ABSTRACT
BACKGROUND: Self-efficacy and fear of re-injury have been documented as factors related to an athlete's ability to return-to-sport after anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to compare psychological readiness between athletes injured in their primary mode of sport versus those injured outside of their primary sport following ACL reconstruction. HYPOTHESIS: Athletes sustaining 'in-sport' injuries will demonstrate poorer psychological readiness when compared their matched counterparts injured outside of their primary sport. STUDY DESIGN: Case-Control Study. METHODS: A single-surgeon database of 638 patients following ACL reconstruction was used to conduct a matched case-control analysis. Psychological readiness was examined 16-weeks postoperatively using the ACL-Return to Sport after Injury (ACL-RSI) questionnaire with subgroup analyses for the 'emotional', 'confidence' and 'injury-risk' subscales. Subject matching was performed for baseline patient and surgical demographics. All statistical comparisons were performed using a one-way (group) analysis variance (ANOVA) at a significance level of α = .05. RESULTS: Ninety-two matched patients (49 'in-sport' injuries, 43 'out-of-sport' injuries) were included in the final analysis. The 'in-sport' group exhibited significantly lower total ACL-RSI scores (55.3 ±12.9 versus 60.8 ±11.6, t = 2.747, P < .001) when compared to the 'out-of-sport' group. Subscale comparisons indicated lower 'emotional' (P < .016) and higher 'injury risk' (P < .001) psychological constructs for 'in-sport' athletes versus 'out-of-sport' athletes. No differences were found between groups for the 'confidence' subscale (P = .987). CONCLUSIONS: Athletes sustaining 'in-sport' ACL injuries demonstrated poorer psychological readiness when compared to athletes injured outside their primary sport when in preparation for return-to-sport activities following ACL reconstruction. CLINICAL RELEVANCE: Clinicians should consider the potential impact of mode of injury on psychological readiness when returning athletes to sport after ACL reconstruction.
ABSTRACT
The formation and stability of drops in the presence of nanoparticles was studied in a microfluidic device to directly observe the early stages of Pickering emulsification (low interfacial coverage). We observed several key differences between oil droplet necking and rupture in aqueous phases of nanoparticles (methylated silica) and well-characterised surfactant systems. The presence of particles did not influence drop formation dynamics and thus the size of the drops generated. In addition, observations of in-channel drop stability shortly after formation (several milliseconds) indicated that particles in the aqueous phase slow film thinning processes, but do not prevent coalescence. In contrast, downstream collection and densification (at the microchannel outlet), showed that particle-stabilised drops do not coalesce for several weeks, above a critical particle concentration. The implications of our results for droplet microfluidics and our understanding of conventional emulsification systems are discussed.
