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International audience; We performed two experiments to investigate how monocular vision and a monocular generalized reduction in vision (MRV) impact driving performance during racing. A total of 75 visually normal students or professional racing drivers, were recruited for the two experiments. Driving performance was evaluated under three visual conditions: normal vision, simulated monocularity and simulated monocular reduction in vision. During the driving scenario, the drivers had to detect and react to the sudden intrusion of an opponent's racing car into their trajectory when entering a turn. Generalized Linear Mixed Models (GLMMs) and ANOVA were then used to explore how monocular vision and monocular reduction in vision affect drivers' performance (crash and reaction time) while confronting them with critical situations. The results show that drivers under monocular condition are from 2.1 (95% CI 1.11-4.11, p = .024) to 6.5 (95% CI 3.91-11.13; p = .0001) times more likely to collide with target vehicles compared with their baseline (binocular) condition, depending on the driving situation. Furthermore, there was an average increase in reaction time from 64 ms (p = .029) to 126 ms (p = .015) under monocular condition, depending on the critical driving situation configuration. This study objectively demonstrates that monocularity has a significant impact on driving performance and safety during car racing, whereas performance under monocular reduction in vision conditions is less affected.

The Federation Internationale de l’Automobile (FIA) is the world governing body of motor sport. In motor sport, anti-doping policies for international competitions were implemented in 2008 and the ...

International audience; We report the ability of amino- and carboxyl-modified MCM-41 mesoporous silica nanoparticles (MSN) to deliver gene in vivo in rat Achilles tendons, despite their inefficiency to transfect primary tenocytes in culture. We show that luciferase activity lasted for at least 2 weeks in tendons injected with these MSN and a plasmid DNA (pDNA) encoding the luciferase reporter gene. By contrast, in tendons injected with naked plasmid, the luciferase expression decreased as a function of time and became hardly detectable after 2 weeks. Interestingly, there were neither signs of inflammation nor necrosis in tendon, kidney, heart and liver of rat weekly injected with pDNA/MSN formulation during 1.5 months. Our main data concern the acceleration of Achilles tendons healing by PDGF-B gene transfer using MSN. Biomechanical properties and histological analyses clearly indicate that tendons treated with MSN and PDGF gene healed significantly faster than untreated tendons and those treated with pPDGE alone.

Resume Nous rapportons le cas d’une femme de 47 ans qui presentait une instabilite glenohumerale multidirectionnelle de direction anterieure predominante. Apres reeducation, la patiente a ete traitee chirurgicalement par une butee coracoidienne anterieure de type Latarjet. Au deuxieme jour postoperatoire, un scanner de controle montrait une luxation glenohumerale posterieure. La patiente a ete reoperee avec la mise en place d’une butee iliaque posterieure. Au dernier recul clinique de six ans, les mobilites etaient normales et le resultat fonctionnel juge excellent selon les scores d’evaluation clinique. Les auteurs rappellent les hypotheses etiopathogeniques de l’instabilite multidirectionnelle et discutent la multiplicite des traitements proposes. Le cas rapporte illustre la difficulte de prise en charge diagnostique et therapeutique d’une instabilite multidirectionnelle d’epaule. L’examen effectue sous anesthesie generale, montrait une laxite posterieure predominante, alors que, paradoxalement, la patiente presentait des luxations antero-internes predominantes. L’originalite de ce cas reside dans l’apparition d’une luxation posterieure d’epaule, complication immediate inhabituelle apres une butee anterieure. Dans le cas d’une instabilite multidirectionnelle avec des lesions osseuses de passage, les auteurs recommandent la mise en place d’une butee dans le sens predominant de l’instabilite. L’examen sous anesthesie generale preoperatoire peut permettre de comprendre les causes d’une instabilite residuelle postoperatoire, necessitant parfois une chirurgie stabilisatrice complementaire.

The second generation of metal-on-metal prostheses appeared at the end of the 1980’s as a serious alternative to metal on polyethylene bearing couples. Short-term clinical results were promising; however certain questions remain concerning clinical, radiological and biological aspects. Release of chromium and cobalt from the bearing couple is one of these aspects. The aim of this study is to analyse the results of a series of 97 cemented total hip prostheses comprising a titanium femoral stem and the Metasul® metal-metal bearing couple. Mean follow-up was nine years (7–12 years). Complications were marked by 12 revisions, out of which two were for recurrent early dislocations, eight for clinical and radiological failure, and two for worrying radiological alterations. During these revisions, we observed a serious infiltration of metal debris four times, leading to an alternative strategy using an alumina-alumina bearing couple. Three more revisions are planned for rapidly evolving radiological alterations. Thirty implants showed radiological signs of preoccupying deterioration on the acetabular side. Eight segmentary femoral osteolysis have been observed. Twelve patients suffer from recurrent subluxation. Concerning the global evolution of metal serum levels, cobalt remains stable after five years. The values are three to four times above those of a non-exposed subject, but largely below toxic ratios. The evolution of serum chromium levels is similar to cobalt. Implantation of two prostheses in one same patient leads to significant increase in serum metal ratios. This series raises questions concerning the reliability of the metal-on-metal bearing couple. Osteolysis is an unsolved problem. Today, cemented fixation is debatable although this series doesn’t allow this parameter to be held directly responsible. Nothing points to any shortcomings concerning the taper fixation or the metallurgy of the femoral stem. The study of the serum metal levels seems a good indicator of the impingement situations and the functioning of the bearing couple.

