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1.
Arthritis Rheumatol ; 76(4): 566-576, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37961759

ABSTRACT

OBJECTIVE: The objective of this study was to compare the vertical (vGRF), anterior-posterior (apGRF), and medial-lateral (mlGRF) ground reaction force (GRF) profiles throughout the stance phase of gait (1) between individuals 6 to 12 months post-anterior cruciate ligament reconstruction (ACLR) and uninjured matched controls and (2) between ACLR and individuals with differing radiographic severities of knee osteoarthritis (KOA), defined as Kellgren and Lawrence (KL) grades KL2, KL3, and KL4. METHODS: A total of 196 participants were included in this retrospective cross-sectional analysis. Gait biomechanics were collected from individuals 6 to 12 months post-ACLR (n = 36), uninjured controls matched to the ACLR group (n = 36), and individuals with KL2 (n = 31), KL3 (n = 67), and KL4 osteoarthritis (OA) (n = 26). Between-group differences in vGRF, apGRF, and mlGRF were assessed in reference to the ACLR group throughout each percentage of stance phase using a functional linear model. RESULTS: The ACLR group demonstrated lower vGRF and apGRF in early and late stance compared to the uninjured controls, with large effects (Cohen's d range: 1.35-1.66). Conversely, the ACLR group exhibited greater vGRF (87%-90%; 4.88% body weight [BW]; d = 0.75) and apGRF (84%-94%; 2.41% BW; d = 0.79) than the KL2 group in a small portion of late stance. No differences in mlGRF profiles were observed between the ACLR and either the uninjured controls or the KL2 group. The magnitude of difference in GRF profiles between the ACLR and OA groups increased with OA disease severity. CONCLUSION: Individuals 6 to 12 months post-ACLR exhibit strikingly similar GRF profiles as individuals with KL2 KOA, suggesting both patient groups may benefit from targeted interventions to address aberrant GRF profiles.


Subject(s)
Anterior Cruciate Ligament Injuries , Osteoarthritis, Knee , Humans , Retrospective Studies , Cross-Sectional Studies , Gait , Biomechanical Phenomena , Knee Joint
2.
Arthritis Care Res (Hoboken) ; 74(7): 1172-1178, 2022 07.
Article in English | MEDLINE | ID: mdl-33460530

ABSTRACT

OBJECTIVE: To compare T1ρ relaxation times of the medial and lateral regions of the patella and femoral trochlea at 6 and 12 months following anterior cruciate ligament reconstruction (ACLR) on the ACLR and contralateral extremity. Greater T1ρ relaxation times are associated with a lower proteoglycan density of articular cartilage. METHODS: This study involved 20 individuals (11 males, 9 females; mean ± SD age 22 ± 3.9 years, weight 76.11 ± 13.48 kg, and height 178.32 ± 12.32 cm) who underwent a previous unilateral ACLR using a patellar tendon autograft. Magnetic resonance images from both extremities were acquired at 6 and 12 months post-ACLR. Voxel by voxel T1ρ relaxation times were calculated using a 5-image sequence. The medial and lateral regions of the femoral trochlea and patellar articular cartilage were manually segmented on both extremities. Separate extremity (ACLR and contralateral extremity) by time (6 months and 12 months) analysis of variance tests were performed for each region (P < 0.05). RESULTS: For the medial patella and lateral trochlea, T1ρ relaxation times increased in both extremities between 6 and 12 months post-ACLR (medial patella P = 0.012; lateral trochlea P = 0.043). For the lateral patella, T1ρ relaxation times were significantly greater on the contralateral extremity compared to the ACLR extremity (P = 0.001). The T1ρ relaxation times of the medial trochlea on the ACLR extremity were significantly greater at 6 (P = 0.005) and 12 months (P < 0.001) compared to the contralateral extremity. T1ρ relaxation times of the medial trochlea significantly increased from 6 to 12 months on the ACLR extremity (P = 0.003). CONCLUSION: Changes in T1ρ relaxation times occur within the first 12 months following ACLR in specific regions of the patellofemoral joint on the ACLR and contralateral extremity.


Subject(s)
Anterior Cruciate Ligament Injuries , Anterior Cruciate Ligament Reconstruction , Cartilage, Articular , Patellofemoral Joint , Adolescent , Adult , Anterior Cruciate Ligament Injuries/surgery , Anterior Cruciate Ligament Reconstruction/methods , Cartilage, Articular/diagnostic imaging , Cartilage, Articular/surgery , Female , Humans , Knee Joint/surgery , Magnetic Resonance Imaging/methods , Male , Patellofemoral Joint/diagnostic imaging , Patellofemoral Joint/surgery , Young Adult
3.
Orthop J Sports Med ; 9(7): 23259671211016424, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34368382

