A small molecule ligand for the novel pain target, GPR171, produces minimal reward in mice.

ProSAAS is one of the most abundant proteins in the brain and is processed into several smaller peptides. One of which, BigLEN, is an endogenous ligand for the G protein-coupled receptor, GPR171. Recent work in rodent models has shown that a small-molecule ligand for GPR171, MS15203, increases morphine antinociception and is effective in lessening chronic pain. While these studies provide evidence for GPR171 as a possible pain target, its abuse liability has not yet been assessed and was evaluated in the current study. We first mapped the distribution of GPR171 and ProSAAS throughout the reward circuit of the brain using immunohistochemistry and showed that GPR171 and ProSAAS are localized in the hippocampus, basolateral amygdala, nucleus accumbens, prefrontal cortex. In the major dopaminergic structure, the ventral tegmental area (VTA), GPR171 appeared to be primarily localized in dopamine neurons while ProSAAS is outside of dopamine neurons. Next, MS15203 was administered to mice with or without morphine, and VTA slices were stained for the immediate early gene c-Fos as a marker of neuronal activation. Quantification of c-Fos-positive cells revealed no statistical difference between MS15203 and saline, suggesting that MS15203 does not increase VTA activation and dopamine release. The results of a conditioned place preference experiment showed that treatment with MS15203 produced no place preference indicating a lack of reward-related behavior. Taken together this data provides evidence that the novel pain therapeutic, MS15203, has minimal reward liability. Therefore, GPR171 deserves further exploration as a pain target. SIGNIFICANCE STATEMENT: MS15203, a drug that activates the receptor GPR171, was previously shown to increase morphine analgesia. The authors use in vivo and histological techniques to show that it fails to activate the rodent reward circuitry, providing support for the continued exploration of MS15203 as a novel pain drug, and GPR171 a novel pain target.

Instantaneous 4D micro-particle image velocimetry (µPIV) via multifocal microscopy (MUM).

Multifocal microscopy (MUM), a technique to capture multiple fields of view (FOVs) from distinct axial planes simultaneously and on one camera, was used to perform micro-particle image velocimetry (µPIV) to reconstruct velocity and shear stress fields imposed by a liquid flowing around a cell. A diffraction based multifocal relay was used to capture images from three different planes with 630 nm axial spacing from which the axial positions of the flow-tracing particles were calculated using the image sharpness metric. It was shown that MUM can achieve an accuracy on the calculated velocity of around (0.52 ± 0.19) µm/s. Using fixed cells, MUM imaged the flow perturbations at sub-cellular level, which showed characteristics similar to those observed in the literature. Using live cells as an exemplar, MUM observed the effect of changing cell morphology on the local flow during perfusion. Compared to standard confocal laser scanning microscope, MUM offers a clear advantage in acquisition speed for µPIV (over 300 times faster). This is an important characteristic for rapidly evolving biological systems where there is the necessity to monitor in real time entire volumes to correlate the sample responses to the external forces.

Phase-contrast 3D tomography of HeLa cells grown in PLLA polymer electrospun scaffolds using synchrotron X-rays.

Advanced imaging is useful for understanding the three-dimensional (3D) growth of cells. X-ray tomography serves as a powerful noninvasive, nondestructive technique that can fulfill these purposes by providing information about cell growth within 3D platforms. There are a limited number of studies taking advantage of synchrotron X-rays, which provides a large field of view and suitable resolution to image cells within specific biomaterials. In this study, X-ray synchrotron radiation microtomography at Diamond Light Source and advanced image processing were used to investigate cellular infiltration of HeLa cells within poly L-lactide (PLLA) scaffolds. This study demonstrates that synchrotron X-rays using phase contrast is a useful method to understand the 3D growth of cells in PLLA electrospun scaffolds. Two different fiber diameter (2 and 4 µm) scaffolds with different pore sizes, grown over 2, 5 and 8 days in vitro, were examined for infiltration and cell connectivity. After performing visualization by segmentation of the cells from the fibers, the results clearly show deeper cell growth and higher cellular interconnectivity in the 4 µm fiber diameter scaffold. This indicates the potential for using such 3D technology to study cell-scaffold interactions for future medical use.

Visualising the 3D microstructure of stained and native intervertebral discs using X-ray microtomography.

