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Molecules containing short-lived, radioactive nuclei are uniquely positioned to enable a wide range of scientific discoveries in the areas of fundamental symmetries, astrophysics, nuclear structure, and chemistry. Recent advances in the ability to create, cool, and control complex molecules down to the quantum level, along with recent and upcoming advances in radioactive species production at several facilities around the world, create a compelling opportunity to coordinate and combine these efforts to bring precision measurement and control to molecules containing extreme nuclei. In this manuscript, we review the scientific case for studying radioactive molecules, discuss recent atomic, molecular, nuclear, astrophysical, and chemical advances which provide the foundation for their study, describe the facilities where these species are and will be produced, and provide an outlook for the future of this nascent field.
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The medial femur condyle (MFC) cortico-periosteal flap is a popular flap for bone reconstruction. The use of a chimeric version of this flap with a skin island has been described, but anatomical arterial variation can occur that prevent its harvest. Furthermore, the donor area of the skin paddle has been debated as poor because of the scarring in a visible area and because of the difficulty in obtaining pliable thin skin. We present a fabricated chimeric MFC cortico-periosteal flap joined with a superficial inferior epigastric perforator (SCIP) flap to reconstruct and augment a sclerotic and insufficient small clavicula with the skin paddle acting as a monitor and as a substitute for the overlying skin. A 52-year-old female patient had a history of multiple refractures of the right hypoplastic clavicle with a diameter of 7 mm, resulting in a sclerotic bone with a fibrotic scar. The reconstruction was done in one surgical session using a cortico-periosteal flap from the left medial condyle and a thin SCIP flap from the left groin. The area of the clavicle to be reconstructed was 3 cm, and the direct overlying skin (approximately 6 × 3 cm) was severely scarred and painful. The MFC flap was 5 × 4 cm, while the SCIP flap was 7 × 3.5 cm. The SCIP flap artery was anastomosed on the table end-to-side to the descending genicular (DG) artery of the MFC, and the vein was anastomosed end-to-end to a comitans vein of the DG artery. The flap fully survived after an initial congestion. At 12 months, we observed a satisfactory reconstruction of the clavicle with an enhanced diameter of 12 mm. The patient recovered full function of the shoulder with no pain. Using a fabricated chimeric flap composed of a medial femoral condyle and a superficial circumflex artery perforator flap may be an additional option for tailored reconstruction of complex osteo-cutaneous defect of clavicle.
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Retalho Perfurante , Procedimentos de Cirurgia Plástica , Feminino , Humanos , Pessoa de Meia-Idade , Retalho Perfurante/irrigação sanguínea , Artéria Ilíaca/cirurgia , Clavícula/cirurgia , Fêmur/cirurgiaRESUMO
Dialuminum monoxide, Al2O, has been investigated in the laboratory at mid-IR wavelengths around 10 µm at high spectral resolution. The molecule was produced by laser ablation of an aluminum target with the addition of gaseous nitrous oxide, N2O. Subsequent adiabatic cooling of the gas in a supersonic beam expansion led to rotationally cold spectra. In total, 848 ro-vibrational transitions have been assigned to the fundamental asymmetric stretching mode ν3 and to five of its hot bands, originating from excited levels of the ν1 symmetric stretching mode and the ν2 bending mode. The measurements encompass 11 vibrational energy states (v1 v2l v3). The ro-vibrational transitions show spin statistical line intensity alternation of 7:5, which is caused by two identical aluminum nuclei of spin I = 5/2 at both ends of the centrosymmetric molecule of structure Al-O-Al. The less effective cooling of vibrational states in the supersonic beam expansion allowed measurement of transitions in excited vibrational states at energies of 1000 cm-1 and higher, while rotational levels within vibrational modes exhibited thermal population, with rotational temperatures around Trot = 115 K. Molecular parameters for 11 vibrational states were derived, including rotation and centrifugal distortion constants and l-type doubling constants for the states (v1 v2l v3) = (0 11 0) and (0 11 1) and an l-type resonance between the states (0 20 0) - (0 22 0) and (0 20 1) - (0 22 1). From the experimental results, rotational correction terms and the equilibrium bond length re were derived. The measurements were supported and guided by high-level quantum-chemical calculations that agree well with the derived experimental results.
