28 research outputs found

    Spatial Sensors for Quantitative Assessment of Retrieved Arthroplasty Bearings

    Get PDF
    Evaluation of retrieved joint arthroplasty bearings provides unique evidence related to the physiological environment in which bearing materials are expected to perform. This dissertation describes the development of novel spatial sensors and measurement strategies for standardized, quantitative assessments of arthroplasty bearings, including total knee replacements, unicompartmental knee replacements, and total hip replacements. The approach is to assess bearings that endured a finite duration of function in patients, with particular emphasis on expanding our understanding of the biomechanical conditions specific to bearing function and wear in the physiological environment. Several quantifiable parameters are identified that prove comparable to pre-clinical in vitro tibological evaluations, including knee wear simulation and analytical modeling. These comparisons provide clinical relevance to the existing methodologies, helping to verify that the biomechanical simulations accurately represent the in vivo conditions they are meant to simulate. The broad objective of this dissertation is to improve the longevity and function of arthroplasty bearing materials and designs. Assessments from the retrieved prostheses are discussed within the context of developing comprehensive approaches for the prospective evaluation of new materials and designs in joint replacements

    A clinical investigation of conservative total hip replacement : senior honors thesis [(HONRS 499)]

    Get PDF
    There is no abstract available for this thesis.Honors CollegeThesis (B.?.

    Clemson University Retrieval of Explants Program and Registry in Orthopaedics (CU-REPRO)

    Get PDF
    The Clemson University Retrieval of Explants Program and Registry in Orthopaedics (CU-REPRO) is a student-led creative inquiry program created in 2008. CU-REPRO is a working repository of more than 500 explanted joint replacements collected from cooperative partnerships with 11 hospitals in South Carolina. This program provides an exciting opportunity for students to work with orthopedic surgical teams to collect and process explanted medical devices. This program allows students to explore clinical problems associated with surgical and patient variables, and develop the tools and techniques for systematic evaluation of implant designs, biomaterials, and function. It is one of only a few implant retrieval programs in the country and distinguishes itself by incorporating undergraduate education, biomaterials research and community outreach in its mission. This year, CU-REPRO began research into hip replacements to determine reasons why a subset of explanted femoral stems were received with mid-stem fractures. Review of clinical records revealed that some stems were cut during revision surgery to aid removal while others endured fatigue fractures while in the patients. This semester, the engineering significance of this finding will be explored, as related to loading conditions, stem size and material. The goal is to publish these findings in a suitable orthopaedics journal and make a meaningful scientific contribution. The REPRO team would like to thank the Clemson University Creative Inquiry program for the opportunity to continue to build the growing registry and to expand the program to include research projects

    Innervation Changes Induced by Inflammation in the Murine Vagina

    Get PDF
    © 2018 IBRO. Published by Elsevier Ltd. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/ This author accepted manuscript is made available following 12 month embargo from date of publication (January 2018) in accordance with the publisher’s archiving policyVulvodynia is a prevalent chronic pain disorder associated with high medical costs and often ineffective treatments. The major pathological feature is proliferation of vaginal nerve fibers. This study aimed to develop a highly reproducible animal model to study neuroproliferation in the vagina and aid the identification of appropriately targeted treatments for conditions such as vulvodynia. Mild chronic inflammation was induced using microinjection of complete Freund’s adjuvant in the distal vagina of C57Bl/6 mice. Control mice received saline. Inflammation and innervation density were assessed at 7 and 28 days after a single administration or 14 days following repeated administration of complete Freund’s adjuvant or saline. Histochemistry and blinded-analysis of images were used to assess vaginal morphology (H & E) and abundance of macrophages (CD68-labeling), mast cells (toluidine blue staining, mast cell tryptase-immunoreactivity), blood vessels (αSMA-immunoreactivity) and nerve fibers immunoreactive for the pan-neuronal marker PGP9.5. Subpopulations of nerve fibers were identified using immunoreactivity for calcitonin gene-related peptide (CGRP), substance P (SP), vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY). Single administration of complete Freund’s adjuvant resulted in vaginal swelling, macrophage infiltration, vascular proliferation and increased abundance of nerve fibers immunoreactive for CGRP, SP, VIP and/or PGP9.5 but not NPY, evident at seven days. Inflammation further increased following repeated administration of complete Freund’s adjuvant but nerve fiber proliferation did not. Nerve fiber proliferation continued to be evident at 28 days. The inter-individual differences within each treatment group were small, indicating that this model may be useful to study mechanisms underlying vaginal nerve fiber proliferation associated with inflammation

    Total Knee Arthroplasty Designed to Accommodate the Presence or Absence of the Posterior Cruciate Ligament

