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The joint forces and moments are commonly used in gait analysis. They can be computed by four different 3D inverse dynamic methods proposed in the literature, either based on vectors and Euler angles, wrenches and quaternions, homogeneous matrices, or generalized coordinates and forces. In order to analyze the influence of the inverse dynamic method, the joint forces and moments were computed during gait on nine healthy subjects. A ratio was computed between the relative dispersions (due to the method) and the absolute amplitudes of the gait curves. The influence of the inverse dynamic method was negligible at the ankle (2%) but major at the knee and the hip joints (40%). This influence seems to be due to the dynamic computation rather than the kinematic computation. Compared to the influence of the joint center location, the body segment inertial parameter estimation, and more, the influence of the inverse dynamic method is at least of equivalent importance. This point should be confirmed with other subjects, possibly pathologic, and other movements.

This article summarises the presentations at the Sports Medicine and Rehabilitation Study Day held by the Haywood Club at The Medical Society of London on 21 September 2006. The event was attended by over 100 serving and retired DMS personnel and included talks on a diverse range of subjects from the newly established speciality of Sports and Exercise medicine, the role of physiotherapy, exercise therapy and podiatry, core stability, tendon disorders, anterior knee pain, and the management of chronic pain.

Using optical spectroscopy with a derivative technique, we find for the high Tc cuprate Bi2Sr2CaCu2O8+delta (Bi-2212) evidence for a new high energy scale at 900 meV beyond the two previously well-known ones at roughly 50 and 400 meV. The intermediate scale at 400 meV has recently been seen in angle-resolved photoemission spectroscopy experiments along the nodal direction as a large kink. In YBa2Cu3O6.50, the three energy scales are shifted to lower energy relative to Bi-2212 and we observe the emergence of a possible new high energy feature at 600 meV.

Objective: To present a case of a true fusiform basilar artery aneurysm that underwent spontaneous thrombosis after placement of two overlapping Neuroform stents (Boston Scientific/Target, Fremont, CA)., Clinical Presentation: A 45-year-old woman with transient syncopal episodes experienced a fall and presented to the emergency room. Incidentally, a non-contrast head computed tomographic scan and digital subtraction angiography demonstrated an unruptured, fusiform mid-basilar artery aneurysm., Intervention: Endovascular treatment was initiated by using a stent-assisted coil embolization technique with placement of a self-expanding, dedicated intracranial, Neuroform stent in the basilar artery across the aneurysm's fusiform neck. Attempts to access the aneurysm for coil embolization resulted in transient migration of the stent into the aneurysm sac. A second Neuroform stent was advanced in telescoping fashion for salvage and stable coverage across the entire aneurysm; therefore, coil embolization was deferred to allow stent endothelialization. After 6 weeks on dual antiplatelet therapy, the patient presented with transient ischemic symptoms suggesting top of the basilar artery syndrome. Subsequent magnetic resonance imaging scans and angiography indicated circumferential thrombus formation in the aneurysm sac but patent flow in the basilar artery. A computed tomographic scan at 6 months and digital subtraction angiography at 12 months confirmed complete thrombosis of the fusiform mid-basilar artery aneurysm with basilar artery reconstruction., Conclusion: Overlapping Neuroform stents may induce spontaneous thrombosis of intracranial aneurysms and facilitate parent artery reconstruction through flow remodeling and stent endothelialization. Double stent placement may be a viable option in dissecting or fusiform intracranial aneurysms that are not amenable to open surgical treatment or endovascular coil embolization.

Pneumopericardium and pneumomediastinum are rare presentations seen most commonly in the context of chest trauma or mechanical ventilation. Here we present a case of a spontaneous pneumopericardium and pneumomediastinum, which occurred in a young man with a recent coryzal illness and multiple Valsalva maneuvers in flight. Although the etiology of pneumopericardium and pneumomediastinum are well described in the literature, possible acute risks to flight personnel have not been previously documented.

The following article summarises the proceedings of the Travel Medicine Study Day run by the Haywood Club Tri-Service Medical Society at the Medical Society of London on 23 November 2006. The event was attended by over 50 serving and retired DMS personnel, including nurses, MSO's and medical officers and included talks on the historical contribution of the military medical services to the evolution of tropical medicine, the changing face of worldwide illness and insights into the behaviour of travellers that may increase their risk of illness.

