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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Tendons with dissimilar functions have different structural and material properties

Batson, Emma Louise January 2002 (has links)
No description available.
2

Avaliação da terapia por laser de arsenito e gálio em tendinite de cavalos Puro Sangue Inglês de corrida / Evaluation of Gallium Arsenide Laser for treatment of equine tendinitis

Mikail, Solange Corrêa 16 July 2008 (has links)
Para avaliar a eficácia do laser de arsenito de gálio em acelerar a cicatrização tendínea em cavalos PSI de corrida com lesão no tendão flexor digital superficial, foram realizados dois experimentos, primeiro (E1) com 14 casos clínicos onde as lesões foram decorrentes do esporte em um dos membros torácicos, o segundo (E2) com cinco casos experimentais, onde as lesões foram induzidas com colagenase em ambos os membros torácicos. No E1, após a detecção da lesão no tendão flexor digital superficial por exame ultra-sonográfico, todos os animais receberam antiinflamatório não esteróide associado à dimetilsulfóxido por via intravascular, crioterapia no local da lesão, e caminharam ao passo duas vezes ao dia por 15 minutos durante os 30 dias de acompanhamento. Os membros tratados pertenceram a onze animais que receberam uma sessão diária de laser de arsenito de gálio na dose de 20 J/cm2, realizadas durante 10 dias consecutivos, após término do antiinflamatório e da crioterapia. Os membros controle pertenceram a três animais, os quais não foram tratados com laser. No E2, após identificação das lesões, foram escolhidos aleatoriamente um membro torácico controle e outro a ser tratado por laser em cada animal. Da mesma forma, estes animais foram mantidos a passo e receberam o mesmo protocolo de laserterapia que os membros tratados do E1. Todos os membros foram avaliados através de exames ultra-sonográficos, utilizando-se como parâmetros o paralelismo das fibras tendíneas em corte longitudinal; a ecogenicidade, a área do tendão, a área da lesão e a porcentagem de ocupação da lesão em corte transversal. No E1, os membros controle não apresentaram diferença significativa (P>0,05) nos parâmetros avaliados entre os dias 0 e 30. Nos membros tratados, a área do tendão também não apresentou diferença significativa (P>0,05) entre os dias analisados, porém houve diminuição muito significativa nos escores de ecogenicidade e paralelismo (P<0,001), assim como diminuição no tamanho da lesão (P<0,05) e na porcentagem de ocupação da lesão (P<0,05). No E2 também não houve diferença significativa entre os dias em todos os critérios avaliados nos membros controles (P>0,05). Nos membros tratados a ecogenicidade, o paralelismo e o tamanho do tendão, não sofreram alterações significativas (P>0,05) entre os dias avaliados, porém o tamanho da lesão (P<0,05) e a porcentagem de ocupação da lesão (P<0,01) apresentaram diminuição significativa. O laser de arsenito de gálio na dose de 20 J/cm2 mostrou-se eficaz em acelerar a reparação da lesão tendínea nos membros tratados em relação aos membros controle, tanto no grupo de casos clínicos quanto no grupo experimental, quando comparados aos 30 dias do aparecimento da lesão. Esses resultados sugerem a participação positiva do laser de arsenito de gálio nos resultados e a validação do mesmo no tratamento da tendinite do flexor digital superficial de cavalos Puro Sangue Inglês de corrida. / This study conducted two trials to evaluate the efficacy of Gallium Arsenide Laser in the speed of the healing process of superficial digital flexor tendon (SDFT) lesions in thoroughbred horses. One trial group (T1) comprises 14 horses with lesions, which resulted from the sport, in the SDFT in one of the front limbs. The other trial group (T2) was formed by five horses that had lesions induced in both front limbs by collagenase injection. In the T1, after the detection of the lesion in the SDFT by ultrasonography all horses were treated by intravenous injection, once a day, over five days, with an association of two AINS: phenylbutazone and dimethylsulfoxide. Cryotherapy was also applied on the affected tendon (three times a day over five days) and the horses were kept in stalls and allowed controlled exercise (hand-walked twice daily for 15 minutes) during the 30 days of the study. The treated limbs belong to 11 horses that received laser sessions once a day for ten days at a dosage of 