    No full text
    Evidence for selecting the same total knee arthroplasty prosthesis whether the posterior cruciate ligament (PCL) is retained or resected is rarely documented. This study reports prospective midterm clinical, radiographic, and functional outcomes of a fixedbearing design implanted using two different surgical techniques. The PCL was completely retained in 116 knees and completely resected in 43 knees. For the entire cohort, clinical knee (96±7) and function (92±13) scores and radiographic outcomes were good to excellent for 84% of patients after 5-10 years in vivo. Range of motion averaged 124 ∘ ±9 ∘ , with 126 knees exhibiting ≥ 120 ∘ flexion. Small differences in average knee flexion and function scores were noted, with the PCL-resected group exhibiting an average of 5 ∘ more flexion but an average function score that was 7 points lower compared to the PCL-retained group. Fluoroscopic analysis of 33 knees revealed stable tibiofemoral translations. This study demonstrates that a TKA articular design with progressive congruency in the lateral compartment can provide for femoral condyle rollback in maximal flexion activities and achieve good clinical and functional performance in patients with PCL-retained and PCL-resected TKA. This TKA design proved suitable for use with either surgical technique, providing surgeons with the choice of maintaining or sacrificing the PCL

    Total knee arthroplasty designed to accommodate the presence or absence of the posterior cruciate ligament.

    No full text
    Evidence for selecting the same total knee arthroplasty prosthesis whether the posterior cruciate ligament (PCL) is retained or resected is rarely documented. This study reports prospective midterm clinical, radiographic, and functional outcomes of a fixed-bearing design implanted using two different surgical techniques. The PCL was completely retained in 116 knees and completely resected in 43 knees. For the entire cohort, clinical knee (96 ± 7) and function (92 ± 13) scores and radiographic outcomes were good to excellent for 84% of patients after 5-10 years in vivo. Range of motion averaged 124° ± 9°, with 126 knees exhibiting ≥120° flexion. Small differences in average knee flexion and function scores were noted, with the PCL-resected group exhibiting an average of 5° more flexion but an average function score that was 7 points lower compared to the PCL-retained group. Fluoroscopic analysis of 33 knees revealed stable tibiofemoral translations. This study demonstrates that a TKA articular design with progressive congruency in the lateral compartment can provide for femoral condyle rollback in maximal flexion activities and achieve good clinical and functional performance in patients with PCL-retained and PCL-resected TKA. This TKA design proved suitable for use with either surgical technique, providing surgeons with the choice of maintaining or sacrificing the PCL

    Re-use of explanted osteosynthesis devices: A reliable and inexpensive reprocessing protocol

    No full text
    Introduction: Orthopaedic surgical treatments emphasizing immobilization using open reduction and internal fixation with osteosynthesis devices are widely accepted for their efficacy in treating complex fractures and reducing permanent musculoskeletal deformity. However, such treatments are profoundly underutilized in low- and middle-income countries (LMIC), partially due to inadequate availability of the costly osteosynthesis devices. Orthopaedic surgeons in some LMIC regularly re-use osteosynthesis devices in an effort to meet treatment demands, even though such devices typically are regulated for single-use only. The purpose of this study is to report a reprocessing protocol applied to explanted osteosynthesis devices obtained at a leading trauma care hospital. Methods: ExplantedosteosynthesisdeviceswereidentifiedthroughaRegisterofExplantedOrthopaedic Prostheses. Guidelines to handle ethical issues were approved by the local Ethical Committee and informed patient consent was obtained at the time of explant surgery. Primary acceptance criteria were established and applied to osteosynthesis devices explanted between 2005 and 2008. A rigorous protocol for conducting decontamination and visual inspection based on specific screening criteria was implemented using simple equipment that is readily available in LMIC. Results: Atotalof2050osteosynthesisdevices,includingalargevarietyofplates,screwsandstaples,were reprocessed using the decontamination and inspection protocols. The acceptance rate was 66%. Estimated labour time and implementation time of the protocol to reprocess a typical osteosynthesis unit (1 plate and 5 screws) was 25 min, with an estimated fixed cost (in Italy) of s10 per unit for implementing the protocol, plus an additional s5 for final sterilization at the end-user hospital site. Discussion: This study was motivated by the treatment demands encountered by orthopaedic surgeons providing medical treatment in several different LMIC and their need for access to basic osteosynthesis devices. The rigorous decontamination protocol and generalized inspection criteria proved useful for efficiently screening a large volume of devices. Given that re-used osteosynthesis devices can yield satisfactory results, this study addresses potential complications of re-used devices and valid concerns that relate to patient safety. Implementing this defined reprocessing protocol into existing re-use practises in LMIC helps to limit the risks of inadequate sterilization and structural failure without adding additional risks to patients receiving re-used devices
    corecore