Intervertebral disc degeneration (IVDD) is linked to low back pain. Microstructural changes during degeneration have previously been imaged using 2D sectioning techniques and 3D methods which are limited to small specimens and prone to inducing artefacts from sample preparation. This study explores micro computed X-ray tomography (microCT) methods with the aim of resolving IVD 3D microstructure whilst minimising sample preparation artefacts. Low X-ray absorption contrast in non-mineralised tissue can be enhanced using staining and phase contrast techniques. A step-wise approach, including comparing three stains, was used to develop microCT for bovine tail IVD using laboratory and synchrotron sources. Staining successfully contrasted collagenous structures; however not all regions were stained and the procedure induced macroscopic structural changes. Phase contrast microCT of chemically fixed yet unstained samples resolved the nucleus pulposus, annulus fibrosus and constituent lamellae, and finer structures including collagen bundles and cross-bridges. Using the same imaging methods native tissue scans were of slightly lower contrast but free from sample processing artefacts. In the future these methods may be used to characterise structural remodelling in soft (non-calcified) tissues and to conduct in situ studies of native loaded tissues and constructs to characterise their 3D mechanical properties.

Posterolateral fusion versus Dynesys dynamic stabilization: Retrospective study at a minimum 5.5years' follow-up.

INTRODUCTION: Lumbar fusion is one of the most widespread techniques to treat degenerative lumbar pathology. To prevent complications such as non-union or adjacent segment degeneration, dynamic stabilization techniques were developed, but with controversial results. The aim of the present study was to compare long-term radiologic and clinical results between fusion and dynamic stabilization. MATERIAL AND METHODS: A single-center retrospective study included patients with recurrent lumbar discal hernia or lumbar canal stenosis managed by posterolateral fusion or by dynamic stabilization associated to neurologic release. Patients were seen in follow-up for radiological and clinical assessment: visual analog pain scale (VAS), Oswestry Disability Index (ODI), Short Form-12 (SF-12), adjacent segment disease (ASD), and intervertebral range of motion (ROM). RESULTS: Fifty-eight patients were included: 25 in the fusion group (FG), and 33 in the Dynesys® group (DG). VAS scores were significantly lower in DG than FG. ODI was 14.6±2.8 in DG, versus 19.4±3.3 in FG (P=0.0001). SF-12 physical subscore was significantly higher in DG. ROM was 4.1±2° in DG, vs. 0.7±0.5° in FG (P=0.001). Radiologic ASD was significantly greater in FG than DG (36% vs. 12.1%; P=0.012), without difference in clinical expression (DG, 1 case; FG, 2 cases). CONCLUSION: Dynamic stabilization provided clinical and radiological results comparable to those of posterolateral fusion in these indications (although level L5-S1 was not studied). LEVEL OF EVIDENCE: IV.

Endochondral Growth Defect and Deployment of Transient Chondrocyte Behaviors Underlie Osteoarthritis Onset in a Natural Murine Model.

OBJECTIVE: To explore whether aberrant transient chondrocyte behaviors occur in the joints of STR/Ort mice (which spontaneously develop osteoarthritis [OA]) and whether they are attributable to an endochondral growth defect. METHODS: Knee joints from STR/Ort mice with advanced OA and age-matched CBA (control) mice were examined by Affymetrix microarray profiling, multiplex polymerase chain reaction (PCR) analysis, and immunohistochemical labeling of endochondral markers, including sclerostin and MEPE. The endochondral phenotype of STR/Ort mice was analyzed by histologic examination, micro-computed tomography, and ex vivo organ culture. A novel protocol for quantifying bony bridges across the murine epiphysis (growth plate fusion) using synchrotron x-ray computed microtomography was developed and applied. RESULTS: Meta-analysis of transcription profiles showed significant elevation in functions linked with endochondral ossification in STR/Ort mice (compared to CBA mice; P < 0.05). Consistent with this, immunolabeling revealed increased matrix metalloproteinase 13 (MMP-13) and type X collagen expression in STR/Ort mouse joints, and multiplex quantitative reverse transcriptase-PCR showed differential expression of known mineralization regulators, suggesting an inherent chondrocyte defect. Support for the notion of an endochondral defect included accelerated growth, increased zone of growth plate proliferative chondrocytes (P < 0.05), and widespread type X collagen/MMP-13 labeling beyond the expected hypertrophic zone distribution. OA development involved concomitant focal suppression of sclerostin/MEPE in STR/Ort mice. Our novel synchrotron radiation microtomography method showed increased numbers (P < 0.001) and mean areal growth plate bridge densities (P < 0.01) in young and aged STR/Ort mice compared to age-matched CBA mice. CONCLUSION: Taken together, our data support the notion of an inherent endochondral defect that is linked to growth dynamics and subject to regulation by the MEPE/sclerostin axis and may represent an underlying mechanism of pathologic ossification in OA.