ABSTRACT

BACKGROUND: Excessively high joint loading during dynamic movements may negatively influence articular cartilage health and contribute to the development of posttraumatic osteoarthritis after anterior cruciate ligament reconstruction (ACLR). Little is known regarding the link between aberrant jump-landing biomechanics and articular cartilage health after ACLR. PURPOSE/HYPOTHESIS: The purpose of this study was to determine the associations between jump-landing biomechanics and tibiofemoral articular cartilage composition measured using T1ρ magnetic resonance imaging (MRI) relaxation times 12 months postoperatively. We hypothesized that individuals who demonstrate alterations in jump-landing biomechanics, commonly observed after ACLR, would have longer T1ρ MRI relaxation times (longer T1ρ relaxation times associated with less proteoglycan density). STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 27 individuals with unilateral ACLR participated in this cross-sectional study. Jump-landing biomechanics (peak vertical ground-reaction force [vGRF], peak internal knee extension moment [KEM], peak internal knee adduction moment [KAM]) and T1ρ MRI were collected 12 months postoperatively. Mean T1ρ relaxation times for the entire weightbearing medial femoral condyle, lateral femoral condyle (global LFC), medial tibial condyle, and lateral tibial condyle (global LTC) were calculated bilaterally. Global regions of interest were further subsectioned into posterior, central, and anterior regions of interest. All T1ρ relaxation times in the ACLR limb were normalized to the uninjured contralateral limb. Linear regressions were used to determine associations between T1ρ relaxation times and biomechanics after accounting for meniscal/chondral injury. RESULTS: Lower ACLR limb KEM was associated with longer T1ρ relaxation times for the global LTC (ΔR 2 = 0.24; P = .02), posterior LTC (ΔR 2 = 0.21; P = .03), and anterior LTC (ΔR 2 = 0.18; P = .04). Greater ACLR limb peak vGRF was associated with longer T1ρ relaxation times for the global LFC (ΔR 2 = 0.20; P = .02) and central LFC (ΔR 2 = 0.15; P = .05). Peak KAM was not associated with T1ρ outcomes. CONCLUSION: At 12 months postoperatively, lower peak KEM and greater peak vGRF during jump landing were related to longer T1ρ relaxation times, suggesting worse articular cartilage composition.

4.
J Athl Train ; 56(11): 1173-1179, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-33787883

ABSTRACT

CONTEXT: Hypertrophy of the infrapatellar fat pad (IFP) in idiopathic knee osteoarthritis has been linked to deleterious synovial changes and joint pain related to mechanical tissue impingement. Yet little is known regarding the IFP's volumetric changes after anterior cruciate ligament reconstruction (ACLR). OBJECTIVES: To examine changes in IFP volume between 6 and 12 months after ACLR and determine associations between patient-reported outcomes and IFP volume at each time point as well as the volume change over time. In a subset of individuals, we examined interlimb IFP volume differences 12 months post-ACLR. STUDY DESIGN: Prospective cohort study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: We studied 26 participants (13 women, 13 men, age = 21.88 ± 3.58 years, body mass index = 23.82 ± 2.21 kg/m2) for our primary aims and 13 of those participants (8 women, 5 men, age = 21.15 ± 3.85 years, body mass index = 23.01 ± 2.01 kg/m2) for our exploratory aim. MAIN OUTCOME MEASURE(S): Using magnetic resonance imaging, we evaluated the IFP volume change between 6 and 12 months post-ACLR in the ACLR limb and between-limbs differences at 12 months in a subset of participants. International Knee Documentation Committee subjective knee evaluation (IKDC) scores were collected at 6-month and 12-month follow-ups, and associations between IFP volume and patient-reported outcomes were determined. RESULTS: The IFP volume in the ACLR limb increased from 6 months (19.67 ± 6.30 cm3) to 12 months (21.26 ± 6.91 cm3) post-ACLR. Greater increases of IFP volume between 6 and 12 months were significantly associated with better 6-month IKDC scores (r = .44, P = .03). The IFP volume was greater in the uninjured limb (22.71 ± 7.87 cm3) than in the ACLR limb (20.75 ± 9.03 cm3) 12 months post-ACLR. CONCLUSIONS: The IFP volume increased between 6 and 12 months post-ACLR; however, the IFP volume of the ACLR limb remained smaller than that of the uninjured limb at 12 months. In addition, those with better knee function 6 months post-ACLR demonstrated greater increases in IFP volume between 6 and 12 months post-ACLR. This suggests that greater IFP volumes may play a role in long-term joint health after ACLR.


Subject(s)
Anterior Cruciate Ligament Injuries , Anterior Cruciate Ligament Reconstruction , Male , Female , Humans , Adolescent , Young Adult , Adult , Anterior Cruciate Ligament Injuries/surgery , Prospective Studies , Anterior Cruciate Ligament Reconstruction/methods , Knee Joint/surgery , Adipose Tissue/surgery , Patient Reported Outcome Measures
5.
Med Sci Sports Exerc ; 52(10): 2086-2095, 2020 10.
Article in English | MEDLINE | ID: mdl-32251254

ABSTRACT

Transcutaneous electrical nerve stimulation (TENS) facilitates quadriceps voluntary activation in experimental settings. Augmenting therapeutic exercise (TE) with TENS may enhance the benefits of TE in individuals with knee osteoarthritis (KOA) and quadriceps voluntary activation failure (QVAF). PURPOSE: This study aimed to determine the effect of TENS + TE on patient-reported function, quadriceps strength, and voluntary activation, as well as physical performance compared with sham TENS + TE (Sham) and TE alone in individuals with symptomatic KOA and QVAF. METHODS: Ninety individuals participated in a double-blinded randomized controlled trial. Everyone received 10 standardized TE sessions of physical therapy. TENS + TE and Sham groups applied the respective devices during all TE sessions and throughout activities of daily living over 4 wk. The Western Ontario and McMaster University Osteoarthritis Index (WOMAC), quadriceps strength, and voluntary activation, as well as a 20-m walk test, chair-stand test, and stair-climb test were performed at baseline, after the 4-wk intervention (post 1) and at 8 wk after the start of the intervention (post 2). Mixed-effects models were used to determine between-group differences between baseline and post 1, as well as baseline and post 2. RESULTS: Improvements in WOMAC subscales, quadriceps strength, and voluntary activation, 20-m walk times, chair-stand repetitions, and stair-climb time were found at post 1 and post 2 compared with baseline for all groups (P < 0.05). WOMAC Pain and Stiffness improved in the TENS + TE group compared with TE alone at post 1 (P < 0.05); yet, no other between-group differences were found. CONCLUSIONS: TE effectively improved patient-reported function, quadriceps strength, and voluntary activation, as well as physical performance in individuals with symptomatic KOA and QVAF, but augmenting TE with TENS did not improve the benefits of TE.


