Revue de Chirurgie Orthopédique et Traumatologique, 2018
Plusieurs types d'instabilité atlanto-axoïdienne peuvent justifier une fixation chirurgicale. L'a... more Plusieurs types d'instabilité atlanto-axoïdienne peuvent justifier une fixation chirurgicale. L'arthrodèse instrumentée par vissage des masses latérales de C1 et des isthmes de C2 décrite par Harms est une technique exigeante mais qui permet une stabilisation pérenne. Elle est associée à des complications nerveuses ou vasculaires liées à la configuration des rapports anatomiques locaux. Les technologies de navigation per-opératoire permettent d'améliorer la précision technique. Cette série présente 11 cas d'arthrodèse C1C2 type Harms réalisées sous navigation et contrôle peropératoire 3D. Toutes les procédures ont pu être menées à leur terme avec une disposition adéquate des implants. Aucun événement indésirable propre à l'arthrodèse n'est survenu dans la période peri-opératoire. Aucune effraction corticale n'a été constatée sur le contrôle tomodensitométrique cone bean (Oarm ®) réalisé en fin d'intervention. Les difficultés techniques et les risques des arthrodèses C1C2 type Harms conduisent à utiliser les contrôles d'imagerie 3D peropératoires lorsqu'ils sont disponibles.
Revue de Chirurgie Orthopédique et Traumatologique, 2016
Note de technique Apport de l'imagerie 3D naviguée en chirurgie de résection tumorale osseuse pel... more Note de technique Apport de l'imagerie 3D naviguée en chirurgie de résection tumorale osseuse pelvienne ଝ
Open Access Rheumatology: Research and Reviews, 2019
Background and objective: There is absence of data on the prevalence of osteoporosis before corre... more Background and objective: There is absence of data on the prevalence of osteoporosis before corrective surgery of the lumbar spine. We do not know the impact of bone assessment before corrective spine surgery, regarding the prevalence of osteoporosis, risk factors for osteoporosis, and prescription of osteoporotic treatment. Our objective was to evaluate the impact of assessment of bone status before corrective surgery of the lumbar spine. Methods: This retrospective study was conducted over a period of 30 months. Patients included were over 50 years old and had been referred to rheumatology consultation prior to corrective surgery of the lumbar spine with osteosynthesis, for scoliosis or spondylolisthesis. Assessment of bone status consisted in looking for risk factors for osteoporotic fracture, performing bone densitometry with the calculation of TBS (trabecular bone score) and the possible introduction of treatment for osteoporosis. Data were collected on complications related to bone fragility during follow-up. Results: Twenty-eight patients with a median age of 71.2 years (55.5-84.8) were included; 89% were women. T score was <−2.5 in 14.3% (4/28) and −1 to −2.5 in 42.9% (12/28) on at least one of the three sites analyzed. Fifty percent of patients had a TBS <1.2, a history of more than four falls per year, a duration of more than 20 s in the Timed Up and Go Test, and/ or sedation treatment. Vitamin-calcium supplementation and treatment for osteoporosis were prescribed in 71.4% and 17.8% of cases, respectively. During follow-up, 3 patients had one or more osteoporotic vertebral fractures and 4 patients had loosening of implanted devices. Conclusion: Despite a low prevalence of densitometric osteoporosis and therapeutic management, one in four patients had a bone complication, suggesting the superiority of TBS as an indicator of bone status.
Orthopaedics & traumatology, surgery & research : OTSR, 2018
Several types of atlantoaxial instability can justify surgical fixation. The instrumented fusion ... more Several types of atlantoaxial instability can justify surgical fixation. The instrumented fusion procedure described by Harms with screw fixation of the C1 lateral masses and C2 pedicles is a demanding technique that provides lasting stabilization. However, it has been associated with nerve and vascular complications due to the local anatomical configuration. Surgical navigation systems can help improve the procedure's accuracy. We describe a series of 11 cases of C1C2 Harms fusion performed with surgical navigation and intraoperative 3D imaging checks. All procedures were carried out completely with satisfactory implant placement. There were no adverse events related to the procedure during the peri-operative period. No cortical breach was detected using cone-beam CT at the end of the procedure. The technical challenges and risks associated with C1C2 Harms fusion have led to the use of 3D intraoperative imaging systems, when available.
