Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
HSS J ; 20(2): 214-221, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-39281985

RESUMO

Background: Mental health influences postoperative outcomes in orthopedic procedures. Increasing attention is being paid to this effect. Purpose: We sought to evaluate the effect of diagnosed depression, anxiety, or both on postoperative outcomes in patients who have undergone hip arthroscopy for femoroacetabular impingement syndrome (FAIS). Methods: We conducted a retrospective cohort study of 289 patients aged 30 years or younger who underwent hip arthroscopy for FAIS at a single institution from January 2014 to June 2021. Univariate statistics were used to assess differences between patients diagnosed with depression, anxiety, or both, and those without these diagnoses. Differences included demographics, operative characteristics, and postoperative outcomes: duration of postanesthesia care unit (PACU) stay, PACU pain scores, complications, reoperations, postoperative injections, 90-day emergency department (ED) visits, and patient-reported outcome measures (PROMs). Multivariate analysis was used to evaluate risk factors for postoperative complications, including wound infection, documented reinjury, postoperative intra-articular hip injection, and any reoperation. Results: Patients diagnosed with depression, anxiety, or both were more likely to be older, female, and have a higher comorbidity burden. At the time of surgery, they were more likely to undergo concomitant procedures, including bursectomy and iliotibial band release. Postoperatively, they had longer PACU stays (90.5 vs 75.1 minutes) and higher first PACU pain scores (5.9 vs 4.6), as well as higher rates of postoperative injection (18.1 vs 9.2%), any reoperation (13.9% vs 4.6%), and revision hip arthroscopy (11.1% vs. 3.7%). Diagnoses of depression, anxiety, or both were independently predictive of any reoperation (odds ratio [OR] = 2.841) and revision hip arthroscopy (OR = 3.401). Conclusion: This retrospective cohort study found that, in patients undergoing hip arthroscopy for FAIS, there was an association between a diagnosis of depression, anxiety, or both, and increased comorbidities, higher first PACU pain scores, longer PACU stays, and increased rates of postoperative injection, any reoperation, or revision hip arthroscopy. Targeted interventions may improve outcomes, but further study is warranted.

2.
Arch Orthop Trauma Surg ; 144(2): 823-829, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38103052

RESUMO

INTRODUCTION: Previous studies have shown that intra-articular hip injections prior to hip arthroscopy (HA) can be a helpful diagnostic tool. However, local anesthetic and corticosteroid injections can be chondrotoxic and corticosteroid injections have been shown to increase the risk of infection during subsequent surgical intervention. The purpose of this study was to evaluate whether preoperative injections adversely affect outcomes of HA using a national database. MATERIALS AND METHODS: The TriNetX database was retrospectively queried. Patients undergoing HA for femoroacetabular impingement with at least 1 year of claims runout were included in the analysis. Patients were grouped by whether they had a hip injection within 1 year prior to HA. The rates of repeat HA, total hip arthroplasty (THA), infection, osteonecrosis, and new onset hip OA at 1- and 5-years postoperatively were compared between groups. Statistical significance was assessed at α = 0.05. RESULTS: 6511 HA patients with previous injection and 1178 HA patients without previous injection were included. Patients with a previous injection were overall younger (32.3 vs. 34.7 years, p < 0.001), more likely to be female (69 vs. 48%, p < 0.001) and had a higher BMI (26.3 vs. 25.7 kg/m2, p = 0.043). At 1 and 5-years postoperatively, patients with any injection were 1.43 (p < 0.001) and 1.89 (p < 0.001) times more likely to undergo repeat HA, respectively. At 1 and 5-years postoperatively, patients who underwent a corticosteroid injection were 2.29 (p < 0.001) and 1.89 (p < 0.001) times more likely to undergo repeat HA than patients with local anesthetic injection only and 1.56 (p < 0.001) and 2.08 (p < 0.001) times more likely to undergo repeat HA than patients with no injection. CONCLUSIONS: Intraarticular hip injections prior to hip arthroscopy, particularly corticosteroid injections, are associated with increased risk of repeat hip arthroscopy at 1 and 5 years. Additional studies are needed to elucidate this risk.