Usual interbody cages at the lumbar spine are made of titanium or carbon fiber-polyetheretherketone (PEEK). Pure PEEK cages have more recently been proposed for its lower elasticity modulus. The goal of our study was to investigate a series of patients with circumferential fixation using anterior PEEK cages for degenerative lumbar spine disorders with a specific interest in the local lordosis. Fifty-seven consecutive patients aged 54.6 years (29 to 75) were reviewed. The level of arthrodesis varied from L2L3 to L5S1. The clinical status and the radiologic variations in local lordosis at the level of arthrodesis were measured. Decrease in lordosis at follow-up was tested in a multivariate analysis regarding age, obesity, spinal level, bone graft amount, type of posterior instrumentation, postoperative lordosis increase, and cage height. The average follow-up was 5.7 years (4 to 8). Clinical outcomes were excellent or good in 49 cases. Fusion was definite in 56 cases. Although 47 patients had no change in lordosis after surgery, 10 cases showed lordosis increase (8.2 degrees; 5 to 12). At follow-up, local lordosis decreased in 13 cases (5.6 degrees; 4 to 8). The linear model was significant (P0.001; R=0.590) showing that loss in lordosis was related with postoperative lordosis increase (P=0.01), cage height (P0.001), posterior instrumentation rigidity (P=0.026), age (P=0.047), and low level (P=0.013). Lumbar circumferential arthrodesis using PEEK cages provided good clinical results and fusion rate. However, lordosis correction was not maintained at follow-up, especially at lower levels, using high cages, in older patients, and when associated with a rigid primary posterior instrumentation. Regarding the last point, this is likely that the order of the instrumentation (posterior first, then anterior) played a role in the loss of lordosis in case of rigid posterior fixation.

Lumbosacral orientation in the sagittal plane is of utmost importance, as it plays a critical role in the function of the spine and the hip joints. Equilibrium of the trunk influences the tridimensional orientation of the acetabulum and the functional range of motion of the hips. Each patient is characterized by a “morphological” parameter named incidence angle; its sagittal balance is the consequence of a postural adaptation for other functional parameters (pelvic tilt, sacral slope, lumbar lordosis, acetabular sagittal tilt, functional anteversion). Understanding variations of the sacral slope on lateral pelvic X-rays is essential for planning total hip arthroplasty and identifying patients at risk of impingement, as lumbosacral posture influences functional anteversion of the acetabulum. Posterior pelvic version as in sitting position (sacral slope decrease) is linked to the increase of the functional acetabular anteversion. Anterior pelvic version as in standing position (sacral slope increase) is linked to the decrease of the functional acetabular anteversion.

Local post-traumatic kyphosis may impair spinal sagittal balance and result in severe disability. The goal of this study is to evaluate posterior closing wedge osteotomy at the level of injury, by comparing thoracolumbar (T12-L1) and lumbar (L2-4) spinal levels. Thirteen consecutive patients had surgery in an average 13 months after the initial injury. There were 8 thoracolumbar and 5 lumbar deformities. Nine patients already had posterior fixation. Eight patients had preoperative neurological deficits. Sagittal correction was assessed in terms of regional angulation (RA) and effective regional deformity (ERD), which was defined as the difference between the actual RA and the physiological RA for the level. The average follow up was 2.1 years. The average RA passed from 43.8 degrees (31 to 55) to 2.2 degrees (-5 to 7) after surgery. It was 5.3 degrees (-4 to 12), at follow-up. RA and surgical correction were not significantly different between thoracolumbar and lumbar groups. The average ERD was 47.2 degrees (24 to 66) preoperatively and 8.6 degrees (-5 to 37) at follow-up. The ERD passed from 41.8 degrees (24 to 54) to 0.5 degrees (-5 to 6) in the thoracolumbar group, and from 55.8 degrees (50 to 66) to 21.6 degrees (17 to 37) in the lumbar group. The ERD was significantly different initially (P=0.014) and after surgery (P=0.06). The anatomical result was complete in the thoracolumbar group, because the correction of the deformity at this level does not require more than correction of the vertebral body kyphosis. On the contrary, due to adjacent disc damage, the technique did not fully restore the physiological regional lordosis at lower levels.