Background: The improved accuracy of 64-multislice CT (MSCT) suggests that this technique may replace other non-invasive methods to detect clinically significant coronary atherosclerosis. The aim of the present study was to assess the clinical usefulness of in consecutive patients with suspected or proven coronary artery disease (CAD)., Methods: 64-MSCT was performed in 56 patients (age 56+/-16 years, 50 male) with suspected or proven CAD (35 patients with chest pain/positive provocative tests/risk factors), 18 with documented significant CAD, CABG surgery or stent implantation, 3 non-assessable with selective angiography because of peripheral vascular disease or large aneurysms of the ascending aorta., Results: One patient was excluded because of contrast extravasation. In 30/55 patients (54%) 64-MSCT excluded significant coronary stenoses; in 13/55 patients (24%) angiography and/or angioplasty were recommended to treat (3) 50% diameter stenoses shown by MSCT, a diagnosis confirmed in 9 (81.8%) of the 11 patients who underwent further investigations; 12/55 patients (22%) needed angiography or other preliminary non-invasive tests because 64-MSCT was of insufficient diagnostic quality. Predictors of a poor diagnostic quality of 64-MSCT were older age (64+/-8 vs. 55+/-11 years, p<0.007), diabetes mellitus (42% vs. 9%, p=0.017), previous angiography, angioplasty or CABG surgery (83% vs. 26%, p<0.0001), Agatston score>400 (75% vs. 21%, p<0.002)., Conclusion: 64-MSCT provided complete diagnostic coronary images sufficient for clinical decision making in the vast majority (78%) of a consecutive group of patients studied for suspected or proven CAD. Predictors of diagnostic failure were massive calcification, long-standing known coronary atherosclerosis or previous CABG/stent implantation, old age and diabetes mellitus.

Summary: We describe a case of a 75-year-old man who presented with acute onset of headache and subarachnoid hemorrhage and initial cerebral angiography was deemed "negative". In retrospect, a faint contrast collection was present adjacent to the right vertebral artery at the C1 level suspicious for a small dural arteriovenous fistula (dAVF). Follow-up angiography with selective microcatheter injections of the right vertebral artery and C1 radicular artery confirmed a complex dAVF with characteristically specific venous drainage patterns associated with a subarachnoid hemorrhage presentation. Subsequently, the cervical dAVF was treated with superselective glue embolization resulting in complete occlusion. Cervical dAVFs are extremely rare vascular causes of subarachnoid hemorrhage. Both diagnostic angiography and endovascular treatment of these lesions can be challenging, especially in an emergent setting, requiring selective evaluation of bilateral vertebral arteries and careful attention to their cervical segments. Although only a single prior case of a cervical dAVF presenting with subarachnoid hemorrhage has been successfully treated with embolization, modern selective transarterial techniques may allow easier detection and treatment of subtle pathologic arteriovenous connections.

Goals: This study characterizes cardiovascular autonomic function in women with irritable bowel syndrome (IBS), using standardized techniques., Background: Autonomic dysfunction is believed to contribute to abnormal gastrointestinal motility and visceral hypersensitivity in IBS. There is mounting evidence of generalized impairment of autonomic activity in patients with IBS., Study: Thirty women aged 39 years (95% C.I. 25-53 years) diagnosed with IBS, and 30 age-matched healthy women were studied. The ratio of low frequency to high frequency heart rate variability domains (LF:HF ratio) was used to represent cardiac sympathovagal activity, and orthostatic testing and sustained isometric handgrip exercise were used as sympathetic stimuli. Parasympathetic activity was represented by the expiratory to inspiratory R-R interval (E:I) ratio during deep breathing at 6 minutes., Results: LF:HF responses to handgrip exercise (316%, C.I. 134% to 498% vs. 107%, C.I. 15% to 153%; P < 0.05) and orthostatic testing (648%, C.I. 520% to 904% vs. 330%, C.I. 140% to 520%; P < 0.05) were higher in IBS patients than controls, and the E:I ratio was significantly lower (1.47, C.I. 1.33-1.61 vs. 1.20, C.I. 1.14-1.26; P < 0.01)., Conclusions: Autonomic cardiovascular function is impaired in IBS, manifest as attenuated cardio-vagal tone, and relative sympathetic excess during stimulated conditions.

The irritable bowel syndrome (IBS) is characterized by alimentary and non-alimentary symptoms; the aim of this study was to assess the clinical value and discriminant function of non-alimentary symptoms in the irritable bowel syndrome. Alimentary and non-alimentary symptoms, estimated daily dietary fibre intakes, ability to express personal feelings, anxiety and depression ratings, and life events and difficulties inventories were compared in 128 hospital out-patients with IBS and 113 age and sex matched control subjects not seeking health care, randomly recruited from the community. Alimentary symptoms correlated closely with those non-alimentary symptoms often associated with the hyperventilation syndromes, difficulties in expressing personal feelings and anxiety, and depression ratings. Life events and difficulties, and estimated daily dietary fibre intakes did not differ significantly between patients and controls. With the exception of abdominal bloating, no significant gender differences were observed in IBS symptoms in either the IBS or control groups. The irritable bowel syndrome is one facet of a more general condition of illness behaviour which includes the hyperventilation syndrome and an inassertiveness in expressing personal feelings. Though non-alimentary symptoms did not improve diagnostic accuracy beyond that achieved by a combination of alimentary symptoms, their recognition provides alternative approaches to the management of refractory IBS.

The Michigan alcoholism screening test was used to assess the prevalence of alcohol problems in 142 patients aged between 18 and 60 years consulting a general practitioner. Previous and/or current alcohol problems were identified in 33% of men and 4% of women. Unemployment was found to be significantly associated with alcohol problems in the men of the study group. The higher proportion of patients with alcohol problems requesting consultation compared with those without such problems did not appear to be associated with a specific presenting complaint.Screening for alcohol problems should be undertaken in all patients consulting a general practitioner if early detection and intervention are to be achieved.