O. Hamel

Centre Hospitalier Universitaire Rouen, Rouen, Upper Normandy, France

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Publications (119)86.08 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Anterior screw fixation is a well-recognized technique that is used to stabilize Type IIB fractures of the odontoid process in the elderly. However, advanced age and osteoporosis are 2 risk factors for pseudarthrosis. Kyphoplasty has been described in the treatment of lytic lesions in C-2. The authors decided to combine these 2 techniques in the treatment of unstable fractures of the odontoid. Two approximately 90-year-old patients were treated for this type of fracture. Instability was demonstrated on dynamic radiography in one patient, and the fracture was seen on static radiography in the other. Clinical parameters, pain, range of motion, 36-Item Short Form Health Survey (SF-36) score (for the first patient), and radiological examinations (CT scans and dynamic radiographs) were studied both before and after surgery. After inflating the balloon both above and below the fracture line, the authors applied a high-viscosity polymethylmethacrylate cement. Some minor leakage of cement was noted in both cases but proved to be harmless. The screws were correctly positioned. The clinical result was excellent, both in terms of pain relief and in the fact that there was no reduction in the SF-36 score. The range of motion remained the same. A follow-up CT scan obtained 1 year later in one of the patients showed no evidence of change in the materials used, and the dynamic radiographs showed no instability. This combination of kyphoplasty and anterior screw fixation of the odontoid seems to be an interesting technique in osteoporotic Type IIB fractures of the odontoid process in the elderly, with good results both clinically and radiologically.
    Journal of Neurosurgery Spine 01/2015; · 2.36 Impact Factor
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    ABSTRACT: A large proportion of low back pain may be explained by intervertebral disc (IVD) degeneration. Currently, the process leading to IVD degeneration highlights the pivotal role of IVD cells. The number of these cells drastically decreases and does not support a spontaneous repair of the tissue. In order to counteract IVD degeneration, regenerative medicine, based on a cell supplementation of the damaged tissue is considered as a promising approach. After a description of IVD physiopathology, we will develop the different strategies based on cell therapy and tissue engineering and currently under investigation to improve altered IVD degeneration. Finally, results from the current pre-clinical and clinical studies will be discussed. © 2014 médecine/sciences – Inserm.
    Médecine sciences : M/S. 12/2014; 30(12):1091-100.
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    ABSTRACT: The Brindley procedure, used since the 1980s, consists of implantation of a stimulator for sacral anterior root stimulation combined with a posterior sacral rhizotomy to enable micturition. Patients suitable for the procedure are patients with detrusor overactivity and a complete spinal cord lesion with intact sacral reflexes. S2 to S4 posterior sacral rhizotomy abolishes sacral hyperreflexia and may lead to decreased urethral closure pressure and loss of reflex adaptation of continence, leading to stress incontinence.
    Neurourology and Urodynamics 11/2014; · 2.67 Impact Factor
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    ABSTRACT: Minor head trauma is a common cause for pediatric emergency department visits. In 2009, the Pediatric Emergency Care Applied Research Network (PECARN) published a clinical prediction rule for identifying children at very low risk of clinically important traumatic brain injuries (ciTBI) and for reducing CT use because of malignancy induced by ionizing radiation. The prediction rule for ciTBI was derived and validated on 42,412 children in a prospective cohort study. The Société Française de Médecine d’Urgence (French Emergency Medicine Society) and the Groupe Francophone de Réanimation et Urgences Pédiatriques (French-Language Pediatric Emergency Care Group) recommend this algorithm for the management of children after minor head trauma. Based on clinical variables (history, symptoms, and physical examination findings), the algorithm assists in medical decision-making: CT scan, hospitalization for observation or discharge, according to three levels of ciTBI risk (high, intermediate, or low risk). The prediction rule sensitivity for children younger than 2 years is 100 % [86.3–100] and for those aged 2 years and older it is 96.8 % [89–99.6]. Our aim is to present these new recommendations for the management of children after minor head trauma.
    Archives de Pédiatrie. 11/2014;
  • Morphologie 09/2014; 98(322):97.