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Recently, a breakthrough has been achieved in laser-spectroscopic studies of short-lived radioactive compounds with the first measurements of the radium monofluoride molecule (RaF) UV/vis spectra. We report results from high-accuracy ab initio calculations of the RaF electronic structure for ground and low-lying excited electronic states. Two different methods agree excellently with experimental excitation energies from the electronic ground state to the 2Π1/2 and 2Π3/2 states, but lead consistently and unambiguously to deviations from experimental-based adiabatic transition energy estimates for the 2Σ1/2 excited electronic state, and show that more measurements are needed to clarify spectroscopic assignment of the 2Δ state.
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Background and Objectives: Retrograde free venous flaps represent a separate entity among free venous flaps: their physiology is still unclear, but they provide an immediate visible refill after reconnection, with a similar behaviour to conventional flaps. Therefore, the dimensions and the indications of these flaps can be extended beyond what was previously believed, and they can be easily customized, including with respect to tendons and nerves. Nevertheless, they are still debated and regarded as unsafe. Materials and Methods: From 2012 to 2019, we performed 31 retrograde free venous flaps on 31 patients to reconstruct hands, digits, and in one case the heel. All the flaps were arterialized in a retrograde manner; the donor site was the forearm in 28 cases, the foot in 2 cases, and the calf in 1 case. We recorded the size, vein architecture, donor site, donor artery, donor morbidity, function for composite and non-composite flaps, immediate complications, late complications, survival rate, and the number of revisions. We recorded the hand function when appropriate. A total of 10 flaps were also intraoperatively studied with indocyanine green to monitor their hemodynamical behaviour. Results: All the patients were followed for an average of 8 months (6−15). The flap dimensions ranged from 6 cm2 to 136 cm2. All the flaps, except two that had complete necrosis, survived. Two flaps had partial necrosis. There was no correlation between necrosis and the size of the flap, with one case of necrosis and one of partial necrosis in the small flaps (<10 cm2). None of the cases with partial necrosis needed a new flap. Two flaps developed a late arterio-venous shunt that was ligated. Conclusions: The retrograde free venous flaps proved to be a useful tool for complex reconstructions of the hand and extremities. They can provide a large island of pliable skin and composite tissue with tendons and nerves, but surgeons must be aware of some caveats.
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Traumatismos da Mão , Lesões dos Tecidos Moles , Antebraço/cirurgia , Traumatismos da Mão/cirurgia , Humanos , Necrose , Lesões dos Tecidos Moles/cirurgia , Retalhos Cirúrgicos/irrigação sanguínea , Veias/cirurgiaRESUMO
A multipass optics (MPO) system is used to increase the optical path length in a limited volume. Well-known concepts such as the White-type cell and the Herriott-type cell are used in many applications. The optical path in these cells leaves a large portion of the cell volume unused. In contrast, MPO systems with astigmatic mirrors have significantly more beam passes per volume, but because of their reduced symmetry along the beam axis they are much more sensitive to misalignment. Our goal is to develop MPO systems that have both: the high beam densities of astigmatic MPO systems and the optical robustness of Herriott-type optics. We show that linearized optical ring resonators, which can be constructed by means of simple 2×2 optical ABCD-matrices, lead to suitable solutions. The concept is demonstrated using a MPO system with a base length of 150 mm and a total beam path length of 19.2 m, optimized for laser beams of 10 µm wavelength. The volume of the cell is 295cm3 with a beam density that is four times higher compared to a standard Herriott-type cell.
