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1.
Physiol Res ; 71(Suppl 1): S107-S113, 2022 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-36592446

RESUMEN

Arterial branches to the uterus and ovaries that pass through the mesosalpinx contribute significantly to the maintenance of the ovarian reserve. Especially arterial supply of the uterine tube is provided by a number of anastomoses between both the uterine and ovarian vessels. Knowledge on the morphologic peculiarities will allow to identify main contributors especially blood flow ultrasound examination for the purpose of ovary preserving surgery. This study aimed at identifying landmarks especially for so-called low-flow tubal vessels. Arteries of 17 female Thiel-embalmed bodies were studied along three preselected paramedian segments and measurements taken. A section was made through the center of the ovary perpendicular to uterine tube, then the mesosalpinx tissue distance was divided into 3 equivalent zones: upper, middle and lower thirds. The surface area of the mesosalpinx averaged 1088 ± 62 mm2. 47.7 ± 7.1 % of the mesosalpinx zones included macroscopically visible vessels. The lower third segment of mesosalpinx was the thickest averaging 2.4 ± 1.5 mm. One to three tubal branches were identified in the middle third of the mesosalpinx. Arterial anastomoses were found in the upper segment of the mesosalpinx, but no presence of a marginal vessel supplying the fallopian tube could be found. Statistically significant moderate positive correlations were established between the diameters of the mesosalpingeal arteries between the three zones. The mesosalpinx, uterine tube and the ovary form areas of segmental blood supply. Variants of tubal vessels appear to be a sparse source of blood supply.


Asunto(s)
Arterias , Trompas Uterinas , Femenino , Humanos , Trompas Uterinas/diagnóstico por imagen , Trompas Uterinas/irrigación sanguínea , Arterias/diagnóstico por imagen , Ovario/diagnóstico por imagen , Útero/diagnóstico por imagen , Útero/irrigación sanguínea , Flujo Sanguíneo Regional
2.
BMJ Mil Health ; 167(2): 89-92, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31326922

RESUMEN

INTRODUCTION: Displaced unstable pelvic injuries are life threatening and require rapid reduction and stabilisation, typically achieved with an external fixator. Recently, the benefits of supra-acetabular pins have been proven; however, these are usually inserted under fluoroscopic guidance. In austere environments and in extremis, this facility is limited and fixation using anatomical landmarks is required. Thus, the aim of this study is to determine the relative position of the supra-acetabular bone to the crestal plane and examine its consistency in military-aged European personnel. METHODS: A radiological review of 50 randomised pelvic CT scans in European patients aged 18-30 years from a Level 1 trauma centre was performed. The CT scans were analysed using 3D rendering software. The relative position of the supra-acetabular bone to the crestal plane was determined. RESULTS: The supra-acetabular bone relative to the crestal plane was approximately 28° caudal and 24° medial to the crestal plane. The mean minimum distance from the pin's entry point to the sciatic notch was approximately 73 mm. There were no differences noted between genders or hemipelvic side. CONCLUSIONS: The supra-acetabular bone maintains a consistent relative position to the crestal plane. Thus, with the surgeon's thumb on the anterior superior iliac spine (ASIS) and index finger on the iliac tubercle, defining the crestal plane, a supra-acetabular pin can be inserted into the anterior inferior iliac spine, which lies 3 cm inferior and 2 cm medial to the ASIS, and advanced along the supra-acetabular bone by angling the pin 30° caudal and 25° medial to the crestal plane.


Asunto(s)
Acetábulo/diagnóstico por imagen , Luxación de la Cadera/diagnóstico por imagen , Radiografía/métodos , Acetábulo/lesiones , Adulto , Análisis de Varianza , Femenino , Luxación de la Cadera/fisiopatología , Humanos , Masculino , Radiografía/instrumentación , Radiografía/estadística & datos numéricos , Tomografía Computarizada por Rayos X/métodos , Tomografía Computarizada por Rayos X/estadística & datos numéricos
3.
J Mech Behav Biomed Mater ; 108: 103833, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32469726

RESUMEN

The temporal muscle fascia (TMF) is a widely used graft material and of interest for computational simulations of the temporomandibular joint as well as computational and physical human head models in general. However, reliable biomechanical properties of the TMF are lacking to date. This study provides tensile data of 52 TMFs at an age range of 18 to 94 years. It further investigates, if acellular fascia scaffolds differ from native counterparts in their biomechanical behaviour. Native TMF has a median elastic modulus of 26.2 MPa (acellular: 24.5 MPa), an ultimate tensile strength of 2.9 MPa (acellular: 2.1 MPa), a maximum force of 12.6 N (acellular: 9.9 N) and a strain at failure of 14.1% (acellular: 14.8%). No significant difference was found regarding the properties of native and acellular samples. Elastic modulus and the ultimate tensile strength increased with age but only in the acellular group (p < 0.01). Decorin and fibronectin seemed to be washed out by the acellularization procedure. The absence of cells in acellular TMF samples is not of biomechanical relevance compared to the native state. Acellular TMF is a biomechanically promising scaffold material for graft purposes, which can be retrieved easily due to its superficial location.


