATERIALS AND METHODS

One hundred and eleven cases of lower limb lengthening were performed in 58 patients (40 femurs and 71 tibias). The mean age at surgery was 10.1years old. Lengthening was performed in all cases with an external fixator alone, associated in 39.6% of cases with intramedullary nailing. The patients were divided into three groups according to disease etiology (congenital, achondroplasia and other). The fractures were classified according to the Simpson classification.

RESULTS

Twenty fractures were recorded (18%). Sixteen fractures were found in patients with congenital disease, four with achondroplasia and none in the group of other etiologies. The fracture was more often in the femur (27.5%) than in the tibia (12.7%).

DISCUSSION

The rate of fracture is influenced by different factors depending on the etiology of disease. In congenital diseases, the fracture rate is higher when there is lengthening of more than 15% of the initial length and a delay between surgery and the beginning of lengthening of less than 7days. In patients with achondroplasia, the influence of a relative percentage of lengthening is less important than in those with congenital disease. However, to avoid fractures, lengthening should not be started in children under the age of nine. Moreover, lengthening should begin at least 7days after the fixator has been placed.

TYPE OF STUDY

Retrospective.

LEVEL OF EVIDENCE

Level IV.

Influence of screw type on initial coronal and sagittal radiological correction with hybrid constructs in adolescent idiopathic scoliosis. Correction priorities

BACKGROUND

Pedicle screw constructs for spinal instrumentation in patients with adolescent idiopathic scoliosis (AIS) are effective in providing coronal plane correction but can result in loss of kyphosis, which in turn can lead to loss of lordosis. Hybrid constructs have been found superior over pedicle screw constructs in terms of thoracic kyphosis restoration. In this study, our objective was to compare outcomes with monoaxial versus polyaxial screws in an AIS population treated with hybrid constructs.

HYPOTHESIS

Monoaxial screws provide better correction in the coronal plane but result in loss of thoracic kyphosis, whereas thoracic kyphosis is preserved when polyaxial screws are used.

MATERIAL AND METHODS

We retrospectively analysed data from 60 patients (mean age, 15years) with Lenke 1, 2, or 3 AIS treated using a hybrid construct with self-retaining bilaminar hook claws cranially, pedicle screws between the last instrumented vertebra and T11 caudally, and sublaminar universal clamps between the two extremities of the construct. Monoaxial screws were used in the first 30 patients (MS group) and polyaxial screws in the next 30 patients (PS group). Student's t test was performed to compare the two groups in terms of thoracic Cobb angle correction and T4-T12 kyphosis 3 months after surgery.

RESULTS

No significant preoperative differences were found between the two groups. At last follow-up, the residual Cobb angle was significantly greater in the PS group than in the MS group (20.3° versus 15°) with a percentage of correction of 72.1% in the MS group versus 64.8% in the PS group. In the sagittal plane, the thoracic kyphosis was significantly greater in the PS group than in the MS group (26.6° versus 23°).

DISCUSSION

This preliminary study shows that, even within a population managed using hybrid constructs, which are associated with less iatrogenic hypokyphosis, differences exist according to the technique used. The importance of sagittal spinal balance has been abundantly documented in the literature, and sagittal malalignment, particularly due to iatrogenic factors, is associated with poorer clinical outcomes in adults with spinal deformities. Therefore, there is a critical need to determine whether the treatment priority is optimal correction in the coronal plane or in the sagittal plane. We believe that the main focus should be sagittal plane correction, even at the expense of a slight decrease in coronal plane correction. Long-term studies are needed to confirm our preliminary findings.

Value of diffusion-weighted images in differentiating mid-course responders to chemotherapy for osteosarcoma compared to the histological response: preliminary results

BACKGROUND

Preoperative diffusion-weighted MRI (DW-MRI) has been described as an efficient method to differentiate good and poor responders to chemotherapy in osteosarcoma patients. A DW-MRI performed earlier during treatment could be helpful in monitoring chemotherapy.

OBJECTIVE

To assess the accuracy of DW-MRI in evaluating response to chemotherapy in the treatment of osteosarcoma, more specifically at mid-course of treatment.

MATERIALS AND METHODS

This study was carried out on a prospective series of adolescents treated for long-bone osteosarcoma. MR examinations were performed at diagnosis (MRI-1), at mid-course of chemotherapy (MRI-2), and immediately before surgery (MRI-3). A DW sequence was performed using diffusion gradients of b0 and b900. The apparent diffusion coefficients (ADC1, ADC2, ADC3, respectively), their differentials (ADC2 - ADC1 and ADC3 - ADC1), and their variation (ADC2 - ADC1/ADC1 and ADC3 - ADC1/ADC1) were calculated for each of these three time points.