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The tracking of symmetry-breaking events in space is a long-lasting goal of astrochemists, aiming at an understanding of homochiral Earth chemistry. One current effort at this frontier aims at the detection of small chiral molecules in the interstellar medium. For that, high-resolution laboratory spectroscopy data is required, providing blueprints for the search and assignment of these molecules using radioastronomy. Here, we used chirped-pulse Fourier transform microwave and millimeter-wave spectroscopy and frequency modulation absorption spectroscopy to record and assign the rotational spectrum of the chiral aromatic molecule styrene oxide, C6H5C2H3O, a relevant candidate for future radioastronomy searches. Using experimental data from the 2-12, 75-110, 170-220, and 260-330 GHz regions, we performed a global spectral analysis, which was complemented by quantum chemistry calculations. A global fit of the ground state rotational spectrum was obtained, including rotational transitions from all four frequency regions. Primary rotational constants as well as quartic and sextic centrifugal distortion constants were determined. We also investigated vibrationally excited states of styrene oxide, and for the three lowest energy vibrational states, we determined rotational constants including centrifugal distortion corrections up to the sextic order. In addition, spectroscopic parameters for the singly-substituted 13C and 18O isotopologues were retrieved from the spectrum in natural abundance and used to determine the effective ground state structure of styrene oxide in the gas phase. The spectroscopic parameters and line lists of rotational transitions obtained here will assist future astrochemical studies of this class of chiral organic molecules.
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BACKGROUND: The aim of this study was to evaluate the effectiveness and safety of free corticoperiosteal medial femoral condyle (MFC) flap for ankle, hindfoot and midfoot reconstruction in patients with recalcitrant nonunion. METHODS: Patients who underwent ankle and foot reconstruction using the MFC flap at our clinic were recruited for assessment of the union rate, time to union and functional outcome. Furthermore, a clinical and radiological examination of the donor knee was performed using both computed tomography and magnetic resonance imaging. RESULTS: Thirteen patients with a mean follow-up time of 2.5 years were included; 10 of them had a previously failed ankle and foot arthrodesis. Union was achieved in 11 patients in an average time of 10 months after MFC flap surgery. Donor site morbidity was minor with no radiological evidence for soft tissue or bone complication. CONCLUSION: MFC flaps are a useful and safe reconstructive tool and may be considered after failed ankle and foot arthrodesis.
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Transplante Ósseo/métodos , Fêmur/transplante , Fraturas não Consolidadas/diagnóstico por imagem , Fraturas não Consolidadas/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Adulto , Articulação do Tornozelo/cirurgia , Artrodese , Feminino , Retalhos de Tecido Biológico , Humanos , Articulação do Joelho , Masculino , Pessoa de Meia-Idade , Morbidade , Radiografia , Estudos RetrospectivosRESUMO
The ν3 antisymmetric stretching mode of disilicon-carbide, Si2C, was studied using a narrow line width infrared quantum cascade laser spectrometer operating at 8.3 µm. The Si2C molecules were produced in an Nd:YAG laser ablation source from a pure silicon sample with the addition of a few percent methane diluted in a helium buffer gas. Subsequent adiabatic expansion was used to cool the gas down to rotational temperatures of a few tens of kelvin. A total of 183 infrared transitions recorded in the spectral range between 1200 and 1220 cm-1 were assigned to the fundamental ν3 mode of Si2C. In addition, pure rotational transitions of Ka = 1 and 2 between 278 and 375 GHz were recorded using a supersonic jet spectrometer for submillimeter wavelengths. Molecular parameters for the ( v1 v2 v3) = (001) vibrationally excited state were derived and improved molecular parameters for the vibrational ground-state (000) were obtained from a global fit data analysis, which includes our new laboratory data and millimeter wavelength data from the literature. We found the rotational levels Ka = 0 and Ka = 2 in the vibrationally excited (001) state being perturbed by a Coriolis-type interaction with energetically close lying levels of the symmetric stretching and triple-excited bending mode (130). The data analysis was supported by quantum chemical calculations performed at the coupled-cluster level of theory. All experimental results were found to be in excellent agreement with the theory.
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Three-wave mixing spectroscopy of chiral molecules, which exist in left-handed and right-handed conformations, allows for enantioselective population transfer despite random orientation of the molecules. This is based on constructive interference of the three-photon pathways for one enantiomer and the destructive one for the other. We prove here that three mutually orthogonal polarization directions are required to this end. Two different dynamical regimes exist to realize enantioselective population transfer, and we show that they correspond to different phase conditions in the three-wave mixing. We find the excitation scheme used in current rotational three-wave mixing experiments of chiral molecules with C1 symmetry to be close to optimal and discuss the prospects for rovibrational three-wave mixing experiments of axially chiral molecules. Our comprehensive study allows us to clarify earlier misconceptions in the literature.