  • Intensive care medicine. 08/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Minor head trauma is a common cause for pediatric emergency department visits. In 2009, the Pediatric Emergency Care Applied Research Network (PECARN) published a clinical prediction rule for identifying children at very low risk of clinically important traumatic brain injuries (ciTBI) and for reducing CT use because of malignancy induced by ionizing radiation. The prediction rule for ciTBI was derived and validated on 42,412 children in a prospective cohort study. The Société Française de Médecine d'Urgence (French Emergency Medicine Society) and the Groupe Francophone de Réanimation et Urgences Pédiatriques (French-Language Pediatric Emergency Care Group) recommend this algorithm for the management of children after minor head trauma. Based on clinical variables (history, symptoms, and physical examination findings), the algorithm assists in medical decision-making: CT scan, hospitalization for observation or discharge, according to three levels of ciTBI risk (high, intermediate, or low risk). The prediction rule sensitivity for children younger than 2 years is 100 % [86.3-100] and for those aged 2 years and older it is 96.8 % [89-99.6]. Our aim is to present these new recommendations for the management of children after minor head trauma.
    Archives de pediatrie : organe officiel de la Societe francaise de pediatrie. 06/2014;
  • O. Hamel, B. Perrouin-Verbe
    Annals of Physical and Rehabilitation Medicine 05/2014; 57:e238.
  • O. Hamel, B. Perrouin-Verbe
    Annals of Physical and Rehabilitation Medicine 05/2014; 57:e227.
  • Annals of Physical and Rehabilitation Medicine 05/2014; 57:e242-e243.
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    ABSTRACT: Symptomatic vertebral hemangiomas during pregnancy are rare, as only 27 cases have been reported in the literature since 1948. However, symptomatic vertebral hemangiomas can be responsible for spinal cord compression, in which case they constitute a medical emergency, which raises management difficulties in the context of pregnancy. Pregnancy is a known factor responsible for deterioration of these vascular tumors. In this paper, the authors report 2 clinical cases of symptomatic vertebral hemangiomas during pregnancy, including 1 case of spontaneous fracture that has never been previously reported in the literature. The authors then present a brief review of the literature to discuss emergency management of this condition. The first case was a 28-year-old woman at 35 weeks of gestation, who presented with paraparesis. Spinal cord MRI demonstrated a vertebral hemangioma invading the body and posterior arch of T-3 with posterior epidural extension. Laminectomy and vertebroplasty were performed after cesarean section, allowing neurological recovery. The second case involved a 35-year-old woman who presented with spontaneous fracture of T-7 at 36 weeks of gestation, revealing a vertebral hemangioma with no neurological deficit, but it was responsible for pain and local instability. Treatment consisted of postpartum posterior interbody fusion. With a clinical and radiological follow-up of 2 years, no complications and no modification of the hemangiomas were observed. A review of the literature reveals discordant management of these rare cases, which is why the treatment course must be decided by a multidisciplinary team as a function of fetal gestational age and maternal neurological features.
    Journal of neurosurgery. Spine 03/2014; · 1.61 Impact Factor
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    ABSTRACT: Background. Decompressive craniectomy can be proposed in the management of severe traumatic brain injury. Current studies report mixed results, preventing any clear conclusions on the place of decompressive craniectomy in traumatology. Methods. The objective of this retrospective study was to evaluate the results of all decompressive craniectomies performed between 2005 and 2011 for refractory intracranial hypertension after severe traumatic brain injury. Sixty patients were included. Clinical parameters (Glasgow scale, pupillary examination) and radiological findings (Marshall CT scale) were analysed. Complications, clinical outcome, and early and long-term Glasgow Outcome Scale (GOS) were evaluated after surgery. Finally, the predictive value of preoperative parameters to guide the clinician's decision to perform craniectomy was studied. Results. Craniectomy was unilateral in 58 cases and the mean bone flap area was 100 cm(2). Surgical complications were observed in 6.7% of cases. Mean followup was 30 months and a favourable outcome was obtained in 50% of cases. The initial Glasgow Scale was the only statistically significant predictive factor for long-term outcome. Conclusion. Despite the discordant results in the literature, this study demonstrates that decompressive craniectomy is useful for the management of refractory intracranial hypertension after severe traumatic brain injury.
    The Scientific World Journal 01/2014; 2014:207585. · 1.22 Impact Factor
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    The Scientific World Journal 01/2014; · 1.22 Impact Factor