RESULTS

Fifteen patients were included. Patients with no increase in ADC showed a poor response to chemotherapy on their histology results. At mid-course, the three calculated values were significantly different between good and poor responders. ADC2 - ADC1 enabled us to detect, with 100% specificity, four out of seven of the poor responders. There was no significant difference in the values at MRI-3 between the two groups.

CONCLUSION

DW-MRI performed both at baseline and mid-course of neoadjuvant chemotherapy is an efficient method to predict further histological response of osteosarcoma. This method could be used as an early prognostic factor to monitor preoperative chemotherapy.

Reciprocal sagittal alignment changes after posterior fusion in the setting of adolescent idiopathic scoliosis

PURPOSE

Surgical adolescent idiopathic scoliosis (AIS) management can be associated with loss of thoracic kyphosis and a secondary loss of lumbar lordosis leading to iatrogenic flatback. Such conditions are associated with poorer clinical outcomes during adulthood. The aim of this study was to evaluate sagittal plane reciprocal changes after posterior spinal fusion in the setting of AIS.

METHODS

Thirty consecutive adolescents (mean age 14.6 years) with AIS Lenke 1, 2 or 3 were included in this retrospective study with 2 year follow-up. Full-spine standing coronal and lateral radiographs were obtained preoperatively, at 3 and 24 months postoperatively. Coronal Cobb angle, thoracic kyphosis (TK) and lumbar lordosis (LL) were measured. Surgical procedure was similar in all the cases, with use of pedicular screws between T11 and the lowest instrumented vertebra (≥L2), sublaminar hooks applied in compression at the upper thoracic level and sub-laminar bands and clamps in the concavity of the deformity. Statistical analysis was done using t test and Pearson correlation coefficient.

RESULTS

Between preoperative and last follow-up evaluations a significant reduction of Cobb angle was observed (53.6° vs. 17.2°, p < 0.001). A significant improvement of the instrumented thoracic kyphosis, TK (19.7° vs. 26.2°, p < 0.005) was noted, without difference between 3 and 24 months postoperatively. An improvement in lumbar lordosis, LL (43.9° vs. 47.3°, p = 0.009) was also noted but occurred after the third postoperative month. A significant correlation was found between TK correction and improvement of LL (R = 0.382, p = 0.037), without correlation between these reciprocal changes and the amount of coronal correction.

CONCLUSION

Results from this study reveal that sagittal reciprocal changes occur after posterior fusion when TK is restored. These changes are visible after 3 months postoperatively, corresponding to a progressive adaptation of patient posture to the surgically induced alignment. These changes are not correlated with coronal plane correction of the deformity. In the setting of AIS, TK restoration is a critical goal and permits favorable postural adaptation. Further studies will include pelvic parameters and clinical scores in order to evaluate the impact of the noted reciprocal changes.

Limb lengthening using ankle joint distraction (arthrodiastasis) followed by arthrodesis. Experience with one case

Tibial aplasias are difficult entities to manage and sometimes require significant limb lengthening. Preserving the joint is the preferred option in these cases. However, when function is not ensured, lengthening beginning in the joint can be attempted followed by arthrodesis. This report presents the clinical and radiological results of a patient treated with intra-articular lengthening (or arthrodiastasis) associated with talocrural arthrodesis. Although this original technique provided satisfactory results, this surgical program remains complicated.

Congenital scoliosis: a frontal plane evaluation of 251 operated patients 14 years old or older at follow-up

INTRODUCTION

Congenital scoliosis, carrying an incidence between 0.5 and 1 per 1000 births, raise the problem of their evolutive potential.

HYPOTHESIS

Some predictive factors for the evolution of scoliotic curvature due to congenital vertebral malformation (CVM) can be found.

MATERIAL AND METHODS

This was a retrospective multicenter study of 251 patients, at least 14 years old when evaluated at end of follow-up, with CVM and spinal deformity predominating in the frontal plane.

RESULTS

38.8% of patients showed associated neurologic, visceral or orthopedic abnormalities. CVM was single in 60.6%, double in 20.3%, triple in 6.4% and multiple in 12.7% of cases. 34.1% of CVMs were thoracic. Congenital scoliosis curvature was single in 88.8% of patients, double in 10% and triple in 1.2%. Mean curvature angle was 31.7° at diagnosis (range, 0-105°) and 41.3° preoperatively (range, 10-105°). Sixty-one patients showed associated kyphosis. Mean change in postoperative curvature angle over follow-up was 1.6° (range, -20° to 38°) in the 73 patients managed by arthrodesis, -0.4° (-24° to 30°) in the 64 managed by epiphysiodesis, and 0.4° (-18° to 35°) in the 49 managed by hemivertebral (HV) resection. Results were found to correlate significantly with age at surgery for patients managed by epiphysiodesis, but not for those managed by HV resection or arthrodesis.