20J/cm2. These sessions started after the AINS association and cryotherapy. The control limbs belong to the other three horses that received the same treatment, except by the laser sessions. In the T2, after the detection of the lesion, a limb from each horse was randomly chosen to be the control limb and the other limb was treated by laser. These horses were also kept in stall under controlled exercise and the treated limb was under the same laser protocol that T1. All horses were evaluated by two ultrasonographic exams with a 30-day interval. The parameters evaluated were: the fiber alignment, the echogenicity, the tendon area, the lesion area and the proportion of the cross sectional area involved. In the T1, the control limbs showed no significant difference (p>0,05) in the echogenicity, the fiber alignment, the tendon area, the lesion area or the proportion of the cross sectional area involved, between the day 0 and 30. The treated limb, didn´t show any significant difference of the tendon area, but showed a significant difference on the echogenicity (P<0,001), the fiber alignment (P<0,001), the lesion area (P<0,05) and the proportion of the cross sectional area involved (P<0,05). In the T2, only one limb received the laser treatment, the other limb acted as a control. The control limbs showed no significant difference (P>0,05) in the echogenicity, the fiber alignment, the tendon area, the lesion area and the proportion of the cross sectional area involved between the day 0 and 30. The treated limbs showed no significant difference (P>0,05) in the echogenicity, the fiber alignment and the tendon area, but showed significant difference in the lesion area (P<0,05) and the proportion of the cross sectional area involved (P<0,01). The treatment dose of 20J/cm2 of gallium arsenide laser was efficient in speeding the healing process of SDFT lesions of the laser treated limbs in both groups (T1 and T2), when compared with the control limbs, at 30 days of the onset of the lesion. The group which lesions occurred due to the sport (T1) had a better response to the treatment than the group which lesions were induced by collagenasis (T2). The limbs treated by laser showed a positive response which validates the use of the Gallium Arsenide laser for the treatment of tendinitis in the Superficial Digital Flexor in race horses.
3

Avaliação da terapia por laser de arsenito e gálio em tendinite de cavalos Puro Sangue Inglês de corrida / Evaluation of Gallium Arsenide Laser for treatment of equine tendinitis

Solange Corrêa Mikail 16 July 2008 (has links)
Para avaliar a eficácia do laser de arsenito de gálio em acelerar a cicatrização tendínea em cavalos PSI de corrida com lesão no tendão flexor digital superficial, foram realizados dois experimentos, primeiro (E1) com 14 casos clínicos onde as lesões foram decorrentes do esporte em um dos membros torácicos, o segundo (E2) com cinco casos experimentais, onde as lesões foram induzidas com colagenase em ambos os membros torácicos. No E1, após a detecção da lesão no tendão flexor digital superficial por exame ultra-sonográfico, todos os animais receberam antiinflamatório não esteróide associado à dimetilsulfóxido por via intravascular, crioterapia no local da lesão, e caminharam ao passo duas vezes ao dia por 15 minutos durante os 30 dias de acompanhamento. Os membros tratados pertenceram a onze animais que receberam uma sessão diária de laser de arsenito de gálio na dose de 20 J/cm2, realizadas durante 10 dias consecutivos, após término do antiinflamatório e da crioterapia. Os membros controle pertenceram a três animais, os quais não foram tratados com laser. No E2, após identificação das lesões, foram escolhidos aleatoriamente um membro torácico controle e outro a ser tratado por laser em cada animal. Da mesma forma, estes animais foram mantidos a passo e receberam o mesmo protocolo de laserterapia que os membros tratados do E1. Todos os membros foram avaliados através de exames ultra-sonográficos, utilizando-se como parâmetros o paralelismo das fibras tendíneas em corte longitudinal; a ecogenicidade, a área do tendão, a área da lesão e a porcentagem de ocupação da lesão em corte transversal. No E1, os membros controle não apresentaram diferença significativa (P>0,05) nos parâmetros avaliados entre os dias 0 e 30. Nos membros tratados, a área do tendão também não apresentou diferença significativa (P>0,05) entre os dias analisados, porém