Assuntos
Impacto Femoroacetabular , Articulação do Quadril , Humanos , Feminino , Masculino , Articulação do Quadril/cirurgia , Estudos Retrospectivos , Anestésicos Locais/efeitos adversos , Artroscopia/efeitos adversos , Impacto Femoroacetabular/cirurgia , Injeções Intra-Articulares/efeitos adversos , Corticosteroides/efeitos adversos , Resultado do Tratamento
3.
Shoulder Elbow ; 15(4 Suppl): 33-39, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37974601

RESUMO

Background: Re-tear following rotator cuff repair (RCR) is a concerning complication that can lead to poor patient outcomes and necessitate the need for revision surgery. The purpose of our study was to look at the combined construct of knotted vs. knotless medial row and suture vs. suture tape, focusing primarily on re-tear rates following surgery. Methods: A retrospective observational study of 343 consecutive patients undergoing arthroscopic double row, 4-anchor rotator cuff repair from February 2014 to March 2020 was conducted. Univariate and multivariate statistics were used to assess differences in demographics, comorbidities and tear characteristics between patients who experienced a symptomatic re-tear and those who did not. Results: The overall symptomatic re-tear rate was 7.6%. Patients who had a knotted medial row repair had a significantly lower rate of re-tear (4.7 vs. 11.3%, p = 0.022). Patients that had a knotted medial row and suture tape repair were significantly less likely to experience a re-tear (OR: 0.180, p = 0.001). Discussion: The use of suture tape and a knotted medial row repair decreases the incidence of symptomatic re-tear following rotator cuff repair. The combined construct of suture tape and a knotted medial row in rotator cuff repair decreases the risk for symptomatic re-tear following surgery.

4.
J Am Acad Orthop Surg ; 31(3): 148-154, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36473208

RESUMO

INTRODUCTION: Coronavirus disease 2019 (COVID-19) has resulted in a global pandemic with several hundred million infections worldwide. COVID-19 causes systemic complications that last beyond the initial infection. It is not known whether patients who undergo elective orthopaedic surgeries after COVID-19 are at increased risk of complications. The purpose of this study was to evaluate whether patients who undergo orthopaedic procedures after recent COVID-19 diagnosis are at increased risk of complications compared with those who have not had a recent COVID-19 diagnosis. METHODS: The TriNetX Research Network database was queried for patients undergoing elective orthopaedic surgeries from April 2020 to January 2022 in the following subspecialties: arthroscopic surgery, total joint arthroplasty, lumbar fusion, upper extremity surgery, foot and ankle (FA) surgery. Cohorts were defined by patients undergoing surgery with a diagnosis of COVID-19 from 7 to 90 days before surgery and those with no COVID-19 diagnosis 0 to 90 days before surgery. These cohorts were propensity-score matched based on differences in demographics and comorbidities. The matched cohorts were evaluated using measures of association analysis for complications, emergency department (ER) visits, and readmissions occurring 90 days postoperatively. RESULTS: Patients undergoing arthroscopic surgery were more likely to experience venous thromboembolism (VTE) ( P = 0.006), myocardial infarction ( P = 0.001), and ER visits ( P = 0.001). Patients undergoing total joint arthroplasty were more likely to experience VTE ( P < 0.001), myocardial infarction ( P < 0.001), pneumonia ( P < 0.001), and ER visits ( P = 0.037). Patients undergoing lumbar fusion were more likely to experience VTE ( P = 0.016), infection ( P < 0.001), pneumonia ( P < 0.001), and readmission ( P = 0.006). Patients undergoing upper extremity surgery were more likely to experience VTE ( P = 0.001) and pneumonia ( P = 0.015). Patients undergoing foot and ankle surgery were more likely to experience VTE ( P < 0.001) and pneumonia ( P < 0.001). CONCLUSION: There is an increased risk of complications in patients undergoing orthopaedic surgery after COVID-19 infection; all cohorts were at increased risk of VTE and most at increased risk of pneumonia. Additional investigation is needed to stratify the risk for individual patients.