DISCUSSION

More than 30% of congenital scolioses involve associated intraspinal abnormality. All CVM patients should therefore undergo medullary and spinal MRI to assess the CVM in all three planes, and the medullary canal and its content. The evolution of scoliotic curvature induced by CVM is hard to predict. Several factors are to be taken into account: CVM type, number and location, and patient age. Curvature progression may be slow or very fast. It accelerates during the peak of puberty, stabilizing with bone maturity. Surgery is mandatory in evolutive scoliosis. Four procedures may be recommended, according to type of CVM and especially to patient age: arthrodesis, convex epiphysiodesis, HV resection or rib distraction. Surgery seeks to correct the spinal deformity induced by the CVM and prevent compensatory curvature and neurologic complications, while conserving sagittal and frontal spinal balance and sparing as many levels as possible. In case of HV involvement, the procedure of choice is CVM resection, which provides 87.5% good results in this indication; the procedure is relatively safe, conservative of spinal levels, and without age limit.

LEVEL OF EVIDENCE

Level IV. Retrospective study.

Fatal lung metastasis secondary to index finger giant cell tumor in an 8-year-old child

We report the case of a 7-year-old girl presenting with giant cell tumor (GCT) of the index finger, complicated by lung metastases. Index disarticulation, pulmonary metastasectomy and chemotherapy failed to produce a cure, and the child died at the age of 8 years after 1 year's evolution. The pulmonary metastases were discovered following hypoxia during initial biopsy. A review of the literature shows this observation to be original, in terms of the patient's age and of the location, onset and fatal outcome of metastasis. The hypoxic episode complicating biopsy raises the issue of early screening for lung metastases in GCT. Pulmonary dissemination of GCT is of severe prognosis.

Surgical treatment of the symptomatic os trigonum in children

Symptomatic os trigonum is a rare condition, well described in adults, that causes chronic ankle pain. To date there are no reported cases of successfully managed symptomatic os trigonum in the children population. We retrospectively reviewed four paediatric patients (11-17 years of age) successfully operated for a symptomatic os trigonum using an open excision through a posteromedial approach. One case was bilateral. Postoperative pain relief was obtained in all cases. All of the patients were able to return to unrestricted physical activities after three months. The average follow-up was 12 months. Symptomatic os trigonum may be held responsible for chronic ankle pain in children and adolescents as well as in adults. The surgical treatment is effective in children.

[Progressive correction of the hand in the congenital radial clubhand]

The therapeutic objective of a congenital radial clubhand is to obtain, at the end of the growth, a functional hand, that is a hand with a thumb, in the axis of the forearm with the most cosmetic aspect as possible. The challenge lies in the fact that the hand is not in the axis of the forearm. Thus, some authors realize a surgical centralization or radialization by doing a direct release of the retracted soft tissues. On the other hand, it is possible to correct the hand without any invasive surgery by using an external fixator allowing to correct the hand progressively. The Taylor Spatial Frame fixator is a system of external fixation which allows, by using a software, to realize this correction accurately.

[Ankle injury without fracture in children: cast immobilization versus symptomatic treatment. Impact on absenteeism and quality of life]

Treatment methods for ankle injury in children are numerous and have comparable results. The impact on absenteeism and quality of life is an interesting criterion to consider in order to help doctors in their initial treatment choice.

OBJECTIVE

The objective of this study was to compare two therapeutic strategies for ankle injury without fracture in children in terms of the impact on school absenteeism, parents' professional absenteeism, and quality of life. The strategies compared were cast immobilization of the ankle and a purely symptomatic treatment with no immobilization.

MATERIALS AND METHOD

We conducted a prospective, comparative, and randomized study. The population comprised children between 8 and 15 years of age, consulting for a first episode of ankle injury in a pediatric-emergency department of a hospital center in Marseille, France. A clinical and radiographical report was systematically done. Children were seen after 1 week to provide the clinical monitoring, assess the child's and parents' absenteeism, and assess the quality of life.

RESULTS

Sixty-two patients were studied. There was no difference in clinical progression after 7 days between the two treatment groups. Quality of life was also comparable. However, the children's absenteeism and the parents' absenteeism were higher in the casted group.