houve diminuição muito significativa nos escores de ecogenicidade e paralelismo (P<0,001), assim como diminuição no tamanho da lesão (P<0,05) e na porcentagem de ocupação da lesão (P<0,05). No E2 também não houve diferença significativa entre os dias em todos os critérios avaliados nos membros controles (P>0,05). Nos membros tratados a ecogenicidade, o paralelismo e o tamanho do tendão, não sofreram alterações significativas (P>0,05) entre os dias avaliados, porém o tamanho da lesão (P<0,05) e a porcentagem de ocupação da lesão (P<0,01) apresentaram diminuição significativa. O laser de arsenito de gálio na dose de 20 J/cm2 mostrou-se eficaz em acelerar a reparação da lesão tendínea nos membros tratados em relação aos membros controle, tanto no grupo de casos clínicos quanto no grupo experimental, quando comparados aos 30 dias do aparecimento da lesão. Esses resultados sugerem a participação positiva do laser de arsenito de gálio nos resultados e a validação do mesmo no tratamento da tendinite do flexor digital superficial de cavalos Puro Sangue Inglês de corrida. / This study conducted two trials to evaluate the efficacy of Gallium Arsenide Laser in the speed of the healing process of superficial digital flexor tendon (SDFT) lesions in thoroughbred horses. One trial group (T1) comprises 14 horses with lesions, which resulted from the sport, in the SDFT in one of the front limbs. The other trial group (T2) was formed by five horses that had lesions induced in both front limbs by collagenase injection. In the T1, after the detection of the lesion in the SDFT by ultrasonography all horses were treated by intravenous injection, once a day, over five days, with an association of two AINS: phenylbutazone and dimethylsulfoxide. Cryotherapy was also applied on the affected tendon (three times a day over five days) and the horses were kept in stalls and allowed controlled exercise (hand-walked twice daily for 15 minutes) during the 30 days of the study. The treated limbs belong to 11 horses that received laser sessions once a day for ten days at a dosage of 20J/cm2. These sessions started after the AINS association and cryotherapy. The control limbs belong to the other three horses that received the same treatment, except by the laser sessions. In the T2, after the detection of the lesion, a limb from each horse was randomly chosen to be the control limb and the other limb was treated by laser. These horses were also kept in stall under controlled exercise and the treated limb was under the same laser protocol that T1. All horses were evaluated by two ultrasonographic exams with a 30-day interval. The parameters evaluated were: the fiber alignment, the echogenicity, the tendon area, the lesion area and the proportion of the cross sectional area involved. In the T1, the control limbs showed no significant difference (p>0,05) in the echogenicity, the fiber alignment, the tendon area, the lesion area or the proportion of the cross sectional area involved, between the day 0 and 30. The treated limb, didn´t show any significant difference of the tendon area, but showed a significant difference on the echogenicity (P<0,001), the fiber alignment (P<0,001), the lesion area (P<0,05) and the proportion of the cross sectional area involved (P<0,05). In the T2, only one limb received the laser treatment, the other limb acted as a control. The control limbs showed no significant difference (P>0,05) in the echogenicity, the fiber alignment, the tendon area, the lesion area and the proportion of the cross sectional area involved between the day 0 and 30. The treated limbs showed no significant difference (P>0,05) in the echogenicity, the fiber alignment and the tendon area, but showed significant difference in the lesion area (P<0,05) and the proportion of the cross sectional area involved (P<0,01). The treatment dose of 20J/cm2 of gallium arsenide laser was efficient in speeding the healing process of SDFT lesions of the laser treated limbs in both groups (T1 and T2), when compared with the control limbs, at 30 days of the onset of the lesion. The group which lesions occurred due to the sport (T1) had a better response to the treatment than the group which lesions were induced by collagenasis (T2). The limbs treated by laser showed a positive response which validates the use of the Gallium Arsenide laser for the treatment of tendinitis in the Superficial Digital Flexor in race horses.
