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1.
J Arthroplasty ; 39(7): 1777-1782, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38642851

RESUMO

BACKGROUND: Symptoms of depression have been associated with greater incapability following total hip arthroplasty (THA). A brief, 2-question, measure of symptoms of depression - the Patient Health Questionnaire-2 (PHQ-2) - may be sufficient to measure associations with the magnitude of incapability during recovery from THA. This study investigated whether preoperative symptoms of depression (measured with the PHQ-2) correlated with levels of incapability 6 weeks and 6 months after THA, accounting for demographic and clinical factors. METHODS: We performed a prospective cohort study across 5 centers and recruited 101 patients undergoing THA, of whom 90 (89%) completed follow-up. Patients completed demographics, a preoperative 2-item (PHQ-2) measure of symptoms of depression, and the Hip Dysfunction and Osteoarthritis Outcome Score for Joint Replacement (HOOS JR) at 6-weeks and 6-months postoperatively. Negative binomial regression models determined factors associated with HOOS JR at 6 weeks and 6 months, accounting for potential confounders. RESULTS: Accounting for potential confounding factors, we found that higher preoperative PHQ-2 scores (reflecting greater symptoms of depression) were associated with lower HOOS JR scores (reflecting a greater level of hip disability) at both 6 weeks (regression coefficient = -0.67, P < .001) and 6 months (regression coefficient = -1.9, P < .001) after THA. CONCLUSIONS: Symptoms of depression on a 2-question preoperative questionnaire are common, and greater symptoms of depression are associated with reduced capability within the first year following THA. These findings support the prioritization of routine mental health assessments before THA. Measuring mindset using relatively brief instruments will be important considering the current shift toward implementing self-reported measures of health status in clinical practice and incorporating them within alternative payment models.


Assuntos
Artroplastia de Quadril , Depressão , Osteoartrite do Quadril , Humanos , Artroplastia de Quadril/psicologia , Artroplastia de Quadril/efeitos adversos , Feminino , Osteoartrite do Quadril/cirurgia , Osteoartrite do Quadril/psicologia , Masculino , Depressão/etiologia , Depressão/psicologia , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Período Pré-Operatório , Inquéritos e Questionários , Recuperação de Função Fisiológica , Resultado do Tratamento
2.
J Arthroplasty ; 38(7 Suppl 2): S405-S411, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37257789

RESUMO

BACKGROUND: Functional antibiotic hip spacers for treatment of periprosthetic joint infection may be retained in patients deemed too sick for reimplantation, or who elect to forego additional surgery. Our aim was to characterize reoperations, modes of failure, and function outcomes in patients who have retained hip spacers. METHODS: We performed a retrospective review of 43 hips that underwent placement of an articulating hip spacer between January 1, 2014 and November 30, 2021. There were 28 hips that completed 2-stage exchange (TS group) and were reimplanted at mean 4 months (range, 2 to 10). The other 15 hips underwent planned spacer retention (RS group). Mean follow-up was 2.9 years (range, 1 to 6.1 years). The RS group was older (74 versus 66 years, P = .005) and had a higher age-adjusted Charlson Comorbidity Index (4.4 versus 3.3, P = .04) compared with the TS group. RESULTS: Overall survivorship free of reinfection was 91% at 1 year and 86% at 5 years. There were 6 RS hips that underwent reimplantation for spacer failure at a mean of 23 months (range, 6 to 71 months) and 8 had radiographic stem loosening/subsidence. Patients who had a retained spacer at final follow-up were more likely to require a walker (P = .005) or wheelchair (P = .049) compared with patients who underwent reimplantation. CONCLUSIONS: Retained hip spacers can decrease overall surgical burden, but are associated with high rates of stem loosening, subsidence, and unplanned reoperation. Planned spacer retention should be undertaken with caution in patients healthy enough to undergo reimplantation.