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INTRODUCTION: There is growing evidence of the superior ability of muscular tissue to clear bacterial bone infection. Unfortunately, in the hand, there are almost no small local muscular flaps, and muscular transfers to the hand are mainly microsurgical free transfers. In this report, we present the results of the use of a chimeric posterior interosseous flap including part(s) of the forearm muscles to treat osteomyelitis and soft tissue defect of hand from a series of patients. PATIENTS AND METHODS: Four male patients with an average age of 32 years (range 20-46 years), were affected by acute osteomyelitis in hand. Previous fracture fixation with percutaneous K-wires was the cause of bone infection in three case. In one case, the osteomyelitis was a consequence of an open fracture. The bones affected were four metacarpals and one proximal phalanx, all with a minimal cortical defect (from the K-wire) obscuring a larger medullary infection, which required extensive bone and overlying soft tissue debridement, leaving a soft tissue defect to be reconstructed of size ranging from 2 x 4 cm to 5 x 7 cm. The soft tissue defects were due to concomitant superficial infection and consequent debridement. All patients were treated with bone debridement and a chimeric posterior interosseous flap, which included part of the extensor digiti minimi and/or extensor carpi ulnaris to fill the intramedullary canal of the bones. No fixation of bone was necessary. RESULTS: The skin paddle of the flaps ranged from 2 x 5 cm to 5 x 6 cm, replicating the defect area, plus a teardrop tail of skin circa 1.5 cm wide and as long as the pedicle of the flap. The muscular components of the flaps used to fill the intramedullary canals ranged from 1 x 1 x 1.5 cm to 1.5 x 1.5 x 4 cm. All flaps survived and osteomyelitis resolved in all cases without major complications. At the final follow-up at 16 months (range 12-26 months), assessment of the hands using TAM, Power Grip and Key Pinch Strength measurements and, where appropriate, Kapandji scores, demonstrated satisfactory hand function. CONCLUSION: The chimeric posterior interosseous flap including part of the muscles of the forearm may be a robust solution for augmenting the flap bulk and may be used in cases of severe osteomyelitis of the hand.
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Fraturas Ósseas/complicações , Traumatismos da Mão/complicações , Osteomielite/cirurgia , Lesões dos Tecidos Moles/cirurgia , Retalhos Cirúrgicos/transplante , Doença Aguda , Adulto , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/diagnóstico , Fraturas Ósseas/cirurgia , Traumatismos da Mão/diagnóstico , Traumatismos da Mão/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Retalho Miocutâneo/irrigação sanguínea , Retalho Miocutâneo/transplante , Osteomielite/diagnóstico , Osteomielite/etiologia , Prognóstico , Medição de Risco , Estudos de Amostragem , Lesões dos Tecidos Moles/diagnóstico , Lesões dos Tecidos Moles/etiologia , Retalhos Cirúrgicos/irrigação sanguínea , Resultado do Tratamento , Cicatrização/fisiologia , Adulto JovemRESUMO
INTRODUCTION: None of the existing treatments in the management of painful end-neuromas of the superficial branch of the radial nerve (SBRN) has been proven superior due to high levels of pain relapse. Fat grafts enriched with the stromal vascular fraction (SVF) could act as a mechanic barrier with biological effects decreasing the resorption rate and boosting the graft's regenerative potential. This study describes the novel surgical treatment technique of SVF-enriched fat grafting. PATIENTS AND METHODS: In this clinical study, five consecutive patients treated for painful end-neuromas of the SBRN between 2012 and 2013 were analyzed retrospectively. Microsurgical resection of end-neuromas followed by SVF-enriched fat grafting around the nerve stump was performed in all patients. Five different pain modalities and various predictors were compared pre- and up to 36 months postoperatively. RESULTS: Pain reduction observed at 2 months after surgery was constant over time, though not statistically significant compared to preoperative levels. Spontaneous pain could be reduced from 1.6 ± 0.55 to 1.2 ± 1.1 (p = 0.414), spikes from 2.2 ± 1.3 to 1.4 ± 1.34 (p = 0.180), hyperaesthesia from 1.6 ± 1.14 to 1.2 ± 1.64 (p = 0.713), tap pain from 2.8 ± 0.45 to 1.8 ± 1.3 (p = 0.197) and motion pain from 2.8 ± 0.45 to 1.4 ± 1.34 (p = 0.066). An improvement in overall pain reduction could be observed from 2.2 ± 0.97 to 1.4 ± 1.26 3 years after the surgery (p = 0.104). CONCLUSION: SVF-enriched fat grafting represents another alternative to numerous available treatments of painful end-neuromas of the SBRN. Our preliminary results could not show any significant difference in pain reduction following SVF-enriched fat grafting. Further larger trials are required in order to evaluate the therapeutic potential of SVF-enriched fat grafting.
