Patella dislocation: an online systematic video analysis of the mechanism of injury.

BACKGROUND: The mechanism of injury (MoI) for a patellar dislocation has not been fully established. The aim of this study was to use systematic video analysis to determine the MoI of a patella dislocation. METHODS: A systematic search was conducted of three video sharing websites and three popular search engines to identify videos demonstrating a patellar dislocation. Videos were reviewed by three surgeons trained in systematic video analysis, who commented on the position of the lower limb and the situation in which the injury occurred. The results were reviewed to build a consensus of the MoI for each video. Statistical analysis was conducted for interobserver agreement (p < 0.05). RESULTS: Initial search yielded 603 videos with 13 meeting the inclusion criteria. The injuries were sustained performing a sporting activity (n = 9) or whilst dancing (n = 4). The injury was predominantly sustained during a non-contact situation (n = 10). The most common mechanism was an unbalanced individual with a flexed hip sustaining a valgus force to their flexed knee with the tibia externally rotated. CONCLUSIONS: This study provides some insight into the MoI for a patellar dislocation and the findings may assist in developing injury prevention programmes and rehabilitation protocols as well as guiding future research.

When does the patella dislocate? A systematic review of biomechanical & kinematic studies.

BACKGROUND: Patellar dislocations are a significant injury with the potential for long term problems. Little work has been done on establishing the mechanism by which this injury occurs. OBJECTIVES: To determine the mechanism of injury of a patella dislocation based on the available published literature and compare them to already proposed theories. METHODS: A systematic review of the literature was conducted following searches performed on MEDLINE, EMBASE and ProQuest from the earliest year of indexing using the following search terms in any combination: "patella", "dislocation", "mechanism of injury", "anatomy", "biomechanical" and "risk factor". A broad inclusion criteria was used that included studies that looked at patellar dislocations and instability with respect to the patellofemoral joint (PFJ) kinematics or altered kinematics of the PFJ. Studies that did not address the kinematics or biomechanics of the PFJ were excluded. Studies were appraised based on their methodology using a combination of the Critical Appraisal Skills Programme tool and the Quality Appraisal for Cadaveric Studies. RESULTS: 113 studies were identified from a search of MEDLINE, EMBASE and ProQuest databases. Following application of our inclusion criteria, a total of 23 studies were included in our review. 18 of these studies were cadaveric biomechanical studies. The remaining studies were anatomical, imaging based, and a computer simulation based study. CONCLUSIONS: These biomechanical and kinematic studies provide some evidence that a dislocation is likely to occur during early knee flexion with external rotation of the tibia and contraction of the quadriceps. There is limited evidence to support other elements of proposed mechanisms of dislocation.

Endothelial function, arterial wall mechanics and intima media thickness in juvenile idiopathic arthritis.

OBJECTIVES: Juvenile idiopathic arthritis (JIA) is a chronic inflammatory disease of children which might persist into adulthood. Systemic inflammation seen in adult RA patients has been shown to be associated with alteration in endothelial function, arterial wall mechanics and intima media thickness. Our study was planned to assess similar changes in JIA patients. METHODS: Thirty-one newly diagnosed JIA patients and a similar number of age- and sex-matched controls were enrolled in the study. Endothelial function was assessed by measuring flow mediated dilation and glyceryl trinitrate (GTN)-mediated dilation of the brachial artery. To assess arterial stiffness, various arterial wall mechanic parameters such as cross-sectional compliance, cross-sectional distensibility, shear stress and elastic modulus were derived. Intima media thickness of the common carotid artery was measured as a marker of subclinical atherosclerosis. RESULTS: The brachial artery diameter at rest was found to be slightly lower in the patients than controls (0.258 ± 0.042 vs. 0.264 ± 0.039; p=0.54). No significant difference was found in flow mediated dilation (17.71 ± 9.26 vs. 16.31 ± 8.23; p=0.53), GTN mediated dilation (25.25 ± 10.02 vs. 23.66 ± 9.79; p=0.53) or FMD: GTN mediated dilation ratio (0.730 ± 0.432 vs. 0.717 ± 0.280; p=0.89) between the cases and controls. There was also no significant difference in carotid artery intima media thickness (0.065 ± 0.0068 vs. 0.068 ± 0.007; p=0.084) between cases and controls. Cases in different subsets of JIA were also analysed separately with regards to FMD, GTN mediated dilation and cIMT but no difference was found between cases in each subset and their controls. Cross-sectional compliance was significantly lower in cases than controls (0.0016 ± 0.0005 vs. 0.002 ± 0.001; p=0.034). Cross-sectional distensibility (0.009 ± 0.003 vs. 0.011 ± 0.006; p=0.14) was also found to be lower whereas diastolic wall shear stress (299.9 ± 47.08 vs. 294.9 ± 59.5; p=0.72) and elastic modulus (1138.5 ± 1085.8 vs. 911 ± 453; p=0.19) were found to be higher in cases as compared to controls. But these differences were not statistically significant. When the subsets were analysed separately for vessel wall indices, cross-sectional compliance was found to be significantly lower in systemic arthritis patients as compared to controls. A high level of intra- and inter-observer agreement was found for all the ultrasonographically evaluated parameters. CONCLUSIONS: Arterial wall indices were found altered in JIA patients indicating increased arterial stiffness. Larger studies are required to assess endothelial dysfunction, intima media thickness and arterial stiffness in each subset of JIA patients.

Dyggve melchior clausen syndrome.

Dyggve Melchior Clausen syndrome is a rare autosomal recessive disorder, characterized by progressive spondylo epi metaphyseal dysplasia associated with mental retardation. The clinical and radiological findings resembles Morquio disease at the onset of condition, which may hinder its diagnosis. Two siblings with chatacteristic clinical (progressive postnatal dwarfism and mental retardation) and radiological features (irregular lace-like appearance of the iliac crests) are reported.