Arthrodesis using interbody cages has demonstrated high fusion rates. However, permanent cages are exposed to stress-shielding, corrosion, and may require explanation when necessary. Polylactic acid (PLA) bioresorbable cages are developed for avoiding these problems, but significant tissue reaction has been reported with 70/30 PLDLLA in some preclinical animal studies. The objective was to evaluate 96/4 PLDLLA cages in a sheep model over 3 years. Sixteen sheeps underwent one level anterior lumbar interbody fusion using 96/4 PLDLLA cages, filled and surrounded with cancellous bone graft from the iliac crest. Six groups of three animals were killed after 3, 6, 9, 12, 24, and 36 months. Harvested lumbar spine had radiographic, MRI, and CT evaluation and histological analysis. Histological results: cage swelling and slight signs of fragmentation associated to fibrocartilaginous tissue apposition at 3 months; bone remodeling around the cage with direct apposition of the mineralization front at 6 months; active cage degradation and complete fusion around the cage at 9 months; cage fragmentation and partial replacement by bone tissue at 12 months; bone bridges in and around the cage at 24 months; full resorption and intervertebral fusion at 36 months. Radiological results: partial arthrodesis at 3 months; definite peripheral arthrodesis at 6 months; similar aspect at 9 months; significant cage resorption at 12 months; definite inner and outer fusion at 24 months; complete cage resorption and calcification at the location of the cage at 36 months confirmed histological observations. Radiographic, CT scan, MRI, and histological data were consistent for showing progressive resorption of 96/4 PLDLLA, interbody fusion, and bone remodeling, with no significant signs of local intolerance reaction. These results are promising and suggest further development of 96/4 PLDLLA cages.

When surgically treated, pelvic-ring deformities due to post-traumatic malunions in adults usually require invasive three-stage (prone/supine/prone or supine/prone/supine) procedures. A standardised two-stage prone/supine procedure was developed by the authors. Technical points and first clinical results are presented. Malunuions related to Tile B and C types of fracture were successfully corrected.

RESUME Les traumatismes medullaires touchent en France, environ 2000 personnes par an. Il s’agit le plus souvent d’hommes jeunes, victimes d’un accident de la voie publique, presentant un traumatisme du rachis cervical. La prise en charge, immediate et pre-hospitaliere, est fondamentale car elle engage le pronostic vital et le pronostic fonctionnel. Le diagnostic de lesion medullaire doit etre systematiquement suspecte et le rachis immobilise. L’examen neurologique initial est fondamental. Les gestes initiaux visent a :—maintenir une pression arterielle moyenne superieure a 80mmHg,—assurer une bonne ventilation du patient,—le rechauffer et eviter l’hyperglycemie. Le transport doit etre rapide et oriente vers un centre specialise dans la prise en charge de ces patients.

Resume Les dossiers de 24 pieds operes de sequelles de fractures trans-thalamiques du calcaneum chez des patients âges en moyenne de 42 ans ont ete revus retrospectivement avec un recul moyen de 36 mois afin d’analyser les lesions retrouvees et d’en degager les principes permettant une prise en charge optimale tant au stade aigu qu’au stade sequellaire. Tous les patients ont eu un examen clinique, podoscopique et un bilan radiographique. L’evaluation fonctionnelle a ete faite en utilisant le score de Kitaoka. Avant la prise en charge, tous les patients se plaignaient de douleurs, la mobilite moyenne comparative de l’articulation sous-talienne etait de 30 %, la desaxation frontale moyenne de l’arriere-pied de 6 en valgus et le score fonctionnel moyen de 31/100. Les consequences de la deformation architecturale du calcaneum (accourcissement, perte de hauteur et elargissement) ne se limitaient pas a l’arthrose sous-talienne (23 cas), mais comprenaient aussi des douleurs et une gene au chaussage par arthrose calcaneo-cuboidienne (8 cas), conflit sous-malleolaire externe (15 cas), luxation ou fissure des tendons fibulaires (12 cas), syndrome du canal tarsien (3 cas) et esquille plantaire (2 cas). Le traitement de ces sequelles a consiste en la realisation, de facon associee ou separement, de 23 arthrodeses sous-taliennes dont une associee a une arthrodese calcaneo-cuboidienne, de 7 resanglages des tendons fibulaires, de 3 neurolyses du nerf tibial posterieur, de 2 resections d’esquilles plantaires, de 14 resections de l’ecaille externe et de 2 osteotomies d’abaissement de la grosse tuberosite du calcaneum pour des douleurs de chaussage. Apres traitement, le score moyen de Kitaoka etait de 81,7/100. Neuf patients se plaignaient toujours de douleurs dont trois pour une luxation des tendons fibulaires negligee. Trois arthrodeses sous-taliennes ont necessite une reprise chirurgicale pour non consolidation. Le perimetre de marche etait superieur a 3 000 metres pour 18 patients. Les resultats de cette serie et ceux rapportes par la litterature, nous poussent aujourd’hui a insister sur l’importance, au stade sequellaire, de l’examen clinique du patient. En effet, il permet un bilan lesionnel complet et le depistage de l’ensemble des lesions susceptibles de se demasquer secondairement. L’arthrodese de l’articulation sous-talienne sera privilegiee par rapport a la reaxation de l’arriere-pied et sera, si necessaire, associee au traitement de tous les conflits. La varisation de la grosse tuberosite posterieure n’est pas en soit genante car elle s’accompagne le plus souvent d’une translation externe compensatrice du fragment corticothalamique. La resultante est un appui axe sans necessite d’osteotomie de valgisation.