Assuntos
Artrite Infecciosa , Artroplastia de Quadril , Prótese de Quadril , Infecções Relacionadas à Prótese , Humanos , Reoperação , Artroplastia de Quadril/efeitos adversos , Antibacterianos/uso terapêutico , Prótese de Quadril/efeitos adversos , Artrite Infecciosa/cirurgia , Estudos Retrospectivos , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/cirurgia , Resultado do Tratamento
3.
J Arthroplasty ; 38(6): 998-1003, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36535446

RESUMO

BACKGROUND: Conversion hip arthroplasty is defined as a patient who has had prior open or arthroscopic hip surgery with or without retained hardware that is removed and replaced with arthroplasty components. Currently, it is classified under the same diagnosis-related group as primary total hip arthroplasty (THA); however, it frequently requires a higher cost of care. METHODS: A retrospective study of 228 conversion THA procedures in an orthopaedic specialty hospital was performed. Propensity score matching was used to compare the study group to a cohort of 510 primary THA patients by age, body mass index, sex, and American Society of Anesthesiologists score. These matched groups were compared based on total costs, implants used, operative times, length of stay (LOS), readmissions, and complications. RESULTS: Conversion THA incurred 25% more mean total costs compared to primary THA (P < .05), longer lengths of surgery (154 versus 122 minutes), and hospital LOS (2.1 versus 1.56 days). A subgroup analysis showed a 57% increased cost for cephalomedullary nail conversion, 34% increased cost for sliding hip screw, 33% for acetabular open reduction and internal fixation conversion, and 10% increased costs in closed reduction and percutaneous pinning conversions (all P < .05). There were 5 intraoperative complications in the conversion group versus none in the primary THA group (P < .01), with no statistically significant difference in readmissions. CONCLUSION: Conversion THA is significantly more costly than primary THA and has longer surgical times and greater LOS. Specifically, conversion THA with retained implants had the greatest impact on cost.


Assuntos
Artroplastia de Quadril , Humanos , Artroplastia de Quadril/efeitos adversos , Estudos Retrospectivos , Grupos Diagnósticos Relacionados , Complicações Intraoperatórias , Tempo de Internação , Complicações Pós-Operatórias/etiologia
4.
Adv Biol (Weinh) ; 6(3): e2101078, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35119218

RESUMO

Many helminth life cycles, including hookworm, involve a mandatory lung phase, where myeloid and granulocyte subsets interact with the helminth and respond to infection-induced lung injury. To evaluate these innate subsets in Nippostrongylus brasiliensis infection, reporter mice for myeloid cells (CX3CR1GFP ) and granulocytes (PGRPdsRED ) are employed. Nippostrongylus infection induces lung infiltration of reporter cells, including CX3CR1+ myeloid cells and PGRP+ eosinophils. Strikingly, CX3CR1GFP/GFP mice, which are deficient in CX3CR1, are protected from Nippostrongylus infection with reduced weight loss, lung leukocyte infiltration, and worm burden compared to CX3CR1+/+ mice. This protective effect is specific for CX3CR1 as CCR2-deficient mice do not exhibit reduced worm burdens. Nippostrongylus co-culture with lung Ly6C+ monocytes or CD11c+ cells demonstrates that CX3CR1GFP/GFP monocytes secrete more pro-inflammatory cytokines and actively bind the parasites causing reduced motility. RNA sequencing of Ly6C+ or CD11c+ cells shows Nippostrongylus-induced gene expression changes, particularly in monocytes, associated with inflammation, chemotaxis, and extracellular matrix remodeling pathways. Analysis reveals cytotoxic and adhesion molecules as potential effectors against the parasite, such as Gzma and Gzmb, which are elevated in CX3CR1GFP/GFP monocytes. These studies validate a dual innate cell reporter for lung helminth infection and demonstrate that CX3CR1 impairs monocyte-helminth interaction.


Assuntos
Monócitos , Pneumonia , Animais , Antígeno CD11c/metabolismo , Receptor 1 de Quimiocina CX3C/genética , Camundongos , Camundongos Endogâmicos C57BL , Células Mieloides/metabolismo , Nippostrongylus/metabolismo , Pneumonia/metabolismo
5.
J Arthroplasty ; 35(6S): S138-S143, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32173619

