The following report has been prepared based upon an assignment given by the company, Ortopedic Care Scandinavia AB. The paper is an exam on basic level, 15 credit points at higher level education within product development. Ortopedic Care Scandinavia AB is working with product development of medical technology products. What makes the corporate unique is the fact that the development is based upon problems encountered by surgeons in their daily work. Suggestions for improvement in technology are given directly by the end users. This paper is based upon such problems. Product development was made on the medical instrument called, suture passer. The instrument is used in endoscopic surgery of the rotator cuff. The cuff is a group of four muscles (and their respective tendons) that stabilize the shoulder. In case of an accident, mostly sport related, these muscles can loosen from the bone. In surgery a suture passer is then used to penetrate the injured tendon with a needle with an attached suture. The passer creates a loop of suture that can be used to attach the damaged tendon. The report is based upon the following problem formulations: The needle has an inconvenient edge that can damage the muscle. The strength of the suture thread is deteriorated by the design of the needle. The suture thread has been known to snap when the surgeon apply to much pressure when tying. If the patient is suffering from subacromial impingement the jaw of the instrument can appear to be clumsy and hard to open. The jaw has sharp teeth which have been known to get stuck in the tendon. The surgeon must then perform an uncontrolled movement which might damage the tendon. The jaw limits the surgeons’ choice of thickness of the suture thread. The thickness of the needle used in the suture passer is limited to one size.  The purpose of the project is to develop a new concept that minimizes the risk for the patient and at the same time the concept should facilitate the work of the surgeon. The concept should meet the set requirements and be presented in the form of renderings of CAD-models and drawings. To achieve this process the instrument uses four different components. The needle, the jaw, the handle and an attachment between the needle and the handle.  Under heading 5, the generating process, each component presents to together with arguments of its design. The instrument consist of 25 components that are all developed from the ground up. The result should be viewed as a thorough concept that can be used for further development. It is recommended that the next step should be an investigation about material choice. When the material is specified a prototype should be manufacture and then used for testing.

The purpose of this study was to substantiate previous claims that differential growth across the frontonasal suture occurs and if this differential growth pattern is caused by an increased mitotic rate of the nasal bone. Two six week old New Zealand White Rabbits were given calcein 20mg/kg IA, demeclocycline 20mg/kg IA, and BrdU 40mg/kg IA on Days 1, 11, and 14, respectively. The animals were euthanized using Ketamine 31.6mg/kg IM and Pentobarbital 100mg/kg IV. The frontonasal suture was removed from the rabbit and divided into hemisections. The right hemisection was histologically processed using standard calcified methods which were modified and used for smaller bone sections at the Comparative Orthopaedic Research Laboratory, School of Veterinary Medicine, University of Wisconsin. The left hemisection was reserved for BrdU staining at the Central Microscopy Research Facility, University of Iowa. The resultant slides were imaged and photographed using an Olympus BX-40 microscope and measured using ImageJ software (NIH). Means and standard deviations were calculated for interlabel distance and mineral apposition rate (MAR). All frontonasal suture sites demonstrated double fluorochrome labeling. Samples F2-2 and M2-1 demonstrated the predicted differential growth pattern. Samples F2-1 and M2-2 did not. No suture sites demonstrated positive staining for BrdU. Although the sample size was small (n=2), this may demononstrate a trend toward differential growth of the suture. Due to the small sample size, the labeling protocol used in this study provided limited quantitative data. Although two sections did not demonstrate more bone deposition or faster mineral apposition rate of the nasal bone, it is important to consider that these sections were of poorer quality when compared to the other sections. Higher quality sections with clear, measurable margins showed a difference between frontal and nasal bone growth in both morphology and mineral apposition rate.

Today's medical textile market is producing state of the art polymeric textile implantable devices that are redefining traditional materials and methods of surgery. These sophisticated high-tech polymer materials are engineered for specific uses in surgical and interventional procedures. One of the new biotextile products is an absorbable bi-directional barbed surgical suture that does not require surgical knots for wound closure. This novel idea has the attention of many physicians and surgeons where wound closure or tissue approximation is needed. The barbed suture has the potential to change the way wound closure is perceived in various clinical fields of surgery and veterinary medicine.