Macrophage migration inhibitory factor promotes eosinophil accumulation and tissue remodeling in eosinophilic esophagitis.

Macrophage migration inhibitory factor (MIF) is involved in eosinophil biology and in type 2 inflammation, contributing to allergic and helminthic diseases. We hypothesized that MIF participates in the pathogenesis of eosinophilic esophagitis (EoE), an allergic condition characterized by esophageal eosinophilic inflammation. MIF is highly expressed in esophageal mucosa of patients with EoE, compared with gastro-esophageal reflux disease and control patients, where it co-localizes predominantly with eosinophils. In vitro, recombinant MIF promotes human eosinophil chemotaxis, while MIF antagonist and CXCR4 antagonist, AMD3100, revert this effect. In a model of EoE induced by ovalbumin, Mif-deficient mice have reduced inflammation and collagen deposition compared with wild-type (WT) mice. Importantly, treatment of WT mice with anti-MIF or with AMD3100 during the challenge phase prevents accumulation of eosinophils and tissue remodeling. Conversely, recombinant MIF promoted tissue eosinophil inflammation in allergic mice. Together, these results implicate MIF in the pathogenesis of esophageal inflammation and suggest that targeting MIF might represent a novel therapy for EoE.

Post-traumatic lower cervical spine instability: arthrodesis clinical and radiological outcomes at 5 years.

BACKGROUND: Anterior cervical fusion is widely used to treat spinal injuries. Radiological evidence of disc abnormalities may develop on either side of the fused segment, raising concern about the potential for inducing adjacent-segment disease. Here, we report the long-term clinical, functional, and radiological outcomes after anterior cervical fusion. HYPOTHESIS: Anterior cervical fusion influences the development of adjacent-segment disease. MATERIALS AND METHODS: In a retrospective study, 15 patients aged 17 to 50 years were re-evaluated more than 5 years after anterior spinal fusion to treat post-traumatic cervical-spine instability. We used the Neck Disability Index (NDI) to assess function. Static and dynamic radiographs of the cervical spine were obtained. RESULTS: NDI values indicated good clinical and functional outcomes, and fusion was achieved consistently. Adjacent-segment disease was a consistent finding at last follow-up but induced no neurological manifestations. Complete fusion of a level adjacent to the treated level was noted in 2 patients. Revision surgery for adjacent-segment disease was not required in any patient. CONCLUSION: The causative factors of adjacent-segment disease are controversial. Disc degeneration is a normal manifestation of the ageing process. Nevertheless, disc disease is more prevalent at levels adjacent to interbody fusion than in the normal population, suggesting accelerated disc degeneration due to increased loading of the adjacent levels. Furthermore, lesions that are missed during the pre-operative work-up may play a role, as the available investigations do not always have high negative predictive values. LEVEL OF EVIDENCE: Level IV, retrospective study.

Arthrodesis in septic knees using a long intramedullary nail: 17 consecutive cases.

BACKGROUND: Intramedullary nailing using long or modular nails is the most reliable mean of achieving femorotibial fusion. Here, we report the operative, clinical, functional, and radiological outcomes of 17 long intramedullary nail arthodeses in patients with infection. HYPOTHESIS: Clinical and functional outcomes after long intramedullary nailing are at least as good as those obtained using other implants. MATERIALS AND METHODS: We retrospectively reevaluated 17 patients after unilateral two-stage knee arthrodesis with a long titanium intramedullary nail and autologous bone grafting. We evaluated satisfaction, leg length discrepancy, and function (Lequesne and WOMAC indices). Radiographs were obtained to assess fusion, time to fusion, and femorotibial angles. RESULTS: No cases of material failure were recorded. One or more complications occurred in seven patients. Mean limb shortening was 27.6mm. Of the 17 patients, 15 were satisfied with the procedure. The mean Lequesne index was 10.5/24 and the mean overall WOMAC score was 26/88. Fusion was achieved in 16 patients, with a mean time to fusion of 5 months. Mean femorotibial angles were 178.6° of varus and 1.9° of flexion. DISCUSSION: This simple and rapid surgical technique provides functional outcomes similar to those obtained using modular nails. The fusion rate is high. Nail extraction is simple and causes minimal damage, in contrast to modular nails. Increased attention to misalignment is needed. LEVEL OF EVIDENCE: Level IV, retrospective study.