RESUMO

BACKGROUND: Given the opioid crisis in America, patients are trying alternative medications including tetrahydrocannabinol (THC) and other cannabidiol (CBD) containing products in the perioperative period, especially in states where these products are legal. This study sought to analyze usage rates of CBD/THC products in the perioperative period for primary unilateral total hip and knee arthroplasty (THA/TKA) patients and identify a possible association with post-operative opioid use. METHODS: A prospective cohort of primary unilateral THA/TKA patients were enrolled at a single institution. Patients who completed detailed pain journals were retrospectively surveyed for CBD/THC product usage. Pain medications were converted to morphine milligram equivalents (MME). RESULTS: Data from 195 of the 210 patients (92.9% response rate) following primary arthroplasty were analyzed. Overall, 16.4% of arthroplasty-22.6% (n = 19) of TKA and 11.7% (n = 13) of THA-patients used CBD/THC products in the perioperative period. There was a wide variety of usage patterns among those using CBD/THC products. In comparing CBD/THC users and non-users, there was no significant difference in the length of narcotic use, total morphine milligram equivalents taken, narcotic pills taken, average post-op pain scores, the percentage of patients requiring a refill of narcotics, or length of stay. CONCLUSION: Understanding that CBD/THC usage was not consistent for patients who used these products, 22.6% of TKA and 11.7% of THA patients tried CBD/THC products in the perioperative period. In this small sample, CBD/THC use was not associated with a major effect on narcotic requirements. Further studies on the effects of CBD/THC are needed as these therapies become more widely available.


Assuntos
Artroplastia do Joelho , Canabidiol , Artroplastia do Joelho/efeitos adversos , Dronabinol , Humanos , Período Perioperatório , Estudos Prospectivos , Estudos Retrospectivos
6.
J Arthroplasty ; 35(6S): S226-S230, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32173620

RESUMO

BACKGROUND: The opioid crisis pressures orthopedic surgeons to reduce the amount of narcotics prescribed for postoperative pain management. This study sought to quantify postoperative opioid use after hospital discharge for primary unilateral total hip arthroplasty (THA) patients. METHODS: A prospective cohort of primary unilateral THA patients were enrolled at a single institution. Detailed pain journals tracked all prescription and over-the-counter pain medication, quantity, frequency, and visual analog scale pain scores. Pain medications were converted to morphine milligram equivalents (MME). RESULTS: Data from 121 subjects were analyzed; the average visual analog scale pain score was 3.44 while taking narcotics. The average number of days taking narcotics was 8.46 days. The distribution of days taking narcotics was right shifted with 50.5% of patients off narcotics after 1 week, and 82.6% off by 2 weeks postoperatively. The average number of narcotic pills prescribed was significantly greater than narcotic pills taken (72.5 vs 28.8, P < .0001). The average MME prescribed was significantly greater than MME taken (452.1 vs 133.8, P < .0001). The average excess narcotic pills prescribed per patient was 51.7 pills. And 71.9% took fewer than 30 narcotic pills; 90.9% patients took fewer than 50 narcotic pills. Also, 10.7% did not require any narcotics; 9.9% required a refill of narcotics; and 33.1% went home the day of surgery. CONCLUSION: Significantly more narcotics were prescribed than were taken in the postoperative period following THA with an average 51.7 excess narcotic pills per patient. Adjusting prescribing patterns to match patient narcotic usage could reduce the excess narcotic pills following THA.


Assuntos
Artroplastia de Quadril , Analgésicos Opioides/uso terapêutico , Artroplastia de Quadril/efeitos adversos , Humanos , Prescrição Inadequada , Dor Pós-Operatória/tratamento farmacológico , Alta do Paciente , Padrões de Prática Médica , Estudos Prospectivos
7.
J Arthroplasty ; 35(6S): S158-S162, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32171491

