Evaluate active knee joint position sense (JPS) throughout rehabilitation after anterior cruciate ligament reconstruction (ACLR).
Longitudinal.
Motion laboratory.
Twenty-two individuals post-ACLR and 22 activity-matched non-injured controls performed weight-bearing and non-weight-bearing knee JPS tests. The ACLR participants performed at three functional timepoints: T1, able to perform single-leg sit-to-stand; T2, able to hop maximally; T3, cleared for return to sports. Controls performed on one occasion.
Constant, absolute, variable errors (CE, AE, VE) and interlimb symmetry estimates (100% signifying perfect symmetry), for 40° and 65° knee flexion target angles.
For the weight-bearing 40° condition, CE and AE of the ACLR knee significantly increased from T1 to T2 (P = 0.010) and T1 to T3 (P = 0.002). Consequently, interlimb asymmetry for AE significantly increased from T1 (AEsym% = 101.2% ± 55.4%) to T3 (AEsym% = 139.7% ± 54.8%). Compared to controls, AE for the ACLR knee was significantly smaller at T1 (P = 0.016). No other significant differences were observed.
Smaller JPS errors at early rehabilitation while weight-bearing may have been due to heightened quadriceps activation and increased γ motor neuron sensitivity, compensating for deficient ACL mechanoreceptors. In contrast, non-weight-bearing testing did not reveal changes over time. Clinicians are advised to consider these distinctions when assessing proprioception at different rehabilitation stages.
To explore head impact magnitude (linear head acceleration and rotational velocity) during heading for four different header types in youth male footballers. A secondary objective was to explore whether head impact magnitude was influenced by player-related factors (i.e. age, neck strength).
An observational field-based research design was utilised for this research.
27 youth male footballers (mean age14.81, SD1.88) from one football club.
Peak linear acceleration and peak angular velocity were measured during four different header types (two from 15-m and two from 5-m). Maximal isometric neck strength of each player was also assessed (flexors, extensors, left and right-side flexors).
Statistically significant differences were observed between header type and both peak linear acceleration (F(3,78) = 60.90, R2 = 0.76, p=<0.001) and peak angular velocity (F(3,78) = 43.63, R2 = 0.75, p=<0.001). In terms of players related factors, for linear acceleration, 6% (P = 0.008) of the variance was predicted by age, and for angular velocity, 12% (P = 0.003) was predicted by age, with neck strength accounting for <9% of the variance.
In this youth cohort, head impact magnitude during heading is influenced by the type of header being performed.
This study aimed to: (i) understand how women perceived their recently developed patellofemoral pain (PFP) regarding its cause, prognosis, and willingness to seek treatment; (ii) investigate self-reported function, knee-related quality of life (QoL), fear of movement, and physical activity level at the onset of PFP.
Mixed-methods longitudinal study.
University.
Sixty-eight pain-free women were followed up over one year.
Those who developed PFP were interviewed within one month of the development of symptoms. Self-reported function, kinesiophobia, knee-related QoL, and physical activity were obtained at baseline and follow-up assessments.
Twenty-one women developed PFP. Most participants reported believing the increase in physical activity and/or sitting time was associated with the onset of PFP. Many reported believing symptoms would improve over time without any treatment. Only a small number of participants intended to seek care. Quantitatively, decreases in self-reported function and QoL, as well as increases in the physical activity level were observed after PFP development.
Although decreases in self-reported function and QoL were observed, women reported believing their PFP is self-limiting and do not need treatment. Strategies to accurately disseminate knowledge about PFP are needed to help stimulating early care.
The purpose of this study was to explore self-perceived changes in athlete journey trajectory, or shifts, after ACLR that facilitate or hinder physical activity participation among youth.
Ten participants were included in this study at a median of 5.9 years after adolescent ACLR. Using an interpretive phenomenological methodology, semi-structured interviews with each participant were recorded and transcribed verbatim. Data collection focused on participants’ lived experiences of reintegration to physical activity after ACLR. Thematic analyses were guided by the procedures of the constant comparative method.
Nineteen distinct shifts were identified from participants’ perspectives, categorized into the main classification scheme of 1) environmental shifts (extrinsic demands, built environment, social network), 2) psychological shifts (expectations, motivation, meaning of sports, accountability, priorities, athlete identity, mental health, confidence, knowledge, character, participation mentality), and 3) physical shifts (movement competence, sport participation, physical activity, normalization, knee health). Factors perceived to induce shifts were categorized as natural, injury-driven, or life transition-driven.
In the years following adolescent ACLR, young athletes experience physical, psychological, and environment shifts that impact physical activity participation. These findings provide important insight for future work that aims to optimize physical activity outcomes after an injury-related disruption in the athlete journey.
To report isometric hip adduction squeeze and abduction press strength values of elite-level youth male and female soccer players and examine if differences exist between sexes, and age-groups.
Cross-sectional cohort study.
Elite youth soccer academy.
102 soccer players (n = 64; male, n = 38 female) competing in the national youth soccer leagues from under (U) 14–19 years of age level (U-14, U-15, U-17, U-19).
Isometric hip adduction and abduction strength values were measured with a ForceFrame in various testing positions.
Isometric hip adduction and abduction strength values are presented. Male U-17 and U-19 players demonstrated significantly greater (p < 0.05) absolute(N) and relative (N/kg) hip adduction and abduction strength than their female counterparts, with large (η2 = 0.068–0.227) and medium-to-large (η2 = 0.049–0.234) effect size, respectively. Significant differences in absolute strength, but not relative strength, were observed for hip adduction and abduction between male age-groups (U-14, U-15, U-17, U-19), with hip abduction strength differences only existing between U-14 and U-17 groups. No significant differences in hip strength were observed between U-17 and U-19 groups for female players.
Male youth soccer players have higher absolute and relative hip adduction and abduction strength than females at the U-17 and U-19 level.