[Melorheostosis and anterior cruciate ligament tear in a 15-year-old female]

We report the case of a 15-year-old girl who suffered an indirect knee trauma. The standard X-rays revealed a tract of ivory-like bone partially obstructing the medullary canal of the femur and the tibia. Magnetic resonance imaging produced a hypointense signal on the T1 and T2 sequences. The radiographic diagnosis was melorheostosis which was confirmed on the biopsy specimen which ruled out other diagnoses. The MRI also revealed a tear of the anterior cruciate ligament, treated conservatively. Clinical and radiological surveillance were proposed for the melorheostosis.

[Informative value of the popliteal angle in walking cerebral palsy children]

PURPOSE OF THE STUDY

In clinical practice, it is generally accepted that hamstring tightness results in incomplete knee extension when the hip is in flexion and in smaller conventional and modified popliteal angles. Similarly, a difference between the conventional popliteal angle and the modified popliteal angle (popliteal differential) would be associated with a permanent deficit in knee extension. The purpose of this study was to determine whether these two hypothesis correlate with clinical findings.

MATERIAL AND METHODS

The series was composed of 35 walking cerebral palsy children, 16 girls and 19 boys, mean age 11+/-3.6 years with a pathological conventional popliteal angle. These children walked using the jump knee (n=24) or the crouch knee (n=11) pattern. Permanent hip flexion and the conventional and modified popliteal angles were noted. SPSS version 10.1.3 for Window was used to search for a correlation between the popliteal differential and the presence of permanent hip flexion using several values for the popliteal differential (5, 10, 15, 20, and 30 degrees ). Data were adjusted for age and gender.

RESULTS

The statistical analyses demonstrated a significant relationship between the presence of permanent hip flexion and a popliteal differential strictly less than 10 degrees and between the absence of permanent hip flexion and a popliteal angle greater or equal to 10 degrees . These statistically significant results, which demonstrated the opposite of what was expected, were independent of age and gender.

DISCUSSION

Our findings demonstrate that examination of the knee joint is indispensable but insufficient. The conventional popliteal angle is not a reliable indicator of hamstring tightness. The normal value of the modified popliteal angle has not been established so that it is impossible to determine what a pathological angle is. We do not know whether measurement of this angle is sufficient to establish indications for surgery. In the future, the development of muscle models coupled with gait analysis should enable more reliable prediction of outcome after surgery. At the present time, we recommend repeated physical examination using a standardized protocol, taking into consideration, several parameters including spasticity, selectivity and muscle force and to perform quantified gait analysis before scheduling hamstring lengthening surgery for walking cerebral palsy children.

[Complications of prophylactic pinning for unilateral upper femur epiphysis slipping: retrospective analysis of 62 operated cases]

PURPOSE OF THE STUDY

The appropriate treatment for unilateral slipping of the upper epiphysis of the femur is controversial. Prophylactic surgical treatment raises the risk of bilateralization. The procedure is often unnecessary as the natural history of epiphyseal slipping is often favorable when the displacement is minimal. We analyzed the complications of systematic prophylactic treatment in order to determine the optimal attitude.

MATERIAL AND METHODS

This was a retrospective series of 62 children who underwent surgery for unilateral slipping of the superior femoral epiphysis between 1996 and 2005. Prophylactic treatment of the healthy hip was instituted systematically. The complications were noted according to Paley. We searched for factors of risk of complications, studying the bone maturity indexes, the characteristic features of the healthy femur epiphysis and the surgical technique used.

RESULTS

There were seven complications, six following prophylactic treatment and one after material removal. The rate of complications reached 11.3%. Five of the complications were minor: two local infections with favorable outcome and three patients who complained of pain in the hip at mobilization, which had totally resolved at one year. One moderate complication was noted: spiral fracture of the upper femur starting from the screw head and treated with plate fixation. The outcome was favorable. There was one severe complication: osteoarthritis of the hip joint with septicemia on day 3. The outcome was unfavorable with necrosis of the femoral head, resection and use of a spacer. A total hip arthroplasty was performed at one year.

DISCUSSION

Complications were globally more frequent and more severe compared to series using prophylactic screwing. The major infection complication (osteoarthritis) observed in this series has not been reported elsewhere. There was probably a center effect since we recruited all of the most complex cases in our region. We were unable to identify any factor predictive of complications. There is apparently no clear choice between systematic prophylactic treatment and careful surveillance. Prophylactic treatment in selected patients might be the key to a successful preventive approach.