Subject(s)
Exercise Therapy , Osteoarthritis, Knee/rehabilitation , Quadriceps Muscle/physiology , Transcutaneous Electric Nerve Stimulation , Activities of Daily Living , Adult , Aged , Double-Blind Method , Exercise Test/methods , Female , Humans , Male , Middle Aged , Muscle Strength , Osteoarthritis, Knee/physiopathology , Patient Reported Outcome Measures , Physical Functional Performance , Walking Speed
6.
Med Sci Sports Exerc ; 52(4): 785-794, 2020 04.
Article in English | MEDLINE | ID: mdl-31809411

ABSTRACT

PURPOSE: To compare gait biomechanics throughout stance phase 6 and 12 months after unilateral anterior cruciate ligament reconstruction (ACLR) between ACLR and contralateral limbs and compared with controls. METHODS: Vertical ground reaction force (vGRF), knee flexion angle (KFA), and internal knee extension moment (KEM) were collected bilaterally 6 and 12 months post-ACLR in 30 individuals (50% female, 22 ± 3 yr, body mass index = 23.8 ± 2.2 kg·m) and at a single time point in 30 matched uninjured controls (50% female, 22 ± 4 yr, body mass index = 23.6 ± 2.1 kg·m). Functional analyses of variance were used to evaluate the effects of limb (ACLR, contralateral, and control) and time (6 and 12 months) on biomechanical outcomes throughout stance. RESULTS: Compared with the uninjured controls, the ACLR group demonstrated bilaterally lesser vGRF (ACLR, 9% body weight [BW]; contralateral, 4%BW) during early stance and greater vGRF during midstance (ACLR, 5%BW; contralateral, 4%BW) 6 months post-ACLR. Compared to the uninjured controls, the ACLR group demonstrated bilaterally lesser vGRF (ACLR, 10%BW; contralateral, 8%BW) during early stance and greater vGRF during midstance (ACLR, 5%BW; contralateral, 5%BW) 12 months post-ACLR. Compared with controls, the ACLR limb demonstrated lesser KFA during early stance at 6 (2.3°) and 12 months post-ACLR (2.0°), and the contralateral limb demonstrated lesser KFA during early stance at 12 months post-ACLR (2.8°). Compared with controls, the ACLR limb demonstrated lesser KEM during early stance at both 6 months (0.011BW × height) and 12 months (0.007BW × height) post-ACLR, and the contralateral limb demonstrated lesser KEM during early stance only at 12 months (0.006BW × height). CONCLUSIONS: Walking biomechanics are altered bilaterally after ACLR. During the first 12 months post-ACLR, both the ACLR and contralateral limbs demonstrate biomechanical differences compared with control limbs. Differences between the contralateral and control limbs increase from 6 to 12 months post-ACLR.


Subject(s)
Anterior Cruciate Ligament Injuries/physiopathology , Anterior Cruciate Ligament Injuries/surgery , Anterior Cruciate Ligament Reconstruction , Gait , Leg/physiopathology , Biomechanical Phenomena , Female , Follow-Up Studies , Humans , Knee Joint/physiopathology , Longitudinal Studies , Male , Prospective Studies , Young Adult
7.
J Ultrasound Med ; 39(5): 957-965, 2020 May.
Article in English | MEDLINE | ID: mdl-31763713

ABSTRACT

OBJECTIVES: To evaluate changes in the femoral cartilage cross-sectional area (CSA) measured with ultrasound (US) between baseline and 1000, 2000, 3000, 4000, and 5000 steps of walking on a treadmill. METHODS: Forty-one healthy individuals completed a single testing session. Participants rested with their knees extended on a plinth for 45 minutes to unload the femoral cartilage. Ultrasound was used to acquire images of the femoral cartilage before the treadmill-walking protocol. After the baseline US acquisition, participants walked on a treadmill at their preferred overground walking speed for 1000 steps, after which additional US images of the femoral cartilage were acquired. This process was repeated after 2000, 3000, 4000, and 5000 steps. A 1-way repeated-measures analysis of variance compared the CSA across the 6 step counts. An analysis of variance with repeated measures on time and Bonferroni corrected planned comparisons (.05/5) were used to evaluate differences in the femoral cartilage at each step count compared to baseline. RESULTS: The study included 20 male and 21 female participants (mean age ± SD, 21.5 ± 2.8 years; mean body mass index, 24.3 ± 3.4 kg/m 2 ). The CSAs were significantly greater at the 2000-step (1.27 ± 1.75 mm 2 ; P < .001), 4000-step (0.89 ± 1.17 mm2; P < .001), and 5000-step (2.10 ± 1.73 mm 2 ; P < .001) points compared to baseline. The CSA was significantly less at the 3000-step point (1.05 ± 1.29 mm 2 ; P < .001) compared to baseline. CONCLUSIONS: Changes in the CSA after walking may be dependent on the number of steps. The participants had a significant decrease in the CSA after 3000 steps of normal walking and a significant increase in the CSA after 2000, 4000, and 5000 steps of normal walking.