Assuntos
COVID-19 , Infarto do Miocárdio , Tromboembolia Venosa , Humanos , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Estudos Retrospectivos , COVID-19/complicações , Artroscopia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Fatores de Risco
5.
JSES Int ; 6(6): 984-988, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36353422

RESUMO

Background: Rotator cuff repairs (RCRs) are one of the most commonly performed shoulder surgeries in the United States. Psychological health has been shown to influence postoperative outcomes in orthopedic procedures. The purpose of this study is to evaluate the relationship between depression and anxiety (DA) and psychotropic medication and postoperative outcomes following RCR. Methods: A single institution retrospective observational cohort study of 816 patients undergoing arthroscopic RCR from January 2014 to October 2020 was conducted. Univariate statistics were used to assess differences in demographics, operative characteristics, and postoperative outcomes; multivariate analysis was used to evaluate risk factors for postoperative complications. Results: Patients with DA were more likely to have a higher first (3.60 vs. 3.00, P = .004) and last (1.23 vs. 0.96, P = .042) postoperative pain scores, lower first (18.67 vs. 21.85, P = .008) and last (61.87 vs. 64.71, P = .014) Upper Extremity Functional Score (UEFS), more likely to experience an emergency department visit postoperatively (9.1 vs. 5.0%, P = .028), have a symptomatic recurrent tear (8.2 vs. 3.3%, P = .003), and persistent pain (4.3 vs. 1.2%, P = .011). After controlling for age, sex, body mass index, American Society of Anesthesiologists score, diabetes, smoking, coronary artery disease, asthma, hypertension, psychotropic medication and DA, having DA at the time of surgery was independently predictive of any complication (odds ratio, 2.033; P = .028) and persistent pain (odds ratio, 8.232; P ≤ .001). Patients with and without DA showed significant improvement in postoperative pain and UEFS from the first to the last measurement (P < .001). Conclusion: DA is not a deterrent for RCR but targeted interventions may be needed to decrease the occurrence of complications.

6.
J Orthop ; 30: 103-107, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35250198

RESUMO

BACKGROUND: Disparities in access, utilization and outcomes exist throughout the healthcare system for minority groups, including racial and ethnic minorities; these disparities have wide-reaching implications for individuals as well as the healthcare system as a whole. This study will examine the impact of race on short and medium term outcomes for patients undergoing rotator cuff repair (RCR) using matched cohorts. METHODS: Patients undergoing arthroscopic rotator cuff repair from 2016 to 2018 were extracted from two national databases: the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) and TriNetX Research Network. Using the ACS-NSQIP database, univariate analysis was performed to identify differences in comorbidities between white and minority patients. Patients were propensity score matched based on significant differences between groups and 30-day postoperative outcomes were assessed. These comorbidities were then used to propensity score match white and minority patients in the TriNetX database and two-year postoperative outcomes were evaluated. RESULTS: Following propensity score matching, 3716 patients remained in each group from the ACS-NSQIP database and 4185 patients remained in each group from the TriNetX database. The OR time for minority patients was longer than white patient in the ACS-NSQIP database (92.2 vs. 87.6 min, p < .001). There was no difference in medium-term outcomes for repeat RCR, infection or frozen shoulder between white and minority patients in the TriNetX database. CONCLUSION: After propensity score matching the only significant short-term outcome between white and minority patients undergoing RCR was a difference in OR time; there were no differences in medium-term outcomes. This may indicate that the source of racial disparities is one of access to healthcare rather than an innate difference in the patients' outcomes. Further study is needed to elucidate this issue.