RESUMO

BACKGROUND: The opioid crisis pressures orthopedic surgeons to reduce the amount of narcotics prescribed for post-operative pain management. This study sought to quantify post-operative opioid use after hospital discharge for primary unilateral total knee arthroplasty (TKA) patients. METHODS: A prospective cohort of primary unilateral TKA patients performed by one of 5 senior fellowship-trained arthroplasty surgeons were enrolled at a single institution. Detailed pain journals tracked all prescriptions and over-the-counter pain medications, quantities, frequencies, and visual analog scale pain scores. Narcotic and narcotic-like pain medications were converted to morphine milligram equivalents (MME). Statistical analysis was performed using Student's t-test with α < 0.05. RESULTS: Data from 89 subjects were analyzed; the average visual analog scale pain score was 6.92 while taking narcotics. The average number of days taking narcotics was 16.8 days. The distribution of days taking narcotics was right shifted with 52.8% of patients off narcotics after 2 week, and 74.2% off by 3 weeks post-op. The average MME prescribed was significantly greater than MME taken (866.6 vs 428.2, P < .0001). The average number of narcotic pills prescribed was significantly greater than narcotic pills taken (105.1 vs 52.0, P < .0001). The average excess narcotic pills prescribed per patient was 53.1 pills. About 48.3% took fewer than 40 narcotic pills; 75.3% took fewer than 75 narcotic pills. About 3.4% did not require any narcotics; 40.5% required a refill of narcotics. Also, 9.0% went home the day of surgery. CONCLUSION: Significantly more narcotics were prescribed than were taken in the post-operative period following TKA with an average 53.1 excess narcotic pills per patient. Adjusting prescribing patterns to match patient narcotic usage could reduce the excess narcotic pills following TKA.


Assuntos
Artroplastia do Joelho , Analgésicos Opioides/uso terapêutico , Artroplastia do Joelho/efeitos adversos , Humanos , Prescrição Inadequada , Dor Pós-Operatória/tratamento farmacológico , Alta do Paciente , Padrões de Prática Médica , Estudos Prospectivos
8.
Inorg Chem ; 58(3): 1728-1732, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30649872

RESUMO

Novel mixed-ligand rhodium(II) paddlewheel complexes incorporating tethered axial thioether ligands have been synthesized and characterized. The thioether moiety is essential for high yields and the suppression of byproducts in cyclopropanation reactions using an electron-deficient diazoacetate. Crystal structures, UV-vis analysis, and cyclic voltammetry experiments shed light on the catalytic performance of the complexes.

9.
J Leukoc Biol ; 104(4): 855-869, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29992625

RESUMO

Resistin-like molecule α (RELMα) is a highly secreted protein in type 2 (Th2) cytokine-induced inflammation including helminth infection and allergy. In infection with Nippostrongylus brasiliensis (Nb), RELMα dampens Th2 inflammatory responses. RELMα is expressed by immune cells, and by epithelial cells (EC); however, the functional impact of immune versus EC-derived RELMα is unknown. We generated bone marrow (BM) chimeras that were RELMα deficient (RELMα-/- ) in BM or non BM cells and infected them with Nb. Non BM RELMα-/- chimeras had comparable inflammatory responses and parasite burdens to RELMα+/+ mice. In contrast, both RELMα-/- and BM RELMα-/- mice exhibited increased Nb-induced lung and intestinal inflammation, correlated with elevated Th2 cytokines and Nb killing. CD11c+ lung macrophages were the dominant BM-derived source of RELMα and can mediate Nb killing. Therefore, we employed a macrophage-worm co-culture system to investigate whether RELMα regulates macrophage-mediated Nb killing. Compared to RELMα+/+ macrophages, RELMα-/- macrophages exhibited increased binding to Nb and functionally impaired Nb development. Supplementation with recombinant RELMα partially reversed this phenotype. Gene expression analysis revealed that RELMα decreased cell adhesion and Fc receptor signaling pathways, which are associated with macrophage-mediated helminth killing. Collectively, these studies demonstrate that BM-derived RELMα is necessary and sufficient to dampen Nb immune responses, and identify that one mechanism of action of RELMα is through inhibiting macrophage recruitment and interaction with Nb. Our findings suggest that RELMα acts as an immune brake that provides mutually beneficial effects for the host and parasite by limiting tissue damage and delaying parasite expulsion.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Infecções por Strongylida/imunologia , Trifosfato de Adenosina/metabolismo , Células Epiteliais Alveolares/metabolismo , Animais , Adesão Celular , Células Cultivadas , Técnicas de Cocultura , Células Dendríticas/metabolismo , Feminino , Regulação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular/deficiência , Peptídeos e Proteínas de Sinalização Intercelular/genética , Macrófagos Alveolares/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nippostrongylus/isolamento & purificação , Nippostrongylus/ultraestrutura , Quimera por Radiação , Proteínas Recombinantes/metabolismo , Infecções por Strongylida/parasitologia , Células Th2/imunologia
10.
J Arthroplasty ; 33(3): 800-804, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29137901

