RESUMO
Aging is associated with impaired tissue regeneration. Stem cell number and function have been identified as potential culprits. We first demonstrate a direct correlation between stem cell number and time to bone fracture union in a human patient cohort. We then devised an animal model recapitulating this age-associated decline in bone healing and identified increased cellular senescence caused by a systemic and local proinflammatory environment as the major contributor to the decline in skeletal stem/progenitor cell (SSPC) number and function. Decoupling age-associated systemic inflammation from chronological aging by using transgenic Nfkb1KO mice, we determined that the elevated inflammatory environment, and not chronological age, was responsible for the decrease in SSPC number and function. By using a pharmacological approach inhibiting NF-κB activation, we demonstrate a functional rejuvenation of aged SSPCs with decreased senescence, increased SSPC number, and increased osteogenic function. Unbiased, whole-genome RNA sequencing confirmed the reversal of the aging phenotype. Finally, in an ectopic model of bone healing, we demonstrate a functional restoration of regenerative potential in aged SSPCs. These data identify aging-associated inflammation as the cause of SSPC dysfunction and provide mechanistic insights into its reversal.
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Envelhecimento/metabolismo , Consolidação da Fratura , Fraturas Ósseas/metabolismo , Osteogênese , Células-Tronco/metabolismo , Envelhecimento/genética , Envelhecimento/patologia , Animais , Feminino , Fraturas Ósseas/patologia , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Knockout , Subunidade p50 de NF-kappa B/genética , Subunidade p50 de NF-kappa B/metabolismo , Células-Tronco/patologiaRESUMO
BACKGROUND: The management of glenoid deformity during anatomic total shoulder arthroplasty remains controversial. In this study, we evaluate variable correction of glenoid deformity by eccentric reaming. We hypothesize that partial correction of modified Walch B/C-type glenoid deformities can achieve 75% bone-implant contact area (BICA) with a reduced vault perforation risk compared with complete correction. METHODS: Fifty shoulder computed tomographic scans with glenohumeral osteoarthritis were retrospectively evaluated. The Tornier BluePrint v2.1.5 software simulated 3 eccentric reaming scenarios including no, partial, and complete deformity correction. Each scenario was evaluated at 4 BICAs and using 3 implant fixation types. Three-dimensional surface representations were used to evaluate medialization and vault perforation. RESULTS: The patients had mean glenoid retroversion and inclination of 18.5° and 8.8°, respectively, and mean posterior humeral head subluxation of 76%. With 75% BICA, the 3 fixation types had glenoid vault perforation in 6%-26% and 26%-54% of cases for partial and complete glenoid deformity correction, respectively. The central and posterior-inferior implant components were most likely to perforate across all scenarios. DISCUSSION: Eccentric reaming for glenoid deformity correction increases the risk of vault perforation. Severe glenoid deformity required increased medialization to achieve 75% BICA. Pegged implants have increased chances of perforation compared with a keeled design; the central and posterior-inferior components were most likely to perforate during deformity correction. CONCLUSION: Partial deformity correction of modified Walch B/C-type glenoid deformities can achieve 75% BICA while reducing the risk of vault perforation compared with complete correction at the time of anatomic total shoulder arthroplasty.
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Artroplastia do Ombro , Osteoartrite/cirurgia , Escápula/cirurgia , Idoso , Feminino , Cavidade Glenoide/cirurgia , Humanos , Cabeça do Úmero/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Articulação do Ombro/cirurgia , Prótese de Ombro , Tomografia Computadorizada por Raios XRESUMO
CONTEXT: Major League Baseball (MLB) players are at risk of hook of hamate fractures. There is a paucity of data assessing the effect of a hook of hamate fracture on MLB players' future athletic performance. OBJECTIVE: To determine if MLB players who sustain hook of hamate fractures demonstrate decreased performance upon return to competition when compared with their performance before injury and that of their control-matched peers. DESIGN: Retrospective case-control design. SETTING: Retrospective database study. PARTICIPANTS: 18 MLB players who sustained hook of hamate fractures. METHODS: Data for 18 MLB players with hook of hamate fractures incurred over 26 seasons (1989-2014) were obtained from injury reports, press releases, and player profiles ( www.mlb.com and www.baseballreference.com ). Player age, position, number of years in the league, mechanism of injury, and treatment were recorded. Individual season statistics for the 2 seasons immediately prior to injury and the 2 seasons after injury for the main performance variable-Wins Above Replacement-were obtained. Eighteen controls matched by player position, age, and performance statistics were identified. A performance comparison of the cohorts was performed. MAIN OUTCOME MEASURES: Postinjury performance compared with preinjury performance and matched-controls. RESULTS: Mean age at the time of injury was 25.1 years with a mean of 4.4 seasons of MLB experience prior to injury. All injuries were sustained to their nondominant batting hand. All players underwent operative intervention. There was no significant change in Wins Above Replacement or isolated power when preinjury and postinjury performance were compared. When compared with matched-controls, no significant decline in performance in Wins Above Replacement the first season and second season after injury was found. CONCLUSION: MLB players sustaining hook of hamate fractures can reasonably expect to return to their preinjury performance levels following operative treatment.
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Traumatismos em Atletas/cirurgia , Desempenho Atlético , Beisebol/lesões , Fraturas Ósseas/cirurgia , Traumatismos do Punho/cirurgia , Adulto , Atletas , Estudos de Casos e Controles , Humanos , Masculino , Estudos Retrospectivos , Volta ao EsporteRESUMO
Purpose To investigate whether assessment of bone strength with quantitative computed tomography (CT) in combination with dual-energy x-ray absorptiometry (DXA) is cost-effective as a screening tool for osteoporosis in postmenopausal women. Materials and Methods A state-transition microsimulation model of osteoporosis for postmenopausal women aged 55 years or older was developed with a lifetime horizon and U.S. societal perspective. All model inputs were derived from published literature. Three strategies were compared: no screening, DXA with T score-dependent rescreening intervals, and a combination of DXA and quantitative CT with different intervals (3, 5, and 10 years) at different screening initiation ages (55-65 years). Oral bisphosphonate therapy was started if DXA hip T scores were less than or equal to -2.5, 10-year risk for hip fracture was greater than 3% (World Health Organization Fracture Risk Assessment Tool score, or FRAX), 10-year risk for major osteoporotic fracture was greater than 20% (FRAX), quantitative CT femur bone strength was less than 3000 N, or occurrence of first fracture (eg, hip, vertebral body, wrist). Outcome measures were incremental cost-effectiveness ratios (ICERs) in 2015 U.S. dollars per quality-adjusted life year (QALY) gained and number of fragility fractures. Probabilistic sensitivity analysis was also performed. Results The most cost-effective strategy was combined DXA and quantitative CT screening starting at age 55 with quantitative CT screening every 5 years (ICER, $2000 per QALY). With this strategy, 12.8% of postmenopausal women sustained hip fractures in their remaining life (no screening, 18.7%; DXA screening, 15.8%). The corresponding percentages of vertebral fractures for DXA and quantitative CT with a 5-year interval, was 7.5%; no screening, 11.1%; DXA screening, 9%; for wrist fractures, 14%, 17.8%, and 16.4%, respectively; for other fractures, 22.6%, 30.8%, and 27.3%, respectively. In probabilistic sensitivity analysis, DXA and quantitative CT at age 55 years with quantitative CT screening every 5 years was the best strategy in more than 90% of all 1000 simulations (for thresholds of $50 000 per QALY and $100 000 per QALY). Conclusion Combined assessment of bone strength and bone mineral density is a cost-effective strategy for osteoporosis screening in postmenopausal women and has the potential to prevent a substantial number of fragility fractures. © RSNA, 2017 Online supplemental material is available for this article.
Assuntos
Densidade Óssea , Análise Custo-Benefício , Programas de Rastreamento , Osteoporose Pós-Menopausa , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Programas de Rastreamento/economia , Programas de Rastreamento/métodos , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/diagnóstico , Osteoporose Pós-Menopausa/diagnóstico por imagem , Osteoporose Pós-Menopausa/economia , Osteoporose Pós-Menopausa/epidemiologia , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios XRESUMO
Purpose To describe a nonlinear finite element analysis method by using magnetic resonance (MR) images for the assessment of the mechanical competence of the hip and to demonstrate the reproducibility of the tool. Materials and Methods This prospective study received institutional review board approval and fully complied with HIPAA regulations for patient data. Written informed consent was obtained from all subjects. A nonlinear finite element analysis method was developed to estimate mechanical parameters that relate to hip fracture resistance by using MR images. Twenty-three women (mean age ± standard deviation, 61.7 years ± 13.8) were recruited from a single osteoporosis center. To thoroughly assess the reproducibility of the finite element method, three separate analyses were performed: a test-retest reproducibility analysis, where each of the first 13 subjects underwent MR imaging on three separate occasions to determine longitudinal variability, and an intra- and interoperator reproducibility analysis, where a single examination was performed in each of the next 10 subjects and four operators independently performed the analysis two times in each of the subjects. Reproducibility of parameters that reflect fracture resistance was assessed by using the intraclass correlation coefficient and the coefficient of variation. Results For test-retest reproducibility analysis and inter- and intraoperator analyses for proximal femur stiffness, yield strain, yield load, ultimate strain, ultimate load, resilience, and toughness in both stance and sideways-fall loading configurations each had an individual median coefficient of variation of less than 10%. Additionally, all measures had an intraclass correlation coefficient higher than 0.99. Conclusion This experiment demonstrates that the finite element analysis model can consistently and reliably provide fracture risk information on correctly segmented bone images. © RSNA, 2016 Online supplemental material is available for this article.
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Análise de Elementos Finitos , Fraturas do Quadril/diagnóstico por imagem , Imageamento por Ressonância Magnética , Fenômenos Biomecânicos , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos TestesRESUMO
During the previous 2 decades, numerous surgical procedures have become available to treat osteochondral lesions of the talus. The objective of the present study was to use 7 Tesla (7T) magnetic resonance imaging (MRI) to quantify and compare T2 values (a marker of collagen architecture) of native tibiotalar cartilage and cartilage repair tissue in patients treated with a juvenile particulate allograft for osteochondral lesions of the talus. The institutional review board approved the present study, and all subjects provided written informed consent. We scanned the ankles of 7 cartilage repair patients using a 7T MRI scanner with a multi-echo spin-echo sequence to measure the cartilage T2 values. We assessed the cartilage T2 values in the talar repair tissue, adjacent native talar cartilage, and overlying tibial cartilage. We compared the differences between groups using the paired t test. The talar cartilage repair tissue demonstrated greater mean T2 relaxation times compared with the native adjacent talar cartilage (64.88 ± 12.23 ms versus 49.56 ± 7.82 ms; p = .043). The tibial cartilage regions overlying these talar cartilage regions demonstrated a trend toward greater T2 relaxation times (77.00 ± 31.29 ms versus 59.52 ± 7.89 ms; p = .067). 7T MRI can detect differences in T2 values in cartilage repair tissue compared with native cartilage and could be useful for monitoring the status of cartilage health after surgical intervention.
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Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/cirurgia , Imagem Ecoplanar/métodos , Tálus/cirurgia , Transplante de Tecidos/métodos , Adulto , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Cartilagem Articular/patologia , Estudos de Viabilidade , Feminino , Seguimentos , Sobrevivência de Enxerto , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Osteocondrite/diagnóstico por imagem , Osteocondrite/cirurgia , Estudos Retrospectivos , Fatores de Risco , Estudos de Amostragem , Tálus/diagnóstico por imagem , Tálus/patologia , Transplante Homólogo/métodos , Resultado do TratamentoRESUMO
Automating the process of femoroacetabular cartilage identification from magnetic resonance imaging (MRI) images has important implications to guiding clinical care by providing a temporal metric that allows for optimizing the timing for joint preservation surgery. In this paper, we evaluate a new automated cartilage segmentation method using a time trial, segmented volume comparison, overlap metrics, and Euclidean distance mapping. We report interrater overlap metrics using the true fast imaging with steady-state precession MRI sequence of 0.874, 0.546, and 0.704 for the total overlap, union overlap, and mean overlap, respectively. This method was 3.28× faster than manual segmentation. This technique provides clinicians with volumetric cartilage information that is useful for optimizing the timing for joint preservation procedures.
Assuntos
Cartilagem Articular/cirurgia , Quadril/cirurgia , Adulto , Idoso , Algoritmos , Automação , Cartilagem Articular/patologia , Reações Falso-Positivas , Feminino , Articulação do Quadril/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Computed tomography pulmonary angiography (CTA) is the gold standard for diagnosing pulmonary embolism (PE) but involves radiation and iodinated contrast exposure. Of orthopedic patients evaluated for PE, a minority have a positive CTA study. Herein, we evaluate end tidal carbon dioxide (ETCO2) as a method to identify patients at low risk for PE and may not require a CTA. We hypothesize that ETCO2 will be useful for predicting the absence of PE in postoperative orthopedic patients. METHODS: In this prospective study, all patients older than 18 years who were admitted for orthopedic surgery and who had a CTA performed for PE were eligible. These patients underwent an ETCO2 measurement. Patients were determined to have PE if they had a positive PE-protocol CT. RESULTS: Between May 2014 and April 2015, 121 patients met the inclusion criteria for the study. Of these patients, 84 had a negative CTA examination, 25 had a positive examination, and 12 had a nondiagnostic examination. We found a statistically significant difference (P = .03) when comparing the average ETCO2 values for the positive and negative CTA groups. An ETCO2 cutoff value of 43 mm Hg was 100% sensitive with a negative predictive value of 100% for absence of PE on CTA. CONCLUSION: This study demonstrates a significant difference in ETCO2 measurements between postoperative orthopedic patients with and without CTA-detected PE. A cutoff value of >43 mm Hg may be useful in excluding patients from undergoing CTA.
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Dióxido de Carbono/análise , Programas de Rastreamento/métodos , Procedimentos Ortopédicos/efeitos adversos , Embolia Pulmonar/diagnóstico , Idoso , Angiografia , Testes Respiratórios , Angiografia por Tomografia Computadorizada , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ortopedia , Período Pós-Operatório , Estudos Prospectivos , Embolia Pulmonar/etiologiaRESUMO
There is increasing use of three-dimensional (3D) computed tomography (CT) for researching anterior cruciate ligament (ACL) reconstructions and tunnel placement. However, there is limited 3D CT data on the ACL footprint. The purpose of this study is to define the native ACL femoral footprint using 3D surface reconstructions of computed tomography (CT) imaging of cadaveric knees. The femoral insertion of the ACL was meticulously dissected and marked with drill holes in seven cadaveric knees. CT scans were performed on each specimen, and 3D computer models were created. Distance from the condyle edges to the margins of the footprint were referenced to the total condylar size. This was performed both parallel and perpendicular to the femoral axis as well as the intercondylar notch. The mean condylar depth (c/C) ratios along the axis of the femur were 0.45 ± 0.06 for the anterior border, 0.44 ± 0.08 for the posterior border, 0.26 ± 0.07 for the proximal border, and 0.63 ± 0.08 for the distal border. The mean notch (n/N) ratios for the four margins were 0.37 ± 0.04 for the anterior border, 0.67 ± 0.08 for the posterior border, 0.49 ± 0.07 for the proximal margin, and 0.50 ± 0.06 for the distal border. The mean c/C ratios parallel the intercondylar notch measured 0.23 ± 0.03 for the anterior border, 0.27 ± 0.04 for the posterior border, 0.37 ± 0.04 for the proximal border, and 0.12 ± 0.02 for the distal border. The mean n/N ratios perpendicular to the intercondylar notch measured 0.11 ± 0.06 for the anterior border, 0.52 ± 0.09 the posterior border, 0.29 ± 0.06 for the proximal border, and 0.30 ± 0.06 for the distal border. This study provides reference measures of the femoral footprint of the ACL using 3D CT. It will assist future studies that use advanced imaging to evaluate accuracy of ACL reconstruction.
Assuntos
Ligamento Cruzado Anterior/anatomia & histologia , Fêmur/anatomia & histologia , Fêmur/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Tomografia Computadorizada por Raios XRESUMO
PURPOSE: The purpose of this study was to define an anatomic standard for the femoral footprint of the posterior cruciate ligament (PCL) based on 3-dimensional (3D) surface reconstructions of computed tomography (CT) scans of cadaveric knees. METHODS: The femoral insertion of the PCL was identified and marked with drill holes in 7 cadaveric knees. CT scans were performed on each specimen, and 3D computer models were generated. The distance from the condyle edges to the margins of the footprint were referenced to the total condylar size parallel and perpendicular to the femoral axis and intercondylar notch. RESULTS: The mean ratio of the anteroposterior width of the medial femoral condyle referenced parallel to the intercondylar notch measured 0.08 ± 0.02 for the anterior border, 0.60 ± 0.08 for the posterior border, 0.16 ± 0.05 for the proximal border, and 0.44 ± 0.06 for the distal border. The mean ratio of the superior-inferior height of the medial femoral condyle with respect to the apex of the intercondylar notch corrected and referenced perpendicular to the intercondylar notch measured 0.14 ± 0.04 for the anterior border, 0.44 ± 0.07 for the posterior border, 0.03 ± 0.02 for the proximal border, and 0.56 ± 0.07 for the distal border. CONCLUSIONS: This cadaveric study provides an anatomic reference for mathematical analysis of the femoral PCL footprint using CT-based 3D topographic modeling. The average PCL center point is located 25% down from the roof of the notch and 38% from anterior to posterior from the anterior condyle with regard to total medial femoral condyle length. CLINICAL RELEVANCE: This study provides a standard of measurement for future studies that use advanced imaging to evaluate the accuracy of PCL reconstruction.
Assuntos
Fêmur/anatomia & histologia , Fêmur/diagnóstico por imagem , Imageamento Tridimensional/métodos , Ligamento Cruzado Posterior/anatomia & histologia , Ligamento Cruzado Posterior/diagnóstico por imagem , Cadáver , Humanos , Processamento de Imagem Assistida por Computador , Técnicas In Vitro , Tomografia Computadorizada por Raios XRESUMO
PURPOSE: To evaluate the interobserver and intraobserver reliability of radiographic assessment of tunnel placement in anterior cruciate ligament reconstruction. METHODS: Seven sports fellowship-trained orthopaedic surgeons in the Multicenter Orthopaedic Outcomes Network (MOON) group participated in the study. We prospectively enrolled 54 consecutive patients after primary anterior cruciate ligament reconstruction. Postoperative plain radiographs were obtained including a full-extension anteroposterior view of the knee, a lateral view of the knee in full extension, and a notch view at 45° of flexion (Rosenberg view). Three blinded reviewers performed 8 different radiographic measurements including those of Harner and Aglietti/Jonsson. Intraclass correlation coefficients were used to determine reliability of the measurements. Intrarater reliability was assessed by repeated measurements of a subset of 20 patient images from 1 institution, and inter-rater reliability was assessed by use of all 54 sets of films from a total of 4 institutions. RESULTS: Intraobserver reliability for femoral measures ranged from none to substantial, with notch height having the worst results. Intraobserver reliability was moderate to almost perfect for tibial measures. Interobserver reliability ranged from slight to moderate for femoral measures. The Harner method for determining tunnel depth was more reliable than the Aglietti/Jonsson method. Interobserver reliability for tibial measures ranged from fair to substantial. The presence of metal interference screws did not improve reliability of measurements. CONCLUSIONS: Postoperative radiographs are easily obtained, but our results show that radiographic measurements are of quite variable reliability, with most of the results falling into the fair to moderate categories.
Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Artrografia , Traumatismos do Joelho/cirurgia , Articulação do Joelho/diagnóstico por imagem , Cuidados Pós-Operatórios , Ligamento Cruzado Anterior/diagnóstico por imagem , Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Reconstrução do Ligamento Cruzado Anterior/normas , Humanos , Traumatismos do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Variações Dependentes do Observador , Estudos Prospectivos , Reprodutibilidade dos Testes , Método Simples-Cego , Resultado do TratamentoRESUMO
STUDY DESIGN: A retrospective case review combined with a review of current literature. OBJECTIVES: We describe a case of antineutrophil cytoplasmic antibodies (ANCA)-related systemic vasculitis, with nearly 4 years of clinical and radiographic follow-up, initially presenting as hypertrophic spinal pachymeningitis (HSP). The diagnosis, surgical, and medical treatment of HSP are discussed in the context of a literature review. SUMMARY OF BACKGROUND DATA: HSP is a rare disease characterized by hypertrophic inflammation of the dura mater and clinical symptoms that progress from local pain to myelopathy. HSP has been associated with infectious, inflammatory, autoimmune, and traumatic conditions. Surgical decompression and/or corticosteroid therapy have been shown effective at managing this disorder, but identifying associated diseases can be essential to a favorable patient outcome. METHODS: The medical, pathologic, and radiographic records of this case were reviewed. A computer-based search of the PubMed database was used to perform a comprehensive literature review of HSP. RESULTS: We report a 66-year-old male with a history of renal cell carcinoma and bladder cancer who presented with upper abdominal pain, thoracic myelopathy (progressive weakness and numbness of the lower extremities, and gait disturbances), and weight loss. A diagnosis of HSP was subsequently shown to be the initial presentation of ANCA-related systemic vasculitis. CONCLUSIONS: The possibility of an ANCA-related systemic vasculitis presenting as HSP without systemic signs is a diagnostic and therapeutic challenge for the spinal surgeon. The diagnosis of HSP should initiate a search for an associated disease process and close follow-up after initial treatment. With interdisciplinary collaboration between medicine, radiology, pathology, and orthopedics, the diagnosis was made and a treatment initiated which halted disease progression and has maintained remission for more than 4 years.
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Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/cirurgia , Meningite/etiologia , Meningite/cirurgia , Doenças da Medula Espinal/etiologia , Doenças da Medula Espinal/cirurgia , Idoso , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Diagnóstico Diferencial , Humanos , Masculino , Meningite/diagnóstico , Radiografia , Doenças da Medula Espinal/diagnóstico , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/patologia , Resultado do TratamentoRESUMO
OBJECTIVE: The purpose of this study was to determine if differences in Wiberg classification play a role in the ability of donor patellar osteochondral allografts to match the native patellar surface when treating osteochondral defects of the patellar apex. DESIGN: Twenty (10 Wiberg I and 10 Wiberg II/III) human patellae were designated as the recipient. Each recipient was size-matched to both a Wiberg I and a Wiberg II/III patellar donor. A 16-mm circular osteochondral "defect" was created on the central ridge of the recipient patella. The randomly ordered donor Wiberg I or Wiberg II/III plug was harvested from a homologous location and transplanted into the recipient. The recipient was then nano-CT (computed tomography) scanned, digitally reconstructed, registered to the initial nano-CT scan of the recipient patella, and processed to determine root mean squared circumferential step-off heights as well as surface height deviation. The process was then repeated for the other allograft plug. RESULTS: There was no significant difference in mean step-off height between matched and unmatched Wiberg plugs; however, there was a statistically significant difference in surface height deviation over the whole surface (0.50 mm and 0.64 mm respectively, P = 0.03). This difference of 0.14 mm is not felt to be clinically significant. Tibial width was correlated to patellar width (r = 0.82) and patellar height (r = 0.68). CONCLUSIONS: For osteochondral allograft sizes up to 16 mm there appears to be no advantage to match donor and recipient patellar morphology. Further study is warranted to evaluate defects requiring larger graft sizes.
Assuntos
Fraturas Intra-Articulares , Patela , Aloenxertos , Humanos , Patela/diagnóstico por imagem , Patela/cirurgia , Tomografia Computadorizada por Raios X , Transplante HomólogoRESUMO
The level of financial literacy varies among orthopaedic trainees. Personal finance ideally should be taught before accepting student loans; however, when this has not happened, it is imperative that trainees start taking their personal finances seriously. Many trainees are faced with large amounts of student debt and struggle with how to manage a large salary increase in their first job. This can lead to poor financial decisions including insufficient savings. The authors provide a comprehensive viewpoint on personal finance for the orthopaedic trainee. In this article, we provide future orthopaedic surgeons with a framework for personal financial management as a starting point to understanding the financial concepts of budgeting, investment, debt management, mortgage, disability insurance, and life insurance.
RESUMO
Nonbiologic medications (local anesthetics, corticosteroids, and nonsteroidal anti-inflammatory drugs) are commonly administered to athletes for analgesia after injury. However, the risks of nonbiologic injections often are overlooked simply because of their long-term market availability. A thorough understanding of the mechanism of action, the reported benefits, and the potential risks of nonbiologic medications is crucial prior to their use, especially in the treatment of young athletes. Sports medicine physicians and surgeons must be aware of the systemic and local effects of these medications to ensure an appropriate drug choice that minimizes side effects and avoids recently reported toxicity to myocytes, tenocytes, and chondrocytes.
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Corticosteroides/administração & dosagem , Anestésicos Locais/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Medicina Esportiva/métodos , Atletas , Humanos , InjeçõesRESUMO
Systems engineering is an interdisciplinary approach to creating, evaluating, and managing a complex process in order to increase reliability, cost-effectiveness, and quality. The operating room is a complex environment that requires human-human interaction, human-device interaction, planning, and coordination of scarce resources for the purpose of providing surgery to patients in a safe and efficient manner. The operating room is an important revenue generator, but it can also be responsible for unsustainable costs if not managed effectively. Reducing costs and increasing the efficiency of surgical cases is important for generating health care value. Efficiency efforts that aim for standardization of surgical protocols must be balanced by flexibility in the unpredictable operating room environment. This paper reviews systems engineering efforts to improve efficiency in the operating room including operating room scheduling, personnel factors, resource management, orthopedicspecific initiatives, and future innovations.
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Eficiência Organizacional , Modelos Organizacionais , Doenças Musculoesqueléticas/cirurgia , Salas Cirúrgicas/organização & administração , Análise de Sistemas , Agendamento de Consultas , Análise Custo-Benefício , Humanos , Técnicas de Planejamento , Melhoria de Qualidade , Alocação de RecursosRESUMO
BACKGROUND: The competitive environment of athletics has promoted the exploration of any technology application that may offer an edge with performance and recovery from injury. Ischemic therapy is one such technology that has rapidly been incorporated into training rooms and physical therapy clinics worldwide. This therapy modality is reported to increase an athlete's ability to improve muscle mass, strength, and endurance. PURPOSE: To provide the sports medicine physician with an understanding of the current state of ischemic therapy technology, including treatment specifications, known physiological effects, hypothesized mechanisms, biochemical effects, athletic applications, medical applications, animal models, and future research recommendations. STUDY DESIGN: Literature review. METHODS: A computer-based search of the PubMed database was used to perform a comprehensive literature review on musculoskeletal ischemic therapy. RESULTS: The current research on ischemic therapy is largely composed of case series with varying equipment, methods, and therapy specifications. The publication of case series has value in identifying this technology for future research, but the results of these studies should not be justification for application to athletes without validation of safety and effectiveness. CONCLUSION: To date, ischemic therapy remains unvalidated, and the mechanism by which it improves muscle performance is not clear.
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Precondicionamento Isquêmico , Músculo Esquelético/irrigação sanguínea , Medicina Esportiva , Animais , Constrição , HumanosRESUMO
The purpose of this study is to analyze trends in the epidemiology of paediatric stress fractures. The New York Statewide Planning and Research Cooperative System database was queried for stress fractures in children between the ages of 6 and 18 years. After checking for monotonicity of the data, Spearman's correlation coefficient was calculated. Multivariate regressions were used to test for associations between demographic variables and risk of stress fracture. Analysis of 11 475 386 outpatient visits between 2000 and 2015 showed that the annual incidence of paediatric stress fractures increased from 1.37 cases per 100 000 outpatient visits in 2006 to 5.32 per 100 000 visits in 2015 (ρ = 0.876, P < 0.01). The mean age at the time of injury was 14.4 ± 2.8 years. Children younger than 14 years accounted for 33.6% of the cohort. Age, male sex, white ethnicity, and private insurance were statistically significant predictors of stress fractures in a multivariate model. This study is the first to document an increase in the annual incidence of paediatric stress fractures.
Assuntos
Fraturas de Estresse/epidemiologia , Adolescente , Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/etiologia , Criança , Estudos de Coortes , Bases de Dados Factuais , Feminino , Fraturas de Estresse/etiologia , Humanos , Incidência , Masculino , New York/epidemiologiaRESUMO
BACKGROUND: Blood flow restriction therapy (BFRT) has been increasingly applied to improve athletic performance and injury recovery. Validation of BFRT has lagged behind commercialization, and currently the mechanism by which this therapy acts is unknown. BFRT is one type of ischemic therapy, which involves exercising with blood flow restriction. Repetitive restriction of muscle blood flow (RRMBF) is another ischemic therapy type, which does not include exercise. HYPOTHESIS/PURPOSE: The purpose was to develop a rat model of ischemic therapy, characterize changes to muscle contractility, and evaluate local and systemic biochemical and histologic responses of 2 ischemic therapy types. We hypothesized that ischemic therapy would improve muscle mass and strength as compared with the control group. STUDY DESIGN: Controlled laboratory study. METHODS: Four groups of 10 Sprague-Dawley rats were established: control, stimulation, RRMBF, and BFRT. One hindlimb of each subject underwent 8 treatment sessions over 4 weeks. To simulate exercise, the stimulation group underwent peroneal nerve stimulation for 2 minutes. The RRMBF group used a pneumatic cuff inflated to 100 mm Hg with a 48-minute protocol. The BFRT group involved 100-mm Hg pneumatic cuff inflation and peroneal nerve stimulation for a 5-minute protocol. Four methods of evaluation were performed: in vivo contractility testing, histology, immunohistochemistry, and ELISA. Analysis of variance with post hoc Tukey test and linear mixed effects modeling were used to compare the treatment groups. RESULTS: There was no difference in muscle mass among groups (P = .40) or between hindlimbs (P = .73). In vivo contractility testing showed no difference in maximum contractile force among groups (P = .64) or between hindlimbs (P = .30). On histology, myocyte cross-sectional area was not different among groups (P = .55) or between hindlimbs (P = .44). Pax7 immunohistochemistry demonstrated no difference in muscle satellite cell density among groups (P = .06) or between hindlimbs (P = .046). ELISA demonstrated the RRMBF group as eliciting elevated GH levels as compared with the other groups (P < .001). CONCLUSION: Ischemic therapy did not induce gains in muscle mass, contractility strength, fiber cross-sectional area, or satellite cell density locally or systemically in this model, although the RRMBF group did have elevated GH levels on ELISA. CLINICAL RELEVANCE: This animal model does not support ischemic therapy as a method to improve muscle mass, function, or satellite cell density.
Assuntos
Extremidade Inferior , Contração Muscular , Músculo Esquelético/irrigação sanguínea , Fluxo Sanguíneo Regional , Animais , Membro Posterior , Modelos Animais , Ratos , Ratos Sprague-DawleyRESUMO
Medical imaging technologies have allowed for in vivo exploration and evaluation of the human musculoskeletal system. Three-dimensional bone models generated using image-segmentation techniques provide a means to optimize individualized orthopedic surgical procedures using engineering analyses. However, many of the current segmentation techniques are not clinically practical due to the required time and human intervention. As a proof of concept, we demonstrate the use of an expectation maximization (EM) algorithm to segment the hand phalanx bones, and hypothesize that this semi-automated technique will improve the efficiency while providing similar definitions as compared to a manual rater. Our results show a relative overlap of the proximal, middle, and distal phalanx bones of 0.83, 0.79, and 0.72 for the EM technique when compared to validated manual segmentations. The EM segmentations were also compared to 3D surface scans of the cadaveric specimens, which resulted in distance maps showing an average distance for the proximal, middle, and distal phalanx bones of 0.45, 0.46, and 0.51 mm, respectively. The EM segmentation improved on the segmentation speed of the manual techniques by a factor of eight. Overall, the manual segmentations had greater relative overlap metric values, which suggests that the manual segmentations are a better fit to the actual surface of the bone. As shown by the comparison to the bone surface scans, the EM technique provides a similar representation of the anatomic structure and offers an increase in efficiency that could help to reduce the time needed for defining anatomical structures from CT scans.