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Neuroma/cirurgia , Neoplasias do Sistema Nervoso Periférico/cirurgia , Nervo Radial/cirurgia , Gordura Subcutânea/transplante , Adulto , Idoso , Seguimentos , Humanos , Lipectomia , Masculino , Pessoa de Meia-Idade , Neuralgia/diagnóstico , Neuralgia/etiologia , Neuralgia/cirurgia , Neuroma/complicações , Medição da Dor , Neoplasias do Sistema Nervoso Periférico/complicações , Estudos Retrospectivos , Gordura Subcutânea/citologia , Resultado do TratamentoRESUMO
Guided by high-level quantum-chemical calculations at the CCSD(T) level of theory, the first polyatomic germanium-carbon cluster, linear Ge2C3, has been observed at high spectral resolution in the gas phase through its remarkably complex fundamental antisymmetric C-C stretching mode ν3 located at 1932 cm(-1). The observation of a total of six isotopic species permits the derivation of a highly accurate value for the equilibrium Ge-C bond length. The present study suggests that many more Ge-C species might be detectable in the future using a combination of laser-ablation techniques for production and high-resolution infrared and/or microwave techniques for spectroscopic detection.
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The ν2 lowest bending mode of linear C3 and of all its 13C-substituted isotopologues was recorded using a terahertz-supersonic jet spectrometer in combination with a laser ablation source. Sixty-five ro-vibrational transitions between 1.8 and 1.9 THz have been assigned to linear C12C12C12, C12C12C13, C12C13C12, C13C13C12, C13C12C13, and C13C13C13. For each isotopologue, molecular parameters were obtained and the C-C-bond length was derived experimentally. All results are in excellent agreement with recent ab initio calculations [B. Schröder and P. Sebald, J. Chem. Phys. 144, 044307 (2016)]. The new measurements explain why the interstellar search for singly substituted C12C12C13 has failed so far. A spectral line list with recommended transition frequencies based on global data fits is given to foster future interstellar detections.
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PURPOSE: Although the literature is encouraging with regard to the survival rate of arterialized free venous flaps, previously reported difficulty in healing owing to early venous congestion and subsequent epidermolysis continues to prevent their widespread application. We report 14 arterialized free venous flaps for primary reconstruction of the hand, with inflow in the arterialized vein running against the valves. METHODS: Between February 2010 and May 2012, we performed 14 arterialized free venous flaps, each of which included at least 2 veins running in parallel. The arterialized vein was anastomosed in a retrograde manner, with the inflow running against the valves. All flaps were customized with regard to dimension, shape, quality of skin, pedicle length, vessel size, inclusion of additional anatomical structures, and donor site. The flaps were used to cover small, medium, and large defects; 2 flaps were larger than 100 cm(2). Three flaps were injected with indocyanine green on the table after harvesting, to visualize the vascular tree of the flap. These 3 flaps were then monitored with systemic indocyanine green injection and an infrared camera for 3 days postoperatively. RESULTS: All but 1 flap survived. Venous congestion and epidermolysis were observed in 2 small flaps. The flaps injected with indocyanine green displayed a ramified vascular tree with no arteriovenous flow-through phenomenon. CONCLUSIONS: Arterialized free venous flaps with retrograde arterial flow offer thin and pliable coverage that fits easily around the contours of the hand. They are easy to harvest, with little donor site morbidity. Tendons or nerves can be incorporated for reconstruction of composite defects. CLINICAL RELEVANCE: Our series suggests the possibility of routine use of a free venous flap with retrograde arterial flow for reconstruction of the hand. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.