Subject(s)
Cartilage, Articular/anatomy & histology , Exercise Test/methods , Knee Joint/anatomy & histology , Ultrasonography/methods , Walking/statistics & numerical data , Adolescent , Adult , Female , Femur/anatomy & histology , Humans , Male , Walking/physiology , Young Adult
8.
Knee ; 26(5): 1067-1072, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31340891

ABSTRACT

BACKGROUND: Knee varus alignment may increase loading in the medial tibiofemoral compartment, which can increase strain on the articular cartilage. Knee valgus unloader braces seek to reduce loading through the medial femoral compartment, but their effects on cartilage characteristics during dynamic tasks have not been evaluated. OBJECTIVE: To determine the effects of a knee valgus unloader brace on medial femoral articular cartilage deformation following a single 5000-step walking protocol in individuals with varus-knee alignment. METHODS: Twenty-four healthy individuals (63% female, BMI = 22 ±â€¯3 kg/m2, age = 21 ±â€¯3 years) completed two testing sessions (braced and unbraced) separated by one week. During both sessions, femoral cartilage ultrasound images were acquired prior to and following a 5000-step treadmill walking protocol at self-selected speed. Percent change scores in medial cartilage cross-sectional area (MCCA) were calculated and used as the primary outcome, and compared between the braced and unbraced conditions. RESULTS: There was no difference in percent change of MCCA between conditions (braced = -2.77%, unbraced = -3.15%, p = 0.699). Individuals whose cartilage deformed more than a previously established minimal detectable change (MDC ≥ 1.58 mm2) deformed less during the braced condition (braced = -2.94%, unbraced = -6.34%, p = 0.028), compared to individuals who did not deform greater than the MDC (n = 15, braced = -2.67%, unbraced = -1.23%, p = 0.210). CONCLUSIONS: There was no significant difference in MCCA percent change between the braced and unbraced conditions across the entire cohort; yet a valgus unloader braces may serve as a potential intervention strategy for reducing articular cartilage deformation in certain varus-aligned individuals who normally undergo measurable deformation during walking.


Subject(s)
Braces/adverse effects , Cartilage, Articular/physiopathology , Gait/physiology , Genu Valgum/therapy , Knee Joint/diagnostic imaging , Walking/physiology , Adolescent , Adult , Biomechanical Phenomena , Cartilage, Articular/diagnostic imaging , Cross-Over Studies , Female , Genu Valgum/diagnosis , Genu Valgum/physiopathology , Healthy Volunteers , Humans , Knee Joint/physiopathology , Male , Range of Motion, Articular/physiology , Ultrasonography , Weight-Bearing/physiology , Young Adult
9.
Med Sci Sports Exerc ; 51(2): 246-254, 2019 02.
Article in English | MEDLINE | ID: mdl-30157111

ABSTRACT

PURPOSE: The association between lower-extremity loading and clinically relevant knee symptoms at different time points after anterior cruciate ligament reconstruction (ACLR) is unclear. Vertical ground reaction force (vGRF) from walking was compared between individuals with and without clinically relevant knee symptoms in three cohorts: <12 months post-ACLR, 12-24 months post-ACLR, and >24 months post-ACLR. METHODS: One hundred twenty-eight individuals with unilateral ACLR were classified as symptomatic or asymptomatic, based on previously defined cutoff values for the Knee Osteoarthritis and Injury Outcome Score (<12 months post-ACLR [symptomatic n = 28, asymptomatic n = 24]; 12-24 months post-ACLR [symptomatic n = 15, asymptomatic n = 15], and >24 months post-ACLR [symptomatic, n = 13; asymptomatic, n = 33]). Vertical ground reaction force exerted on the ACLR limb was collected during walking gait, and functional analyses of variance were used to evaluate the effects of symptoms and time post-ACLR on vGRF throughout stance phase (α = 0.05). RESULTS: Symptomatic individuals, <12 months post-ACLR, demonstrated less vGRF during both vGRF peaks (i.e., weight acceptance and propulsion) and greater vGRF during midstance, compared to asymptomatic individuals. Vertical ground reaction force characteristics were not different between symptomatic and asymptomatic individuals for most of stance in individuals between 12 and 24 months post-ACLR. Symptomatic individuals who were >24 months post-ACLR, exhibited greater vGRF during both peaks, but lesser vGRF during midstance, compared to asymptomatic individuals. CONCLUSION: Relative to asymptomatic individuals, symptomatic individuals are more likely to underload the ACLR limb early after ACLR (i.e., <12 months) during both vGRF peaks, but overload the ACLR limb, during both vGRF peaks, at later time points (i.e., >24 months). We propose these differences in lower-extremity loading during walking might have implications for long-term knee health, and should be considered when designing therapeutic interventions for individuals with an ACLR.


Subject(s)
Anterior Cruciate Ligament Injuries/physiopathology , Anterior Cruciate Ligament Injuries/surgery , Anterior Cruciate Ligament Reconstruction , Walking/physiology , Adolescent , Adult , Anterior Cruciate Ligament Injuries/metabolism , Biomechanical Phenomena , Cartilage, Articular/metabolism , Cross-Sectional Studies , Female , Humans , Lower Extremity/physiology , Male , Osteoarthritis, Knee/etiology , Patient Reported Outcome Measures , Risk Factors , Time Factors , Young Adult
10.
Med Sci Sports Exerc ; 51(4): 630-639, 2019 04.
Article in English | MEDLINE | ID: mdl-30444797

ABSTRACT

PURPOSE: Aberrant walking biomechanics after anterior cruciate ligament reconstruction (ACLR) are hypothesized to be associated with deleterious changes in knee cartilage. T1ρ magnetic resonance imaging (MRI) is sensitive to decreased proteoglycan density of cartilage. Our purpose was to determine associations between T1ρ MRI interlimb ratios (ILR) and walking biomechanics 6 months after ACLR. METHODS: Walking biomechanics (peak vertical ground reaction force (vGRF), vGRF loading rate, knee extension moment, knee abduction moment) were extracted from the first 50% of stance phase in 29 individuals with unilateral ACLR. T1ρ MRI ILR (ACLR limb/uninjured limb) was calculated for regions of interest in both medial and lateral femoral (LFC) and medial and lateral tibial condyles. Separate, stepwise linear regressions were used to determine associations between biomechanical outcomes and T1ρ MRI ILR after accounting for walking speed and meniscal/chondral injury (P ≤ 0.05). RESULTS: Lesser peak vGRF in the ACLR limb was associated with greater T1ρ MRI ILR for the LFC (posterior ΔR = 0.14, P = 0.05; central ΔR = 0.15, P = 0.05) and medial femoral condyle (central ΔR = 0.24, P = 0.01). Lesser peak vGRF loading rate in the ACLR limb (ΔR = 0.21, P = 0.02) and the uninjured limb (ΔR = 0.27, P = 0.01) was associated with greater T1ρ MRI ILR for the anterior LFC. Lesser knee abduction moment for the injured limb was associated with greater T1ρ MRI ILR for the anterior LFC (ΔR = 0.16, P = 0.04) as well as the posterior medial tibial condyle (ΔR = 0.13, P = 0.04). CONCLUSION: Associations between outcomes related to lesser mechanical loading during walking and greater T1ρ MRI ILR were found 6 months after ACLR. Although preliminary, our results suggest that underloading of the ACLR limb at 6 months after ACLR may be associated with lesser proteoglycan density in the ACLR limb compared with the uninjured limb.


