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Context
Decreased postural stability is a primary risk factor for lower limb musculoskeletal injuries. During athletic competitions, cryotherapy may be applied during short breaks in play or during half-time; however, its effects on postural stability remain unclear.Objective
To investigate the acute effects of a 15-minute ankle-joint cryotherapy application on dynamic postural stability.Design
Controlled laboratory study.Setting
University biomechanics laboratory.Patients or Other Participants
A total of 29 elite-level collegiate male field-sport athletes (age = 20.8 ± 1.12 years, height = 1.80 ± 0.06 m, mass = 81.89 ± 8.59 kg) participated.Intervention(s)
Participants were tested on the anterior (ANT), posterolateral (PL), and posteromedial (PM) reach directions of the Star Excursion Balance Test before and after a 15-minute ankle-joint cryotherapy application.Main Outcome Measure(s)
Normalized reach distances; sagittal-plane kinematics of the hip, knee, and ankle joints; and associated mean velocity of the center-of-pressure path during performance of the ANT, PL, and PM reach directions of the Star Excursion Balance Test.Results
We observed a decrease in reach-distance scores for the ANT, PL, and PM reach directions from precryotherapy to postcryotherapy (P < .05). No differences were observed in hip-, knee-, or ankle-joint sagittal-plane kinematics (P > .05). We noted a decrease in mean velocity of the center-of-pressure path from precryotherapy to postcryotherapy (P < .05) in all reach directions.Conclusions
Dynamic postural stability was adversely affected immediately after cryotherapy to the ankle joint.Key Words: postural balance, lower limb, kineticsKey Points
- A 15-minute cryotherapy application to the ankle joint decreased cutaneous temperature recorded over the anterior talofibular ligament and deltoid ligament.
- Reach distances in the anterior, posterolateral, and posteromedial directions of the Star Excursion Balance Test and center-of-pressure mean velocity decreased after cryotherapy.
- A 15-minute cryotherapy application negatively influenced dynamic postural-stability performance.
- Elite-level field-based athletes should undergo a rewarming period before returning to participation after cryotherapy to the ankle joint to ensure they are not predisposed to injury due to decreased dynamic postural stability.
Objective:
To present 3 cases of plantar-plate rupture and turf-toe injury in contact athletes at 1 university and to discuss appropriate diagnosis and treatment algorithms for each case.Background:
Turf toe is a common injury in athletes participating in outdoor cutting sports. However, it has been used as an umbrella term to describe many different injuries of the great toe. In some cases, the injury can be so severe that the plantar plate and sesamoid apparatus may be ruptured. These patients may be better managed with surgery than with traditional nonoperative interventions.Differential Diagnosis:
Turf toe, plantar-plate disruption, sesamoid fracture.Treatment:
For stable injuries in which the plantar plate is not completely disrupted, nonoperative treatment with casting or a stiff-soled shoe, gradual weight bearing, and rehabilitation is the best practice. Unstable injuries require surgical intervention and plantar-plate repair.Uniqueness:
Turf toe and injury to the first metatarsophalangeal joint are relatively common injuries in athletes, but few researchers have detailed the operative and nonoperative treatments of plantar-plate disruption in these patients. We examine 3 cases that occurred over 4 seasons on a collegiate football team.Conclusions:
Turf toe represents a wide array of pathologic conditions involving the first metatarsophalangeal joint. Stress and instability testing are key components to assess in determining whether surgical intervention is warranted to restore optimal function. Stiffer-soled shoes or shoes with steel-plate insertions may help to prevent these injuries and are useful tools for protection during the rehabilitation period.Key Words: metatarsophalangeal joint, great toe, football playersTurf toe is a common injury in athletes participating in outdoor cutting sports. Clanton and Ford1 reported that injury to the foot was the third leading cause of missed athletic participation. Damage to the metatarsophalangeal joint (MTPJ) represents a large percentage of those injuries. However, since Bowers and Martin2 coined the term turf toe, it has been a poorly studied topic of substantial controversy. They originally described turf toe as a sprain to the first MTPJ, but in many instances, the injury has been attributed incorrectly to various pathologic conditions involving the first ray.2 Turf toe historically has been managed nonoperatively with a stiff-soled shoe or short walking boot. Yet in severe cases, the plantar plate may be ruptured and disrupted. These injuries are easy to overlook on physical examination. Therefore, the purpose of our study was to review 3 cases of injury to the plantar plate of the first MTPJ in contact athletes and to focus on diagnosis and treatment of the more severe toe injuries. 相似文献Method: Integrating established methodologies based on human-centred design and universal design, a framework was formulated to coordinate the robot design process over successive iterations of prototype development.