4

Cyclic tensile tests of Shetland pony superficial digital flexor tendons (SDFTs) with an optimized cryo-clamp combined with biplanar high-speed fluoroscopy

Wagner, Franziska Carolin, Reese, Sven, Gerlach, Kerstin, Böttcher, Peter, Mülling, Christoph K. W. 05 March 2022 (has links)
Background: Long-term cyclic tensile testing with equine palmar/plantar tendons have not yet been performed due to problems in fixing equine tendons securely and loading them cyclically. It is well established that the biomechanical response of tendons varies during cyclic loading over time. The aim of this study was to develop a clamping device that enables repetitive cyclic tensile testing of equine superficial digital flexor tendon for at least 60 loading cycles and for 5 min. Results: A novel cryo-clamp was developed and built. Healthy and collagenase-treated pony SDFTs were mounted in the custom-made cryo-clamp for the proximal tendon end and a special clamping device for the short pastern bone (os coronale). Simultaneously with tensile testing, we used a biplanar high-speed fluoroscopy system (FluoKin) to track tendon movement. The FluoKin system was additionally validated in precision measurements. During the cyclic tensile tests of the SDFTs, the average maximal force measured was 325 N and 953 N for a length variation of 2 and 4 % respectively. The resulting stress averaged 16 MPa and 48 MPa respectively, while the modulus of elasticity was 828 MPa and 1212 MPa respectively. Length variation of the metacarpal region was, on average, 4.87 % higher after incubation with collagenase. The precision of the FluoKin tracking was 0.0377 mm, defined as the standard deviation of pairwise intermarker distances embedded in rigid bodies. The systems accuracy was 0.0287 mm, which is the difference between the machined and mean measured distance. Conclusion: In this study, a good performing clamping technique for equine tendons under repetitive cyclic loading conditions is described. The presented cryo-clamps were tested up to 50 min duration and up to the machine maximal capacity of 10 kN. With the possibility of repetitive loading a stabilization of the time-force-curve and changes of hysteresis and creep became obvious after a dozen cycles, which underlines the necessity of repetitive cyclical testing. Furthermore, biplanar high-speed fluoroscopy seems an appropriate and highly precise measurement tool for analysis of tendon behaviour under repetitive load in equine SDFTs.
5

Early Cellular Influence of BMP12, Compared to BMP2, on Equine Superficial Digital Flexor Tenocytes and Bone Marrow Derived Mesenchymal Stem Cells in Vitro

Murray, Shannon J. 03 September 2009 (has links)
No description available.
6

Fluoreszenzkinematografische Untersuchung zur Sehnendehnbarkeit an der equinen oberflächlichen Beugesehne

Wagner, Franziska C. 04 February 2022 (has links)
Einleitung: Die oberflächliche Beugesehne (OBS) ist die am häufigsten verletzte Struktur des Bewegungsapparates von Pferden. Verletzungen der OBS verursachen ökonomische Einbußen im Pferdesport, sind unter Tierschutzaspekten hochrelevant und sind gekennzeichnet von langen Rekonvaleszenzzeiten von 9--18 Monaten und einer Wiederverletzungsrate von bis zu 80 %. Um Sehnenverletzungen, deren Heilung und den Therapieerfolg zu detektieren, bedarf es grundlegender Kenntnisse der Sehnenbiomechanik. Zur Anwendung kommende Messmethoden sollten idealerweise hochpräzise, minimalinvasiv und über einen längeren Zeitraum einsetzbar sein. Bislang etablierte Methoden genügen diesen Ansprüchen nur teilweise. Daher soll biplanare Hochfrequenz-Fluoreszenz-Kinematografie (FluoKin) als aktueller Goldstandard für Bewegungsstudien auf ihren Einsatz an equinen Sehnengewebe geprüft werden. Ziele der Untersuchungen waren es daher, 1) die Messgenauigkeit von FluoKin zu bestimmen