Effects of the Flying Start on Estimated Short Sprint Profiles Using Timing Gates.

Short sprints are predominantly assessed using timing gates and analyzed through parameters of the mono-exponential equation, including estimated maximal sprinting speed (MSS) and relative acceleration (TAU), derived maximum acceleration (MAC), and relative propulsive maximal power (PMAX), further referred to as the No Correction model. However, the frequently recommended flying start technique introduces a bias during parameter estimation. To correct this, two additional models (Estimated TC and Estimated FD) were proposed. To estimate model precision and sensitivity to detect the change, 31 basketball players executed multiple 30 m sprints. Athlete performance was simultaneously measured by a laser gun and timing gates positioned at 5, 10, 20, and 30 m. Short sprint parameters were estimated using a laser gun, representing the criterion measure, and five different timing gate models, representing the practical measures. Only the MSS parameter demonstrated a high agreement between the laser gun and timing gate models, using the percent mean absolute difference (%MAD) estimator (%MAD < 10%). The MSS parameter also showed the highest sensitivity, using the minimum detectable change estimator (%MDC95), with an estimated %MDC95 < 17%. Interestingly, sensitivity was the highest for the No Correction model (%MDC95 < 7%). All other parameters and models demonstrated an unsatisfying level of sensitivity. Thus, sports practitioners should be cautious when using timing gates to estimate maximum acceleration indices and changes in their respective levels.

Necrotizing Fasciitis-Severe Complication of Bullous Pemphigoid: A Systematic Review, Risk Factors, and Treatment Challenges.

Background and objectives: Bullous pemphigoid (BP), the most common subepidermal autoimmune skin blistering disease (AIBD) has an estimated annual incidence of 2.4 to 42.8 new cases per million in different populations, designating it an orphan disease. Characterized by disruption of the skin barrier combined with therapy-induced immunosuppression, BP could pose a risk for skin and soft tissue infections (SSTI). Necrotizing fasciitis (NF) is a rare necrotizing skin and soft tissue infection, with a prevalence of 0.40 cases per 100,000 to 15.5 cases per 100,000 population, often associated with immunosuppression. Low incidences of NF and BP classify them both as rare diseases, possibly contributing to the false inability of making a significant correlation between the two. Here, we present a systematic review of the existing literature related to the ways these two diseases correlate. Materials and methods: This systematic review was conducted according to the PRISMA guidelines. The literature review was conducted using PubMed (MEDLINE), Google Scholar, and SCOPUS databases. The primary outcome was prevalence of NF in BP patients, while the secondary outcome was prevalence and mortality of SSTI in BP patients. Due to the scarcity of data, case reports were also included. Results: A total of 13 studies were included, six case reports of BP complicated by NF with six retrospective studies and one randomized multicenter trial of SSTIs in BP patients. Conclusions: Loss of skin integrity, immunosuppressive therapy, and comorbidities commonly related to BP patients are risk factors for necrotizing fasciitis. Evidence of their significant correlation is emerging, and further studies are deemed necessary for the development of BP-specific diagnostic and treatment protocols.

Within-Unit Reliability and Between-Units Agreement of the Commercially Available Linear Position Transducer and Barbell-Mounted Inertial Sensor to Measure Movement Velocity.

Jovanovic, M and Jukic, I. Within-unit reliability and between-units agreement of the commercially available linear position transducer and barbell-mounted inertial sensor to measure movement velocity. J Strength Cond Res XX(X): 000-000, 2020-The purpose of this study was to investigate the within-unit reliability of GymAware linear position transducer (GYM) and PUSH2 inertial sensor to measure mean velocity (MV) and peak velocity (PV) during hexagonal barbell deadlift (HBD) and to examine the agreement between GYM and PUSH2 devices. Twelve strength-trained men performed 2 HBD one-repetition maximum (1RM) sessions followed by 2 repetitions to failure assessments with 80 and 90% of daily 1RM. Barbell MV and PV were simultaneously monitored with 2 GYM and PUSH2 devices during all assessments. An ordinary least products regression was used to assess within-units agreement and whether PUSH2 can accurately predict GYM velocity. In addition, residual standard error (RSE) and smallest detectable change in load (SDC%1RM) were also calculated. GYM devices have been shown to be highly reproducible devices (RSE = 0.019-0.021 m·s; SDC%1RM = 1.795-2.679%). However, PUSH2 devices displayed a substantial amount of error (RSE = 0.133-0.220 m·s) and lack of sensitivity (SCD%1RM = 14.113-14.558%) to detect smallest change in load, which makes them untrustworthy for a regular use for monitoring athletes. Although very high correlations (r = 0.915-0.948) have been observed between PUSH2 and GYM velocity recordings, PUSH2 overestimated both MV and PV as indicated by high fixed and proportional bias. The findings of the present study suggest that sport professionals should not use PUSH2 devices when the aim is to accurately monitor velocity variables during HBD exercise because low within-unit agreement and high fixed and proportional bias and RSE compared with GYM devices may compromise the utility of the collected data.