Gorham-Stout disease is defined as a spontaneous, massive, and nonfamilial idiopathic osteolysis. The diagnosis is based essentially on radiological and histological findings. Biopsy reviews always reveal excessive intraosseous nonmalignant proliferation of small vessels, which results in bone resorption and may extend to adjacent bones and soft tissues. These lesions are progressively replaced by extensive fibrosis. Since its first description in 1955, there is still controversy about its prognosis, etiology, and treatment. A case of Gorham-Stout disease, located on the right pelvis, is reported with 50 years of clinical and radiographic follow-up, in a man who has never been treated. To date, this is the longest documented case report of the disease and its rare natural history. It demonstrates that after a variable time of evolution, the massive osteolysis is able to undergo spontaneous arrest and that the lesions may remain stable during several decades. Besides, no reossification was observed, even after 37 years of disease quiescence. Based on a large review of the literature, the authors then discuss the prognosis, etiopathology, and different therapeutic options available to halt the progression of the osteolysis.

Fernez-Bertaud Olivier, Rolland Éric, Saillant Gérard. Résultat à très long terme du traitement chirurgical des épicondylites. À propos de 28 cas. In: Les Cahiers de l'INSEP, n°35, 2005. Les sports de raquette. Données scientifiques et méthodologiques. Applications pour l'entraînement. pp. 81-92.

Variations of acetabular anteversion measured at the level of the diameter of the acetabulum according to the tilt of the pelvis are known. But the values of this anteversion at other levels of the acetabulum, near the roof or near the obturator foramen, are unknown. Attracted by the very changeable morphology of the acetabular cover, we studied the caudal, central, and cranial acetabular anteversion of 12 pelvises in four positions of dorsal-ventral inclination. The caudal, central, and cranial acetabular anteversion diminished with the ventral tilt of the pelvis. The anteversions also diminished from the caudal part of the acetabulum to the cranial part, whatever the inclination of the pelvis. These notions represent a reference that, once completed with clinical studies of healthy volunteers and patients presenting an anomaly of the acetabulum cover, will enable researchers to define threshold values of normal and pathological conditions.

The criteria for acetabular cup positioning during total hip replacement are a matter of considerable discussion, particularly with regards to the optimal degree of anteversion. "Anatomical anteversion" is defined in the transverse plane, and "surgical anteversion" in the sagittal plane. Computed tomography measurements of anteversion are characteristic of a given transverse section plane and fail to take into account the position of the pelvis. We suggest a simple method for evaluating acetabular cup position in both the transverse and sagittal planes during standing and sitting. By shedding new light on the relationships between the pelvis and the spine, this method may help to understand some cases of impingement, instability or abnormal wear.

Background It has been suggested that the dose of intravenous morphine used during postoperative titration is not modified by aging. The authors therefore studied morphine requirements in patients undergoing total hip replacement. Methods Intravenous morphine titration was administered as boluses, then subcutaneous morphine was administered every 4 h over 24 h. Pain was assessed by use of the visual analog scale (0 to 100), and the threshold required to administer morphine was 30. Young and elderly (> or =70 yr old) patients were compared. Data are mean +/- SD or odds ratio (OR) [95% CI]. Results Two hundred twenty-four patients (68%) were young and 105 (32%) were elderly. The initial visual analog scale was not significantly different between groups. The dose of intravenous morphine in the postanesthesia care unit was not significantly different between young and elderly patients (0.15 +/- 0.11 vs. 0.14 +/- 0.10 mg/kg, P = NS), in contrast to the dose of subcutaneous morphine (0.18 +/- 0.18 vs. 0.11 +/- 0.11 mg/kg, P < 0.001) in the ward. Only severe pain (visual analog scale of 70 or greater; OR, 10.5 [4.5-24.8]) was significantly associated with a high dose (greater than 0.15 mg/kg) of intravenous morphine, whereas severe pain (OR, 2.5 [1.6-4.0]), age less than 60 yr (OR, 2.3 [1.4-3.8]), and absence of a nonsteroidal antiinflammatory drug (OR, 1.9 [1.2-3.1]) were significantly associated with a high dose (greater than 0.12 mg/kg) of subcutaneous morphine. Conclusions The dose of intravenous morphine during titration is not modified in elderly patients, in contrast to the dose administered subcutaneously over a prolonged period.