Asunto(s)
Procedimientos de Cirugía Plástica , Músculo Temporal , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Módulo de Elasticidad , Fascia , Humanos , Persona de Mediana Edad , Resistencia a la Tracción , Adulto Joven
4.
Surg Radiol Anat ; 41(6): 607-611, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30937565

RESUMEN

PURPOSE: To describe the origin of the vessels supplying the anterior sub-axial cervical vertebrae (C3-C7) to further understand their potential influence on anterior bone loss after anterior cervical spinal surgery. METHOD: Cadaveric dissection was performed on ten adult human necks after latex perfusion of their subclavian, common carotid and vertebral arteries. The nutrient vessels of the sub-axial cervical spine were identified and traced to their origin. The course and distribution of these vessels and their nutrient foraminae are described. RESULTS: In all cases the anterior nutrient vessels were derived from the thyro-cervical trunk with branches that passed over the longus coli muscles forming a leash of vessels in the pre-vertebral fascia which subsequently extended in a frond-like pattern to pass onto the anterior aspect of vertebrae. The more cranial the cervical level the fewer the number of nutrient vessels and foraminae. The distribution of the foraminae on the anterior vertebral body followed the oblique supero-medial course of the nutrient vessels. CONCLUSION: Nutrient vessels perforate the cervical vertebrae on their anterior surface. These are derived from a leash of vessels that lie within the pre-vertebral fascia overlying the longus coli muscles. The origin of these vessels is the ascending cervical artery with a variable contribution from the transverse cervical artery.


Asunto(s)
Vértebras Cervicales/irrigación sanguínea , Arteria Vertebral/anatomía & histología , Anciano , Anciano de 80 o más Años , Cadáver , Humanos
5.
Z Orthop Unfall ; 155(1): 52-60, 2017 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-27716867

RESUMEN

Background: In total hip arthroplasty (THA), femoral head diameter has not been regarded as a key parameter which should be restored when reconstructing joint biomechanics and geometry. Apart from the controversial discussion on the advantages and disadvantages of using larger diameter heads, their higher cost is another important reason that they have only been used to a limited extent. The goal of this study was to analyse the price structure of prosthetic heads in comparison to other components used in THA. A large group of patients with hip endoprostheses were evaluated with respect to the implanted socket diameter and thus the theoretically attainable head diameter. Materials and Methods: The relative prices of various THA components (cups, inserts, stems and ball heads) distributed by two leading German manufacturers were determined and analysed. Special attention was paid to different sizes and varieties in a series of components. A large patient population treated with THA was evaluated with respect to the implanted cup diameter and therefore the theoretically attainable head diameter. Results: The pricing analysis of the THA components of two manufacturers showed identical prices for cups, inserts and stems in a series. In contrast to this, the prices for prosthetic heads with a diameter of 36-44 mm were 11-50 % higher than for 28 mm heads. Identical prices for larger heads were the exception. The distribution of the head diameter in 2719 THA cases showed significant differences between the actually implanted and the theoretically attainable heads. Conclusion: There are proven advantages in using larger diameter ball heads in THA and the remaining problems can be solved. It is therefore desirable to correct the current pricing practice of charging higher prices for larger components. Instead, identical prices should be charged for all head diameters in a series, as is currently established practice for all other THA components. Thus when reconstructing biomechanics and joint geometry in THA, it should be possible to recover not only leg length, femoral offset and antetorsion of the femoral neck, but also to approximately restore the diameter of the femoral head and thereby optimise the functional outcome.