Spinal meningiomas are slow-growing intradural-extramedullary tumors. They are usually associated... more Spinal meningiomas are slow-growing intradural-extramedullary tumors. They are usually associated with good outcomes. However, there are few descriptions of factors predictive of impaired evolution. Our objective was to identify predictive factors of post-operative deterioration as well as outcomes at follow-up. Between 2009 and 2016, 87 patients had surgery for spinal meningioma in our referral center. Clinical presentation, management and outcomes were reported during the post-operative period and at 3-month follow-up. Evaluation was based on post-operative neurological deterioration defined as an increase of at least one point in the McCormick score compared to the status at admission. During the study period, post-operative deterioration occurred in 17 patients (19.5%). Risk factors associated with this deterioration were the absence of pre-operative neurological signs (Relative Risk; RR = 2.38, p = 0.04), an anterior location of the meningioma and a grade 2 meningioma on WHO cl...
Revue de Chirurgie Orthopédique et Traumatologique, 2015
Introduction Il est necessaire d’etablir la balance entre les apports operatoires reels et les in... more Introduction Il est necessaire d’etablir la balance entre les apports operatoires reels et les inconvenients de mise en œuvre des technologies modernes dans les blocs operatoires. L’objectif de ce papier etait de tirer un premier bilan de l’utilisation de l’imagerie 3D peroperatoire (O-Arm, Medtronic™, Louisville, CO) en chirurgie orthopedique peripherique, non rachidienne. Patients et methode . Six patients ont ete inclus, cinq tumeurs pelviennes malignes et un cal vicieux du bassin. Resultats Toutes les procedures tomodensitometriques ont ete poursuivies jusqu’a leur terme, sans difficultes. La navigation a du etre interrompue deux fois. L’encombrement du O-Arm n’a pas empeche le deroulement aise de l’intervention hormis dans un cas no 5 ou le scanner a du etre deplace et reinstalle durant l’intervention. Les longueurs d’intervention habituelles avec ce type de patients ne suggerent pas d’allongement lie a la mise en œuvre de ces techniques. Les irradiations propres a l’utilisation du O-Arm varient de 450 a 1125 mGrey.cm (dose length product [DLP]). Les procedures chirurgicales ont pu etre menees conformement aux planifications preoperatoires. Les cinq resections sont R 0. Elles auraient pu etre realisees sans assistance d’imagerie 3D ou de navigation, mais ces elements ont apporte un controle peroperatoire total. Cette securisation concernait le positionnement des coupes osseuses assurant la securite carcinologique malgre des conditions locales delicates, le positionnement des implants ou la qualite de la reduction. Discussion Cette etude preliminaire montre que ce systeme d’imagerie 3D peroperatoire peut etre mis en œuvre lors d’interventions orthopediques majeures non rachidiennes confirmant le benefice attendu en termes de controle. Elle apporte des informations en temps reel sur les phases de resection comme sur celles de reconstruction. Les inconvenients operatoires potentiels apparaissent negligeables. Conclusion Les resultats preliminaires autorisent la poursuite de son utilisation et montrent que le developpement de ces methodes est souhaitable et justifie.
Report an unusual presentation of Erdheim-Chester disease revealed by a severe hypothalamic syndr... more Report an unusual presentation of Erdheim-Chester disease revealed by a severe hypothalamic syndrome due to a hypothalamic infiltration and a review of the literature. A 28-year-old man was admitted for a previous three-month history of asthenia, weight loss, and polyuria-polydipsia. Magnetic resonance imaging on gadolinium T1-weighted sequence revealed a contrast-enhancing hypothalamic mass extending to the floor of the fourth ventricle. Cerebrospinal fluid examination was not suggestive of a germinal lesion. Lung nodules were found on thoracic CT-scan but due to their small size, brain stereotactic biopsies were required. Histological examination revealed a diffuse polymorphic inflammatory infiltrate including numerous foamy histiocytes which displayed large eosinophilic CD68-positive, CD1a-negative cytoplasms, and collagen deposition, characteristic of Erdheim-Chester disease. Despite symptomatic and etiologic treatment, death occurred within twelve months. Erdheim-Chester diseas...