Computation of full-field displacements in a scaffold implant using digital volume correlation and finite element analysis.

Measurements of three-dimensional displacements in a scaffold implant under uniaxial compression have been obtained by two digital volume correlation (DVC) methods, and compared with those obtained from micro-finite element models. The DVC methods were based on two approaches, a local approach which registers independent small volumes and yields discontinuous displacement fields; and a global approach where the registration is performed on the whole volume of interest, leading to continuous displacement fields. A customised mini-compression device was used to perform in situ step-wise compression of the scaffold within a micro-computed tomography (µCT) chamber, and the data were collected at steps of interest. Displacement uncertainties, ranging from 0.006 to 0.02 voxel (i.e. 0.12-0.4 µm), with a strain uncertainty between 60 and 600 µÎµ, were obtained with a spatial resolution of 32 voxels using both approaches, although the global approach has lower systematic errors. Reduced displacement and strain uncertainties may be obtained using the global approach by increasing the element size; and using the local approach by increasing the number of intermediary sub-volumes. Good agreements between the results from the DVC measurements and the FE simulations were obtained in the primary loading direction as well as in the lateral directions. This study demonstrates that volumetric strain measurements can be obtained successfully using DVC, which may be a useful tool to investigate mechanical behaviour of porous implants.

Odontoid fractures anterior screw fixation: a continuous series of 36 cases.

INTRODUCTION: Fracture of the odontoid process represents 5 to 15% of cervical spine fractures. Anterior screw fixation is the reference technique in unstable posterior oblique or horizontal odontoid fracture. OBJECTIVE: We describe results with an original anterior screw fixation technique using a curved thoraco-lumbar pedicle awl to facilitate intra-operative reduction. PATIENTS AND METHODS: This is a retrospective study of 36 consecutive patients who underwent anterior screw fixation for odontoid process fracture. Mean age was 70.3 years. Twenty six patients had type II and 10 type III fracture on the Anderson-D'Alonzo classification. On the Roy-Camille classification, there were 34 posterior oblique fractures and two horizontal fractures. There were no anterior oblique fractures. Bony union was assessed on CT-scan at 3 months. We describe the surgical technique, which used a 4.5mm cannulated cancellous lag screw in all cases. RESULTS: Mean follow-up was 3 years (range, 4 months to 8 years). No intra-operative complications were observed. Union rate was 95% and the average time to union was 5 months (3 to 6 months). DISCUSSION: Anterior screw fixation is a common surgical treatment for posterior oblique and horizontal odontoid process fractures. We detail a reliable and reproducible intra-operative reduction maneuver to obtain a good union rate without complications. LEVEL OF EVIDENCE: Level IV. Retrospective therapeutic study.

Video-assisted treatment of thoracolumbar junction fractures using a specific distractor for reduction: prospective study of 50 cases.