7.
J Hip Preserv Surg ; 8(3): 255-260, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35414951

RESUMO

Fascia iliaca nerve blockade (FIB) has been previously described as an effective technique for reducing postoperative pain and opioid consumption after hip arthroscopy for femoroacetabular impingement syndrome (FAIS). We hypothesize that an FIB will significantly reduce opioid consumption, pain scores and recovery time in our population. A retrospective observational study of 326 consecutive patients undergoing hip arthroscopy for FAIS at a single institution was performed. Patients were classified based on whether or not they received an FIB. Patient demographics, surgical details, medication details and 6-month postoperative outcomes were collected. The primary endpoint was the amount of narcotics required intraoperatively and in the postanesthesia care unit (PACU). Of the 326 patients included in the study, 37 received an FIB. No differences in sex, age or other surgical details were observed between groups. Patients receiving an FIB were more likely to receive celecoxib (P < 0.001), pregabalin (P = 0.001) and methocarbamol (P = 0.002). The FIB group received lower doses of narcotics intraoperatively (P = 0.001), postoperatively (P < 0.001) and in total (P < 0.001). The FIB group also self-reported lower first pain scores upon arrival to PACU (P = 0.001) and experienced shorter PACU recovery times (P < 0.001). After controlling for differences between groups, patients who received an FIB required significantly lower amounts of narcotics, had shorter PACU times and lower first PACU pain score than those who did not (P < 0.001). No differences in complication rates were noted between groups. The use of FIB resulted in lower pain scores, reduced recovery time and decreased early postoperative narcotic requirements for patients undergoing hip arthroscopy for femoroacetabular impingement. Further study is required to validate these findings and determine the optimal approach to regional analgesia in this patient population.

8.
J Am Acad Orthop Surg Glob Res Rev ; 4(12): e20.00100, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33332853

RESUMO

INTRODUCTION: Wide-awake local anesthesia no tourniquet (WALANT) presents a nonstandard anesthetic approach initially described for use in hand surgery that has gained interest and utilization across a variety of orthopaedic procedures. In response to operating room resource constraints imposed by the COVID-19 pandemic, our orthopaedic service rapidly adopted and expanded its use of WALANT. METHODS: A retrospective review of 16 consecutive cases performed by 7 surgeons was conducted. Patient demographics, surgical details, and perioperative outcomes were assessed. The primary end point was WALANT failure, defined as intraoperative conversion to general anesthesia. RESULTS: No instances of WALANT failure requiring conversion to general anesthesia occurred. In recovery, one patient (6%) required narcotics for pain control, and the average postoperative pain numeric rating scale was 0.6. The maximum pain score experienced was 4 in the patient requiring postoperative narcotics. The average time in recovery was 42 minutes and ranged from 8 to 118 minutes. CONCLUSION: The WALANT technique was safely and effectively used in 16 cases across multiple orthopaedic subspecialties, including three procedures not previously described in the literature. WALANT techniques hold promise for use in future disaster scenarios and should be evaluated for potential incorporation into routine orthopaedic surgical care.


Assuntos
Anestesia Local/métodos , COVID-19 , Salas Cirúrgicas/organização & administração , Procedimentos Ortopédicos , Adulto , Idoso , Anestésicos Locais/administração & dosagem , COVID-19/epidemiologia , Epinefrina/administração & dosagem , Feminino , Hemostáticos/administração & dosagem , Humanos , Lidocaína/administração & dosagem , Masculino , Pessoa de Meia-Idade , Entorpecentes/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , Vasoconstritores/administração & dosagem , Adulto Jovem
9.
J Orthop ; 22: 372-376, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32952329

RESUMO

OBJECTIVE: The addition of open subpectoral biceps tenodesis to arthroscopic shoulder surgery with interscalene block has been anecdotally observed to result in increased postoperative pain. This study aims to evaluate the impact of tenodesis on early postoperative pain and recovery. METHODS: A retrospective review of patients undergoing arthroscopic shoulder surgery with general anesthesia and interscalene block was conducted. RESULTS: Patients undergoing tenodesis experienced longer OR time, pain numeric rating scale (NRS), and consumed more morphine milligram equivalents (MME) in PACU. After controlling for confounding factors, tenodesis was significantly associated with increased opioid MME consumption in the PACU (ß = 1.045, p = .028) and last PACU pain NRS (ß = 0.541, p = .009). CONCLUSION: Overall, pain scores and narcotic consumption were low after surgery, making these differences potentially clinically insignificant. Further study is required to evaluate whether these trends are consistent among this population.

