Analysis of Kinematic and Muscular Fatigue in Long-Distance Swimmers.

Muscle fatigue is a complex phenomenon that is influenced by the type of activity performed and often manifests as a decline in motor performance (mechanical failure). The purpose of our study was to investigate the compensatory strategies used to mitigate mechanical failure. A cohort of 21 swimmers underwent a front-crawl swimming task, which required the consistent maintenance of a constant speed for the maximum duration. The evaluation included three phases: non-fatigue, pre-mechanical failure, and mechanical failure. We quantified key kinematic metrics, including velocity, distance travelled, stroke frequency, stroke length, and stroke index. In addition, electromyographic (EMG) metrics, including the Root-Mean-Square amplitude and Mean Frequency of the EMG power spectrum, were obtained for 12 muscles to examine the electrical manifestations of muscle fatigue. Between the first and second phases, the athletes covered a distance of 919.38 ± 147.29 m at an average speed of 1.57 ± 0.08 m/s with an average muscle fatigue level of 12%. Almost all evaluated muscles showed a significant increase (p < 0.001) in their EMG activity, except for the latissimus dorsi, which showed a 17% reduction (ES 0.906, p < 0.001) during the push phase of the stroke cycle. Kinematic parameters showed a 6% decrease in stroke length (ES 0.948, p < 0.001), which was counteracted by a 7% increase in stroke frequency (ES -0.931, p < 0.001). Notably, the stroke index also decreased by 6% (ES 0.965, p < 0.001). In the third phase, characterised by the loss of the ability to maintain the predetermined rhythm, both EMG and kinematic parameters showed reductions compared to the previous two phases. Swimmers employed common compensatory strategies for coping with fatigue; however, the ability to maintain a predetermined motor output proved to be limited at certain levels of fatigue and loss of swimming efficiency (Protocol ID: NCT06069440).

Severe Open Dislocation of the Hip with Exposed Femoral Head: A Case Report.

CASE: A 54-year-old woman was brought to our emergency department with an inferomedial open hip dislocation without fracture secondary to a railway trauma. We performed hip reduction, wound debridement, and stabilization with external fixation. After 7 months, hip arthroplasty was performed for severe hip instability and avascular necrosis of the femoral head. CONCLUSION: Open hip dislocation is an uncommon injury that is caused by high-energy trauma. It may be associated with serious management problems and complications, including infection and avascular necrosis of the femoral head.

Conservative management of isolated medial subtalar joint dislocations in volleyball players: a report of three cases and literature review.

Isolated subtalar dislocations (SDs) are rare injuries, representing only 1% of all foot traumas. In the current literature, only a few reports have described this acute injury as a consequence of low-middle-energy trauma during sports activities and none in professional or recreational volleyball players. Further, to the best of our knowledge, no validated standard rehabilitation programs have been described for SDs as most of them are usually treated like an ankle sprain. This report describes 3 cases of isolated, closed medial SD, which occurred during non-professional volleyball activities. All cases were successfully treated by the same conservative method: standard radiographs for diagnosis, closed reduction, subsequent CT scan to exclude associated lesions, 4-week immobilization in a below-knee cast and an early physiokinesis therapy program. Further, a review of the recent literature concerning SD was performed. The standard method applied allowed our patients to return to full sports activity at 3 months from trauma, reaching a medium AOFAS score of 96.6 at minimum follow-up of 48 months. The treated cases and the review of the literature suggest that a conservative method and early mobilization should be the first-choice treatment for closed SD, even in volleyball players. Despite the absence of a sport-specific rehabilitation program for these injuries, early physiokinesis therapy, after no more than 4-week immobilization period, allowed the improvement of our patients' hindfoot stability and their fast return to full sports activities, without any recurrence at minimum follow-up of 2 years.