Background Degenerative or traumatic tendon injuries are extremely common but often heal poorly, not restoring the normal function of the injured tissues. Gene transfer could improve the repair process, by permitting local production of therapeutic substances, e.g. growth factors. Methods and results Injection of a plasmid carrying the lacZ marker gene was performed into the Achilles tendons of rat and mouse, and the patellar tendons of rabbit. At 48 h, transduced cells were found in the injected zones of the tendons but represented a minority of the tendon cells. A kinetics study in rats permitted observation of a gradual decrease with time in the β-gal-expressing cell number; at day 42 no more gene expression was detected. Noteworthy, no inflammatory reaction was observed. We then investigated whether electrotransfer could improve gene transfer efficacy in rat tendon by delivering in situ electric pulses after DNA injection. Gene transfer was improved at best by ≈50% under certain electrical conditions (200 V for 10 ms or 1200 V for 100 µs). Finally, multiple injections of plasmid permitted an increase in the number of transduced cells by ≈400%. Conclusions In situ injection of naked DNA into tendons is a very simple technique that permits delivery of genes with a duration of expression sufficient for clinical application aimed at modulating healing or restoration of a degenerative tendon. Despite a low transfer efficiency, this method should be compatible with clinical applications aimed at delivering therapeutic substances acting at low concentration. Copyright © 2003 John Wiley & Sons, Ltd.

We report a case of rotatory atlantoaxial dislocation due to a rugby injury in an adult. The patient presented with torticollis 4 weeks after the injury. The neurological evaluation was normal. Reduction proved difficult to obtain and required 10 days of skull traction followed by gentle manipulation. After reduction, dynamic cervical radiographs showed no instability and magnetic resonance imaging (MRI) confirmed that the transverse ligament was intact. After 6 weeks of immobilization in a Minerva jacket, a dynamic rotatory computed tomography (CT) scan confirmed that the atlantoaxial joint was stable. Such cases of atlantoaxial joint dislocation in adults treated by traction after a considerable delay are rare. In our patient, demonstration by MRI that the transverse ligament was intact led to the decision to use conservative therapy, which proved successful.

Anterior lumbar spine approaches may be indicated for fusion in degenerative lumbar spine disorders or to fill discal and bone gaps after fracture reduction. We present an anterior extraperitoneal approach applicable to any discal and vertebral levels from T12 to S1. The anatomic study, based on 25 cadavers, highlights retroperitoneal dissection principles for easy kidney and duodenopancreatic mobilisation and direct left anterior access to the entire lumbar spine. We established a precise description of the lumbar veins and the anastomoses between the left renal vein and hemiazygos system, in order to define different topographic and anatomic factors related to safe and easily reproducible approaches for cage or graft implementation. Independent of the level and previous intraperitoneal surgery, lumbar spine access with this approach safeguards the kidney, ureter, spleen, hypogastric plexus and duodenopancreatic system. Regarding operating time, blood-loss and possibilities for freshening and grafting, this technique seems an effective counterbalance to the difficulties and complex technology of endoscopic approaches. The clinical study includes our first 42 cases in traumatic and degenerative lesions. Avoiding the neurologic or hemorrhagic risk inherent in classical posterior lumbar interbody fusion (PLIF) techniques, it can be considered as a reasonable and valid alternative. This technique could be used in the near future for mini invasive discal prosthesis insertion.

Intraoperative ultrasonography is recommended for operations on the thoracolumbar spine to complement the information provided by standard X-ray, intensifier screen or myelography. There are no unanimates opinions concerning the impaction or exeresis of these fragments. The aim of this study was to show the advantages of intraoperative ultrasonography for anatomic determination and control of the maneuvers used. This study included 46 cases with fractures from T11 to L2. Ultrasonography was performed during the intraoperative reduction provided by the installation and the pedicular instruments. The authors stress the limits of the anatomic and geographic determination, as well as tilting of the fragments because of the size of the ultrasonographic head. The quality of the exeresis may be falsely interpreted in the presence of fragments with a section of less than 4 mm, lateralized, double fragments or in the presence of massive intraoperative haemorrhage. Analysis of the impaction results is more complicated because all of these fragments displaced themselves secondarily. The ligamentum communis vertebralis posterior has no anatomical containing role. The tilting before the impaction and the state of the overlying intervertebral disk represent essential factors for failures. Ultrasonography is better than intraoperative myelography. Nevertheless, it still needs to be complemented by intraoperative profile X-rays and a very precise preoperative CT scan of the intervertebral disk lesions analysis of complicated cases (fragments with residual pedicular attachments--type A 3.1.2.; T-like fractures--type A 3.2.1.).