10.
Am J Orthop (Belle Mead NJ) ; 44(9): E317-25, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26372758

RESUMO

Although no long-term difference between arthroscopic and mini-open rotator cuff repairs has been documented, use of arthroscopic repair has exploded. We conducted a study to determine which repair technique medical professionals preferred for their own surgery and to analyze the perceptions shaping those opinions. A survey was emailed to selected professionals at our institution: attendings, residents, and allied health professionals; 84 (41, 20, and 23, respectively) responded. Irrespective of specialty or career length, almost half (39, 46%) preferred deferring the repair choice to their surgeon; the other 45 preferred arthroscopic (22, 26%), mini-open (19, 23%), open (2, 2%), or no (2, 2%) repair. Most agreed repairs were safe and fast but had no opinion about cost-effectiveness or which technique provided the best outcome. Significantly (P < .05) more respondents thought arthroscopic and mini-open repairs promoted quick healing, good cosmetic results, and patient satisfaction compared with open repair, but these repairs were also perceived as significantly (P < .05) harder to learn and more challenging than open repair. It is important for medical professionals to recognize these biases, especially given that many defer to the judgment of their medical peers.


Assuntos
Atitude do Pessoal de Saúde , Tomada de Decisão Clínica , Procedimentos Ortopédicos/métodos , Manguito Rotador/cirurgia , Humanos , Satisfação do Paciente , Lesões do Manguito Rotador , Cicatrização
11.
Knee Surg Sports Traumatol Arthrosc ; 22(6): 1404-14, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24271329

RESUMO

PURPOSE: In order for T2 mapping to become more clinically applicable, reproducible subregions and standardized T2 parameters must be defined. This study sought to: (1) define clinically relevant subregions of knee cartilage using bone landmarks identifiable on both MR images and during arthroscopy and (2) determine healthy T2 values and T2 texture parameters within these subregions. METHODS: Twenty-five asymptomatic volunteers (age 18-35) were evaluated with a sagittal T2 mapping sequence. Manual segmentation was performed by three raters, and cartilage was divided into twenty-one subregions modified from the International Cartilage Repair Society Articular Cartilage Mapping System. Mean T2 values and texture parameters (entropy, variance, contrast, homogeneity) were recorded for each subregion, and inter-rater and intra-rater reliability was assessed. RESULTS: The central regions of the condyles had significantly higher T2 values than the posterior regions (P < 0.05) and higher variance than the posterior region on the medial side (P < 0.001). The central trochlea had significantly greater T2 values than the anterior and posterior condyles. The central lateral plateau had lower T2 values, lower variance, higher homogeneity, and lower contrast than nearly all subregions in the tibia. The central patellar regions had higher entropy than the superior and inferior regions (each P ≤ 0.001). Repeatability was good to excellent for all subregions. CONCLUSION: Significant differences in mean T2 values and texture parameters were found between subregions in this carefully selected asymptomatic population, which suggest that there is normal variation of T2 values within the knee joint. The clinically relevant subregions were found to be robust as demonstrated by the overall high repeatability.


Assuntos
Cartilagem Articular/anatomia & histologia , Articulação do Joelho/anatomia & histologia , Imageamento por Ressonância Magnética , Adolescente , Adulto , Artroscopia , Cartilagem Articular/cirurgia , Feminino , Voluntários Saudáveis , Humanos , Articulação do Joelho/cirurgia , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
12.
Orthopedics ; 35(9): e1449-52, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22955419