Subject(s)
Anterior Cruciate Ligament Injuries/physiopathology , Anterior Cruciate Ligament Injuries/surgery , Anterior Cruciate Ligament Reconstruction , Cartilage, Articular/diagnostic imaging , Gait/physiology , Knee Joint/diagnostic imaging , Anterior Cruciate Ligament Injuries/diagnostic imaging , Anterior Cruciate Ligament Reconstruction/methods , Arthroscopy , Biomechanical Phenomena , Cartilage, Articular/chemistry , Cartilage, Articular/physiopathology , Cross-Sectional Studies , Female , Humans , Knee Joint/chemistry , Knee Joint/physiopathology , Magnetic Resonance Imaging/methods , Male , Osteoarthritis, Knee/etiology , Proteoglycans/analysis , Risk Factors , Young Adult
11.
Knee Surg Sports Traumatol Arthrosc ; 27(8): 2632-2642, 2019 Aug.
Article in English | MEDLINE | ID: mdl-30560446

ABSTRACT

PURPOSE: Quadriceps weakness following anterior cruciate ligament reconstruction (ACLR) is linked to decreased patient-reported function, altered lower extremity biomechanics and tibiofemoral joint space narrowing. It remains unknown if quadriceps weakness is associated with early deleterious changes to femoral cartilage composition that are suggestive of posttraumatic osteoarthritis development. The purpose of the cross-sectional study was to determine if quadriceps strength was associated with T1ρ relaxation times, a marker of proteoglycan density, of the articular cartilage in the medial and lateral femoral condyles 6 months following ACLR. It is hypothesized that individuals with weaker quadriceps would demonstrate lesser proteoglycan density. METHODS: Twenty-seven individuals (15 females, 12 males) with a patellar tendon autograft ACLR underwent isometric quadriceps strength assessments in 90°of knee flexion during a 6-month follow-up exam. Magnetic resonance images (MRI) were collected bilaterally and voxel by voxel T1ρ relaxation times were calculated using a five-image sequence and a monoexponential equation. Following image registration, the articular cartilage for the weight-bearing surfaces of the medial and lateral femoral condyles (MFC and LFC) were manually segmented and further sub-sectioned into posterior, central and anterior regions of interest (ROI) based on the corresponding meniscal anatomy viewed in the sagittal plane. Univariate linear regression models were used to determine the association between quadriceps strength and T1ρ relaxation times in the entire weight-bearing MFC and LFC, as well as the ROI in each respective limb. RESULTS: Lesser quadriceps strength was significantly associated with greater T1ρ relaxation times in the entire weight-bearing MFC (R2 = 0.14, P = 0.05) and the anterior-MFC ROI (R2 = 0.22, P = 0.02) of the ACLR limb. A post hoc analysis found lesser strength and greater T1ρ relaxation times were significantly associated in a subsection of participants (n = 18) without a concomitant medial tibiofemoral compartment meniscal or chondral injury in the entire weight-bearing MFC, as well as anterior-MFC and central-MFC ROI of the ACLR and uninjured limb. CONCLUSIONS: The association between weaker quadriceps and greater T1ρ relaxation times in the MFC suggests deficits in lower extremity muscle strength may be related to cartilage composition as early as 6 months following ACLR. Maximizing quadriceps strength in the first 6 months following ACLR may be critical for promoting cartilage health early following ACLR. LEVEL OF EVIDENCE: Prognostic level 1.


Subject(s)
Anterior Cruciate Ligament Reconstruction , Cartilage, Articular/diagnostic imaging , Muscle Strength , Proteoglycans/analysis , Quadriceps Muscle/physiology , Adolescent , Adult , Anterior Cruciate Ligament Injuries/surgery , Cartilage, Articular/chemistry , Cross-Sectional Studies , Female , Femur/surgery , Humans , Isometric Contraction , Knee Joint/diagnostic imaging , Knee Joint/surgery , Magnetic Resonance Imaging/methods , Male , Meniscus , Patellar Ligament/transplantation , Transplantation, Autologous , Young Adult
12.
Estud. Psicol. (Campinas, Online) ; 35(3): 259-263, jul.-set. 2018.
Article in English | LILACS | ID: biblio-953532

ABSTRACT

This article describes the work that the author has been focusing on over the last 15 years: understanding the social and emotional world of the gifted child and adolescent. The article describes the history behind how the author came to develop his thinking on the now popular concept, "strengths of the heart". Strengths of the heart include a triad of psychological concepts: social skills, emotional intelligence, and character strengths and virtues. Together, this triad of psychological concepts, strengths of the heart, predict to important life outcomes, including success, psychological health, happiness, and subjective well-being.


Este artigo descreve o trabalho em que o autor tem se focado nos últimos 15 anos: compreender o mundo social e emocional da criança e do adolescente superdotados. O artigo descreve a história por trás de como o autor veio a desenvolver seu pensamento sobre o conceito atualmente disseminado de "forças do coração". O conceito de forças do coração inclui uma tríade de conceitos psicológicos: habilidades sociais, inteligência emocional e forças e virtudes do caráter. Conjuntamente, essa tríade de conceitos psicológicos, as forças do coração, antevê importantes resultados na vida do indivíduo, incluindo sucesso, saúde psicológica, felicidade e bem-estar subjetivo.