Results: An account is given of how the framework was practically applied to the problem of developing a personal service robot. Application of the framework led to the formation of several design goals which addressed a wide range of identified user needs. The resultant prototype solution, which consisted of several component elements, succeeded in demonstrating the performance stipulated by all of the proposed metrics.
Conclusions: Application of the framework resulted in the development of a complex prototype that addressed many aspects of the functional and usability requirements of a personal service robot. Following the process led to several important insights which directly benefit the development of subsequent prototypes.
- Implications for Rehabilitation
This research shows how universal design might be used to formulate usability requirements for assistive service robots.
A framework is presented that guides the process of designing service robots in a human-centred way.
Through practical application of the framework, a prototype robot system that addressed a range of identified user needs was developed.
Method: Publications were identified from 1991 to 2015 in ERIC, web of science via web of knowledge, CINAHL, SCOPUS, IEEEXplore, engineering village, business source complete and PubMed databases using search terms and synonyms for accommodations, advanced manufacturing, additive manufacturing, assistive technology (AT), barriers, engineering, facilitators, instructor, laboratory, STEM education, science, students with disabilities and technology.
Results: Twenty-two of the 233 publications that met the review’s inclusion criteria were examined. Barriers and facilitators were grouped based on the international classification of functioning, disability and health framework (ICF). None of the studies directly found barriers or facilitators to SwD-P in science or engineering laboratories within postsecondary environments. The literature is not clear on the issues specifically related to SwD-P.
Conclusion: Given these findings, further research (e.g., surveys or interviews) should be conducted to identify more details to obtain more substantial information on the barriers that may prevent SwD-P from fully participating in S&E instructional laboratories.
- Implications for Rehabilitation
Students with disabilities remain underrepresented going into STEM careers.
A need exist to help uncover barriers students with disabilities encounter in STEM laboratory.
Environments.
Accommodations and strategies that facilitate participation in STEM laboratory environments are promising for students with disabilities
Background
Numerous methods have been proposed that use submaximal loads to predict one repetition maximum (1RM). One common method applies standard linear regression equations to load and average vertical lifting velocity (Vmean) data developed during squat jumps or three bench press throw (BP-T). The main aim of this project was to determine which combination of three submaximal loads during BP-T result in the most accurate prediction of 1RM Smith Machine bench press strength in healthy individuals.Methods
In this study combinations of three BP-T loads were used to predict 1RM Smith Machine bench press strength. Additionally, we examined whether regression models developed using peak vertical bar velocity (Vpeak), rather than Vmean, provide the most accurate prediction of Smith Machine bench press 1RM. 1RM Smith Machine bench press strength was measured directly in 12 healthy regular weight trainers (body mass?=?80.8?±?5.7 kg). Two to three days later a linear position transducer attached to the collars on a Smith Machine was used to record Vmean and Vpeak during BP-T between 30 and 70% of 1RM (10% increments).Results
Repeated measures analysis of variance testing showed that the mean values for slope and ordinate intercept for the regression models at each of the load ranges differed significantly depending on whether Vmean or Vpeak were used in the prediction models (P?<?0.001). Conversely, the abscissa intercept did not differ significantly between either measure of vertical bar velocity at each load range. The key finding in this study was that 1RM Smith Machine bench press strength can be determined with high relative accuracy by examining Vmean and Vpeak during BP-T over three loads, with the most precise models using Vpeak during loads representing 30, 40 and 50% of 1RM (R 2 ?=?0.96, SSE?=?4.2 kg).Conclusions
These preliminary findings indicate that exercise programmers working with normal healthy populations can accurately predict Smith Machine 1RM bench press strength using relatively light load Smith Machine BP-T testing, avoiding the need to expose their clients to potentially injurious loads.Method: Eight young adults, eight TD 5–8 year-old children, and seven 5–8 year-old children with CIs participated. Labial /ba/–/wa/ and alveolar /da/–/ja/ continua stimuli were presented, with each continuum consisting of nine synthetic stimuli varying in F2 and F3 transition duration. Participants were asked to label the stimuli as either a stop or glide, and responses were analysed for phonetic boundaries and slopes.
Result: For the /ba/–/wa/ contrast, children with CIs required longer transition durations compared to TD children or adults to cross from one phoneme category to another. The children with CIs demonstrated less confidence in labelling the stimuli (i.e. less steep slopes) than the TD children or the adults. For the /da/–/ja/ contrast, the children with CIs showed less steep slope values than adults.
Conclusion: These results suggest that there are differences in the way TD children and children with CIs develop and maintain phonetic categories, perhaps differences in phonetic representation or in linking acoustic and phonetic representations. 相似文献