RESUMO

This article describes a rare congenital abnormality of anterior and posterior C1 fusion failure presenting after an acute athletic injury to the fibrous nonunion. C1 congenital malformations are rare, occurring in approximately 2% of patients; even rarer are combined anterior and posterior arch malformations in the same patient. Posterior ring abnormalities are more common than anterior ring injuries (4.5:1, respectively). To the authors' knowledge, combined anterior and posterior ring congenital malformations with subsequent injury have not been previously described. In the current patient, a congenital failure of fusion of the anterior and posterior arches of C1 was identified. The anterior fibrous nonunion was injured while the patient played football, leading to transient neurologic injury and dysphagia from soft tissue swelling. The patient was initially diagnosed with an acute fracture at another facility; however, given advanced imaging, flexion and extension views, and a normal neurologic examination, the authors diagnosed a traumatized congenital defect. The injury healed with a short period of cervical collar immobilization and supportive measures. Such malformations are usually found incidentally, but they can be symptomatic after trauma. Images to distinguish these deficits can be difficult because the differences between chronic nonunions and congenital malformations are subtle. Surgery is rarely indicated for congenital malformations because they are often stable even after injury; however, they may predispose patients to neurologic injury in the future with high-risk activities. Because the current patient had an increased chance of future injury secondary to the lack of bone formation in the C1 vertebrae, he was restricted from participating in contact sports.


Assuntos
Atlas Cervical/anormalidades , Atlas Cervical/lesões , Futebol Americano/lesões , Imobilização/métodos , Traumatismos da Coluna Vertebral/reabilitação , Adolescente , Atlas Cervical/cirurgia , Humanos , Masculino , Resultado do Tratamento
13.
Geriatr Orthop Surg Rehabil ; 3(1): 3-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23569691

RESUMO

Our goal was to determine whether there were age-related differences in pain, opiate use, and opiate side effects after total hip or knee arthroplasty in patients 60 years old or older. We hypothesized that there would be no significant differences between age groups in (1) mean pain score, (2) opiate use after adjusting for pain, or (3) opiate side effects after adjusting for opiate use and pain score. We retrospectively reviewed the electronic and paper charts of all patients undergoing total joint replacements at our institution over 3 years who met the following criteria: (1) 60 years old or older, (2) primary single total knee or total hip replacement, and (3) no preoperative dementia. Preoperative, intraoperative, and postoperative course data were collected using a customized data entry process and database. We divided the patients into 2 age groups, those 60 to 79 years old and those 80 years old or older. Using a marginal model with the panel variable of postoperative day, we investigated the associations between age group and pain, age group and pain adjusting for opiate use, and age group and complications (respiratory depression, naloxone usage as a measure of respiratory arrest, delirium, constipation, and urinary retention) adjusting for opiate use (Xtgee, Stata10, Stata Corp. LP, College Station, Texas). Significance was set at P < .05. We found no significant difference in pain scores between groups, but the older group had significantly fewer opiates prescribed yet significantly more side effects, including delirium (odds ratio 4.2), than did the younger group, even after adjusting for opiate dose and pain score.

14.
J Shoulder Elbow Surg ; 20(2): 213-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21145757

RESUMO

HYPOTHESIS: Our hypothesis was that the autograft-augmented direct repair of torn triceps tendons would have strength superior than that of direct repair when compared to the strength of intact distal triceps tendons. MATERIALS AND METHODS: The strength of the intact distal triceps tendon in 8 unpaired, fresh frozen cadaver specimens was measured to tendon failure by uniaxial tension in the sagittal plane. The torn triceps tendons were then repaired by direct repair (sutures through drill holes) or an autograft-augmented direct repair. Each tendon repair was biomechanically tested to failure, and load to displacement curves and the site of tendon failure were recorded. Tendon strength after each repair was compared with that of the other repair technique and with that of the intact triceps tendon. Significance was set at P < .05. RESULTS: Average failure loads for intact, direct repair, and augmented repair tendons were 1741, 317, and 593 N, respectively; augmented repairs were significantly stronger than direct repairs. In the intact tendon, failure occurred at the insertion site through a tear at the bone tendon interface or through a small cortical avulsion. In the repaired tendons, all but 1 failure occurred through the suture; 1 augmented repair failed first at the tendon and then through the suture. DISCUSSION: There is a paucity of clinical data regarding the optimal repair for distal triceps avulsion. We found that triceps repair affords less strength than the intact tendon, but augmented repair was nearly twice as strong as that of direct repair. Augmented repair may allow earlier range of motion, weightbearing, and rehabilitation, theoretically decreasing complications associated with the procedure. CONCLUSIONS: Augmented triceps repair is superior to direct triceps repair for a distal triceps avulsion produced in a cadaver model.