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Traumatismos da Mão/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/irrigação sanguínea , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Veias/cirurgiaRESUMO
We report on the detection of the (10(0)1) â (00(0)0) vibrational band of gas-phase C3 and the two of its mono (13)C substituted isotopologs in the infrared region around 3200 cm(-1). Additionally, the associated hot band (11(1)1) â (01(1)0) has been assigned for the parent isotopolog. Spectra have been recorded using a supersonic jet spectrometer with a laser ablation source in combination with a continuous-wave optical parametric oscillator as radiation source. High-level quantum-chemical ab initio calculations have been performed and used to assist the assignment. A combined fit for the vibrational states of C3 found in this study has been done together with previously reported high-resolution data to increase the accuracy of the molecular parameters, especially for the ground state. The vibrational energies are 3260.126, 3205.593, and 3224.751 cm(-1) for the (10(0)1) state of C3, (12)C(13)C(12)C, and (13)C(12)C(12)C, respectively. The (11(1)1) state of C3 has been found to be at 3330.509 cm(-1).
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We recently reported a small study at the Federation of European Societies for Surgery of the hand, which was entitled 'What is secondary flexor tendon surgery'? This study concluded that 'secondary flexor tendon surgery' was a generic name encompassing a multitude of pathologies. Between 10% and 15% of cases exhibited pathology of the skin and subcutaneous fat and required flap reconstruction of these tissues. Skin replacement may be used prophylactically at primary surgery or become necessary at secondary surgery after release of scar contractures, to achieve cover of vital structures. The long-term problem of skin deficiency relating to flexor tendon function is one of loss of extension from longitudinal scar shortening of the integument, even if the flexor tendons are primarily concerned with bending the digits, not straightening them. This loss of extension can only be tolerated in a hand to a certain degree without significant loss of function. This paper is largely an analysis of the flaps available and suitable for different degrees of skin deficiency and at different places along the course of the flexor system. It attempts to dispel the idea that 'any flap will do' provided the flexors are adequately covered.
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As primary repair of divided flexor tendons becomes more common, secondary tendon surgery becomes largely that of the complications of primary repair, namely ruptured and adherent repairs. These occur with an incidence of each in most reported series world-wide of around 5%, with these problems having changed little in the last two decades, despite strengthening our suture repairs. Where the primary referral service is less well-developed, and as a more occasional occurrence where primary treatment is the routine, the surgeon faces different problems. Patients arrive at a hand unit variable, but longer, times after the primary insult, having had no, or bad, previous treatment. Sometimes the situation is the same, viz. an extended finger with no active flexion, but now no longer amenable to primary repair. Frequently, it is much more complex as a result of injuries to the other tissues of the digit and, also, as a result of the unaided healing process within the digit in the presence of an inactive flexor system. We present our experience in dealing with ruptured repairs, tethered repairs and pulley incompetence.
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We clarify the claim to the authorship of the first description of the heterodigital neurovascular island flap, describe different variants and present a series of 15 cases with clinical examples.
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Autoria , Traumatismos dos Dedos , Humanos , Traumatismos dos Dedos/cirurgia , Retalhos Cirúrgicos/cirurgiaRESUMO
The microsurgical replantation of incorrectly stored and transported amputates is generally considered impossible and without prospects of success. In particular, this applies to amputates that show cold damage due to the freezing of tissue. We present a case of successful replantation of an amputated finger pulp frozen in ice. We provide an overview of the literature on the subject of incorrect storage of amputates and the prospects of success for replantation.