Bias in estimated short sprint profiles using timing gates due to the flying start: simulation study and proposed solutions.

Short sprints are most frequently evaluated and modeled using timing gates. Flying start distance is often recommended to avoid premature timing system triggering by lifting knees or swinging arms. This results in timing system initiation not being aligned with the initial force application, which yields bias in estimated short sprint parameters. This simulation study aims to explore the effects of the flying start distance on bias and sensitivity to detect changes in short sprint parameters using three models: the contemporary No Correction model and two proposed Estimated time correction (Estimated TC), and Estimated flying distance (Estimated FD) models. In conclusion, both the Estimated TC and Estimated FD models provided more precise parameter estimates, but surprisingly, the No correction model provided higher sensitivity for specific parameter changes. Besides standardizing the sprint starting technique for the short sprint performance monitoring, practitioners are recommended to utilize and track the results of all three models.

Sprint Mechanical Characteristics of Female Soccer Players: A Retrospective Pilot Study to Examine a Novel Approach for Correction of Timing Gate Starts.

The purpose of this study was to compare model estimates of linear sprint mechanical characteristics using timing gates with and without time correction. High-level female soccer players (n = 116) were evaluated on a 35-m linear sprint with splits at 5, 10, 20, 30, and 35 m. A mono-exponential function was used to model sprint mechanical metrics in three ways: without a time correction, with a fixed (+0.3 s) time correction, and with an estimated time correction. Separate repeated-measures ANOVAs compared the sprint parameter estimates between models and also the residuals between models. Differences were identified between all modeled sprint mechanical metrics; however, comparable estimates to the literature occurred when either time correction was used. Bias for both time-corrected models was reduced across all sprint distances compared to the uncorrected model. This study confirms that a time correction is warranted when using timing gates at the start line to model sprint mechanical metrics. However, determining whether fixed or estimated time corrections provide greater accuracy requires further investigation.

Monitoring the Heart Rate Variability Responses to Training Loads in Competitive Swimmers Using a Smartphone Application and the Banister Impulse-Response Model.

PURPOSE: First, to examine whether heart rate variability (HRV) responses can be modeled effectively via the Banister impulse-response model when the session rating of perceived exertion (sRPE) alone, and in combination with subjective well-being measures, are utilized. Second, to describe seasonal HRV responses and their associations with changes in critical speed (CS) in competitive swimmers. METHODS: A total of 10 highly trained swimmers collected daily 1-minute HRV recordings, sRPE training load, and subjective well-being scores via a novel smartphone application for 15 weeks. The impulse-response model was used to describe chronic root mean square of the successive differences (rMSSD) responses to training, with sRPE and subjective well-being measures used as systems inputs. Changes in CS were obtained from a 3-minute all-out test completed in weeks 1 and 14. RESULTS: The level of agreement between predicted and actual HRV data was R2 = .66 (.25) when sRPE alone was used. Model fits improved in the range of 4% to 21% when different subjective well-being measures were combined with sRPE, representing trivial-to-moderate improvements. There were no significant differences in weekly group averages of log-transformed (Ln) rMSSD (P = .34) or HRV coefficient of variation of Ln rMSSD (P = .12); however, small-to-large changes (d = 0.21-1.46) were observed in these parameters throughout the season. Large correlations were observed between seasonal changes in HRV measures and CS (changes in averages of Ln rMSSD: r = .51, P = .13; changes in coefficient of variation of Ln rMSSD: r = -.68, P = .03). CONCLUSION: The impulse-response model and data collected via a novel smartphone application can be used to model HRV responses to swimming training and nontraining-related stressors. Large relationships between seasonal changes in measured HRV parameters and CS provide further evidence for incorporating a HRV-guided training approach.

Intensity and duration of intermittent exercise and recovery during a soccer match.