RESUMO

BACKGROUND: An increased rate of complications related to femoral component failure has been described with less invasive total hip arthroplasty (THA). This study evaluated the incidence of femoral complications associated with the direct anterior approach for THA. METHODS: Retrospective review was performed of the initial 1120 consecutive patients who underwent direct anterior THA by 2 surgeons. RESULTS: A total of 899 patients (80.3%) had a 2-year follow-up (range, 2-8 years). Complications within 90 days occurred in 20 patients (1.8%): 10 calcar fractures, 1 greater trochanter fracture, 1 canal perforation, 3 hematomas, 2 dislocations, 2 superficial, and 1 deep infection. Nine patients (1%) underwent revision: 5 for aseptic femoral loosening (0.55%), 1 for periprosthetic joint infection, 1 for dislocation, 1 for hip flexor irritation, and 1 for a damaged polyethylene liner. Of the 5 patients with aseptic femoral loosening, 3 had a short, mediolateral tapered stem, 1 cemented stem, and 1 S-ROM stem placed to bypass a canal perforation. There were no revisions for aseptic loosening in the collared, fully hydroxyapatite (HA)-coated compaction broached or triple tapered proximal fit and fill stem designs (70.6% of all stems). Revision rate for femoral loosening was significantly higher for tapered wedge over HA-coated, compaction broached stems (P < .005). CONCLUSION: Pain and function improved predictably with a 0.55% rate of femoral loosening at 2-year follow-up. Among collared, fully HA-coated and triple taper fit and fill femoral stems, there were no instances of revision for aseptic loosening vs 3 in the short stem, collarless mediolateral tapered group.


Assuntos
Artroplastia de Quadril , Fêmur/cirurgia , Prótese de Quadril , Desenho de Prótese , Falha de Prótese , Idoso , Artrite Infecciosa/cirurgia , Durapatita/química , Feminino , Seguimentos , Fraturas Ósseas/cirurgia , Hematoma/cirurgia , Humanos , Incidência , Luxações Articulares/cirurgia , Masculino , Pessoa de Meia-Idade , Polietileno/química , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
11.
J Arthroplasty ; 31(1): 132-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26297690

RESUMO

68 patients (91 primary total knee arthroplasties) were evaluated at a mean 10-year, minimum 5 year follow up in patients younger than sixty years of age utilizing the gap balanced, rotating platform design. Follow up assessment included implant survivorship, adverse events, x-rays, Knee Society rating system and clinical evaluation. Three revisions were performed with only one for aseptic loosening at 45 months. Two manipulations were performed in the early postoperative period. Survivorship of the rotating platform, gap balanced knee was 96.7% using surgical revision for any reason and 98.9% using aseptic loosening as endpoints. The rotating platform design using the gap balancing technique in young patients had excellent survivorship at 10-year mean follow up.


Assuntos
Artroplastia do Joelho/métodos , Falha de Prótese , Adulto , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Articulação do Joelho/cirurgia , Prótese do Joelho , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/cirurgia , Estudos Prospectivos , Reoperação/instrumentação , Índice de Gravidade de Doença , Resultado do Tratamento , Raios X
12.
Orthopedics ; 38(7): e611-5, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26186324

RESUMO

Simultaneous bilateral total hip arthroplasty (THA) has been performed successfully, with good outcomes and low complication rates reported. Most published studies on the topic used anterolateral or posterior surgical approaches. The anterior approach is performed under live fluoroscopy with the patient supine, obviating the need for patient repositioning during bilateral surgery. The authors report their experience with simultaneous bilateral anterior approach total hip arthroplasty. The authors retrospectively reviewed data for 75 patients (150 hips). Mean follow-up was 26 months (range, 5-60 months). Mean patient age was 59 years and the majority were American Society of Anesthesiology class 2 (range, 1-3). Mean total surgical time was 144 minutes (72 minutes per hip). Mean blood loss was 565 mL. Mean hospital length of stay was 2.75 days (range, 1-4 days). Ninety-six percent of patients were able to ambulate on postoperative day 1. Sixty-eight percent of patients were discharged to home. Mean Harris Hip Score improved from 50 to 97. All patients noted a return to preoperative level of activity or higher. Complications included 1 atraumatic minimally displaced trochanteric fracture occurring 2 weeks postoperatively, 1 pulmonary embolism on postoperative day 3 treated without sequelae, 1 episode of postoperative atrial fibrillation, and 4 minor local wound complications. No readmission, infection, nerve palsy, dislocation, reoperation, or death occurred. Anterior approach THA has the advantage of a single supine position for bilateral simultaneous surgery and the current study supports its use in appropriate patients.