Posterior instrumentation allows good osteosynthesis for thoracolumbar junction fractures. However, in approximately 20% of cases, anterior bone defects may persist, leading to pseudoarthrosis and loss of reduction. Anterior approaches can circumvent this drawback, but they are considered aggressive with a high rate of complications. The advent of the endoscopic mini-invasive techniques has led to a reduction in the number of complications while maintaining the same consolidation rate. Nevertheless, poor restitution of anatomic curves is a reproach for this technique. This prospective study reports clinical and radiological result of 50 patients (19 women and 31 men) operated between April 2000 and March 2006 with a video-assisted anterior approach using an endodistractor for reduction and consequent insertion of the implant. There were A3 (n = 44), A2 (n = 2), A1 (n = 3) and C1 (n = 1) fractures (Magerl classification). The specific system for fracture reduction was used in the last 39 cases of this series. A Pyramesh cage (Medtronic, Memphis, USA) was used in 15 patients, a peek cage (Creaspine, Bordeaux, France) in 30 patients and a tricortical graft in 5 patients. Standard X-rays and CT scan were performed pre-operatively. Kyphosis, and angulations were measured pre-, per- and post-operatively. Mean immediate postoperative gain in localized kyphosis was 12.18 degrees and mean gain at last follow-up was 11.71 degrees. Mean immediate postoperative gain in RA was 13.24 degrees and remained identical at last follow-up. Five patients had a transient pulmonary atelectasia and there was one pulmonary infection. No neurological complication occurred. Fracture reduction is comparable to the best thoracotomy series while limiting approach-related complications.

The Valenti technique in the treatment of hallux rigidus.

INTRODUCTION: Metatarsophalangeal joint osteoarthritis of the great toe (hallux rigidus) is a frequent condition for which numerous surgical techniques have been proposed. The most used ones are cheilectomy and arthrodesis. The objectives of this retrospective study are to present the midterm results of the Valenti procedure and to compare these results with those from other recognized surgical techniques. MATERIALS AND METHODS: We conducted a retrospective analysis of a continuous group of 32 patients (41 cases) presenting hallux rigidus and treated using the Valenti technique from November 1999 to July 2004. The mean age of these patients at the time of surgery was 57 years. Forty-one percent of these patients also presented a static disorder of the foot. One or several additional procedures were undertaken, at the time of surgery, in 24% of these cases. Patients were assessed using the AOFAS score completed by the walking distance test, the gait test, the tiptoe test and self-evaluation of patient satisfaction. The radiographic work-up before surgery and at follow-up showed the progression of the joint space changes and allowed us to evaluate plantar subluxation at the base of the first phalanx under the metatarsal head. RESULTS: Twenty-four patients (32 cases) were reviewed and evaluated with a mean follow-up of 5.5 years. Two cases of reflex sympathetic dystrophy were observed as complications. The mean final score was 81 out of 100 from a preoperative score of 47 out of 100. Pain was absent or only occasional in 94% of the cases. Discomfort wearing shoes was absent or moderate in 91% of the cases. Joint range of movement was greater than 30 degrees in 72% of the cases and the toes were stable. Walking distance was unlimited in 79% of the cases. A mean 30% plantar subluxation at the base of the first phalanx was noted at follow-up, with no clinical consequence. The results were comparable irrelevantly of the hallux rigidus grade being treated. DISCUSSION: The numerous techniques proposed achieve comparable results both in terms of pain relief and functional result but each one has its own limitations. Only arthroplasties with silastic implants and the Keller technique give less satisfactory results. Arthrodesis remains the first-choice treatment for advanced hallux rigidus but failure is possible in case of technical error or malunion. Cheilectomy, a conservative intervention, is ideal for lesions that are not too advanced or remain limited to the dorsal part of the joint; this conservative option presents generally no specific complications. Prosthetic replacement--with, to date, little long-term experience for total arthroplasty--remains controversial because the results deteriorate over time. The Valenti procedure exposes the patient to a possible risk of metatarsophalangeal joint destabilization if the resection is too great, but this does not impair the final functional outcome. CONCLUSION: The arthrectomy described by Valenti is a highly reproducible intervention. We find it to be a good compromise between mobility and stability, providing good results for all hallux rigidus grades and entailing a low complication rate. LEVEL OF CLINICAL EVIDENCE: Level IV. Therapeutic Study.

[Anatomic variations of the ilio-caval junction encountered in disk prosthesis implantation]. / Incidence de la situation anatomique de la bifurcation ilio-cave lors de la mise en place d'une prothèse discale.

PURPOSE OF THE STUDY: The retroperitoneal mini-invasive anterior approach to the lumbar spine is widely used for disc excision and insertion of a prosthetic disc. A large operating window is needed. Venous wounds constitute one of the most serious complications. We analyzed the angle and position of the iliocaval on the preoperative angio-MRI in search for correlations with the intraoperative findings. Our aim was to determine whether the preoperative angio-MRI gives indications concerning the operative difficulty and the best strategy for prosthesis fitting. MATERIAL AND METHOD: This prospective study included 35 consecutive patients who underwent surgery for implantation of a Maverick disc prosthesis. Average patient age was 46.7 years. The indication for surgery was isolated degenerative discopathy with invalidating chronic low back pain without alteration of the muscle masse or facet joints. A preoperative angio-MRI was performed with T1 spin-echo sequences for the coronal slices and T2 axial slices passing through the upper extremity of the L5-S1 disc. We searched for correlations between the MRI and operative findings. Elements studied were those used in the Capellades classification: height of the iliocaval junction (high, very high, low, very low), position of the common iliac vein (lateral, intermediate, medial), angle formed by the two common iliac veins. RESULTS: The lateral position was the most frequent (31.5%). The average junction angle was 65 degrees). The only position where it was not possible to "pass" under the iliocaval junction was for a very low medial localization with a narrow angle (45 degrees). DISCUSSION: Our series included a homogenous group comparable with other series in the literature. The junction angle for very low medial localizations is of considerable importance because it is impossible to fit the implant in the L5-S1 under the iliocaval junction if the angle is over 60 degrees. CONCLUSION: The position of the iliocaval junction, and particularly its angle, are of considerable importance for insertion of an L5-S1 disc prosthesis. The preoperative angio-MRI provides information on the potential difficulty of the insertion. In addition, with this preoperative information, the patient can be warned that it may not be possible to insert the implant so that a therapeutic alternative may be proposed.

[High tibial open-wedge osteotomy using a tricalcium phosphate substitute: 70 cases with 18 months mean follow-up]. / Valgisation tibiale par ouverture médiale utilisant un coin de céramique de phosphate tricalcique: á propos de 70 cas revus avec un recul moyen de 18 mois.

PURPOSE OF THE STUDY: We report our experience with a B tricalcium phosphate ceramic to fill open-wedge tibial osteotomy gaps. MATERIAL AND METHODS: Seventy high tibial open-wedge osteotomies were performed in 70 patients (47 men and 23 women). Ostotomy was performed for osteoarthritis in 56 knees, Ahlback classification stage I (n = 18), stage II (n = 32), stage III (n = 6) and for congenital varus in 14. Mean patient age was 45.2 years (16-69). We used a wedge-shaped piece of ceramic with an appropriate angle, which was associated with granulated material to complete the gap filling for the last 20 cases. One or two staples were used for fixation. Clinical and radiological outcome was assessed at 6 weeks, 3 months, 6 months, and at last follow-up. Mean follow-up was 18 months. RESULTS: There were no biological or clinical complications related to biomaterial intolerance. Tolerance to the osteosynthesis material was mediocre since we observed one infection and 12 cases of pain related to the staples which required material removal in 8 patients. Bone healing was achieved in 98.5%. Final correction was between 3 degrees and 6 degrees valgus in 80.5%. There was a loss of correction angle between the postoperative film and the bone healing film. Factors related to sustained correction were: non-fractured wedge, intact lateral tibial cortical, osteosynthesis with two staples. Osteointegration was good and rapid in 96%. We found two complete lucent lines at last follow-up but with variable resorption depending on the shape of the bone substitute. CONCLUSION: Use of a ceramic wedge to fill high tibial medial open-wedge osteotomy gap is a reliable reproducible technique providing correction without formation of a malalignment callus. Bone healing is achieved in 98.5% of the cases at about three months. Osteointegration is good in 96%. Resorption is complete and rapid when the substitute is implanted in granular form in a cancellous zone and is partial and slow when implanted as a massive wedge.

[Video-assisted mini-thoracotomy for surgical treatment of thoracolumbar junction fractures]. / Traitement des fractures de la charnière thoraco-lombaire par thoracotomie mini-invasive vidéo assistée: a propos de 20 cas.