und hinsichtlich Dehnbarkeitsmessungen equiner OBS zu evaluieren, 2) eine Technik zur Nutzung von FluoKin (3D-Röntgenmethode) zu finden, um die Bewegung eines Weichteilgewebes im Röntgenvideo zu visualisieren, 3) diese Methodik in zyklischen Zugprüfversuchen mit gesunden und Kollagenase-geschädigten OBS ex vivo zu prüfen und dafür eine geeignete Haltevorrichtung für die Sehnen zu entwickeln, 4) in einem Pilotversuch die Technik in vivo zu übertragen und in wiederkehrenden Messserien die Dehnung von gesundem, verletztem und heilendem Sehnengewebe zu messen. Tiere, Material und Methoden: Die Präzisionsmessungen wurden mit einem maßgefertigten Testplättchen und einer gefrorenen distalen Vordergliedmaße (VGlm) jeweils statisch (1976 und 5473 Bilder) und in Bewegung (2816 und 5021 Bilder) durchgeführt. Die Sehnenhaltevorrichtung inkl. Kryo-Klemme wurde neben dem Einsatz in der Ex-vivo-Studie zusätzlich Langzeittests (bis 50 min) und Rupturversuchen bis 10 kN (Maschinenlimit) unterzogen. Im Rahmen der Ex-vivo-Zugprüfversuche wurden 13 OBS von VGlm in Schritt (2 %)- und Trab (4 %)-simulierender Dehnung zyklisch getestet. Vier weitere Proben wurden mit Kollagenase inkubiert und inkl. einer Kontrollgruppe (n=4) bei 6 % getestet. Die biomechanischen Kenngrößen wurden von der Zugprüfmaschine erfasst und anhand der Bewegung von implantierten, röntgendichten Markern in zeitgleich aufgenommenen FluoKin-Videos errechnet. In der In-vivo-Langzeitstudie (37 Wochen) wurde in vier FluoKin-Messungen das Dehnverhalten der OBS beider VGlm eines Shetland Ponys in Schritt und Trab ermittelt. Vor der zweiten FluoKin-Messung wurde im mittleren metakarpalen Segment einer OBS eine Sehnenläsion mit Kollagenase induziert, deren Heilungsverlauf verfolgt wurde. Die Ergebnisbeschreibung erfolgte sowohl deskriptiv als auch bei entsprechender Stichprobengröße mit t-Tests (p<0,05). Ergebnisse: In Präzisionsmessungen wurden sowohl die Messgenauigkeit der FluoKin-Anlage (max. Exaktheit von 0,0287 mm ± 0,0377 mm), als auch die zu erwartende Standardabweichung in der studienrelevanten Region (Os metacarpale III, OBS) ermittelt. Im Rahmen der Ex-vivo-Zugprüfversuche wurde eine Haltevorrichtung inkl. Kryo-Klemme für equine OBS entwickelt, welche Probleme herkömmlicher Einspanntechniken zuverlässig löst. Erstmals konnten biomechanische Kenngrößen für die OBS von Shetland Ponys ermittelt werden. Im Mittel konnten abhängig von der Dehnungsrate (simulierter Schritt und Trab) eine Maximalkraft von 325 bzw. 953 N, eine Zugfestigkeit von 1649 bzw. 4820 N/cm² und ein Elastizitätsmodul von 828 bzw. 1212 MPa verzeichnet werden. Nach Inkubation mit Kollagenase stieg die Längenänderung im Mittel um 4,87 %. In vivo konnte die Dehnungszunahme der geschädigten OBS im Schritt bestätigt werden (2,86 % auf 3,38 %); im Trab zeigte sich hingegen ein Abfall (6,78 % auf 5,96 %). Schlussfolgerungen: FluoKin wurde als hochpräzise und minimalinvasive Messtechnik zur Ermittlung der Sehnendehnung equiner OBS ex vivo und erstmals in vivo erfolgreich eingesetzt. Dank der neu entwickelten Haltevorrichtung inkl. Kryo-Klemme konnten langandauernde Ex-vivo-Zugprüfversuche durchgeführt werden. Hierbei zeigten sich Änderungen des Dehnverhaltens der OBS (Konditionierung, Hysterese, Kriechphänomen), was die Notwendigkeit solcher Versuche für die Beschreibung des biomechanischen Verhaltens von Sehnen verdeutlicht. Der In-vivo-Pilotversuch unterstreicht die Bedeutung von FluoKin für innovatives und hochpräzises Monitoring von Sehnenläsionen in Langzeitstudien.:1 Einleitung 2 Literaturübersicht 2.1 Sehnengewebe 2.1.1 Histologischer und molekularer Aufbau 2.1.2 Biomechanik 2.1.3 Einflüsse auf die Sehnenstruktur und -zusammensetzung 2.2 Tendinopathien der oberflächlichen Beugesehne 2.2.1 Ätiologie 2.2.2 Heilung 2.3 Möglichkeiten zur Bestimmung der Sehnendehnbarkeit 