Possible serotonin syndrome associated with clomipramine after withdrawal of clozapine.

OBJECTIVE: To report on the possible development of serotonin syndrome in a patient receiving clomipramine after clozapine was withdrawn from the treatment regimen. CASE REPORT: A 44-year-old white man with a 23-year history of undifferentiated schizophrenia and obsessive-compulsive behavior had been treated with clozapine and clomipramine for several years. He tolerated both agents together well, with the exception of experiencing chronic constipation. Clomipramine was tapered and reduced to 50 mg over a period of 10 days. A worsening of ritualistic behavior was noted, and the clomipramine dosage was increased to 150 mg/d over 14 days. Simultaneously with the clomipramine dosage increase, clozapine was tapered and stopped ever a period of 19 days. The day after clozapine was stopped, while he was still receiving clomipramine 150 mg/d, he began behaving oddly, started sweating profusely, shivering, and became tremulous, agitated, and confused. He was diagnosed with possible serotonin syndrome; his symptoms resolved after clomipramine was stopped but before clozapine was restarted eight days later. DISCUSSION: There are similarities in symptoms between serotonin syndrome and clozapine withdrawal. This article discusses the reasons why this case may represent serotonin syndrome rather than clozapine withdrawal and the possible pharmacologic mechanisms involved. CONCLUSIONS: Clinicians should be aware that removing a serotonin-2a (S-HT2a) antagonist 1mm a treatment regimen including an agent that increases serotonin in the synaptic cleft may worsen clozapine withdrawal or potentially result in serious adverse drug reactions, such as serotonin syndrome.

The use of selective serotonin reuptake inhibitors for depression and psychosis complicating dementia.

This retrospective chart review examines the impact of selective serotonin reuptake inhibitors on 20 patients with both depression and psychosis complicating dementia of the Alzheimer type (DAT) and other dementias. Fifteen of the 20 patients had moderate to marked improvement in depressive and psychotic symptoms. Eleven of 12 patients with DAT had moderate to marked improvement compared to only four of eight patients with dementia from other causes. The drugs were effective in diminishing or eliminating psychotic symptoms in six patients who had previously not responded to a trial of a neuroleptic. The selective serotonin reuptake inhibitors may have an important role to play in patients with DAT who have coexisting depression and psychosis. These drugs are very well tolerated and may have a place as first-line agents in non-emergent settings where a clinician might otherwise think of instituting a neuroleptic or as a second-line agent when a neuroleptic has proven ineffective.

A randomized controlled trial of vitamin A supplementation in acute diarrhea.

Effect of vitamin A supplementation on duration of diarrhea was evaluated in 108 cases between 6 months to 5 years of age suffering from acute diarrhea of less than 3 days duration and results were compared with equal number of age and sex matched controls having comparable feeding pattern, nutritional and socio-economic status and clinical profile who did not receive vitamin A supplementation. There was no significant difference in the mean duration of diarrhea in cases who received vitamin A and the controls. However, on subgroup analysis of the study and control groups a significant (p = 0.009) beneficial effect of vitamin A supplementation was noticed in cases who had a pre-existing vitamin A deficiency with CIC stage 3/5 and above. Even though vitamin A supplementation in malnourished children did not significantly alter the duration of diarrhea, a beneficial effect was observed in children who had CIC state 3 and above in association with malnutrition (p = 0.025). Our results indicate that vitamin A supplementation does not significantly reduce the duration of a diarrheal episode. However, in children with pre-existing vitamin A deficiency particularly those who have associated malnutrition it may have a beneficial effect.

CT appearances in macronodular hepatosplenic tuberculosis: a review with five additional new cases.

Pseudotumoral or macronodular hepatosplenic tuberculosis (HSTB) is rare. Only 31 cases have been documented in imaging literature so far. Presented is the clinico-imaging review with five additional new cases of this uncommon variety. Due to nonspecific wide spectrum of imaging appearances, biopsy is mandatory in almost all cases. Clinical recovery and resolution of lesions on imaging may not be directly proportional.

Serotonin-depleting midbrain lesions fail to mitigate hyperphagia and obesity in the Zucker fatty rat.

Previous research has shown that damage to the dorsal and median raphe nuclei of rats can impede the subsequent development of hypothalamic hyperphagia and obesity as well as impair the defense of established hypothalamic obesity in response to food deprivation. The present study sought to determine if raphe injury might alter the development of another form of obesity, namely that which occurs spontaneously in the Zucker fatty rat. Subjects were 20 obese females (fafa; mean weight of 200 g) and 20 lean littermate controls (FaFa females; mean weight of 150 g). Following 10 days of baseline intake and weight recordings, half of each group received radio-frequency heat lesions of the dorsal and median raphe nuclei while the other half received sham surgery. Except for a mild suppression of food intake and weight gain during the first few days after lesioning, raphe injury did not alter the hyperphagia or obesity shown by fatties over the 7 week ad lib feeding period studied. Additional 24-hr intake tests of varying sucrose and quinine solutions revealed reduced sucrose acceptance and enhanced quinine rejection by fatties much as has been seen in previous studies of hypothalamic obese rats. Terminal assays of forebrain monoamine levels confirmed that raphe lesions were effective in depleting serotonin (-71% compared to controls) without producing major changes in norepinephrine or dopamine (-14% and +2%, respectively). The inability of raphe lesions to mitigate this form of hyperphagia and obesity suggests that earlier observations of their attenuating effects on hypothalamic obesity were not due to non-specific impairments of behavioral or metabolic factors necessary to permit overeating and weight gain.