The Central Asian Orogenic Belt formed by accretion subsequent to the contraction of the Palaeo-Asian Ocean that ultimately disappeared along the Solonker Suture Zone in East Asia. Since typical regional collisional features are absent, the tectonic evolution of the suture remains speculative. Integrated sedimentary provenance analyses across the accretionary collision zone between the Mongolian Arcs and the North China Craton place new constraints on the events that led to final suturing. An investigation on the geochronological and geochemical variability in Permian strata along a southeast-northwest transect revealed distinct differences across the Solonker Suture Zone: northern basins carry a broad Mesoproterozoic to latest Precambrian age signature, and their provenance terranes are of mixed juvenile to crustal magmatic origin. In contrast, southern basins contain detritus from the North China Craton, and their sources are of dominantly crustal contaminated magmatic origin. Provenance analysis suggests, that in the Early Palaeozoic (ca. 429 Ma) the Palaeo-Asian Ocean was consumed along the Uliastai Arc and the North China Craton, initiating the formation of the Northern and Southern Accretionary Orogens, respectively. By the end of the Middle Carboniferous the Mongolian Arcs consolidated after accretion of the Uliastai Arc. In the Late Carboniferous (ca. 314 Ma) the Hegenshan back-arc basin opened, detaching the Northern Accretionary Orogen. While subduction continued there, it may have temporarily ceased along the Southern Accretionary Orogen after accretion of a microcontinent (ca. 300 Ma). During the Middle Permian back-arc basin closure led to the formation and obduction of the Hegenshan supra-subduction zone ophiolite. Eventually, the Palaeo-Asian Ocean closed after wedge-wedge collision, which would not involve continental deep subduction, thus, leading to cryptic suturing from the Late Permian to Early Triassic. Statistical analyses on the heterogeneity and similarity of the age probability density functions require a complex Permian palaeo-geographic setting, involving a variety of arc basins, which received sediments dependent on the contemporary arc geometry. Early stages of the sequence likely resembled a Pacific-type scenario, including Japan-type back-arc basin opening, whereas the late stages were similar to the archipelago-type setting of present-day Southeast Asia. / published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy

The Yarlung (India-Asia) suture zone in southern Tibet records Middle Jurassic—Late Cretaceous development of the Lhasa terrane (Eurasian) convergent margin and subsequent India-Asia collision beginning in Paleocene time. This dissertation reports data from field-based geologic investigation of the Yarlung suture zone in the Lopu Range and Lazi Regions, ~600 and ~300 km west of the city of Lhasa, respectively. Field data were combined with new geochronology (detrital and igneous zircon U-Pb, garnet Lu-Hf), thermochronology (white mica Ar-Ar and zircon U-Th/He), and metamorphic petrology data to develop a tectonic model involving multiple episodes of shallow underthrusting, rollback, and breakoff of both oceanic and continental lithosphere. Switches between extensional and contractional deformation along the Yarlung suture zone appear to be controlled by changes in subduction dynamics. If this tectonic model is representative, then the tectonic process of inter-continental collision is responsible for much larger magnitudes of crustal recycling that previously thought. A hornblende-plagioclase-epidote paragneiss block in ophiolitic mélange, deposited during Middle Jurassic time, records Late Jurassic or Early Cretaceous subduction initiation along the Eurasian margin followed by Early Cretaceous forearc extension. Detrital zircons from Xigaze forearc basin strata deposited unconformably atop ophiolitic mélange produced a maximum depositional age of 97 ± 1 Ma, providing a minimum age for establishment of an arc-forearc-trench convergent margin along the southern Lhasa terrane. Metasedimentary rocks that were originally deposited along the Indian passive margin were subducted beneath the Lhasa terrane to upper-mantle depths, reaching high-pressure (HP), low-temperature conditions (≥1.4 GPa at T≤600 °C). Garnet Lu-Hf geochronology indicates that prograde metamorphism of the Indian metasedimentary rocks was ongoing at 40.4 ± 1.4 Ma while white mica Ar-Ar thermochronology indicates exhumation to mid-crustal depths between 39-34 Ma. Gangdese arc magmatism persisted after the onset of India-Asia collision, producing plutons that intruded sedimentary-matrix mélange of the southern Lhasa terrane subduction-accretion complex between 49-37 Ma. These data suggest steep subduction or southward trench retreat immediately prior to shutdown of arc magmatism along the Yarlung suture zone (37 Ma), shortly after the onset of high-pressure rock exhumation. We interpret that these data record a Paleocene—Eocene episode of southward rollback, breakoff, and underthrusting. During Oligocene—Miocene time, nonmarine strata were deposited along the Yarlung suture zone immediately prior to shortening across a system of out-of-sequence, top-north reverse faults. Based on our data and previous work, we interpret that sedimentation was driven by a second episode of rollback and breakoff of Indian continental lithosphere, whereas subsequent contractional deformation was driven by renewed shallow subduction. Compilation of regional thermochronological data and interpretation of seismic reflection data from previous investigations suggests that the top-north reverse faults comprise a foreland-dipping passive roof duplex above the leading edge of a structurally deeper, hinterland-dipping duplex beneath the southern Lhasa terrane. The Yarlung suture zone switched from north-south contraction to east-west extension by ~16 Ma based on a crosscutting relationship between a leucogranitic dike and a normal fault related to a larger horst structure in the Lopu Range region. Tectonic exhumation in the footwall block of the horst drove cooling through zircon (U-Th)/He closure temperature (~180 °C) between 12-6 Ma.

Suture anchors have been used successfully in many applications in orthopedics. They have been in the forefront of research in the recent years. Most of the studies, though, have focused on human suture anchors. This research concentrates on the veterinary aspect of suture anchors. Currently, there is no standardization of testing methods. One of the objectives of this research is to develop a standardized method of testing that is clinically relevant, at least for veterinary use. Another objective of this research is to compare the durability of three commercial suture anchors manufactured by Innovative Animal Products, Securos Veterinary Orthopedic Inc. and IMEXTM by comparing their pullout loads after cyclic loading. This research also aims to determine whether suture anchor failure due to eyelet cut-out or suture wear-out resulting from the sharp edges of the eyelet is the major cause of failure of bone-suture anchor-bone complexes. Cyclic loading of suture anchors during testing for durability has not been used previously even though such loading plays an important role in determining the stability of the bone-suture anchor-bone construct. The response of the construct to this type of testing followed by pullout tests has been explored in this research.

Suture anchors have been used successfully in many applications in orthopedics. They have been in the forefront of research in the recent years. Most of the studies, though, have focused on human suture anchors. This research concentrates on the veterinary aspect of suture anchors. Currently, there is no standardization of testing methods. One of the objectives of this research is to develop a standardized method of testing that is clinically relevant, at least for veterinary use. Another objective of this research is to compare the durability of three commercial suture anchors manufactured by Innovative Animal Products, Securos Veterinary Orthopedic Inc. and IMEXTM by comparing their pullout loads after cyclic loading. This research also aims to determine whether suture anchor failure due to eyelet cut-out or suture wear-out resulting from the sharp edges of the eyelet is the major cause of failure of bone-suture anchor-bone complexes. Cyclic loading of suture anchors during testing for durability has not been used previously even though such loading plays an important role in determining the stability of the bone-suture anchor-bone construct. The response of the construct to this type of testing followed by pullout tests has been explored in this research.

Thesis (Ph.D.)--University of Wyoming, 2007. / Title from PDF title page (viewed on June 17, 2009). Includes bibliographical references.

Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 199-230) Also available in print.

Thesis (M. Phil.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.