Subject(s)
Humans , Child, Gifted , Emotional Intelligence
13.
J Orthop Res ; 36(11): 2932-2940, 2018 11.
Article in English | MEDLINE | ID: mdl-29781550

ABSTRACT

The study sought to determine the association between gait biomechanics (vertical ground reaction force [vGRF], vGRF loading rate [vGRF-LR]) collected 6 months following anterior cruciate ligament reconstruction (ACLR) with patient-reported outcomes at 12 months following ACLR. Walking gait biomechanics and all subsections of the Knee Injury and Osteoarthritis Outcomes Score (KOOS) were collected at 6 and 12 months following ACLR, respectively, in 25 individuals with a unilateral ACLR. Peak vGRF and peak instantaneous vGRF-LR were extracted from the first 50% of the stance phase. Limb symmetry indices (LSI) were used to normalize outcomes in the ACLR limb to that of the uninjured limb (ACLR/uninjured). Linear regression analyses were used to determine associations between biomechanical outcomes and KOOS while accounting for walking speed. Receiver operator characteristic curves were used to determine the accuracy of 6-month biomechanical outcomes for identifying individuals with acceptable patient-reported outcomes, using previously defined KOOS cut-off scores, 12 months post-ACLR. Individuals with lower peak vGRF LSI 6 months post-ACLR demonstrated worse patient-reported outcomes (KOOS Pain, Activities of Daily life, Sport and Recreation, Quality of Life) at the 12-month exam. A peak vGRF LSI ≥0.99 6 months following ACLR associated with 13.33× higher odds of reporting acceptable patient-reported outcomes 12 months post-ACLR. Lesser peak vGRF LSI during walking at 6-months post-ACLR may be a critical indicator of worse future patient-reported outcomes. Clinical significance achieving early symmetrical lower extremity loading and minimizing under-loading of the ACLR limb during walking may be a potential therapeutic target for improving patient-reported outcomes post-ACLR. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2932-2940, 2018.


Subject(s)
Anterior Cruciate Ligament Reconstruction/rehabilitation , Gait , Patient Reported Outcome Measures , Adolescent , Adult , Female , Humans , Longitudinal Studies , Male , Prospective Studies , Young Adult
14.
Clin Biomech (Bristol, Avon) ; 53: 79-85, 2018 03.
Article in English | MEDLINE | ID: mdl-29471191

ABSTRACT

BACKGROUND: Aberrant walking-gait and jump-landing biomechanics may influence the development of post-traumatic osteoarthritis and increase the risk of a second anterior cruciate ligament injury, respectively. It remains unknown if individuals who demonstrate altered walking-gait biomechanics demonstrate similar altered biomechanics during jump-landing. Our aim was to determine associations in peak knee biomechanics and limb-symmetry indices between walking-gait and jump-landing tasks in individuals with a unilateral anterior cruciate ligament reconstruction. METHODS: Thirty-five individuals (74% women, 22.1 [3.4] years old, 25 [3.89] kg/m2) with an anterior cruciate ligament reconstruction performed 5-trials of self-selected walking-gait and jump-landing. Peak kinetics and kinematics were extracted from the first 50% of stance phase during walking-gait and first 100 ms following ground contact for jump-landing. Pearson product-moment (r) and Spearman's Rho (ρ) analyses were used to evaluate relationships between outcome measures. Significance was set a priori (P ≤ 0.05). FINDINGS: All associations between walking-gait and jump-landing for the involved limb, along with the majority of associations for limb-symmetry indices and the uninvolved limb, were negligible and non-statistically significant. There were weak significant associations for instantaneous loading rate (ρ = 0.39, P = 0.02) and peak knee abduction angle (ρ = 0.36, p = 0.03) uninvolved limb, as well as peak abduction displacement limb-symmetry indices (ρ= - 0.39, p = 0.02) between walking-gait and jump-landing. INTERPRETATION: No systematic associations were found between walking-gait and jump-landing biomechanics for either limb or limb-symmetry indices in people with unilateral anterior cruciate ligament reconstruction. Individuals with an anterior cruciate ligament reconstruction who demonstrate high-involved limb loading or asymmetries during jump-landing may not demonstrate similar biomechanics during walking-gait.


Subject(s)
Anterior Cruciate Ligament Injuries/surgery , Anterior Cruciate Ligament Reconstruction , Gait/physiology , Knee Joint/physiopathology , Osteoarthritis, Knee/surgery , Adult , Anterior Cruciate Ligament Injuries/physiopathology , Biomechanical Phenomena , Biophysics , Female , Humans , Kinetics , Knee/surgery , Male , Movement/physiology , Osteoarthritis, Knee/physiopathology , Walking , Young Adult
15.
Arthritis Care Res (Hoboken) ; 70(8): 1132-1140, 2018 08.
Article in English | MEDLINE | ID: mdl-29193888