Pelvic osteotomies were developed to increase or restructure the acetabular surface. Periacetabular osteotomies are considered the most difficult from the technical point of view and necessitate sufficient residual cartilaginous surface. Juxta-acetabular osteotomies avoid major disorganization of the pelvic framework and allow easier reorientation of the acetabulum. The authors present a technical variant that preserves the entire posterior column, as in the Ganz osteotomy. The effects on the vascularisation of the periacetabular region are strictly the same and there is no necrosis of the subchondral bone. This osteotomy is easier to perform, because of a single positioning associating two simultaneous approaches. The osteotomies are rectilinear and easy to check peroperatively by fluoroscopy thanks to this positioning. Another valuable aspect of this double approach consists of very easy correction of “automatic” unwanted retroversion due to the lowering of the acetabular roof. This unintended displacement is rarely reported in the literature, despite its anatomic evidence in 3-dimensional CT-scan reconstructions for pre- and peroperative evaluation.

STUDY DESIGN The utility of the Tokuhashi score was assessed in a retrospective study in 71 patients with vertebral metastases. OBJECTIVES To study the importance of the site of the primary tumor as a parameter in the preoperative prognostic Tokuhashi score. SUMMARY OF BACKGROUND DATA A preoperative score composed of six parameters, each rated from zero to two, has been proposed by Tokuhashi for the prognostic assessment of patients with metastases to the spine. METHODS Seventy-one patients with vertebral metastases were studied. There were 34 cases of thyroid cancer metastases, 28 cases of renal cancer metastases, and nine cases of metastases of unknown origin. In each patient, a local and a systemic tumor search were performed. Patients were divided into groups based on the primary site of the tumor, and each group was analyzed separately. RESULTS In cases of vertebral metastases of thyroid cancers, surgery to excise single metastases was found to provide good results, as was palliative surgery of multiple metastases. Vertebral metastases of renal tumors were rarely single, and the results of palliative surgery were less satisfactory. Vertebral metastases of unknown primary tumors had a poor outcome, regardless of whether surgery was excisional or palliative. The median survival period in patients with metastases of unknown primary tumors was significantly shorter than that in patients with renal or thyroid cancer metastases. CONCLUSION The Tokuhashi preoperative score is successful as a prognostic tool. However, it attributes the same one-point rating to metastases of renal cancer and to those of unknown primary tumors. In the case of metastases of unknown primary tumors, this rating is too high and should be reduced to 0.

The deformations and stresses acting on the acetabular rim have not been very precisely documented. The authors present a study based on an experimental simulation of hip loading with anatomic correlations. 122 dissections were performed in order to define the anatomic aspect of the roof (and especially of Byers's “area 17”) and the intermediate area between the anterior and posterior acetabular cornua. Ten fresh cadavers were tested on the lines of previous studies on monopodal or bipodal loading. An extensometric study was performed with special attention to the transverse acetabular ligament, supra-acetabular area and obturator foramen. The area 17 of Byers is a transitional zone and the mobility of the posterior cornu is 3 times that of the anterior cornu. Resection of the acetabular ligament modifies the displacement of the posterior cornu under loading but has no influence on deformation of the oburator foramen. The biomechanical behavior of the acetabular roof in the standing position is influenced by the conditions of monopodal or bipodal loading and by femoral rotation, but a tendency to extrusion was constantly noted.

Neurologically complicated trauma at the lumbar spine mostly involves vertebral fracture due to high-energy mechanisms. Here, an unusual case of lumbar spine trauma with neurologic deficit is reported corresponding to an acute traumatic lumbar disk herniation. This rare type of injury has not been well documented previously. MRI aspect and immunohistochemical features of the disk lesion are presented. Specific mechanisms of injury during contact sports in this case are discussed.

Retroperitoneal pelvic tumours are rare and their surgical approach is challenging. Various surgical approaches have been proposed. We present here an original mini-invasive anterior retroperitoneal approach the pelvic retroperitoneum, which was successful in a 26-year-old woman who had a benign schwannoma of the left sacral plexus. This technique presents advantages over other techniques that were considered in this case, as the least invasive and safest procedure.

Le remplacement discal constitue un challenge chirurgical et technologique qui a suscite le developpement de plusieurs concepts. Certains considerent le disque comme une articulation peripherique et des implants non contraints, semi-contraints et contraints ont ete mis au point. D’autres solutions alternatives existent pour reconstituer un joint intervertebral. Quels que soient les systemes utilises, les etudes prospectives montrent aujourd’ hui la non-inferiorite du remplacement discal par rapport aux techniques d’arthrodese classiques. Le point essentiel reste la rationalisation des indications et la selection des patients basees sur des elements cliniques et en particulier psychologiques, et sur des donnees d’imagerie et en particulier l’IRM.

Little information is provided in the literature describing an efficient reduction technique for pelvic ring disruption. The aim of this study is to assess the use of the transcondylar traction as a closed reduction technique for vertically unstable fracture-dislocations of the sacro-iliac joint. Twenty-four pelvic ring disruptions were treated with attempted closed reduction followed by percutaneous screw fixation. Transcondylar traction was used as a closed reduction technique. Closed reduction to within 1 cm of residual displacement was obtained in all cases. No incidence of infection, digestive, cutaneous, or vascular complications occurred. We observed secondary displacement in three patients. Correction of the vertical displacement is better achieved when performed within 8 days after the trauma. Two posterior screws and a complementary anterior fixation is typically required to avoid further displacement in case of sacral fractures. However, an open approach should be preferred in both cases of crescent iliac fracture-sacroiliac dislocation and transforaminal fracture associated with peripheral neurological deficit. A vertical sacral fracture should make the surgeon more wary of fixation failure and loss of reduction.