Asunto(s)
Artroplastia de Reemplazo de Cadera/economía , Artroplastia de Reemplazo de Cadera/instrumentación , Análisis Costo-Beneficio/economía , Costos de la Atención en Salud/estadística & datos numéricos , Luxación de la Cadera/economía , Luxación de la Cadera/prevención & control , Prótesis de Cadera/economía , Simulación por Computador , Análisis Costo-Beneficio/métodos , Análisis de Falla de Equipo , Alemania/epidemiología , Prótesis de Cadera/clasificación , Prótesis de Cadera/estadística & datos numéricos , Humanos , Modelos Económicos , Diseño de Prótesis , Ajuste de Prótesis/economía , Reoperación/economía , Reoperación/estadística & datos numéricos
6.
Orthop Traumatol Surg Res ; 102(6): 723-8, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27478000

RESUMEN

BACKGROUND: The removal of well-fixed acetabular components following THA (total hip arthroplasty) is a difficult operation and could be accompanied by the loss of acetabular bone stock. The optimal method for fixation is still under debate. The aim of this pilot study was to compare the tear-out resistance and failure behavior between osseo-integrated and non-integrated screw cups. Furthermore, we examined whether there are differences in the properties mentioned between screw sockets and cemented polyethylene cups. HYPOTHESIS: Tear-out resistance and related mechanical work required for the tear-out of osseo-integrated screw sockets are higher than in non-integrated screw sockets. PATIENTS AND METHODS: Ten human coxal bones from six cadavers with osseo-integrated screw sockets (n=4), non-integrated (implanted post-mortem, n=3) screw sockets and cemented polyethylene cups (n=3) were used for tear-out testing. The parameters axial failure load and mechanical work for tear-out were introduced as measures for determining the stability of acetabular components following THA. RESULTS: The osseo-integrated screw sockets yielded slightly higher tear-out resistance (1.61±0.26kN) and related mechanical work compared to the non-integrated screw sockets (1.23±0.39kN, P=0.4). The cemented polyethylene cups yielded the lowest tear-out resistance with a failure load of 1.18±0.24kN. Compared to the screw cups implanted while alive, they also differ on a non-significant level (P=0.1). Osseous failure patterns differed especially for the screw sockets compared to the cemented polyethylene cups. DISCUSSION: Osseo-integration did not greatly influence the tear-out stability in cementless screw sockets following axial loading. Furthermore, the strength of the bone-implant-interface of cementless screw sockets appears to be similar to cemented polyethylene cups. However, given the high failure load, high mechanical load and because of the related bone failure patterns, removal should not be performed by means of tear-out but rather by osteotomes or other curved cutting devices to preserve the acetabular bone stock. LEVEL OF EVIDENCE: Level III, case-control-study.


Asunto(s)
Acetábulo , Tornillos Óseos , Prótesis de Cadera , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo de Cadera , Cementos para Huesos , Cadáver , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Polietileno , Falla de Prótesis , Estrés Mecánico
7.
Z Orthop Unfall ; 153(3): 299-305, 2015 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-26114561

RESUMEN

Juxtacortical osteosarcomas are a group of rare primary bone tumours. They differ from medullary osteosarcomas in their anatomic location (outside of the corticalis), low metastasis rate and better prognosis. The only evidence-based treatment of juxtacortical osteosarcomas is the wide surgical resection. In this technical report we will introduce a new surgical technique, including the subtotal resection of the tumour-bearing bone segment, defect reconstruction by means of an augmenting fixed-angle plate osteosynthesis and homologous cancellous bone graft. If necessary, a subsequent plastic coverage of the soft tissue defect was performed. The technique will be presented by means of three illustrated cases of young patients with juxtacortical osteosarcomas in the proximity of the knee joint. Following diagnostic confirmation by means of an incision biopsy and tumour staging, the three patients underwent this new surgical technique. In the postoperative follow-up and re-staging, two to seven years after surgery, all patients were under complete remission, had functionally restored knee joints (Karnofsky score 90 % or higher) and showed good aesthetic results. The surgical technique described may therefore be an adequate alternative to the complete resection of the tumour-bearing bone segment with prosthetic reconstruction and should be considered on the basis of the illustrated functional results in individual cases.


Asunto(s)
Neoplasias Óseas/cirugía , Placas Óseas , Trasplante Óseo/métodos , Fijación Interna de Fracturas/instrumentación , Fijación Interna de Fracturas/métodos , Osteosarcoma/cirugía , Adolescente , Neoplasias Óseas/diagnóstico por imagen , Terapia Combinada/instrumentación , Terapia Combinada/métodos , Femenino , Humanos , Masculino , Osteosarcoma/diagnóstico por imagen , Radiografía , Procedimientos de Cirugía Plástica/instrumentación , Procedimientos de Cirugía Plástica/métodos , Reoperación , Resultado del Tratamiento , Adulto Joven
8.
Orthopade ; 44(5): 381-91, 2015 May.
Artículo en Alemán | MEDLINE | ID: mdl-25869176

