Commentary: Dynamic hip screw fixation versus multiple screw fixation for intracapsular hip fracture

As the elderly population increases, the incidence of fragility hip fracture also increases. By 2050, the incidence is predicted to be around 4.5 million.1 Treatment of intracapsular hip fractures depends on many factors including patient age, fracture pattern, degree of fracture displacement and comorbidities. For younger patients (<65 years of age), the femoral head should be preserved using an internal xation method, either multiple screw xation or dynamic hip screw (DHS), to avoid any long-term complication of arthroplasty.2 For elderly patients, both internal xation methods are suitable for non- displaced intracapsular hip fractures. Nonetheless, arthroplasty is preferable for displaced intracapsular hip fractures because of a lower reoperation rate and better functional outcome.3 In this issue, Jettoo et al.4 compared DHS xation with multiple screw xation for intracapsular hip REFERENCES fractures in terms of complications and conversion to hemiarthroplasty or total hip arthroplasty. DHS xation resulted in more medical complications than multiple screw xation, whereas multiple screw xation was associated with a higher conversion rate to arthroplasty. DHS xation has more disadvantages related to soft-tissue stripping and blood loss.5,6 It is important to emphasise that the reasons for revision surgery are multifactorial and not due to the implant/ xation method alone.7,8 Accurate fracture reduction is a prerequisite to satisfactory bone union.9 It is worth noting that the study by Jettoo et al.3 was a retrospective review based on hospital data. The fracture classi cation, degree of fracture displacement, and bone quality were not clearly documented. The evidence was not suf cient to support the superiority of DHS xation over multiple screw xation in treating intracapsular hip fractures.published_or_final_versio

Lithium ion alters Ins(1,4,5)P3 production and mobilisation of intracellular free calcium in k-agonist stimulated rat ventricular myocytes

The effect of lithium ion on the generation of inositol phosphates and the mobilisation of intracellular free calcium in isolated adult rat ventricular myocytes stimulated with k-agonist was studied. Dynorphin1-13 stimulated an increase in the levels of Inositol 1,4,5-trisphosphate (InsP3) and intracellular free calcium ([Ca2+ ]i). Preincubation of the ventricular myocytes with lOmM Li+ for 20 minutes prior to stimulation by dynorphin1-13 reduce the increase of both InsP3 and [Ca2+]i. This effect of Li+ was not seen if 5mM inositol was also present during preincubation. It is concluded that (1) the inhibition of the k-agonist stimulated increase in InsP3 and [Ca2+]i, in Li+-pretreated ventricular myocytes was a result of a depletion of intracellular inositol, due probably to the inhibition by Li+ of inositol monophosphatase which participates in the recycling of intracellular inositol, and (2) the k-agonist induced increase in [Ca2+]i is a consequence of the production of InsP3 since altering the kinetics of production of this compound also altered [Ca2+]i.published_or_final_versio

Miniaturized Via-Free Magneto-Electric Dipole Antenna Fed by Substrate Integrated Coaxial Line on Reactive Impedance Surface

A wideband via-free magneto-electric (ME) dipole antenna is conceived for millimeter wave band applications. Herein, the electric dipole patch and a half-wavelength radiating slot are excited in phase on the patch layer by a substrate integrated coaxial line (SICL) to fulfill the complementary conditions as a ME dipole. The proposed antenna omits the deployment of the vertically oriented shorted patch, which relieves the typical quarter-wavelength height constraint and fabrication complexity of the conventional ME dipole antennas. The antenna is further loaded with the capacitive reactive impedance surface (RIS) to achieve size miniaturization and bandwidth enhancement. The finalized dimension (excluding the RIS) is 0.36 λ0 × 0.48 λ0 × 0.13 λ0, where λ0 denotes the wavelength in free-space at the center frequency. A wide impedance bandwidth of 64.8% (17.1 GHz - 33.5 GHz) is achieved for SWR ≤ 2, in which the antenna gain varies from 5.9 dBi to 8.8 dBi. Besides, a consistent unidirectional radiation pattern can be observed across the operating frequency band. In the sequel, the same antenna is aggregated into an 8-element linear array which is fed by a designated 8-way SICL network

Miniaturized Via-Free Magneto-Electric Dipole Antenna Fed by Substrate Integrated Coaxial Line on Reactive Impedance Surface

A wideband via-free magneto-electric (ME) dipole antenna is conceived for millimeter wave band applications. Herein, the electric dipole patch and a half-wavelength radiating slot are excited in phase on the patch layer by a substrate integrated coaxial line (SICL) to fulfill the complementary conditions as a ME dipole. The proposed antenna omits the deployment of the vertically oriented shorted patch, which relieves the typical quarter-wavelength height constraint and fabrication complexity of the conventional ME dipole antennas. The antenna is further loaded with the capacitive reactive impedance surface (RIS) to achieve size miniaturization and bandwidth enhancement. The finalized dimension (excluding the RIS) is 0.36 &#x03BB;0 &#x00D7; 0.48 &#x03BB;0 &#x00D7; 0.13 &#x03BB;0, where &#x03BB;0 denotes the wavelength in free-space at the center frequency. A wide impedance bandwidth of 64.8% (17.1 GHz - 33.5 GHz) is achieved for SWR &#x2264; 2, in which the antenna gain varies from 5.9 dBi to 8.8 dBi. Besides, a consistent unidirectional radiation pattern can be observed across the operating frequency band. In the sequel, the same antenna is aggregated into an 8-element linear array which is fed by a designated 8-way SICL network. Finally, an active simulation has been performed to verify the ability of the array in beam scanning

Infection after fracture osteosynthesis – Part II: Treatment

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Anatomic variations of neurovascular structures of the ankle in relation to arthroscopic portals: a cadaveric study of Chinese subjects.