In France, about 2000 people suffer spinal cord injuries each year. Most patients are young men involved in road accidents and most have cervical lesions. Emergency pre-hospital care is crucial, as the lesions are potentially life-threatening and can have devastating functional consequences. The possibility of spinal cord trauma must always be kept in mind, and the spine must be immobilized. The initial neurological examination is extremely important. Initial medical care should target an average systolic blood pressure above 80 mmHg, ensure adequate ventilation, maintain the body temperature over 36 degrees C, and control hyperglycemia. The patient should be transported rapidly to a specialized spinal trauma unit.

No consensus has been reached regarding surgical management of degenerative spondylolisthesis. The optimal type of surgical procedure and surgical indications have not been precisely defined. In order to screen for predictors of outcome, we retrospectively studied patient outcomes after posterior decompression and fusion for isolated lumbar degenerative spondylolisthesis. Twenty-four consecutive patients (age range 50–78 years) underwent primary surgery for isolated lumbar degenerative spondylolisthesis. The surgical procedure consisted of posterior decompression and pedicle screw instrumented fusion using autogeneous bone graft, with or without interbody fusion. Clinical and radiologic status were assessed using the Beaujon functional score and plain AP and lateral radiographs. A multivariate analysis was used to correlate the functional score increase with surgical procedure modifications and preoperative clinical and radiologic features in order to determine which of them led to better results. Eighteen patients completed the evaluation. Six others were lost to follow-up after a minimum of 0.87 years. Combining all the results, the mean follow-up was 2.87 years. The Beaujon score was improved in the 24 patients (P

Degenerative or traumatic tendon injuries are extremely common but often heal poorly, not restoring the normal function of the injured tissues. Gene transfer could improve the repair process, by permitting local production of therapeutic substances, e.g. growth factors.Injection of a plasmid carrying the lacZ marker gene was performed into the Achilles tendons of rat and mouse, and the patellar tendons of rabbit. At 48 h, transduced cells were found in the injected zones of the tendons but represented a minority of the tendon cells. A kinetics study in rats permitted observation of a gradual decrease with time in the beta-gal-expressing cell number; at day 42 no more gene expression was detected. Noteworthy, no inflammatory reaction was observed. We then investigated whether electrotransfer could improve gene transfer efficacy in rat tendon by delivering in situ electric pulses after DNA injection. Gene transfer was improved at best by approximately 50% under certain electrical conditions (200 V for 10 ms or 1200 V for 100 micro s). Finally, multiple injections of plasmid permitted an increase in the number of transduced cells by approximately 400%.In situ injection of naked DNA into tendons is a very simple technique that permits delivery of genes with a duration of expression sufficient for clinical application aimed at modulating healing or restoration of a degenerative tendon. Despite a low transfer efficiency, this method should be compatible with clinical applications aimed at delivering therapeutic substances acting at low concentration.

Data for patients with bone metastases (BMs) of differentiated thyroid carcinoma (DTC) were retrospectively studied to identify factors associated with survival. We especially studied the impact of therapies. Among the 1977 patients followed for DTC in our department from 1958 to 1999, 109 (77 females and 32 males; age range, 20–87 yr) presented BMs. All patients except 1 underwent total thyroidectomy, followed by radioiodine therapy (≥3.7 gigabecquerels) in 95 cases. Survival rates at 5 and 10 yr were 41% and 15%, respectively. Univariate analyses indicated that a young age at BM discovery (P < 0.005) and the discovery of BM as a revealing symptom of DTC (P < 0.05) were features significantly associated with improved survival as well as radioiodine therapy (P < 10−4) and BM complete surgery (P < 0.02). Using multivariate analysis, the detection of BMs as a revealing symptom of thyroid carcinoma (P < 0.0005), the absence of metastasis appearance in other organs than bones during the follow-up (P < 0.03), the cumulative dose of radioiodine therapy (P < 0.0001), and complete BM surgery in young patients (P < 0.04) appeared as independent prognostic features associated with an improved survival.

We studied the mechanical effects of anteversion of hip prosthesis, using a geometrical model of the femoral bone derived from computed tomography sections. Linear elastic mechanical behavior was assumed for both cortical and trabecular bone. The results of finite element modeling were studied qualitatively. Stress distribution was evaluated during one-legged stance loading of models with various degrees of anteversion. The undeniable impact of anteversion raises questions about the interpretation of bone remodeling. Anteversion modifies mechanical stresses, most notably those through the femoral shaft; they are rotated around the vertical axis in the same direction as the anteversion. Changes in Von Mises stresses were larger than changes in longitudinal stresses, suggesting that anteversion may have a more significant impact on shear stresses, which may cause failure at the prosthesis-cement interface, particularly toward the middle of the femoral shaft.