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    ABSTRACT: Introduction. Spasticity is a disabling symptom resulting from reorganization of spinal reflexes no longer inhibited by supraspinal control. Several studies have demonstrated interest in repetitive transcranial magnetic stimulation in spastic patients. We conducted a prospective, randomized, double-blind crossover study on five spastic hemiparetic patients to determine whether this type of stimulation of the premotor cortex can provide a clinical benefit. Material and Methods. Two stimulation frequencies (1 Hz and 10 Hz) were tested versus placebo. Patients were assessed clinically, by quantitative analysis of walking and measurement of neuromechanical parameters (H and T reflexes, musculoarticular stiffness of the ankle). Results. No change was observed after placebo and 10 Hz protocols. Clinical parameters were not significantly modified after 1 Hz stimulation, apart from a tendency towards improved recruitment of antagonist muscles on the Fügl-Meyer scale. Only cadence and recurvatum were significantly modified on quantitative analysis of walking. Neuromechanical parameters were modified with significant decreases in H max⁡ /M max⁡ and T/M max⁡ ratios and stiffness indices 9 days or 31 days after initiation of TMS. Conclusion. This preliminary study supports the efficacy of low-frequency TMS to reduce reflex excitability and stiffness of ankle plantar flexors, while clinical signs of spasticity were not significantly modified.
    TheScientificWorldJournal. 01/2014; 2014:389350.
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    ABSTRACT: Thirty percent of patients with pudendal neuralgia due to pudendal nerve entrapment obtain little or no relief from nerve decompression surgery. The objective was to describe the efficacy of spinal cord stimulation of the conus medullaris in patients with refractory pudendal neuralgia. This prospective study, conducted by two centers in the same university city, described the results obtained on perineal pain and functional disability in all patients with an implanted conus medullaris stimulation electrode for the treatment of refractory pudendal neuralgia. Twenty-seven consecutive patients were included by a multidisciplinary pelvis and perineal pain clinic between May 2011 and July 2012. Mean follow-up was 15 months. The intervention was an insertion of a stimulation electrode was followed by a test period (lasting an average of 13 days) before deciding on permanent electrode implantation. Maximum and average perineal pain scores and the pain-free sitting time were initially compared during the test and in the long-term (paired t-test). The estimated percent improvement (EPI) was evaluated in the long-term. Twenty of the 27 patients were considered to be responders to spinal cord stimulation and 100% of implanted patients remained long-term responders (mean tripling of sitting time, and mean EPI of 55.5%). Spinal cord stimulation of the conus medullaris is a safe and effective technique for long-term treatment of refractory pudendal neuralgia. Routine use of this technique, which has never been previously reported in the literature in this type of patient, must now be validated by a larger scale study. Neurourol. Urodynam. © 2013 Wiley Periodicals, Inc.
    Neurourology and Urodynamics 11/2013; · 2.67 Impact Factor
  • Annals of Physical and Rehabilitation Medicine 10/2013; 56, Supplement 1:e76.
  • Morphologie 10/2013; 97(s 318–319):72.
  • Morphologie 10/2013; 97(s 318–319):88–89.
  • Annals of Physical and Rehabilitation Medicine 10/2013; 56:e82.
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    ABSTRACT: The intervertebral disc is a complex anatomical structure consisting of a near central gelatinous region, called nucleus pulposus (NP), surrounded by an annular ligament-type structure, the annulus fibrosis, and separated from vertebrae by cartilaginous endplates, which constitute the main nutritive pathway of this core. The cellular and biochemical characteristics of these structures determine the biomechanical properties. Nucleus pulposus distributes pressures applied to the intervertebral disc, thereby tensioning the annulus fibers. The major constraints faced by the intervertebral disc involve multiple phenomena like viscoelastic behavior (playing quickly), but also slower like corporeo-discal exchange related to the porosity of the endplates.
    Revue du Rhumatisme Monographies 09/2013; 80(4):204–209.

Publication Stats

267 Citations
86.08 Total Impact Points

Institutions

  • 2013
    • Centre Hospitalier Universitaire Rouen
      • Service d'Urologie
      Rouen, Upper Normandy, France
  • 2003–2013
    • University of Nantes
      • Faculté de Médecine
      Naoned, Pays de la Loire, France
  • 2012
    • French Institute of Health and Medical Research
      Lutetia Parisorum, Île-de-France, France
  • 2002–2012
    • Centre Hospitalier Universitaire de Nantes
      • • Service de neurotraumatologie
      • • Clinique de chirurgie digestive et endocrinienne
      Naoned, Pays de la Loire, France
  • 2008
    • Hôtel-Dieu de Paris – Hôpitaux universitaires Paris Centre
      Lutetia Parisorum, Île-de-France, France
  • 2005
    • Centre Catherine de Sienne
      Naoned, Pays de la Loire, France
    • Centre Hospitalier de la Côte Basque
      Bayona, Aquitaine, France