Assuntos
Artroplastia de Quadril/métodos , Osteoartrite do Quadril/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
J Arthroplasty ; 29(6): 1219-24, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24444570

RESUMO

Stepped porous titanium metaphyseal sleeves may provide an option for enhanced fixation in managing challenging tibial defects in revision total knee arthroplasty (TKA). We retrospectively reviewed data on 51 patients who underwent revision TKA utilizing a metaphyseal sleeve for Anderson Orthopaedic Research Institute (AORI) Type II and III tibial defects between June 2007 and July 2011. Of these 51 patients, 36 patients had complete clinical and radiographic data. At final follow-up (mean: 38 months) significant improvements in knee range of motion and Knee Society scores were observed postoperatively (P < 0.001). Four revision procedures were necessary, but none for aseptic implant fixation failure. Radiographic review at final follow-up revealed stable, osteointegrated components without component migration or clinically significant osteolysis. Metaphyseal sleeve use in the management of moderate to severe tibial defects in revision TKA resulted in satisfactory clinical outcomes and is a versatile option for achieving stable fixation.


Assuntos
Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/instrumentação , Reabsorção Óssea/cirurgia , Idoso , Idoso de 80 Anos ou mais , Materiais Biocompatíveis , Feminino , Humanos , Articulação do Joelho/cirurgia , Prótese do Joelho , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Reoperação , Tíbia/cirurgia , Titânio
14.
Pulm Circ ; 2(1): 41-53, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22558519

RESUMO

Membrane depolarization is critical to pulmonary arterial (PA) contraction. Both L-type Ca(2+) channels (Ca(L)) and Rho-kinase are important signaling components of this process and mitochondrial and non-mitochondrial generated superoxides can be part of the signaling process. Maturation and long-term hypoxia (LTH) each can modify depolarization-dependent contraction and the role of superoxides. By the use of wire myography, we tested the hypothesis that maturation and LTH increase pulmonary arterial reactivity to high-K(+)-induced membrane depolarization through enhancements in the importance of Ca(L)and Rho-kinase-dependent pathways. The data show that maturation, but not LTH, increases contraction to 125 mM KCl (high-K(+)) without altering the EC(50). High-K(+)-dependent contraction was inhibited to a similar extent in fetal and adult PA by multiple Ca(L) blockers, including 10 µM diltiazem, 10 µM verapamil, and 10 µM nifedipine. Postnatal maturation increased the role for 10 µM nifedipine-sensitive Ca(L), and decreased that for 10 µM Y-27632-sensitive Rho-kinase. In all groups, the combination of nifedipine and Y-27632 effectively inhibited high-K(+) contraction. Tempol (3 mM) but not 100 µM apocynin slightly reduced contraction in arteries from fetal hypoxic and adult normoxic and hypoxic sheep, indicating a limited role for non-mitochondrial derived superoxide to high-K(+)-induced contraction. Western immunoblot for alpha smooth muscle actin indicated small increases in relative abundance in the adult. The data suggest that while Ca(L) therapies more effectively vasodilate PA in adults and rho-kinase therapies are more effective in newborns, combination therapies would provide greater efficacy in both young and mature patients regardless of normoxic or hypoxic conditions.

15.
Clin Orthop Relat Res ; 463: 26-30, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17960672

RESUMO

Computer-assisted techniques have been successfully used in many surgical procedures. More recently, computer-assisted surgery has been used to improve the accuracy and reproducibility of implant alignment in total hip and knee arthroplasty procedures. However, the impact of computer-assisted surgery on long-term clinical outcomes and implant survivorship in total joint arthroplasty has yet to be documented. The adoption of computer-assisted surgical systems for use in total joint arthroplasty will be heavily influenced by the economic impact on the various stakeholders in the health-care system. Currently, there are mixed financial incentives for surgeons, hospitals, and payers to adopt and use computer-assisted surgical techniques for total joint arthroplasty. Careful consideration of the impact of computer-assisted surgery on surgeon and hospital productivity as well as the financial contribution of this technology to hospital profit margins would provide valuable insight into the adoption and widespread use of computer-assisted surgery.