2.3.1 Ex-vivo-Zugprüfversuche mit Sehnen 2.3.2 In-vivo-Ermittlung der Sehnendehnbarkeit 2.4 Zentrale Fragestellungen 3 Publikation 1 Zyklische Zugprüfversuche mit einer neuartigen Kryo-Klemme an oberflächlichen Beugesehnen von Shetland Ponys kombiniert mit biplanarer Hochfrequenz-Fluoreszenz-Kinematografie 4 Publikation 2 Biplanare Hochfrequenz-Fluoreszenz-Kinematografie an der oberflächlichen Beugesehne eines Shetland Ponys – eine In-vivo-Pilotstudie 5 Diskussion 5.1 Diskussion von Material und Methoden 5.1.1 Ermittlung der Messgenauigkeit von FluoKin 5.1.2 Verwendetes Tiermaterial 5.1.3 Implantationstechnik für Sehnenmarker 5.1.4 Aufbau der Ex-vivo-Zugprüfversuche 5.2 Bestimmung der Sehnendehnbarkeit mit FluoKin 5.2.1 Sehnendehnung ex vivo und in vivo in nativem Sehnengewebe 5.2.2 Sehnendehnung ex vivo und in vivo in Kollagenase-geschädigtem Sehnengewebe 5.3 Schlussfolgerungen und Ausblick 5.3.1 Praktische und klinische Relevanz 5.3.2 Fazit und Perspektiven 6 Zusammenfassung 7 Summary 8 Literaturverzeichnis 9 Anhang 9.1 Bauplan des Messplättchens zur Genauigkeitsbestimmung von FluoKin 9.2 Baupläne der Einspanntechnik für Zugprüfversuche mit equinen OBS 9.2.1 Kronbeinhalterung 9.2.2 Kryo-Klemmen 9.3 Genauigkeit von biplanaren Fluoroskopie-Systemen in Abhängigkeit des Versuchsaufbaus 9.4 Lagerungseinflüsse auf biomechanische Eigenschaften von Sehnengewebe 9.5 Vorträge und Präsentationen während der Doktorarbeitszeit / Introduction: The superficial digital flexor tendon (SDFT) is the most frequently injured structure of the musculoskeletal system of horses. Injuries of the SDFT are relevant under animal welfare aspects, cause substantial economic losses in equestrian sport and are associated by long convalescence times of 9 to 18 months and a re-injury rate of up to 80 %. In order to detect tendon injuries, improve their healing and the success of therapy, fundamental knowledge of tendon biomechanics is required. The measurement methods to be used should ideally be highly precise, minimally invasive and applicable over a long period of time. So far, established methods only partially meet these requirements. Therefore, biplanar high-speed fluoroscopic kinematography (FluoKin) as the current gold standard for movement studies will be tested for its use on equine tendon tissue Aims of the study were therefore 1) to determine the measurement accuracy and precision of FluoKin and to evaluate it with regard to measurements on the equine SDFT, 2) to find a technique for using FluoKin (a 3D X-ray method) for visualizing the movement of a soft tissue in X-ray video, 3) to test this methodology in cyclic tensile tests with healthy and collagenase-incubated SDFT ex vivo and to develop a suitable holding device for the tendons in the testing machine, 4) to transfer the technique in an in vivo pilot study on a pony and to measure the elongation of healthy, injured and healing tendon tissue in measurement series. Materials and Methods: Precision measurements were performed with a custom-made test sheet and a frozen distal forelimb static (1976 and 5473 frames) and in motion (2816 and 5021 frames) resp. The tendon holding device with a cryo-clamp was subjected to long-term cyclic tests (up to 50 min) and rupture tests up to 10 kN (machine limit) in addition to its use in the ex vivo study. As part of the ex vivo tensile testing, 13 SDFT of forelimbs were cyclically tested in walk (2 % strain) and trot (4 % strain) simulated elongation. Four additional specimens were incubated with collagenase and tested including a control group (n=4) at 6 % strain. Biomechanical parameters were recorded by the testing machine and calculated from the movement of implanted radiopaque markers in simultaneously recorded FluoKin videos. In the in vivo long-term study (37 weeks) the strain behaviour of the SDFT