ABSTRACT

OBJECTIVE: To determine whether walking speed, collected at 6 and 12 months following anterior cruciate ligament reconstruction (ACLR), is associated with inter-extremity differences in proteoglycan density, measured via T1ρ magnetic resonance imaging, in tibiofemoral articular cartilage 12 months following ACLR. METHODS: Twenty-one individuals with a unilateral patellar-tendon autograft ACLR (10 women and 11 men, mean ± SD age 23.9 ± 2.7 years, mean ± SD body mass index 23.9 ± 2.7 kg/m2 ) were recruited for participation in this study. Walking speed was collected using 3-dimensional motion capture at 6 and 12 months following ACLR. The articular cartilage of the medial femoral condyle (MFC) and lateral femoral condyle and medial and lateral tibial condyles was manually segmented and subsectioned into 3 regions of interest (anterior, central, and posterior) based on the location of the meniscus in the sagittal plane. Inter-extremity mean T1ρ relaxation time ratios (T1ρ ACLR extremity / T1ρ contralateral extremity) were calculated and used for analysis. Pearson product-moment correlations were used to determine associations between walking speed and inter-extremity differences in T1ρ relaxation time ratios. RESULTS: Slower walking speed 6 months post-ACLR was significantly associated with higher T1ρ relaxation time ratios in the MFC of the ACLR extremity 12 months following ACLR (posterior MFC, r = -0.51, P = 0.02; central MFC, r = -0.47, P = 0.04). Similarly, slower walking speed at 12 months post-ACLR was significantly associated with higher T1ρ relaxation time ratios in the posterior MFC ACLR extremity (r = -0.47, P = 0.04) 12 months following ACLR. CONCLUSION: Slower walking speed at 6 and 12 months following ACLR may be associated with early proteoglycan density changes in medial femoral compartment cartilage health in the first 12 months following ACLR.


Subject(s)
Anterior Cruciate Ligament Injuries/diagnostic imaging , Anterior Cruciate Ligament Injuries/surgery , Anterior Cruciate Ligament Reconstruction/methods , Cartilage, Articular/diagnostic imaging , Imaging, Three-Dimensional , Walking Speed/physiology , Adult , Age Factors , Anterior Cruciate Ligament Reconstruction/rehabilitation , Arthroscopy , Cartilage, Articular/pathology , Female , Follow-Up Studies , Humans , Injury Severity Score , Magnetic Resonance Imaging/methods , Male , Recovery of Function , Sex Factors , Time Factors , Treatment Outcome , Young Adult
16.
Estud. psicol. (Campinas) ; 32(4): 717-727, Oct.-Dec. 2015.
Article in English | LILACS | ID: lil-764133

ABSTRACT

The twice exceptional are students who have both high ability and a disability or disorder. The ability can be in any culturally-valued domain, including high intelligence, academics, the visual or performing arts, and athletics. The co-existing disability can be physical, medical, or psychological. There is a growing literature of scholarly opinion about twice exceptionality; however, there are few well-designed empirical investigations of gifted students with anxiety, depression, bipolar disorder, attention-deficit/hyperactivity disorder, eating disorders, conduct problems, or medical, physical or sensory disabilities. This article examines a few key issues about the twice exceptional student and then discusses what we know about the gifted students with attention-deficit hyperactivity disorder and gifted students with learning disabilities. The article also provides a brief discussion on suicide and the gifted student.


Estudantes com dupla excepcionalidade são aqueles que apresentam, concomitantemente, alta capacidade e uma deficiência ou doença. A capacidade pode ser expressa em qualquer domínio culturalmente valorizado, incluindo alta inteligência, rendimento acadêmico, artes visuais ou performativas e esporte. Por outro lado, a deficiência coexistente pode ser física, médica ou psicológica. Há uma literatura acadêmica crescente sobre a dupla excepcionalidade, sendo importante destacar, no entanto, um número reduzido de pesquisas empíricas desenvolvidas junto a alunos superdotados que apresentam ansiedade, depressão, transtorno bipolar, transtorno de deficit de atenção/hiperatividade, transtornos alimentares, problemas de conduta ou incapacidades físicas ou sensoriais. Este artigo examina algumas questões-chave sobre o discente duplamente excepcional e, em seguida, discute o que se sabe sobre os alunos superdotados com transtorno de deficit de atenção/hiperatividade e aqueles com dificuldades de aprendizagem. O artigo também fornece uma breve discussão sobre o suicídio e o aluno superdotado.


Subject(s)
Humans , Attention Deficit Disorder with Hyperactivity , Autistic Disorder , Child, Exceptional , Child, Gifted
17.
Estud. psicol. (Campinas) ; 32(4): 717-727, out.-dez. 2015.
Article in English | Index Psychology - journals | ID: psi-64733

ABSTRACT

The twice exceptional are students who have both high ability and a disability or disorder. The ability can be in any culturally-valued domain, including high intelligence, academics, the visual or performing arts, and athletics. The co-existing disability can be physical, medical, or psychological. There is a growing literature of scholarly opinion about twice exceptionality; however, there are few well-designed empirical investigations of gifted students with anxiety, depression, bipolar disorder, attention-deficit/hyperactivity disorder, eating disorders, conduct problems, or medical, physical or sensory disabilities. This article examines a few key issues about the twice exceptional student and then discusses what we know about the gifted students with attention-deficit hyperactivity disorder and gifted students with learning disabilities. The article also provides a brief discussion on suicide and the gifted student.(AU)


Estudantes com dupla excepcionalidade são aqueles que apresentam, concomitantemente, alta capacidade e uma deficiência ou doença. A capacidade pode ser expressa em qualquer domínio culturalmente valorizado, incluindo alta inteligência, rendimento acadêmico, artes visuais ou performativas e esporte. Por outro lado, a deficiência coexistente pode ser física, médica ou psicológica. Há uma literatura acadêmica crescente sobre a dupla excepcionalidade, sendo importante destacar, no entanto, um número reduzido de pesquisas empíricas desenvolvidas junto a alunos superdotados que apresentam ansiedade, depressão, transtorno bipolar, transtorno de deficit de atenção/hiperatividade, transtornos alimentares, problemas de conduta ou incapacidades físicas ou sensoriais. Este artigo examina algumas questões-chave sobre o discente duplamente excepcional e, em seguida, discute o que se sabe sobre os alunos superdotados com transtorno de deficit de atenção/hiperatividade e aqueles com dificuldades de aprendizagem. O artigo também fornece uma breve discussão sobre o suicídio e o aluno superdotado.(AU)