Soccer is a sport consisting of high-intensity intermittent exercise, with players making forays across their anaerobic threshold for tactical advantage followed by periods of recovery. The intensity and duration of these work and recovery bouts were defined during a men's soccer match using StepWatch Activity Monitors recording step rate for each 3-second period. The data were coded by custom software to separate work bouts (step rate ≥ 4) from recovery bouts (step rate < 4), and a square wave of the pattern of bouts was plotted for 5 players: center forward, central midfielder, wing midfielder, central defender, and wing defender. Four values were calculated for each work and recovery bout identified: duration, and mean, maximum, and minimum step rate (intensity). This novel technique provided detailed graphical information on the duration and exercise intensity of each position throughout the match. The center midfielder was able to sustain work and recovery bout characteristics throughout the match and appeared to recover at higher intensity levels than other players. The forward showed the consequence of accumulated fatigue late in the match and was unable to sustain the duration of high-intensity work bouts observed earlier in the match. The central defender attenuated the intensity of his work and recovery bouts late in the match staying closer to a more moderate work rate with fewer high- or low-intensity bouts. Having objective data qualifying players' work and recovery bout characteristics might prove valuable for tactical decision making, substitution timing, and for planning future training sessions.

Fungal infections in corn picker hand injury.

INTRODUCTION: Hand injuries caused by corn pickers are relatively rare but in most cases extensive, with massive tissue destruction. Severe wounds sustained during agricultural work are contaminated, with high incidence of infection. OBJECTIVE: The aim of the study was to determine the frequency and type of fungal infection in corn picker injuries and their impact on the course and outcome of treatment. METHODS: Corn picker hand injuries for the period 2006-2012 were analyzed. After setting up clinical suspicion, direct examination of repeated swabs and histopathological analysis of biopsy material were done in order to detect fungi. RESULTS: From the total number of 60 patients, there was a fungal infection in nine of them (which makes 15% of the total number of patients). Aspergillus spp. was isolated in seven patients, Candida spp. in three, and Mucor spp. in one patient. None of the patients had increased risk factors for developing a fungal infection. In most cases, there was loss of graft and tissue necrosis in previously normally look- ing wound, after seven or more days. All patients were treated with repeated surgical debridement and concomitant parenteral and topical application of appropriate antifungal agents. There was no need for reamputation in any patient. CONCLUSION: A high degree of suspicion and a multidisciplinary approach are needed for early diagnosis of fungal infection. Confirmation of diagnosis and the initiation of surgical and appropriate antifungal therapy are essential for a successful outcome.

Single stage surgical treatment of amniotic band syndrome ­ Case report.

Introduction: Amniotic band syndrome is a rare congenital disorder with clinical presentation of constricting bands in different parts of extremities or whole extremities. Conservative or surgical treatment is provided depending on the type and severity of the anomaly. Case Outline: The paper presents the case of a neonate patient with constriction bands localized on the left leg. During the second week of life, a surgery was indicated, and a single-stage multiple Z-plasty was performed to correct the anomalies on the left lower leg. Postoperative edema in the distal part of the lower leg was easily managed by incisions and drainage. Two months later, the correction of the stricture of the left thigh was managed using the same procedure. The postoperative course was uneventful and the outcome was satisfactory after a two-year follow-up. Conclusion: Evaluation of a patient with amniotic band syndrome, as well as diagnosis, monitoring, treatment and postoperative care, should always be multidisciplinary. A single-stage correction approach provided satisfactory both functional and aesthetic results. Given many morphological variations of the syndrome, a decision on the strategy of treatment should be made individually for each patient.

PYODERMA GANGRENOSUM IN BURNED PATIENT - CASE REPORT.

INTRODUCTION: Pyoderma gangrenosum is a rare, chronic, destructive, ulcerating skin disease of uncertain etiology. It develops most frequently in patients between 25-45 years of age and affects both sexes equally. CASE REPORT: We present a case of pyoderma gangrenosum in a young female patient who sustained a burn injury of 40% total body surface area. She underwent four operations. She developed a wound infection and urinary infection during her hospital stay. By the end of hospitalization, the papules followed with coalesce of ulcerations formed on the previously epithelized areas of her legs. The patient complained of the intensive pain localized on these surfaces. Since pyoderma gangrenosum was suspected, a dermatologist was included in treatment. Therapy was initiated (methylprednisolone 60 mg per day intravenously) with gradual reduction of the dosage. The patient was discharged from hospital two weeks later with almost fully complete cicatrization and epithelization. CONCLUSION: Pyoderma gangrenosum is still difficult to be diagnosed in the absence of specific and sensitive diagnostic methods; however, it is crucial to be suspected as early as possible and to start treatment immediately. Multidisciplinary approach is essential for ontimal results.