PURPOSE: To investigate anatomic variations of neurovascular structures in the ankle and the safety margin for arthroscopic portals. METHODS: 11 left and 12 right ankles from 8 female and 15 male fresh cadavers of Chinese ethnicity aged 53 to 88 (mean, 68) years were used. The ankle was standardised in a plantigrade position, zero-degree inversion, and neutral rotation. Four ankle portals, namely anteromedial (AM), anterolateral (AL), posteromedial (PM) and posterolateral (PL), were identified using 23-gauge needles. Skin and subcutaneous fat were dissected from the underlying fascia to visualise neurovascular structures. Distances were measured from: (1) the AM portal to the saphenous vein and nerve and its branches, (2) the AL portal to branches of the superficial peroneal nerves, of which the lateral one was labelled as the intermediate dorsal cutaneous branch and the medial one as the medial dorsal cutaneous branch, (3) the PM portal to the posterior tibial neurovascular bundles, and (4) the PL portal to the sural nerve. RESULTS: The distances from (1) the AM portal to branches of the great saphenous vein and nerve, and (2) the AL portal to the intermediate dorsal cutaneous branch of the superficial peroneal nerve were short and may be an anatomic hazard. Variations were significant among the cadavers in terms of distances of the portals to the neurovascular structures. CONCLUSION: In Chinese cadavers, variations of neurovascular structures are significant. Care must be taken to avoid inadvertent injury during ankle arthroscopy.published_or_final_versio

Infection after fracture osteosynthesis – Part I: Pathogenesis, diagnosis and classification

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Hyaluronic Acid Instillation Following Arthroscopic Anterior Cruciate Ligament Reconstruction: A Double-blinded, Randomised Controlled Study.

PURPOSE: To assess the effect of hyaluronic acid instillation after arthroscopic anterior cruciate ligament (ACL) reconstruction for improving pain, range of movement, and function of the knee. METHODS: 28 men and 4 women underwent arthroscopic ACL reconstruction for isolated ACL rupture (partial or complete) and instability after recreational sports injury 2 to 120 months earlier. They were randomised to undergo arthroscopic ACL reconstruction followed by intra-articular viscoseal instillation (13 men and 3 women) or arthroscopic ACL reconstruction alone (15 men and 1 woman). The knee injury osteoarthritis outcome score (for pain, symptoms, activities of daily living, sport and recreation function, and quality of life), range of movement, knee circumference, and analgesic use were assessed on days -1, 1, and 2, and weeks 2, 6 and 12. RESULTS: Patient demographics were similar at baseline. At postoperative days 1 and 2, all subscales of the knee injury osteoarthritis outcome score (except for quality of life) were significantly higher in the viscoseal group. At weeks 2, 6, and 12, improvement in both groups equalised. Knee swelling (change in knee circumference) was significantly less in the viscoseal group at days 1 and 2 (p=0.009 and p=0.038, respectively, Mann-Whitney U test). Only one patient in the viscoseal group had a limited range of movement. No patient developed any adverse reaction. CONCLUSION: Intra-articular viscoseal instillation improved pain control and swelling 2 days after arthroscopic ACL reconstruction.published_or_final_versio

Preconditioning with Porphyromonas gingivalis lipopolysaccharide may confer cardioprotection and improve recovery of the electrically induced intracellular calcium transient during ischemia and reperfusion

Background and Objective: Porphyromonas gingivalis lipopolysaccharide (LPS) is a ligand for cell surface toll-like receptors (TLR), TLR2 and TLR4 while stimulation of either leads to cardioprotection. We hypothesized that: (1) pretreatment with P. gingivalis LPS at appropriate concentrations would induce cardioprotection against injury induced by ischemia and reperfusion; and (2) P. gingivalis LPS pretreatment at cardioprotective concentrations may reduce Ca2+ overload, which is a precipitating cause of injury, and improve recovery of contractile function. Material and Methods: Male Sprague-Dawley rats were randomly selected to receive intraperitoneal saline or hot phenol-water-extracted P. gingivalis LPS at 0.2, 0.5, 1.0, 2.0 or 4.0 mg/kg 24 h before the experiment. The hearts were isolated and subjected to regional ischemia by coronary artery ligation followed by reperfusion. In isolated rat ventricular myocytes, the cytosolic Ca2+ level and the electrically induced intracellular calcium (E[Ca2+]i) transient, which reflects contractile function, were determined after pretreatment with a cardioprotective dose of P. gingivalis LPS. Results: Pretreatment with 0.5 mg/kg P. gingivalis LPS significantly reduced, while pretreatment with 1.0-4.0 mg/kg significantly increased infarct size. The Ca2+ overload induced by ischemia-reperfusion was attenuated in myocytes from rats pretreated with 0.5 mg/kg P. gingivalis LPS. Pretreated myocytes also showed an increased amplitude of the E[Ca2+]i transient, no prolongation of the time to reach the peak E[Ca2+]i transient and shorter 50% decay time during reperfusion. Conclusion: At a dosage of 0.5 mg/kg, P. gingivalis LPS confers cardioprotection against ischemia-reperfusion-induced injury and improved intracellular E[Ca2+]i transient recovery, hence improving myocyte contractile recovery. © 2009 John Wiley & Sons A/S.postprin

Effect of duration of ischaemia on infarct volume in the rat

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