of both forelimbs of a Shetland pony at walk and trot were determined in four FluoKin measurements. Before the second FluoKin measurement, a tendon lesion was induced with collagenase in the mid-metacarpal segment of one SDFT, and its healing process was monitored. The description of the results was done both descriptively and, with an appropriate sample size, with t-tests (p<0.05). Results: Measurements to assess the precision of both the FluoKin system (max. accuracy of 0.0287 mm ± 0.0377 mm) and the standard deviation to be expected in the region relevant to the study (Os metacarpale III, SDFT). For the ex vivo tensile tests, a holding device with a cryo-clamp for equine SDFT was developed that reliably solved problems of conventional clamping techniques. For the first time, biomechanical parameters for the SDFT of Shetland ponies could be determined. On average, depending on the strain rate (simulated walk and trot), a maximum force of 325 N and 953 N resp., a tensile strength of 1649 N/cm² and 4820 N/cm² resp. and a modulus of elasticity of 828 MPa and 1212 MPa resp. was recorded. After incubation with collagenase, the change in length increased by an average of 4.87 %. In vivo, this increased elongation of the collagenase-injured SDFT could be confirmed at walk (2.86 % to 3.38 %); in contrast, a decrease in strain was observed at trot (6.78 % to 5.96 %). Conclusions: FluoKin was successfully used as a highly precise and minimally invasive measurement technique to determine the tendon strain of equine SDFT ex vivo and for the first time also in vivo. Thanks to the newly developed holding device with a cryo-clamp, long-term ex vivo tensile tests could be carried out and changes in the strain behaviour of the SDFT became apparent (conditioning, hysteresis, creep). This shows the necessity of such tests for the description of the biomechanical behaviour of tendons. The in vivo pilot study underlines the importance of FluoKin for innovative and highly accurate monitoring of tendon lesions in long-term studies.:1 Einleitung 2 Literaturübersicht 2.1 Sehnengewebe 2.1.1 Histologischer und molekularer Aufbau 2.1.2 Biomechanik 2.1.3 Einflüsse auf die Sehnenstruktur und -zusammensetzung 2.2 Tendinopathien der oberflächlichen Beugesehne 2.2.1 Ätiologie 2.2.2 Heilung 2.3 Möglichkeiten zur Bestimmung der Sehnendehnbarkeit 2.3.1 Ex-vivo-Zugprüfversuche mit Sehnen 2.3.2 In-vivo-Ermittlung der Sehnendehnbarkeit 2.4 Zentrale Fragestellungen 3 Publikation 1 Zyklische Zugprüfversuche mit einer neuartigen Kryo-Klemme an oberflächlichen Beugesehnen von Shetland Ponys kombiniert mit biplanarer Hochfrequenz-Fluoreszenz-Kinematografie 4 Publikation 2 Biplanare Hochfrequenz-Fluoreszenz-Kinematografie an der oberflächlichen Beugesehne eines Shetland Ponys – eine In-vivo-Pilotstudie 5 Diskussion 5.1 Diskussion von Material und Methoden 5.1.1 Ermittlung der Messgenauigkeit von FluoKin 5.1.2 Verwendetes Tiermaterial 5.1.3 Implantationstechnik für Sehnenmarker 5.1.4 Aufbau der Ex-vivo-Zugprüfversuche 5.2 Bestimmung der Sehnendehnbarkeit mit FluoKin 5.2.1 Sehnendehnung ex vivo und in vivo in nativem Sehnengewebe 5.2.2 Sehnendehnung ex vivo und in vivo in Kollagenase-geschädigtem Sehnengewebe 5.3 Schlussfolgerungen und Ausblick 5.3.1 Praktische und klinische Relevanz 5.3.2 Fazit und Perspektiven 6 Zusammenfassung 7 Summary 8 Literaturverzeichnis 9 Anhang 9.1 Bauplan des Messplättchens zur Genauigkeitsbestimmung von FluoKin 9.2 Baupläne der Einspanntechnik für Zugprüfversuche mit equinen OBS 9.2.1 Kronbeinhalterung 9.2.2 Kryo-Klemmen 9.3 Genauigkeit von biplanaren Fluoroskopie-Systemen in Abhängigkeit des Versuchsaufbaus 9.4 Lagerungseinflüsse auf biomechanische Eigenschaften von Sehnengewebe 9.5 Vorträge und Präsentationen während der Doktorarbeitszeit

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