Mixed fungal infection (Aspergillus, mucor, and Candida) of severe hand injury.

Severe hand injuries are almost always heavily contaminated and hence wound infections in those patients are frequent. Fungal wound infections are rare in immunocompetent patients. A case of mixed fungal infection (Aspergillus, Mucor, and Candida) was documented in a young male patient, with a severe hand injury caused by a corn picker. The diagnosis of fungal infection was confirmed microbiologically and histopathologically. The treatment was conducted with repeated surgical necrectomy and administration of antifungal drugs according to the antimycogram. After ten weeks the patient was successfully cured. The aggressive nature of Mucor and Aspergillus skin infection was described. A high degree of suspicion and a multidisciplinary approach are necessary for an early diagnosis and the initiation of the adequate treatment. Early detection, surgical intervention, and appropriate antifungal therapy are essential in the treatment of this rare infection that could potentially lead to loss of limbs or even death.

[Principles of management of high-energy injuries of the leg]. / Principi zbrinjavanja visokoenergetskih povreda potkolenice.

INTRODUCTION: High-energy traumas are open or closed injuries caused by force (missile, traffic injuries, crush or blust injuries, falling from heights), affecting the body surface and transferring high amount of kinetic energy inducing great damage to the tissue. Management of such lower extremity injuries has evolved over past several decades, but still remains a difficult task for every surgical team. Specific anatomic and functional characteristics combined with extensive injuries demands specific treatment protocols. MULTIPLE INJURIES: In a multiple injured patient the first priority is management of life-threatening trauma. Despite other injuries, surgical treatment of limb-threatening injuries must start as soon as life-threatening condition has been managed. TREATMENT ALGORITHMS: Algorithms are especially beneficial in management of severely injured, but salvageable extremities and in making decision on amputation. Insight into mechanisms of injury, as well as systematic examination of the affected limb, should help us understand the extensiveness of trauma and make an adequate management plan. PREVENTION OF INFECTION AND SURGICAL APPROACH: Prevention of wound infection and surgical approach to high-energy limb trauma, which includes wound extension, wound excision, skeletal stabilization and if necessary muscle compartment release, should be done in the first 6 hours after injury. METHODS OF SOFT TISSUE RECONSTRUCTION: Commonly used methods for soft tissue defects must provide wound coverage in less than five days following injury. REHABILITATION: Early passive and active mobilization and verticalization of patients is very important for successful treatment. CONCLUSION: Good and timely evaluation of the injured and collaboration between plastic and orthopaedic surgeons from the beginning of treatment, are crucial for final outcome.

[Some considerations on evaluation of the acutely limping child]. / Neka zapazanja o evaluaciji akutnog hramanja kod deteta.

INTRODUCTION: An acute limp implies an underlying pathology that causes disruption of the standard gait pattern. DIAGNOSIS AND HISTORY OF DISEASE: The differential diagnosis of a limp includes trauma, infection neoplasia, inflammatory, congenital, neuromuscular or developmental disorders. History of disease and clinical examination present first steps in adequate evaluation. A useful approach is to consider the causes of limping from head to foot to avoid overlooking common underlying conditions. The age of patient can further narrow the differential diagnosis, because certain disease entities are age-specific. LABORATORY ANALYSIS: Laboratory analysis should always include complete blood count, erythrocyte sedimetation rate, C-reactive protein, rheumatic factor, PPD 3. In some cases we have to perform tests of enzyme values such as alkaline phosphatase, lactate dehydrogenase, and other subspecial analyses in order to exclude some systemic and autoimmune diseases. RADIOLOGIC DIAGNOSIS: Radiologic diagnosis should include: ultrasonography (doppler ultrasonography and in some cases, arteriography); Plain films (always anteroposterior (AP) and profile or some special angle); computed tomography, magnetic resonance imaging. CONCLUSION: In this paper we suggested an algorithm for examination of a limping child: 1. Analysis of foot morphology and the gait without socks and shoes. 2. Strength test including walking on toes and heels and running. 3. Evaluation of arthritis, stiffness, pain, skin changes. 4. Points of a maximum pain with ROM testing. 5. Traces of trauma with echimosis. 6. Evaluation of leg length discrepancy. 7. Muscle tonus. 8. Abdominal examination 9. Examination of the spine and back.