The objective of this study was to conduct a radiological analysis of posture before and after lumbosacral fusion to evaluate the influence of spinal alignment on the occurrence and pattern of post surgical pain. The study included 81 patients, of whom 51 had a history of previous low back surgery. We excluded patients with suspected or confirmed nonunion. In the fusion group, the ¶27 patients who were pain free after the procedure were compared to the 54 patients with residual pain. Thirty patients had pain only or primarily when they were standing immobile, 18 when they were sitting immobile, and six in both positions. Measurements were done on full-length lateral radiographs of the spine, with the patient standing according to Duval Beaupere criteria. The subgroup with postfusion pain was characterized at baseline by a more vertical sacrum with less sacral tilt (ST) ¶(P < 0.0062) and more pelvic tilt (PT) (P < 0.0160). PT at last follow-up (PT fu) correlated with the presence of postfusion pain (NP: P = 0.0003). In the patients with postfusion pain, PT was almost twice the normal value. ST at last follow-up (ST fu) in the standing position was also correlated with the presence of postfusion pain (P < 0.0001) indicating that the sacrum remained ¶abnormally vertical in the subjects with postfusion pain. Using logistic regression, the only prognostic factor for residual pain at last follow-up was ST fu. Both at pre-operative evaluation and at last follow-up, patients with pain in the standing position or in both the standing and sitting positions were characterized at pre-operative status by a more vertical sacrum with less sacral tilt. The results of this study indicate that, achieving a strong fusion should not be the only goal. Appropriate position of the fused vertebrae is also of paramount importance to minimize muscle work during posture maintenance. The main risk is failing to correct or to causing excessive pelvic retroversion with a vertical sacrum leading to a sagittal alignment that replicates the sitting position. This situation is often accompanied by loss of lumbar lordosis and adversely affects stiff or degenerative hips.

An unusual case of vertical atlantoaxial dislocation without medulla oblongata or spinal cord injury is reported. The pathogenic process suggested occipito-axial dislocation. The case was treated surgically with excellent results on mobility and pain.

Intraoperative ultrasonography (IOUS) was used to evaluate the location and compressive effects of intraspinal fragments in thoracolumbar fractures and the efficacy of reduction maneuvers in patients operated on for isolated or attached intraspinal fragments or for global posterior wall disruption. Dynamic IOUS was used to evaluate the effects of traction and lordosis. Fifty-eight patients were evaluated using a 7.5 MHz ultrasound probe, including 27 treated by impaction, 19 by removal of apparently isolated fragments, and 12 by traction followed by lordosis for global posterior wall disruption. IOUS had limitations and problems caused by split fragments and residual pedicular attachments that can compromise intraoperative maneuvers. The risk of secondary displacement of isolated fragments treated by impaction was very high. In particular, the pinching effect produced by T-shaped fractures was commonly responsible for secondary displacement. IOUS evaluation of canal clearance after fragment removal was satisfactory, but did not provide quantitative data. IOUS was easier to perform and apparently more reliable than intraoperative myelography. The dynamic IOUS data suggest that, except for severely tilted fragments that are completely free or remain attached to a pedicle, residual discal attachments significantly influence the likelihood of successful reduction.

Corrective surgery for kyphotic deformities of the spine in ankylosing spondylitis is a major surgery for rare indications. The authors report 31 lumbar osteotomies. The goal is to correct the deformity through a posterior limited approach and to minimise the neurological risks. The modifications developed by the authors for monosegmental closing wedge osteotomies are explained. The posterior resection is rhomboid shaped with a bilateral lamina removal. An osteotomy is performed in a forwards direction on the lateral aspects of the vertebral body without bone resection. This osteoclasty allows progressive vertebral body compression. Pediclectomy is associated if the corresponding foramen at the osteotomy level becomes too narrow in the process of redressing the spine. The resection level is adjusted so that superior and inferior posterior arches come into contact with a good compression. The authors point out the risk of lateral translation. Before the osteotomy, the two adjacent vertebrae are implanted with 5-mm cylindrical pedicular screws, so that posterior fixation can be carried out at any time. Posterior monobloc fixation allows for very great compression of the osteoclasty. The authors compare the results of their experiences in opening and closing osteotomy. They progressively changed their technique for closing osteotomies, because of published vascular complications and mechanical risks (instability and pseudarthrosis in opening osteotomies). Closing osteotomy also minimises the risk of stenosis with radicular compression or traction if an important correction is performed. The level of the osteotomy varied in this series, which had a correction rate of up to 75 degrees. The choice of level depends on secondary effects on pelvic position and projection of the centre of gravity. The preferred procedure remains a monosegmental correction because it is faster and easier, with minimum bleeding. Short monobloc posterior fixation is sufficient to maintain reduction and to obtain stability from posterior compression.