RESUMEN

BACKGROUND: Dislocation is a devastating complication after total hip arthroplasty (THA) and occurs in 2-5% of primary THA cases and 5-10% of revision THA cases. Assuming correct implantation, dislocation risk can be reduced primarily by capsular repair and the use of larger prosthetic heads. However, larger heads are also associated with risks like accelerated wear or implant loosening, which is why heads with a maximum diameter of 36 mm are currently standard in primary THA. In cases with high dislocation risk, the use of 40 mm and 44 mm heads should be considered. OBJECTIVES: This study aimed to quantify THA dislocation risk and retrospectively analyze the course of disease in high-risk patients treated with 40 mm or 44 mm femoral heads after primary or revision THA, concerning dislocation and other complications suffered. MATERIALS AND METHODS: All patients with increased THA dislocation risk, treated from 2009-2014, were evaluated regarding dislocations. The cases with installation of 40 mm or 44 mm prosthetic heads were classified using a self-developed 5-level risk score and retrospectively analyzed. RESULTS: During the observation period, 288 THA interventions with increased dislocation risk were performed. In 278 cases with ball diameters ≤ 36 mm the dislocation rate was 15.1% (n=42). In 10 high dislocation-risk cases (3A to 4B according to recommended scoring system), 40 mm and 44 mm heads were used. After a 22.8 month mean follow-up, no THA dislocations were reported. CONCLUSION: Our results with 40 and 44 mm heads and the existing literature confirm much higher joint stability and, thus, significantly reduced dislocation risk with larger prosthetic heads in THA. Their use is, therefore, justified in high-risk patients and should be considered in future THA.


Asunto(s)
Artroplastia de Reemplazo de Cadera/instrumentación , Artroplastia de Reemplazo de Cadera/estadística & datos numéricos , Luxación de la Cadera/epidemiología , Prótesis de Cadera/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Anciano , Anciano de 80 o más Años , Análisis de Falla de Equipo , Femenino , Alemania/epidemiología , Luxación de la Cadera/prevención & control , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/prevención & control , Diseño de Prótesis , Medición de Riesgo
9.
Nervenarzt ; 85(12): 1561-8, 2014 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-25431126

RESUMEN

BACKGROUND: Deep brain stimulation (DBS) has become a reliable method in the treatment of movement disorders, e.g. idiopathic Parkinson's disease (IPD) and is technically based on stereotaxy. The Starfix® platform is a new type of stereotactic frame that allows an individualized and patient-optimized therapeutic regimen in IPD. OBJECTIVES: The aim of this study was to retrospectively compare the outcomes of IPD patients who underwent surgery with the use of conventional stereotactic frames (31 patients) to those who underwent implantation of DBS with the use of Starfix® frames (29 patients). MATERIAL AND METHODS: Surgery time, the unified Parkinson's disease rating scale III (UPDRS/III) score, L-dopa and L-dopa equivalent doses (LED) were compared prior to surgery as well as 4 weeks, 12 weeks, 6 months and 1 year postoperatively. RESULTS: The IPD-related symptoms improved significantly in both groups with respect to the UPDRS III score (conventional 69.6% vs. 72.4% Starfix®). After surgery significant reductions of L-dopa and LED were seen in both groups. Inherent advantages of the Starfix® platform included simultaneous positioning of the stimulating electrodes and a significant reduction in surgical time. CONCLUSION: In summary, both stereotactic procedures are reliable and safe procedures for the placement of stimulating electrodes as well as the stimulation effect achieved. The logistical uncoupling of presurgical planning from surgical therapy emphasizes the benefits of the individualized stereotactic procedure.


Asunto(s)
Estimulación Encefálica Profunda/instrumentación , Estimulación Encefálica Profunda/métodos , Electrodos Implantados , Trastornos del Movimiento/terapia , Enfermedad de Parkinson/terapia , Implantación de Prótesis/instrumentación , Técnicas Estereotáxicas/instrumentación , Adulto , Anciano , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Trastornos del Movimiento/etiología , Enfermedad de Parkinson/complicaciones , Implantación de Prótesis/métodos , Resultado del Tratamiento
10.
Z Orthop Unfall ; 152(2): 130-43, 2014 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-24760453