PURPOSE OF THE STUDY: There are several solutions for the treatment of fractures of the thoracolumbar junction (classical anterior, posterior, combined approaches). The advent of video-assisted minimally invasive techniques has helped minimize complications. The aim of this work was to analyze the clinical and radiological outcome in a prospective series of 20 patients who underwent video-assisted mini-thoracotomy for the treatment of thoracolumbar junction fractures. MATERIAL AND METHODS: This prospective study included 20 patients, mean age 43.3 years, with at least one year follow-up. All patients presented a normal neurological examination (Frankel E). Fractures were classified Magerl A (n = 19) and B (n = 1). Corporectomy/correction (aided with an endodistractor in the last nine cases) was performed with grafting and osteosynthesis. Perioperative and postoperative complications were noted. Focal kyphosis and regional angulation were noted before and after the operation and at last follow-up using the Stagnara system. RESULTS: The arthrodesis had fused at last follow-up in all patients. There were three cases of alelectasia which regressed in two months. Overall outcome showed satisfactory angular correction which was maintained at last follow-up. The gain in focal kyphosis was 13.71 degrees on average in the immediate postoperative period and persisted at last follow-up (13.31degrees). The gain in corrected regional angulation was 14 degrees in the immediate postoperative period and 14 degrees at last follow-up. The gain in focal kyphosis and regional angulation was two-fold greater with the endodistractor than with external maneuvers. DISCUSSION: The complication rate was very low. Corrections obtained were comparable with those reported in the literature and persisted over time. CONCLUSION: Bearing in mind the learning curve, there are fewer complications with the video-assisted minimally invasive approach than with classical thoracotomy or anterior surgery. This is true for perioperative and early and late postoperative complications. The correction achieved is satisfactory and lasting. A specific ancillary is essential for the reduction and for fitting the anterior graft without lost of correction. This technique combines the best results achieved with thoracotomy (Onimus) with a limited rate of complications.

[Pertrochanteric fractures: a randomized prospective study comparing dynamic screw plate and intramedullary fixation]. / Comparaison vis-plaque dynamique et ostéosynthèse intra-médullaire antérograde dans les fractures pertrochantériennes: une étude prospective randomisée.

PURPOSE OF THE STUDY: The objective of this study was to compare the dynamic hip screw (Synthes) and intramedullary fixation (Targon PF, Aesculap) for the treatment of pertrochanteric fractures in terms of stability, complications and cost effectiveness. MATERIAL AND METHODS: This prospective randomized study included 60 patients hospitalized in an emergency setting for pertrochanteric fractures between December 2003 and June 2004. All surgeons in our unit participated in the study. Two fixation systems were used: the Targon proximal femoral nail (Aesculap) and the screw-plate dynamic hip screw (Synthes). We noted: patient status (ASA classification), operative data (type of implant, duration), postoperative data (blood loss, radiographic findings, early complications), and outcome (Harris score, time to walking, mortality). All patients were assessed three months after surgery. The series included 60 patients, 14 men (23%) and 46 women (77%). The Targon PF nail was used for 34 patients and the DHS for 26. In the intramedullary fixation group mean age was 81 years (SD = 12.8, range 23-96); it was 82 years (SD 9.8, range 47-97) in the screw-plate group. The AO classification was: intramedullary fixation 31A1 (n = 11), 31A2 (n = 20), 31A3 (n = 3); screw-plate 31A1 (n = 14), 31A2 (n = 11), 31A3 (n = 1). Thirty-one fractures were stable, 29 unstable. Unstable fractures were treated with the Targon PF nail (n = 18) and the DHS screw-plate (n = 11). Stable fractures were treated with the Targon PF nail (n = 15) and the DHS screw-plate (n = 15). RESULTS: Mean operative time was 35 minutes for intramedullary nailing and 42 mintues for screw-plate fixation. Mean blood loss was 410 ml for intramedullary nailing and 325 ml for screw-plate fixation (p = 0.07). Mean hospital stay was the same (11 days) in both groups. At three months, mechanical complications involved migration of the cervical screw outside the femoral head for three Targon PF fixations and for two DHS fixations. Screw migration was favored by fracture instability and presence of osteoporosis. There were two deaths in the intramedullary nailing group and one in the screw-plate group. Time to walking was 20 days on average in the intramedullary nailing group and 25 days in the screw-plate group. The mean Harris hip score was 60 in the intramedullary group and 59 in the screw-plate group. DISCUSSION AND CONCLUSION: Data in the literature report an advantage for intramedullary nailing, particularly a mechanical advantage, for the treatment of pertrochanteric fractures. Our findings show that good results are obtained with the screw-plate fixation using the DHS with less blood loss and at a lower cost.