Prospective memory (PM) can be described as the ability to remember to complete a future task. PM... more Prospective memory (PM) can be described as the ability to remember to complete a future task. PM tasks can be event-based (respond when an event occurs) or time-based (respond at a specific time). The current study compared these two types of PM tasks. Students from Illinois State University participated in return for class credit. Participants were asked to complete a prospective memory task embedded in an ongoing task. We compared event- and time-based prospective memory under focal (similar cues across ongoing and PM tasks) and non-focal (different cues across ongoing and PM tasks) conditions. An analyzation of both category-based prospective memory and time-based prospective memory will give insight to cognitive processes in the completion of these types of intended tasks. We expect higher performance for event-based PM overall and higher performance with focal than non-focal tasks, showing that the overlap in cues aids performance
Revue de Chirurgie Orthopédique et Traumatologique, 2018
Plusieurs types d'instabilité atlanto-axoïdienne peuvent justifier une fixation chirurgicale. L'a... more Plusieurs types d'instabilité atlanto-axoïdienne peuvent justifier une fixation chirurgicale. L'arthrodèse instrumentée par vissage des masses latérales de C1 et des isthmes de C2 décrite par Harms est une technique exigeante mais qui permet une stabilisation pérenne. Elle est associée à des complications nerveuses ou vasculaires liées à la configuration des rapports anatomiques locaux. Les technologies de navigation per-opératoire permettent d'améliorer la précision technique. Cette série présente 11 cas d'arthrodèse C1C2 type Harms réalisées sous navigation et contrôle peropératoire 3D. Toutes les procédures ont pu être menées à leur terme avec une disposition adéquate des implants. Aucun événement indésirable propre à l'arthrodèse n'est survenu dans la période peri-opératoire. Aucune effraction corticale n'a été constatée sur le contrôle tomodensitométrique cone bean (Oarm ®) réalisé en fin d'intervention. Les difficultés techniques et les risques des arthrodèses C1C2 type Harms conduisent à utiliser les contrôles d'imagerie 3D peropératoires lorsqu'ils sont disponibles.
Revue de Chirurgie Orthopédique et Traumatologique, 2016
Note de technique Apport de l'imagerie 3D naviguée en chirurgie de résection tumorale osseuse pel... more Note de technique Apport de l'imagerie 3D naviguée en chirurgie de résection tumorale osseuse pelvienne ଝ
Open Access Rheumatology: Research and Reviews, 2019
Background and objective: There is absence of data on the prevalence of osteoporosis before corre... more Background and objective: There is absence of data on the prevalence of osteoporosis before corrective surgery of the lumbar spine. We do not know the impact of bone assessment before corrective spine surgery, regarding the prevalence of osteoporosis, risk factors for osteoporosis, and prescription of osteoporotic treatment. Our objective was to evaluate the impact of assessment of bone status before corrective surgery of the lumbar spine. Methods: This retrospective study was conducted over a period of 30 months. Patients included were over 50 years old and had been referred to rheumatology consultation prior to corrective surgery of the lumbar spine with osteosynthesis, for scoliosis or spondylolisthesis. Assessment of bone status consisted in looking for risk factors for osteoporotic fracture, performing bone densitometry with the calculation of TBS (trabecular bone score) and the possible introduction of treatment for osteoporosis. Data were collected on complications related to bone fragility during follow-up. Results: Twenty-eight patients with a median age of 71.2 years (55.5-84.8) were included; 89% were women. T score was <−2.5 in 14.3% (4/28) and −1 to −2.5 in 42.9% (12/28) on at least one of the three sites analyzed. Fifty percent of patients had a TBS <1.2, a history of more than four falls per year, a duration of more than 20 s in the Timed Up and Go Test, and/ or sedation treatment. Vitamin-calcium supplementation and treatment for osteoporosis were prescribed in 71.4% and 17.8% of cases, respectively. During follow-up, 3 patients had one or more osteoporotic vertebral fractures and 4 patients had loosening of implanted devices. Conclusion: Despite a low prevalence of densitometric osteoporosis and therapeutic management, one in four patients had a bone complication, suggesting the superiority of TBS as an indicator of bone status.
Orthopaedics & traumatology, surgery & research : OTSR, 2018
Several types of atlantoaxial instability can justify surgical fixation. The instrumented fusion ... more Several types of atlantoaxial instability can justify surgical fixation. The instrumented fusion procedure described by Harms with screw fixation of the C1 lateral masses and C2 pedicles is a demanding technique that provides lasting stabilization. However, it has been associated with nerve and vascular complications due to the local anatomical configuration. Surgical navigation systems can help improve the procedure's accuracy. We describe a series of 11 cases of C1C2 Harms fusion performed with surgical navigation and intraoperative 3D imaging checks. All procedures were carried out completely with satisfactory implant placement. There were no adverse events related to the procedure during the peri-operative period. No cortical breach was detected using cone-beam CT at the end of the procedure. The technical challenges and risks associated with C1C2 Harms fusion have led to the use of 3D intraoperative imaging systems, when available.