[Osteoid osteoma of the inferior articular process of L5 associated with a bilateral spondylosis: a case report]

We report the case of an 8-year-old boy who presented an osteoid osteoma of L5 associated with bilateral spondylolysis involving the same vertebra. Diagnostic bone scintigraphy is highly contributive in children presenting back pain. For us, it is the first intention exploration in patients with isthmic lysis seen on the plain x-ray. Symptomatic spondylolysis is the most frequent cause of back pain in children and is much more frequent than vertebral osteoid osteoma. The presence of isthmic lysis associated with focal uptake on the bone scintigraphy is highly suggestive of symptomatic spondylolysis. In this context, magnetic resonance imaging should be performed for both diagnostic purposes and prognostic assessment. The degree of bone and soft tissue edema in the present case was unusual for symptomatic spondylolysis. Complementary computed tomography finally established the diagnosis of osteoid osteoma of the posterior vertebral arch. To our knowledge, the association of osteoid osteoma with bilateral spondylolysis on the same vertebra has not been described elsewhere. In children, the diagnosis of symptomatic spondylolysis can only be established after ruling out other causes of back pain. The diagnosis of osteoid osteoma must be kept in mind.

Immunohistochemical expression of ezrin correlates with Event-free and overall survival in osteosarcomas

10035

Background: Ezrin is a cytoskeleton linker protein that is actively involved in the metastatic process of cancer cells. We have searched for a pronostic value of ezrin and some of its partners: a-smooth actin and CD44H in 37 patients with an osteosarcoma. Methods: Automate immunohistochemistry (IHC) with anti-ezrin, a-smooth actin and CD44H antibodies was performed in 37 biopsies before chemotherapy, 16 resected tumors of “poor” responders and 13 metastases. In addition the mRNA levels of ezrin of 13 frozen biopies and 4 metastases were evaluated by real time quantitative RT PCR. All results were correlated to the following clinical data: response to chemotherapy, onset of metastasis, event-free survival (EFS) and overall survival (OS). Results: Ezrin expression by IHC was found in 62% of 37 biopsies in the different histological subtypes especially chondroblastic osteosarcomas while chondrosarcomas were negative. A good correlation was found between positive or negative samples by IHC and mRNA levels. Ezrin expression was recorded in 84.5% of metastastic samples. The mean expression of ezrin was higher in metastases than biopsies (mean expression 38.1% versus 17.32%; p=0.024) but the onset of metastasis was not statistically correlated to ezrin positivity on biopsy (p = 0.183). In multivariate analysis, ezrin was an independent prognostic marker for EFS and OS with p<0.001 and p=0.003 respectively and a-smooth actin for OS only (p=0.024). No prognostic value was found for CD44H. Conclusions: We have shown that ezrin is expressed in the different subtypes of osteosarcomas especially chondroblastic osteosarcomas. Other studies are required to confirm that ezrin could be a useful tool for differential diagnosis with chondrosarcoma. Ezrin was an independent prognostic factor for event-free and overall survival rate in multivariate analysis and its partner a-smooth-actin was also an independent prognostic factor for overall survival only. These data confirm the role of ezrin signalling pathway for tumor dissemination in osteosarcomas in vivo. This also might be of interest for therapeutic strategy to select patient for dose intensification or to use new anticancer agents such as rapamycin which reduces experimental lung metastases through an ezrin-related pathway.

No significant financial relationships to disclose.

Rupture de l’artère brachiale et paralysie radiale secondaire à une exostose proximale de l’humérus chez une enfant de 14 ans

Rupture of the brachial artery associated with radial nerve palsy in a context of exostosis of the proximal humerus has not been described to date in the literature. Our patient was a fourteen-year-old girl with a history of violent pain occurring suddenly with no prodrome or triggering factor. The pain was localized at the level of the proximal left humerus. Physical examination revealed the presence of a hematoma and complete motor radial nerve palsy. The diagnosis was not confirmed by computed tomography with contrast injection but was confirmed by magnetic resonance imaging which eliminated malignant transformation of the exostosis. After checking the neurovascular bundles and evacuating the hematoma, treatment consisted in resection of the exostosis and arterial repair with an autologous venous graft. We discuss the diagnostic and therapeutic challenges which present vascular complications due to exostosis.

[Fracture of the intercondylar eminence of the tibia type II in children: 20 surgically-treated cases]

PURPOSE OF THE STUDY

The purpose of this study was to detail therapeutic indications for fractures of the intercondylar eminence of the tibia with little displacement and preservation of the posterior hinge (type II fracture in the Zarincznyj classification).

MATERIAL AND METHODS

We reviewed retrospectively a multicentric serie of type II fractures of the intercondylar eminence observed in children treated surgically. There were twenty patients, ten girls and ten boys, mean age 11.9 years (range 6-16). Imaging included plain x-rays of the knee (anteroposterior and lateral views) in all patients as well as computed tomography (5 patients) and magnetic resonance imaging (1 patient). Surgical treatment was performed in all cases, on average six days after trauma (range 0-25). A medial parapatellar arthrotomy was used in all cases. A non-resorbable thread was used for fixation associated with an anchor in the last four cases. Clinical and radiological assessment was reviewed at mean 3.7 years follow-up.