[Pulmonary involvement in children with AIDS: clinical study and necropsy of 14 cases]. / Acometimento pulmonar em crianças com a síndrome da imunodeficiência humana (AIDS): estudo clínico e de necrópsia de 14 casos.

BACKGROUND: To describe clinical, laboratorial, radiological, and histopathological lung findings from necroscopy of aidetic children with pulmonary disease. MATERIAL AND METHODS: Fourteen children admitted at the Hospital Universitário Antônio Pedro - Universidade Federal Fluminense, Niterói, RJ, and Instituto de Puericultura e Pediatria Martagão Gesteira - Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, between 1989 and 1996, were revised in a retrospective survey. RESULTS: Eight were males (57%). The median age was 1.2 years old (from three months to nine years). Nine children (64.4%) were younger than 24 months old. The HIV transmission was vertical in 10 (71%) children. In these cases, five mothers were contaminated from heterosexual relations. Pneumonia (n=8), oral candidiasis (n=8), and diarrhea (n=5) were the most common previous conditions. The most frequent signs and symptoms on admission were fever (n=12), respiratory distress (n=10), cough (n=10), peripheral lymphadenopathy (n=11), hepatomegaly and/or splenomegaly (n=10), and malnutrition (n=9). The chest x-rays findings were condensation (n=5) and diffuse infiltrates (n=6) patterns. The microscopic lung characteristics were compatibles with pneumonia by cytomegalovirus (CMV) (n=9), bacteria (n=8), Pneumocystis carinii (n=3), Toxoplasma gondii (n=1), Hystoplasma capsulatum (n=1) and Lymphocytic interstitial pneumonia (n=1). The association between CMV and bacteria was observed in six cases. CONCLUSIONS: Age less than two years old, vertical transmission, inespecific clinical presentation of pneumonia, and infiltrates and condensation patterns at the x-rays were the predominant characteristics. Cytomegalovirus and bacteria were the most common etiologic agents, being their association frequent. Lymphocytic interstitial pneumonia and pneumonia by P. carinii were not common causes of pulmonary disease.

Acometimento pulmonar em crianças com a síndrome da imunodeficiência humana (AIDS): estudo clínico e de necrópsia de 14 casos / Necroscopic study of 14 children with AIDS and pneumonia

OBJETIVOS: Descrever os aspectos clínicos, laboratoriais, radiológicos e anatomopatológicos encontrados em tecidos pulmonares de necrópsias de crianças com Aids e acometimento pulmonar. MÉTODOS: Foram revisados, retrospectivamente, prontuários, radiografias simples de tórax e laudos de necrópsias de 14 crianças com Aids e acometimento pulmonar. RESULTADOS: Oito casos eram do sexo masculino e seis do feminino. As idades variaram de três meses a nove anos, mediana de 1,2, sendo nove deles menores de dois anos. A transmissäo foi vertical em 10 pacientes, dos quais cinco mäes tinham história de contaminaçäo por relaçäo heterossexual; três, por hemotransfusäo e em duas, ignorada. Pneumonia (n=8), candidíase oral (n=8) e diarréia (n=5) foram as doenças prévias mais referidas. Os sinais e sintomas observados à internaçäo foram febre (n=12), dispnéia (n=10), tosse (n=11), linfoadenomegalia (n=11), hepato e/ou esplenomegalia (n=10), desnutriçäo (n=9), palidez (n=8), cianose (n=5) e baqueteamento digital (n=2). Os achados radiológicos mais comuns foram infiltrados difusos (n=6) e condensaçöes (n=5). As alteraçöes histológicas pulmonares foram compatíveis com pneumonia pelo citomegalovírus (n=9), por bactérias (n=8), por Pneumocystis carinii (n=3), por Hystoplasma capsulatum (n=1), por Toxoplasma gondii (n=1) e pneumonia intersticial linfocítica (n=1). A associaçäo CMV e bactéria foi observada em seis casos. CONCLUSÖES: Houve predomínio de menores de dois anos, de transmissäo vertical, de quadro clínico inespecífico de doença pulmonar e de infiltrados e condensaçöes à radiografia. Citomegalovírus e bactérias foram os agentes mais comuns, sendo freqüente a sua associaçäo. Pneumonia Intersticial Linfocítica e Pneumonia pelo P. carinii näo foram causas freqüentes de doenças pulmonares