Subject(s)
Humans , Attention Deficit Disorder with Hyperactivity , Autistic Disorder , Child, Exceptional , Child, Gifted
18.
Estud. psicol. (Campinas) ; 30(2): 219-229, Apr.-June 2013. ilus
Article in English | LILACS | ID: lil-684542

ABSTRACT

There is a considerable amount of literature on leadership, particularly as it relates to organizations, government, and the military. However, educators and psychologists know considerably less about early precursors of leadership, how leadership develops in youth, possible gender differences, and the relationship of leadership, intelligence and creativity. A global consensus exists that leaders are needed and that we shouldn't delay the early development of leadership skills. The authors propose a model to enhance creative leadership and introduce a teacher-completed rating scale, the Gifted Rating Scales to help accomplish this. As demonstrated, there are possibilities to detect early creative and intellectual giftedness among children and youngsters in the classrooms and expectations to move from a basic level of competence to reach an elite or expert level in any field, facilitating the emergence of leadership...


O tema da liderança vem sendo debatido intensamente na literatura, principalmente no ambiente empresarial, governamental e militar. Entretanto, o conhecimento é bastante escasso entre os educadores e psicólogos sobre os indicadores da liderança, ou melhor, como a liderança se desenvolve entre os jovens, possíveis diferenças de sexo, e a relação da inteligência com a criatividade. Os autores apresentam um modelo para estimular a liderança criativa assim como uma escala para professores avaliarem superdotação a fim de atingir este objetivo. Como demonstrado, existem possibilidades de detectar a superdotação intelectual e criativa entre crianças e jovens e expectativas de superação de um nível básico de competência para atingir o de especialista ou esperto, em qualquer área, permitindo assim o aparecimento da liderança...


Subject(s)
Humans , Aptitude , Creativity , Leadership
19.
Estud. psicol. (Campinas) ; 30(2): 219-229, Apr.-June 2013. ilus
Article in English | Index Psychology - journals | ID: psi-61836

ABSTRACT

There is a considerable amount of literature on leadership, particularly as it relates to organizations, government, and the military. However, educators and psychologists know considerably less about early precursors of leadership, how leadership develops in youth, possible gender differences, and the relationship of leadership, intelligence and creativity. A global consensus exists that leaders are needed and that we shouldn't delay the early development of leadership skills. The authors propose a model to enhance creative leadership and introduce a teacher-completed rating scale, the Gifted Rating Scales to help accomplish this. As demonstrated, there are possibilities to detect early creative and intellectual giftedness among children and youngsters in the classrooms and expectations to move from a basic level of competence to reach an elite or expert level in any field, facilitating the emergence of leadership.(AU)


O tema da liderança vem sendo debatido intensamente na literatura, principalmente no ambiente empresarial, governamental e militar. Entretanto, o conhecimento é bastante escasso entre os educadores e psicólogos sobre os indicadores da liderança, ou melhor, como a liderança se desenvolve entre os jovens, possíveis diferenças de sexo, e a relação da inteligência com a criatividade. Os autores apresentam um modelo para estimular a liderança criativa assim como uma escala para professores avaliarem superdotação a fim de atingir este objetivo. Como demonstrado, existem possibilidades de detectar a superdotação intelectual e criativa entre crianças e jovens e expectativas de superação de um nível básico de competência para atingir o de especialista ou esperto, em qualquer área, permitindo assim o aparecimento da liderança.(AU)


Subject(s)
Humans , Creativity , Aptitude , Leadership
20.
J Interv Cardiol ; 26(1): 29-37, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23419105

ABSTRACT

BACKGROUND: EuroSCORE and completeness of revascularization predicts long-term survival after multivessel PCI (MV-PCI). The SYNTAX-Score has also been proposed to predict clinical outcome. The prognostic impact of these scores to predict long-term survival after PCI has not yet been compared. METHODS AND RESULTS: Long-term survival was assessed in 740 patients undergoing MV-PCI. We calculated EuroSCORE, SYNTAX-Score, STS-Score, the clinical SYNTAX-Score (CSS), and the "post-PCI residual SYNTAX-Score." Mean follow-up time was 4.5 ± 2.5 years. 341 patients (46%) were treated for ACS (STEMI N = 191; NSTEMI N = 150). 113 patients (15%) underwent PCI of left main coronary artery. The EuroSCORE was significantly lower for stable patients compared to patients with ACS (stable 4.1 ± 4.5, NSTEMI 13.9 ± 13.3, STEMI 18.1 ± 18.7, p < 0.001). The differences in the SYNTAX-Score were less obvious but even significant (stable 14.9 ± 8.6, NSTEMI 17.8 ± 9.9, STEMI 18.3 ± 9.0; p < 0.001). Patients in the highest tertiles of each risk score experienced a dramatically elevated mortality rate compared to the extremely low mortality rate in the lower tertiles (p log-rank <0.001). This comparison remained significant for the EuroSCORE and STS-Score but not for the SYNTAX-Score, when analysis was restricted to stable patients. The multivariate Cox-regression-analysis confirmed the logistic EuroSCORE, EuroSCORE II, and the STS-Score as independent predictors of long-term mortality, whereas the SYNTAX-Score (including residual form) and the CSS had no predictive value. CONCLUSION: The EuroSCORE and the STS-Score outperforms the SYNTAX-Score and the CSS in predicting long-term survival following MV-PCI. In addition, the residual SYNTAX-Score predicts long-term survival not independently.


Subject(s)
Acute Coronary Syndrome/mortality , Acute Coronary Syndrome/therapy , Coronary Artery Disease/mortality , Coronary Artery Disease/therapy , Risk Assessment , Aged , Angioplasty, Balloon, Coronary , Female , Follow-Up Studies , Humans , Male , Predictive Value of Tests , Prognosis , Stents
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