RESUMEN

BACKGROUND: Dislocation is the second most frequently encountered complication in primary total hip arthroplasty (THA) and occurs more commonly in the early postoperative rehabilitation phase. Sir Charnley recommended the "avoidance of resection of the capsule" and emphasised its contribution to hip joint stability in THA. Several authors, however, doubted its significance and considered resection of the capsule to be essential. Since 2002, some surgeons increasingly adopted a modified, less invasive technique of THA via Bauer approach, including the preservation and repair of the hip joint capsule with focus on maintaining its acetabular origin. Another group of surgeons applied the traditional technique including the resection of the joint capsule via an anterolateral approach. In this case-control study we investigated whether the dislocation rate can be reduced through joint capsule reconstruction and whether any negative impact on patient satisfaction, functional results or revision rate is observed. MATERIAL AND METHODS: All cases of primary THA performed in our institution in a timeframe between 2002 and 2009 were included with the only exceptions of resurfacing arthroplasty, dual mobility and tumour hip replacements. Joint capsule repair cases were gathered in the study group (SG), capsule resection cases in the control group (CG). Additional patient-related data were taken from the anaesthesia records. The WOMAC score and a questionnaire focusing on detection of dislocations and revision surgeries was sent out for each case. Further targeted research was conducted that included requesting records and reports from external hospitals. In the case of non-responding patients, all available data (operating room documentation, electronic files, archive, X-rays) were reviewed for incidents of dislocation and revision surgery. Groupings and classifications were exclusively performed by senior surgeons. SG and CG were compared regarding epidemiologic, implant-associated and surgery-specific data. Statistical evaluations were performed using the Chi-squared test and the Mann-Whitney U test. RESULTS: 1972 cases of primary THA were included: 992 in the SG and 980 in the CG. The follow-up rates were 92.7 % in the SG and 76.4 % in the CG, the mean follow-up times 33.5 months and 73.4 months, respectively, with a follow-up of at least 12 months in all cases. In the SG, the dislocation rate was 0.3 % (n = 3) and thus significantly lower than the 2.55 % in the CG (n = 25, p < 0.001). Both the WOMAC score (SG: 1.46 ± 1.73; CG: 1.53 ± 1.80; p > 0.05) and the revision rate (SG: 5.24 %; CG: 6.84 %; p = 0.139) showed no significant differences. CONCLUSION: Preservation and repair of the hip joint capsule causes an 88-%-reduction of the dislocation rate in primary THA in this large series including 1972 cases, operated via the Bauer or the anterolateral approach. Several authors reported comparable results after THA using similar techniques of soft tissue and capsular repair through the posterior or posterolateral approach. Sparing and reconstructing the hip joint capsule therefore seems to reduce the dislocation rate after primary THA by one order of magnitude regardless of the surgical approach and, especially, if the acetabular origin is preserved. Capsule-related specific complications such as an increased revision rate, malfunction or pain were neither recorded in our study nor by others. Thus, careful preservation and reconstruction of the hip joint capsule may be expressly recommended in primary THA.


Asunto(s)
Artroplastia de Reemplazo de Cadera/estadística & datos numéricos , Luxación de la Cadera/epidemiología , Luxación de la Cadera/prevención & control , Cápsula Articular/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Adulto , Anciano , Femenino , Alemania/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Recuperación de la Función , Estudios Retrospectivos , Medición de Riesgo , Resultado del Tratamiento
11.
J Chem Phys ; 122(20): 204319, 2005 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-15945736

RESUMEN

The formation of negative ions in molecular beams of ethylene sulfite (ES, alternately called glycol sulfite or ethylene glycol, C(2)H(4)SO(3)) molecules has been studied using both Rydberg electron transfer (RET) and free electron attachment methods. RET experiments with jet-cooled ES show an unexpected broad profile of anion formation as a function of the effective quantum number (n(*)) of the excited rubidium atoms, with peaks at n(max)(*) approximately 13.5 and 16.8. The peak at n(max)(*) approximately 16.8 corresponds to an expected dipole-bound anion with an electron binding energy of 8.5 meV. It is speculated that the peak at n(max)(*) approximately 13.5 derives from the formation of a distorted C(2)H(4)SO(3)(-) ion. We suggest that quasifree electron attachment promotes the breaking of one ring bond giving a long-lived acyclic anion and term this process incomplete dissociative electron attachment. Theoretical calculations of plausible ionic structures are presented and discussed. Electron beam studies of ES reveal the presence of multiple dissociative attachment channels, with the dominant fragment, SO(2)(-), peaking at 1.3 eV and much weaker signals due to SO(3)(-), SO(-), and (ES-H)(-) peaking at 1.5, 1.7, and 0.9 eV, respectively. All of these products appear to originate from a broad temporary negative ion resonance centered at approximately 1.4 eV.

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