Spinal meningiomas are slow-growing intradural-extramedullary tumors. They are usually associated... more Spinal meningiomas are slow-growing intradural-extramedullary tumors. They are usually associated with good outcomes. However, there are few descriptions of factors predictive of impaired evolution. Our objective was to identify predictive factors of post-operative deterioration as well as outcomes at follow-up. Between 2009 and 2016, 87 patients had surgery for spinal meningioma in our referral center. Clinical presentation, management and outcomes were reported during the post-operative period and at 3-month follow-up. Evaluation was based on post-operative neurological deterioration defined as an increase of at least one point in the McCormick score compared to the status at admission. During the study period, post-operative deterioration occurred in 17 patients (19.5%). Risk factors associated with this deterioration were the absence of pre-operative neurological signs (Relative Risk; RR = 2.38, p = 0.04), an anterior location of the meningioma and a grade 2 meningioma on WHO cl...
Revue de Chirurgie Orthopédique et Traumatologique, 2015
Introduction Il est necessaire d’etablir la balance entre les apports operatoires reels et les in... more Introduction Il est necessaire d’etablir la balance entre les apports operatoires reels et les inconvenients de mise en œuvre des technologies modernes dans les blocs operatoires. L’objectif de ce papier etait de tirer un premier bilan de l’utilisation de l’imagerie 3D peroperatoire (O-Arm, Medtronic™, Louisville, CO) en chirurgie orthopedique peripherique, non rachidienne. Patients et methode . Six patients ont ete inclus, cinq tumeurs pelviennes malignes et un cal vicieux du bassin. Resultats Toutes les procedures tomodensitometriques ont ete poursuivies jusqu’a leur terme, sans difficultes. La navigation a du etre interrompue deux fois. L’encombrement du O-Arm n’a pas empeche le deroulement aise de l’intervention hormis dans un cas no 5 ou le scanner a du etre deplace et reinstalle durant l’intervention. Les longueurs d’intervention habituelles avec ce type de patients ne suggerent pas d’allongement lie a la mise en œuvre de ces techniques. Les irradiations propres a l’utilisation du O-Arm varient de 450 a 1125 mGrey.cm (dose length product [DLP]). Les procedures chirurgicales ont pu etre menees conformement aux planifications preoperatoires. Les cinq resections sont R 0. Elles auraient pu etre realisees sans assistance d’imagerie 3D ou de navigation, mais ces elements ont apporte un controle peroperatoire total. Cette securisation concernait le positionnement des coupes osseuses assurant la securite carcinologique malgre des conditions locales delicates, le positionnement des implants ou la qualite de la reduction. Discussion Cette etude preliminaire montre que ce systeme d’imagerie 3D peroperatoire peut etre mis en œuvre lors d’interventions orthopediques majeures non rachidiennes confirmant le benefice attendu en termes de controle. Elle apporte des informations en temps reel sur les phases de resection comme sur celles de reconstruction. Les inconvenients operatoires potentiels apparaissent negligeables. Conclusion Les resultats preliminaires autorisent la poursuite de son utilisation et montrent que le developpement de ces methodes est souhaitable et justifie.
Report an unusual presentation of Erdheim-Chester disease revealed by a severe hypothalamic syndr... more Report an unusual presentation of Erdheim-Chester disease revealed by a severe hypothalamic syndrome due to a hypothalamic infiltration and a review of the literature. A 28-year-old man was admitted for a previous three-month history of asthenia, weight loss, and polyuria-polydipsia. Magnetic resonance imaging on gadolinium T1-weighted sequence revealed a contrast-enhancing hypothalamic mass extending to the floor of the fourth ventricle. Cerebrospinal fluid examination was not suggestive of a germinal lesion. Lung nodules were found on thoracic CT-scan but due to their small size, brain stereotactic biopsies were required. Histological examination revealed a diffuse polymorphic inflammatory infiltrate including numerous foamy histiocytes which displayed large eosinophilic CD68-positive, CD1a-negative cytoplasms, and collagen deposition, characteristic of Erdheim-Chester disease. Despite symptomatic and etiologic treatment, death occurred within twelve months. Erdheim-Chester diseas...
Prospective memory (PM) can be described as the ability to remember to complete a future task. PM... more Prospective memory (PM) can be described as the ability to remember to complete a future task. PM tasks can be event-based (respond when an event occurs) or time-based (respond at a specific time). The current study compared these two types of PM tasks. Students from Illinois State University participated in return for class credit. Participants were asked to complete a prospective memory task embedded in an ongoing task. We compared event- and time-based prospective memory under focal (similar cues across ongoing and PM tasks) and non-focal (different cues across ongoing and PM tasks) conditions. An analyzation of both category-based prospective memory and time-based prospective memory will give insight to cognitive processes in the completion of these types of intended tasks. We expect higher performance for event-based PM overall and higher performance with focal than non-focal tasks, showing that the overlap in cues aids performance
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