Assuntos
Artroplastia de Quadril/economia , Artroplastia do Joelho/economia , Eficiência Organizacional , Custos de Cuidados de Saúde , Ortopedia/economia , Cirurgia Assistida por Computador/economia , Artroplastia de Quadril/métodos , Artroplastia do Joelho/métodos , Eficiência Organizacional/estatística & dados numéricos , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Prótese Articular/economia , Ortopedia/métodos , Cirurgia Assistida por Computador/estatística & dados numéricos
16.
Clin Orthop Relat Res ; 452: 65-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16906095

RESUMO

Although various techniques are advocated to establish tibial rotational alignment during total knee arthroplasty, it is unknown which is most repeatable. We evaluated the precision and accuracy of five tibial rotational alignment techniques to determine whether computer-assisted navigation systems can reduce variability of tibial component rotational alignment when compared to traditional instrumentation. Eleven orthopaedic surgeons used four computer-assisted techniques that required identification of anatomical landmarks and one that used traditional extramedullary instrumentation to establish tibial rotational alignment axes on 10 cadaver legs. Two computer-assisted techniques (axes between the most medial and lateral border of the tibial plateau, and between the posterior cruciate ligament [PCL] and the anterior tibial crest) and the traditional technique were least variable, with standard deviations of 9.9 degrees, 10.8 degrees, and 12.1 degrees, respectively. Computer-assisted techniques referencing the tibial tubercle (axes between the PCL and the medial border or medial 1/3 of the tubercle) were most variable, with standard deviations of 27.4 degrees and 28.1 degrees. The axis between the medial border of the tibial tubercle and the PCL was internally rotated compared to the other techniques. None of the techniques consistently established tibial rotational alignment, and navigation systems that establish rotational alignment by identifying anatomic landmarks were not more reliable than traditional instrumentation.


Assuntos
Artroplastia do Joelho , Articulação do Joelho/fisiologia , Articulação do Joelho/cirurgia , Amplitude de Movimento Articular , Tíbia/fisiologia , Cadáver , Humanos
17.
J Bone Joint Surg Am ; 87(10): 2276-80, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16203894

RESUMO

BACKGROUND: Several reference axes are used to establish femoral rotational alignment during total knee arthroplasty, but debate continues with regard to which axis is most accurately and easily identified during surgery. Computer-assisted navigation systems have been developed in an attempt to more accurately and consistently align implants during total knee arthroplasty, but it is unknown if navigation systems can improve the accuracy of femoral rotational alignment as compared with that achieved with more traditional techniques involving mechanical guides. The purposes of the present study were to characterize the variability associated with femoral rotational alignment techniques and to determine whether the use of a computer-assisted surgical navigation system reduced this variability. METHODS: Eleven orthopaedic surgeons used five alignment techniques (including one computer-assisted technique and four traditional techniques) to establish femoral rotational alignment axes on ten cadaveric specimens, and the orientation of these axes was recorded with use of a navigation system. These derived axes were compared against a reference transepicondylar axis on each femur that was established after complete dissection of all soft tissues. RESULTS: There was no difference between the mean errors of all five techniques (p > 0.11). Only 17% of the knees were rotated <5 degrees from the reference transepicondylar axis, with alignment errors ranging from 13 degrees of internal rotation to 16 degrees of external rotation. There were significant differences among the surgeons with regard to their ability to accurately establish femoral rotational alignment axes (p < 0.001). CONCLUSIONS: All techniques resulted in highly variable rotational alignment, with no technique being superior. This variability was primarily due to the particular surgeon who was performing the alignment procedure. A navigation system that relies on directly digitizing the femoral epicondyles to establish an alignment axis did not provide a more reliable means of establishing femoral rotational alignment than traditional techniques did.


Assuntos
Artroplastia do Joelho/efeitos adversos , Fêmur/cirurgia , Rotação , Cirurgia Assistida por Computador , Artroplastia do Joelho/métodos , Fenômenos Biomecânicos , Cadáver , Humanos , Prótese do Joelho , Técnicas Estereotáxicas
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