Assuntos
Traumatismos dos Tendões/fisiopatologia , Traumatismos dos Tendões/cirurgia , Tendões/fisiologia , Tendões/cirurgia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Cadáver , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos , Técnicas de Sutura , Transplante Autólogo , Cicatrização
15.
J Mol Biol ; 332(4): 795-808, 2003 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-12972252

RESUMO

Although APP mutations associated with inherited forms of Alzheimer's disease (AD) are relatively rare, detailed studies of these mutations may prove critical for gaining important insights into the mechanism(s) and etiology of AD. Here, we present a detailed biophysical characterization of the structural properties of protofibrils formed by the Arctic variant (E22G) of amyloid-beta protein (Abeta40(ARC)) as well as the effect of Abeta40(WT) on the distribution of the protofibrillar species formed by Abeta40(ARC) by characterizing biologically relevant mixtures of both proteins that may mimic the situation in the heterozygous patients. These studies revealed that the Arctic mutation accelerates both Abeta oligomerization and fibrillogenesis in vitro. In addition, Abeta40(ARC) was observed to affect both the morphology and the size distribution of Abeta protofibrils. Electron microscopy examination of the protofibrils formed by Abeta40(ARC) revealed several morphologies, including: (1) relatively compact spherical particles roughly 4-5 nm in diameter; (2) annular pore-like protofibrils; (3) large spherical particles 18-25 nm in diameter; and (4) short filaments with chain-like morphology. Conversion of Abeta40(ARC) protofibrils to fibrils occurred more rapidly than protofibrils formed in mixed solutions of Abeta40(WT)/Abeta40(ARC), suggesting that co-incubation of Abeta40(ARC) with Abeta40(WT) leads to kinetic stabilization of Abeta40(ARC) protofibrils. An increase in the ratio of Abeta(WT)/Abeta(MUT(Arctic)), therefore, may result in the accumulation of potential neurotoxic protofibrils and acceleration of disease progression in familial Alzheimer's disease mutation carriers.


Assuntos
Peptídeos beta-Amiloides/química , Mutação , Fragmentos de Peptídeos/química , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/ultraestrutura , Animais , Humanos , Peso Molecular , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/ultraestrutura , Peptídeos/química , Peptídeos/genética , Peptídeos/metabolismo , Estrutura Quaternária de Proteína , Ultracentrifugação
16.
EMBO J ; 21(11): 2636-45, 2002 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-12032076

RESUMO

PA28 is a gamma-interferon-induced complex that associates with the 20S proteasome and stimulates breakdown of small peptides. Recent immunoprecipitation studies indicate that, in vivo, PA28 also exists in larger complexes that also contain the 19S particle, which is required for ATP-ubiquitin-dependent degradation of proteins. However, because of its lability, the structure and properties of this larger complex remain unclear. Here, we demonstrate that, in vitro, PA28 can associate with 'singly capped' 26S (i.e. 19S-20S) proteasomes. Electron microscopy of the resulting structures revealed one PA28 ring at one end of the 20S particle and a 19S complex at the other. These hybrid complexes show enhanced hydrolysis of small peptides, but no significant increase in rates of protein breakdown. Nevertheless, during breakdown of proteins, the complexes containing PA28alphabeta or PA28alpha generated a pattern of peptides different from those generated by 26S proteasomes, without altering mean product length. Presumably, this change in peptides produced accounts for the capacity of PA28 to enhance antigen presentation.


Assuntos
Cisteína Endopeptidases/metabolismo , Complexos Multienzimáticos/metabolismo , Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo , Proteínas/metabolismo , Sequência de Aminoácidos , Animais , Autoantígenos , Eletroforese em Gel de Poliacrilamida , Hidrólise , Fator de Crescimento Insulin-Like I/metabolismo , Cinética , Espectrometria de Massas , Camundongos , Microscopia Eletrônica , Dados de Sequência Molecular , Peptídeos/química , Complexo de Endopeptidases do Proteassoma , Ligação Proteica , Proteínas/química , Coelhos , Proteínas Recombinantes/química , Baço/metabolismo , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA