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1.
Sports Health ; 13(1): 13-14, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33302808
2.
Sports Health ; : 1941738120955184, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33337984

RESUMO

BACKGROUND: Thigh muscle weakness after anterior cruciate ligament reconstruction (ACLR) can persist after returning to activity. While resistance training can improve muscle function, "nonfunctional" training methods are not optimal for inducing transfer of benefits to activities such as walking. Here, we tested the feasibility of a novel functional resistance training (FRT) approach to restore strength and function in an individual with ACLR. HYPOTHESIS: FRT would improve knee strength and function after ACLR. STUDY DESIGN: Case report. LEVEL OF EVIDENCE: Level 5. METHODS: A 15-year-old male patient volunteered for an 8-week intervention where he performed 30 minutes of treadmill walking, 3 times per week, while wearing a custom-designed knee brace that provided resistance to the thigh muscles of his ACLR leg. Thigh strength, gait mechanics, and corticospinal and spinal excitability were assessed before and immediately after the 8-week intervention. Voluntary muscle activation was evaluated immediately after the intervention. RESULTS: Knee extensor and flexor strength increased in the ACLR leg from pre- to posttraining (130 to 225 N·m [+74%] and 44 to 88 N·m [+99%], respectively) and increases in between-limb extensor and flexor strength symmetry (45% to 92% [+74%] and 47% to 72% [+65%], respectively) were also noted. After the intervention, voluntary muscle activation in the ACLR leg was 72%, compared with the non-ACLR leg at 75%. Knee angle and moment during late stance phase decreased (ie, improved) in the ACLR leg and appeared more similar to the non-ACLR leg after FRT training (18° to 14° [-23.4] and 0.07 to -0.02 N·m·kg-1·m-1 [-122.8%], respectively). Corticospinal and spinal excitability in the ACLR leg decreased (3511 to 2511 [-28.5%] and 0.42 to 0.24 [-43.7%], respectively) from pre- to posttraining. CONCLUSION: A full 8 weeks of FRT that targeted both quadriceps and hamstring muscles lead to improvements in strength and gait, suggesting that FRT may constitute a promising and practical alternative to traditional methods of resistance training. CLINICAL RELEVANCE: FRT may serve as a viable approach to improve knee strength and function after ACL reconstruction.

3.
Sports Health ; 12(6): 516-517, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33106128
4.
Sports Health ; 12(5): 423-424, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32854578
5.
JBMR Plus ; 4(8): e10377, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32803109

RESUMO

Sclerostin antibody (SclAb) therapy has been suggested as a novel therapeutic approach toward addressing the fragility phenotypic of osteogenesis imperfecta (OI). Observations of cellular and transcriptional responses to SclAb in OI have been limited to mouse models of the disorder, leaving a paucity of data on the human OI osteoblastic cellular response to the treatment. Here, we explore factors associated with response to SclAb therapy in vitro and in a novel xenograft model using OI bone tissue derived from pediatric patients. Bone isolates (approximately 2 mm3) from OI patients (OI type III, type III/IV, and type IV, n = 7; non-OI control, n = 5) were collected to media, randomly assigned to an untreated (UN), low-dose SclAb (TRL, 2.5 µg/mL), or high-dose SclAb (TRH, 25 µg/mL) group, and maintained in vitro at 37°C. Treatment occurred on days 2 and 4 and was removed on day 5 for TaqMan qPCR analysis of genes related to the Wnt pathway. A subset of bone was implanted s.c. into an athymic mouse, representing our xenograft model, and treated (25 mg/kg s.c. 2×/week for 2/4 weeks). Implanted OI bone was evaluated using µCT and histomorphometry. Expression of Wnt/Wnt-related targets varied among untreated OI bone isolates. When treated with SclAb, OI bone showed an upregulation in osteoblast and osteoblast progenitor markers, which was heterogeneous across tissue. Interestingly, the greatest magnitude of response generally corresponded to samples with low untreated expression of progenitor markers. Conversely, samples with high untreated expression of these markers showed a lower response to treatment. in vivo implanted OI bone showed a bone-forming response to SclAb via µCT, which was corroborated by histomorphometry. SclAb induced downstream Wnt targets WISP1 and TWIST1, and elicited a compensatory response in Wnt inhibitors SOST and DKK1 in OI bone with the greatest magnitude from OI cortical bone. Understanding patients' genetic, cellular, and morphological bone phenotypes may play an important role in predicting treatment response. This information may aid in clinical decision-making for pharmacological interventions designed to address fragility in OI. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

6.
J Exp Orthop ; 7(1): 57, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32720234

RESUMO

ESSKA is constantly committed to promoting the improvement of scientific quality through the publication of books and the organization of dedicated conferences. In line with this commitment, this interview paper was crated with the aim of being useful for all the young scientists and orthopaedics keen in musculoskeletal and sport medicine research. Three Editors from the most important journals in our field were invited to participate: Jon Karlsson from Knee Surgery Sport Traumatology and Arthroscopy, Bruce Reider from The American Journal of Sport Medicine and Edward Wojtys from Sports Health.

7.
Sports Health ; 12(4): 326, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32602819
8.
Sports Health ; 12(4): 325, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525453
9.
Am J Sports Med ; 48(9): 2287-2294, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32485114

RESUMO

BACKGROUND: Lower extremity injuries are the most common injuries in professional sports and carry a high burden to players and teams in the National Football League (NFL). Injury prevention strategies can be refined by a foundational understanding of the occurrence and effect of these injuries on NFL players. PURPOSE: To determine the incidence of specific lower extremity injuries sustained by NFL players across 4 NFL seasons. STUDY DESIGN: Descriptive epidemiology study. METHODS: This retrospective, observational study included all time-loss lower extremity injuries that occurred during football-related activities during the 2015 through 2018 seasons. Injury data were collected prospectively through a leaguewide electronic health record (EHR) system and linked with NFL game statistics and player participation to calculate injury incidence per season and per 10,000 player-plays for lower extremity injuries overall and for specific injuries. Days lost due to injury were estimated through 2018 for injuries occurring in the 2015 to 2017 seasons. RESULTS: An average of 2006 time-loss lower extremity injuries were reported each season over this 4-year study, representing a 1-season risk of 41% for an NFL player. Incidence was stable from 2015 to 2018, with an estimated total missed time burden each NFL season of approximately 56,700 player-days lost. Most (58.7%) of these injuries occurred during games, with an overall higher rate of injuries observed in preseason compared with regular season (11.5 vs 9.4 injuries per 10,000 player-plays in games). The knee was the most commonly injured lower extremity region (29.3% of lower body injuries), followed by the ankle (22.4%), thigh (17.2%), and foot (9.1%). Hamstring strains were the most common lower extremity injury, followed by lateral ankle sprains, adductor strains, high ankle sprains, and medial collateral ligament tears. CONCLUSION: Lower extremity injuries affect a high number of NFL players, and the incidence did not decrease over the 4 seasons studied. Prevention and rehabilitation protocols for these injuries should continue to be prioritized.


Assuntos
Traumatismos em Atletas/epidemiologia , Futebol Americano/lesões , Extremidade Inferior/lesões , Humanos , Incidência , Ligamentos/lesões , Músculo Esquelético/lesões , Estudos Retrospectivos , Ruptura/epidemiologia , Entorses e Distensões/epidemiologia
10.
Sports Health ; 12(2): 114-115, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392087
11.
Sports Health ; 12(3): 219-220, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32340591
12.
Am J Sports Med ; 48(4): 825-837, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32167837

RESUMO

BACKGROUND: A major goal of rehabilitation after anterior cruciate ligament reconstruction (ACLR) is restoring quadriceps muscle strength. Unfortunately, current rehabilitation paradigms fall short of this goal, such that substantial quadriceps muscle strength deficits can limit return to play and increase the risk of recurrent injuries. Blood flow restriction training (BFRT) involves the obstruction of venous return to working muscles during exercise and may lead to better recovery of quadriceps muscle strength after ACLR. PURPOSE: To examine the efficacy of BFRT with high-intensity exercise on the recovery of quadriceps muscle function in patients undergoing ACLR. STUDY DESIGN: Randomized controlled trial; Level of evidence, 2. METHODS: A total of 34 patients (19 female, 15 male; mean age, 16.5 ± 2.7 years; mean height, 169.0 ± 19.7 cm; mean weight, 73.2 ± 17.7 kg) scheduled to undergo ACLR were randomly assigned to 1 of 4 groups: concentric (n = 8), eccentric (n = 8), concentric with BFRT (n = 9), and eccentric with BFRT (n = 9). The exercise component of the intervention consisted of patients performing a single-leg isokinetic leg press, at an intensity of 70% of the patients' 1-repetition maximum during either the concentric or eccentric action, for 4 sets of 10 repetitions 2 times per week for 8 weeks beginning at 10 weeks postoperatively. Patients randomized to the BFRT groups performed the leg-press exercise with a cuff applied to the thigh, set to a limb occlusion pressure of 80%. Isometric and isokinetic (60 deg/s) quadriceps peak torque, quadriceps muscle activation, and rectus femoris muscle volume were assessed before ACLR, after BFRT, and at the time that patients returned to activity and were converted to the change in values from baseline for analysis. Also, 1-way analyses of covariance were used to compare the change in values for each dependent variable between groups after BFRT and at return to activity (P ≤ .05). RESULTS: No significant differences were found between groups for any outcome measures at either time point (P > .05). CONCLUSION: An 8-week BFRT plus high-intensity exercise intervention did not significantly improve quadriceps muscle strength, activation, or volume. On the basis of our findings, the use of BFRT in conjunction with high-intensity resistance exercise in patients undergoing ACLR to improve quadriceps muscle function may not be warranted. REGISTRATION: NCT03141801 ( ClinicalTrials.gov identifier).


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior/reabilitação , Constrição , Músculo Quadríceps/irrigação sanguínea , Músculo Quadríceps/fisiologia , Adolescente , Lesões do Ligamento Cruzado Anterior/reabilitação , Lesões do Ligamento Cruzado Anterior/cirurgia , Terapia por Exercício , Feminino , Humanos , Masculino , Força Muscular , Torque , Adulto Jovem
13.
14.
Bone ; 130: 115118, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678490

RESUMO

Osteogenesis imperfecta (OI) is a rare and severe skeletal dysplasia marked by low bone mass and poor bone quality which is especially burdensome during childhood. Since clinical trials for pediatric OI are difficult, there is a widespread reliance on genetically modified murine models to understand the skeletal effects of emerging therapeutics. However a common model does not yet exist to understand how patient-specific genotype may influence treatment efficacy. Recently, sclerostin antibody (SclAb) has been introduced as a novel putative anabolic therapy for diseases of low bone mass, but effects in pediatric patients remain unexplored. In this study, we aim to establish a direct xenograft approach using OI patient-derived bone isolates which retain patient-specific genetic defects and cells residing in their intrinsic extracellular environment to evaluate the bone-forming effects of SclAb as a bridge to clinical trials. OI and age matched non-OI patient bone typically discarded as surgical waste during corrective orthopaedic procedures were collected, trimmed and implanted subcutaneously (s.c.) on the dorsal surface of 4-6-week athymic mice. A subset of implanted mice were evaluated at short (1 week), intermediate (4 week), and long-term (12 week) durations to assess bone cell survival and presence of donor bone cells in order to determine an appropriate treatment duration. Remaining implanted mice were randomly assigned to a two or four-week SclAb-treated (25mg/kg s.c. 2QW) or untreated control group. Immunohistochemistry determined osteocyte and osteoblast donor/host relationship, TRAP staining quantified osteoclast activity, and TUNEL assay was used to understand rates of bone cell apoptosis at each implantation timepoint. Longitudinal changes of in vivo µCT outcomes and dynamic histomorphometry were used to assess treatment response and ex vivo µCT and dynamic histomorphometry of host femora served as a positive internal control to confirm a bone forming response to SclAb. Human-derived osteocytes and lining cells were present up to 12 weeks post-implantation with nominal cell apoptosis in the implant. Sclerostin expression remained donor-derived throughout the study. Osterix expression was primarily donor-derived in treated implants and shifted in favor of the host when implants remained untreated. µCT measures of BMD, TMD, BV/TV and BV increased with treatment but response was variable and impacted by bone implant morphology (trabecular, cortical) which was corroborated by histomorphometry. There was no statistical difference between treated and untreated osteoclast number in the implants. Host femora confirmed a systemic bone forming effect of SclAb. Findings support use of the xenograft model using solid bone isolates to explore the effects of novel bone-targeted therapies. These findings will impact our understanding of SclAb therapy in pediatric OI tissue through establishing the efficacy of this treatment in human cells prior to extension to the clinic.

16.
17.
Sports Health ; 11(5): 440-445, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31265352

RESUMO

BACKGROUND: "Research-ready" evidence platforms that link sports data with anonymized electronic health records (EHRs) or other data are important tools for evaluating injury occurrence in response to changes in games, training, rules, and other factors. While there is agreement that high-quality data are essential, there is little evidence to guide data curation. HYPOTHESIS: We hypothesized that an EHR used in the course of clinical care and curated for research readiness can provide a robust evidence platform. Our purpose was to describe the data curation used for active injury surveillance by the National Football League (NFL). STUDY DESIGN: Dynamic cohort study. LEVEL OF EVIDENCE: Level 2. METHODS: Players provide informed consent for research activities through the collective bargaining process. A league-wide EHR is used to record injuries that come to the attention of the teams' athletic trainers and physicians, NFL medical spotters, or unaffiliated neurotrauma consultants. Information about football activities and injuries are linkable by player, setting, and event to other sports-related data, including game statistics and game-day stadium quality measures, using a unique player identification designed to protect player privacy. Ongoing data curation is used to review data completeness and accuracy and is adjusted over time in response to findings. RESULTS: The core data curation activities include monthly injury summaries to team staff, queries to resolve incomplete reporting, and periodic external checks. Experiences derived from producing more than 100 reports per year on diverse topics are used to update coding training and related guidance documents in response to missing data or inconsistent coding that is observed. Roughly 20% more injuries were recorded for the same "reportable" injuries after switching from targeted reporting to an EHR. CONCLUSION: Research-ready databases need systematic curation for quality and completeness, along with related action plans. More injuries were reported through EHR than through targeted reporting. CLINICAL RELEVANCE: Evidence-driven decision-making thrives on reliable data fine-tuned through systematic use, review, and ongoing adjustments to the curation process.


Assuntos
Traumatismos em Atletas/diagnóstico , Registros Eletrônicos de Saúde , Futebol Americano/lesões , Estudos de Coortes , Curadoria de Dados , Humanos , Armazenamento e Recuperação da Informação , Medicina Esportiva
18.
Am J Sports Med ; 47(9): 2067-2076, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31307223

RESUMO

BACKGROUND: Nearly three-quarters of anterior cruciate ligament (ACL) injuries occur as "noncontact" failures from routine athletic maneuvers. Recent in vitro studies revealed that repetitive strenuous submaximal knee loading known to especially strain the ACL can lead to its fatigue failure, often at the ACL femoral enthesis. HYPOTHESIS: ACL failure can be caused by accumulated tissue fatigue damage: specifically, chemical and structural evidence of this fatigue process will be found at the femoral enthesis of ACLs from tested cadaveric knees, as well as in ACL explants removed from patients undergoing ACL reconstruction. STUDY DESIGN: Controlled laboratory study. METHODS: One knee from each of 7 pairs of adult cadaveric knees were repetitively loaded under 4 times-body weight simulated pivot landings known to strain the ACL submaximally while the contralateral, unloaded knee was used as a comparison. The chemical and structural changes associated with this repetitive loading were characterized at the ACL femoral enthesis at multiple hierarchical collagen levels by employing atomic force microscopy (AFM), AFM-infrared spectroscopy, molecular targeting with a fluorescently labeled collagen hybridizing peptide, and second harmonic imaging microscopy. Explants from ACL femoral entheses from the injured knee of 5 patients with noncontact ACL failure were also characterized via similar methods. RESULTS: AFM-infrared spectroscopy and collagen hybridizing peptide binding indicate that the characteristic molecular damage was an unraveling of the collagen molecular triple helix. AFM detected disruption of collagen fibrils in the forms of reduced topographical surface thickness and the induction of ~30- to 100-nm voids in the collagen fibril matrix for mechanically tested samples. Second harmonic imaging microscopy detected the induction of ~10- to 100-µm regions where the noncentrosymmetric structure of collagen had been disrupted. These mechanically induced changes, ranging from molecular to microscale disruption of normal collagen structure, represent a previously unreported aspect of tissue fatigue damage in noncontact ACL failure. Confirmatory evidence came from the explants of 5 patients undergoing ACL reconstruction, which exhibited the same pattern of molecular, nanoscale, and microscale structural damage detected in the mechanically tested cadaveric samples. CONCLUSION: The authors found evidence of accumulated damage to collagen fibrils and fibers at the ACL femoral enthesis at the time of surgery for noncontact ACL failure. This tissue damage was similar to that found in donor knees subjected in vitro to repetitive 4 times-body weight impulsive 3-dimensional loading known to cause a fatigue failure of the ACL. CLINICAL RELEVANCE: These findings suggest that some ACL injuries may be due to an exacerbation of preexisting hierarchical tissue damage from activities known to place larger-than-normal loads on the ACL. Too rapid an increase in these activities could cause ACL tissue damage to accumulate across length scales, thereby affecting ACL structural integrity before it has time to repair. Prevention necessitates an understanding of how ACL loading magnitude and frequency are anabolic, neutral, or catabolic to the ligament.


Assuntos
Lesões do Ligamento Cruzado Anterior/fisiopatologia , Traumatismos em Atletas/fisiopatologia , Estresse Mecânico , Adolescente , Adulto , Lesões do Ligamento Cruzado Anterior/patologia , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior , Traumatismos em Atletas/patologia , Traumatismos em Atletas/cirurgia , Fenômenos Biomecânicos , Peso Corporal , Cadáver , Feminino , Humanos , Articulação do Joelho/fisiopatologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
J Orthop Res ; 37(9): 1910-1919, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31042312

RESUMO

Postnatal development and the physiological loading response of the anterior cruciate ligament (ACL) complex (ACL proper, entheses, and bony morphology) is not well understood. We tested whether the ACL-complex of two inbred mouse strains that collectively encompass the musculoskeletal variation observed in humans would demonstrate significant morphological differences following voluntary cage-wheel running during puberty compared with normal cage activity controls. Female A/J and C57BL/6J (B6) 6-week-old mice were provided unrestricted access to a standard cage-wheel for 4 weeks. A/J-exercise mice showed a 6.3% narrower ACL (p = 0.64), and a 20.1% more stenotic femoral notch (p < 0.01) while B6-exercise mice showed a 12.3% wider ACL (p = 0.10), compared with their respective controls. Additionally, A/J-exercise mice showed a 5.3% less steep posterior medial tibial slope (p = 0.07) and an 8.8% less steep posterior lateral tibial slope (p = 0.07), while B6-exercise mice showed a 9.8% more steep posterior medial tibial slope (p < 0.01) than their respective controls. A/J-exercise mice also showed more reinforcement of the ACL tibial enthesis with a 20.4% larger area (p < 0.01) of calcified fibrocartilage distributed at a 29.2% greater depth (p = 0.02) within the tibial enthesis, compared with their controls. These outcomes suggest exercise during puberty significantly influences ACL-complex morphology and that inherent morphological differences between these mice, as observed in their less active genetically similar control groups, resulted in a divergent phenotypic outcome between mouse strains. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1910-1919, 2019.


Assuntos
Ligamento Cruzado Anterior/patologia , Condicionamento Físico Animal , Puberdade/fisiologia , Animais , Lesões do Ligamento Cruzado Anterior/etiologia , Feminino , Fêmur/patologia , Articulação do Joelho/patologia , Camundongos , Camundongos Endogâmicos C57BL , Tíbia/patologia
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