RESULTS

All children had resumed their sports activities at the same level as before the accident within 4.8 months on average. None of the children suffered from an unstable knee or functional impairment at last follow-up. The Lysholm score was 88.9 on average (range 70-100) at three months postoperative and 99.2 (range 89-100) at last follow-up.

DISCUSSION

There is currently agreement that non-displaced fractures of the anterior intercondylar eminence of the tibia should be treated orthopedically and that forms with displacement require surgery. Conversely, the type II fractures with an anterior gap but a preserved posterior hinge, the appropriate treatment remains a subject of debate. In our experience, surgery would appear to be preferable to orthopedic management. Surgery enables putting correct tension on the anterior crucicate ligament and limits the risk of residual laxity which, even though rarely associated with instability, could in the long-term lead to osteoathritic degradation or meniscal damage.

CONCLUSION

Surgical treatment of fractures of the intercondylar eminence of the tibia with little displacement and preservation of the posterior hinge provides satisfactory results and the best guarantee of long-term stability.

Radiographie des scolioses : dosimétrie comparée entre la technique conventionnelle et la fluorographie numérique

OBJECTIVE

Compare the irradiation delivered in conventional radiography and digital radiography by image intensifier during a scoliosis workup.

PATIENTS AND METHODS

Our prospective randomized study included 105 patients, all of whom were identified according to sociodemographic parameters as well as criteria evaluating the quality of the full front spinal x-ray at PA incidence. The entry dose at the scapula and the exit dose in interorbital, thyroid, mammary, and hypogastric projection was measured by thermoluminescent dosimeters.

RESULTS

The results of 71 girls and 28 boys, aged a mean 13.8 years with a mean weight of 47 kg were analyzed. At equal image quality, the entry dose was not significantly different between the two techniques; the mean exit dose reduction was 64% during digital acquisition. This reduction involved the interorbital (162%), mammary (43%), and thyroid (309%) regions. However, this system is more irradiating in the hypogastric region (34%).

CONCLUSION

The dosimetric evaluation of the different imaging techniques used to explore the entirety of the spine should be part of radiologists' quality standard used to document their work and their choices.

Dermo-hypodermite nécrosante compliquant la varicelle chez l’enfant sous anti-inflammatoires non stéroïdiens

We report two cases of fasciitis with necrotizing hypodermitis of the foot and arm which complicated varicella in immunocompetent children given nonsteroidal anti-inflammatory drugs. The skin barrier and immune function are weakened by the varicella zoster virus. Exposure to nonsteroidal anti-inflammatory drugs further favors necrotizing cutaneous infections caused by group A beta hemolytic streptococci. MRI can confirm the presence of superficial aponevrosis necrosis defining necrotizing fasciitis but should not retard surgical management which is always indicated for necrotizing fasciitis and sometimes for necrotizing dermo-hypodermitis.

Relationship between formation of the femoral bicondylar angle and trochlear shape: Independence of diaphyseal and epiphyseal growth

During hominin evolution, an increase in the femoral bicondylar angle was the initial change that led to selection for protuberance of the lateral trochlear lip and the elliptical profile of the lateral condyle. No correlation is found during ontogeny between the degree of femoral obliquity and of the prominence of the lateral trochlear lip. Might there be a relationship with the elliptical profile of the lateral condyle? On intact femoral diaphyses of juvenile humans and great apes, we compared the anteroposterior length of the lateral and medial sides of the distal metaphysis. The two diaphyseal pillars remain equal during postnatal growth in great apes, while the growth of the lateral pillar far exceeds that of the medial pillar in humans. Increase in bicondylar angle is correlated with disproportionate anteroposterior lengthening of the lateral pillar. The increased anteroposterior length of the lateral side of the metaphysis would contribute to increasing the radius of the curvature of the lateral condyle, but not to the projection of the lateral trochlear lip. The similar neonatal and adult femoro-patellar joint shape in humans prompted an assessment of the similarity during growth of the entire neonatal and adult epiphyses. We showed that the entire epiphysis undergoes drastic changes in proportions during postnatal growth. Finally, we emphasize the need to distinguish the cartilaginous phenotype and the ossified phenotype of the distal femoral epiphysis (and of any epiphysis) during postnatal growth. This crucial distinction applies to most postcranial bones, for they almost all develop following the process of endochondral ossification.

[Shoulder arthrodesis with vascularized fibular graft after tumor resection of the proximal humerus]

PURPOSE OF THE STUDY

Resection of malignant tumors of the proximal humerus often requires dissection of the rotator cuffs and the deltoid muscle. There is no consensus on the ideal method for shoulder reconstruction. We report the functional outcome in a homogeneous series of eight patients treated by arthrodesis using a vascularized free fibular flap.

MATERIAL AND METHODS

Eight patients were included in this study. All had an aggressive tumor of the upper humerus. Tumor resection was associated with a rotator cuff and deltoid muscle resection in all patients. All patients then underwent shoulder arthrodesis using a free vascularized fibular flap fixed with a plate. Clinical and radiological evaluation was available for six patients at mean 28 months. The Musculoskeletal Tumor Society function score was used to assess overall function of the upper limb. The cosmetic outcome and radiographic bone healing as well as hypertrophy of the fibular graft were noted.

RESULTS

Active abduction and active flexion were 82 degrees on average. All patients could bring their hand to the mouth. Circumduction was possible but limited in amplitude. The mean function score was 26.5/30 with an excellent functional outcome in all patients. The cosmetic outcome was considered poor by all patients. Radiographically, bone healing was achieved at last follow-up in all patients but there was one case of failed fusion between the fibular graft and the scapula which required secondary iliac grafting. Mean fibular graft hypertrophy was 32.8% at last follow-up.

DISCUSSION AND CONCLUSION

Two reconstruction methods have been described for patients who require tumor resection of the upper humerus: reconstruction with preservation of glenohumeral joint function and shoulder arthrodesis. Many techniques have been described for each method. It is however difficult to compare the different series reported in the literature because rotator cuff and deltoid muscle resection was not systematically performed and reconstruction methods varied between patients. An analysis of the literature shows that preservation of motion of the scapular glenoid joint can give good functional results when the rotator cuff and deltoid muscle can be preserved. If they cannot, results favor shoulder arthrodesis which provides the patient with very satisfactory upper limb function. Use of a vascularized fibular flap has provided very good arthrodesis results. The patient must however be informed of the probable poor final cosmetic result.

Résultats à maturité osseuse après résection d’hémivertèbres par double abord

PURPOSE OF THE STUDY

The natural history of congenital scoliosis or kypho-scoliosis resulting from a hemivertebra is well documented. The spinal deformation generally worsens in children with a free or semi-segmented hemivertebra situated in the thoraco-lumbar, lumbar or lumbosacral region.

MATERIAL AND METHODS

From 1982 to 1997, fifteen pediatric patients with 15 hemivertebrae causing progressive scoliosis or kypho-scolisosis underwent hemivertebral resection via a double posterior and anterior approach associated with convex fusion. Mean age at surgery was 4.4 years. The fifteen patients were reviewed at bone maturity (Risser 4 or 5) to assess outcome.

RESULTS

Genitourinary tract anomalies were associated in five of the 15 patients and intrathecal anomalies in two. Mean follow-up was 12.1 years. Segmental scoliosis was 30.2 degrees preoperatively, 12.3 degrees postoperatively and 8.9 degrees at last follow-up. The values for total scoliosis were 30.5 degrees, 12.3 degrees and 12.6 degrees respectively. This was a 70.5% improvement at last follow-up for segmental scoliosis and 58.7% for total scoliosis. The real trunk imbalance improved from 31% preoperatively to 9% at last follow-up. All these differences were significant.

DISCUSSION

The main objective of surgical treatment for congenital scoliosis due to hemivertebra is to prevent the development of severe deformation which would necessitate a dangerous and difficult procedure to achieve correction. Resection of the hemivertebra via a double approach is the ideal method for early correction. The procedure not only corrects the spinal deformation but also prevents later deterioration. Correction should be performed as early as possible. The result is sustained over time if there is no other associated spinal anomaly. The procedure is safe and the technique well controlled in experimented hands. Patients need to wear a corset for only six months after resection of the hemivertebra.

[Radiological index as a predictive factor of kyphosis in spina bifida]

PURPOSE OF THE STUDY

The aim of this work was to validate the pertinence of a radiological index (P/A) used as a predictive factor for risk of kyphosis in children with spina bifida. P/A is defined as the ratio between P, the distance between the posterior vertebral wall and the remnant of the posterior arch, over A, the distance between the anterior wall and the posterior vertebral wall, measured on the lateral view of the spine in the most dysplastic vertebra before one year of age.

MATERIAL AND METHODS

The files of 163 children were reviewed. The value of the P/A ratio was measured on lateral views of the spine obtained before the age of one year. The bone level on the anteroposterior film was also noted. The presence or absence of kyphosis was determined from the lateral views obtained at ten years of age. Paired variable analysis was used to compare the mean differences in P/A at one year and at ten years in 31 patients with a bone level of L1 or higher. The exact Fisher test was used to determine the difference in the kyphosis distributions in patients with a bone level of L1 or higher between those with P/A < or = 1/2 and the others. In addition, the specificity, sensitivity, and positive predictive value of a positive test (bone level L1 or higher and P/A < or = 1/2) for development of kyphosis were calculated. Results There was no statistically significant difference in the P/A mean value before the age of one year and after ten years. The distribution of patients with kyphosis was different between patients with a bone level of L1 or higher and P/A < /2 and the other patients (p < 0.01). Considering having a bone level of L1 or higher and a P/A < or = 1/2 as a prognostic test, the specificity was 100%, the sensitivity 87.56%, and the positive predictive value 100%. Many patients with spina bifida will develop kyphosis in the course of life. This spinal deformation raises many specific problems for patient management. Use of a radiological index as presented here allows early detection of patients at risk and can also predict which patients will remain free of deformation. This allows a selection of patients who can benefit most from more regular surveillance of the spinal static and avoid unnecessary radiographic examinations in others.

Unusual phenotype with progressive vertebral fusion in a girl with an apparently balanced t(10;20)(p11;p13) translocation

We report the case of a girl presenting with an unusual form of multiple joint fusion. Skeletal abnormalities consisted of radioulnar synostosis and vertebral fusions without any carpal, digital or tarsal involvement, and broad ribs and clavicles. Spinal X-rays were available from age 4 to 21, demonstrating that the spinal involvement was progressive and led to a complete anterior and lateral fusion of vertebrae. A complete sequencing of the NOGGIN gene failed to find any mutation. In addition, this girl was carrier of an apparently balanced reciprocal translocation t(10;20)(p11;p13). We investigated the role of the BMP2A gene as a potential candidate gene. Fluorescence in situ hybridization with YAC probes from chromosome 20 showed that the BMP2A gene was not disrupted by the translocation breakpoint.

[Multifocal osteomyelitis as the first manifestation of chronic granulomatous disease]

Chronic granulomatous disease is a rare immune disease related to an anomaly in phagocytes NADPH oxidase. The characteristic clinical feature is early recurrent and sometimes serious infection. We report the case of a 22-month-old child who developed multifocal osteomyelitis, an unusual inaugural manifestation of chronic granulomatous disease. Septic chronic granulomatous disease is an uncommon differential diagnosis in children who develop recurrent infections. Diagnosis is established with specific blood tests: reduction of tetrazolium nitroblue, chemoluminescence test, molecular analysis. Therapeutic management must be undertaken as early as possible in order to preserve the long-term prognosis. No curative treatment is currently available. Aggressive treatment of each infectious focus with an adapted antibiotic regimen and in certain cases surgical debridement is required in addition to long-term antibiotic prophylaxis.

[Anatomic study of the anterior patellar groove in the fetal period]

PURPOSE OF THE STUDY

We performed a biometric analysis of the femoral trochlea in the fetus and compared our findings with those observed in adults in order to search for correlations with other biometric parameters of the femur.

MATERIAL AND METHOD

Twenty-two fetuses (44 knees) conserved in formol and free of known orthopedic disease were studied. Fetal age ranged from 26 to 40 weeks. After anatomic dissection, digitalized images were used to obtain angle measurements with a dedicated software. Measurements made on the distal epiphyseal view were: anteroposterior dimension of the condyles, medial and lateral protrusion of the trochlear borders, difference in condyle height, length of the trochleal borders, alpha angle of the trochlear groove, trochlear slope. Measurements made on the AP femoral view were: femoral anteversion, length of the femoral neck, neck-shaft angle. Spearman's test was used to search for correlations. Results were compared with measurements obtained under the same conditions in a series of 32 adult knees published by Wanner.

RESULTS

The trochlear alpha angle was 148 degrees (coefficient of variation 4%). The angle was greater than 150 degrees for 18 trochleae. The lateral border of the trochela was higher than the medial border in 37 of the 44 knees. There was no correlation with age and gender. Femoral anteversion was 27.01 degrees, with a high coefficient of variation (46%), and no correlation with the trochlear alpha angle. Comparison with measurements made on the adult knees revealed no significant difference.

DISCUSSION

This is the first report of statistically significant biometric data of the fetal trochlea. The morphology of the lower femur observed during the third trimester of fetal live is the same as observed in adults. Morphological changes in the proximal femur occurring during growth do not appear to modify the morphology of the distal femur. The asymmetrical ingression of the patella into the trochlea, characteristic of modern man, is considered to result from bipedalism. Our study would suggest that the anatomic characteristics of the trochlea could have been integrated into the genoma during the course of evolution. This would be in favor of a genetic origin of trochlear dysplasia.