The Effects of Ice Hockey Goaltender Leg Pads on Safety and Performance

Ice hockey goaltenders have the highest percentage of cam-type femoroacetabular impingement (FAI). The exact cause of these injuries in goaltenders remains unknown; however, it has been suggested that common goaltender movements and a goaltender’s underlying hip pathology may be contributing factors. The butterfly save technique, commonly used by goaltenders, has been linked to FAI. Simply stopping these movements would likely be detrimental to goaltender performance. Therefore, changing other aspects of goaltending, such as altering the goaltender equipment, should be considered. The overall objective of this thesis was to understand how ice hockey goaltender leg pads influence both the safety and performance of goaltenders. This was achieved through three projects: quantifying the effect of varying goal pad styles and modifications on goaltender hip kinematics, quantifying goal pad kinematics with respect to the goaltender’s body, and quantifying interface forces between the goaltender and their equipment to understand the biomechanical interactions. A new kinematic marker set and a novel interface force research protocol were developed in Chapters 2 and 4, respectively. Chapter 2 identified that, on average, 64% of goaltenders exceeded their active internal rotation range of motion limit during butterfly movements. Butterfly hip kinematics were not altered in four different styles of goal pad (Chapter 2). However, in Chapter 2 and 3 performance differences were observed between the four goal pad conditions, suggesting that a flexible-tight goal pad will produce the fastest butterfly drop velocity and butterfly width without statistically altering hip kinematics. In Chapter 4, there were no interface force differences between a stiff-wide and a flexible-tight goal pad condition; however, peak medial ice contact forces averaged 1073.8 N and 1221.8 N, respectively. These ice contact forces combined with compromising hip kinematics may increase a goaltender’s risk of developing FAI. Therefore, understanding the biomechanical interactions between a goaltender’s equipment and their body will help manufacturer’s develop equipment that minimizes hip kinematics and peak contact forces that can cause intra-articular hip injuries in goaltenders

Is intimate partner violence more common in pregnant women with severe mental illness? A retrospective study

Objective: To examine the risk of past and current experiences of intimate partner violence (IPV) in women with severe mental illness (SMI) in pregnancy. Methods: We examined past and current experiences of IPV in women with SMI in pregnancy. The data of 304 women with SMI including schizophrenia and related psychotic disorders and Bipolar Disorder meeting International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification (ICD-10-AM) criteria were extracted from hospital records at King Edward Memorial Hospital, Western Australia. Comparisons were made between our study data and the Australian population data reported by the Australian Bureau of Statistics, which included data on pregnant women in Western Australia. Additional measures included reported demographics, substance use and pregnancy variables. Results: Around 48% of pregnant women with SMI had experienced IPV and were three times the risk when compared with the general pregnant population in Australia. There was no difference in rates of IPV in those women with psychotic disorders when compared with bipolar disorder. Furthermore, the rates of smoking and illicit substance use were significantly higher in pregnant women with SMI who experienced IPV compared with those who have not experienced IPV. Conclusion: These findings suggest women with SMI in pregnancy are at significantly higher risk of having experienced or experiencing IPV. In addition, IPV in pregnant women with SMI may increase the risk of smoking and illicit substance use. Together this suggests that maternity and mental health services should ensure there are both screening and support pathways for IPV that are developed and evaluated specifically for pregnant women with SMI

DEVELOPMENT OF A PROTOTYPE SMART APPAREL TO QUANTIFY RUNNING GAIT IN THE DAILY TRAINING ENVIRONMENT

Running gait kinetics and kinematics can be measured in the lab using force-instrumented treadmills and 3D motion capture. However, these tools are not feasible for use in the daily training environment of recreational and elite runners and track athletes. An inertial sensor-based prototype wearable smart garment (SG) has been developed to solve this problem. The purpose of this study was an initial assessment of SG compared to a force treadmill (FT) where foot-ground kinetics and temporal measures relevant to running were examined. Vertical ground reaction force, step time, and contact time showed “good to excellent” mean absolute percent error (\u3c 6%), while step impulse did not (\u3e 10%). All variables showed strong correlations between SG and FT (r \u3e 0.85). The initial prototype smart garment is a viable option for the measurement of running biomechanics outside of the lab

SPRINT KAYAKER’S KINETIC ASYMMETRIES AT INCREASING STROKE RATES

Kinetic movement asymmetries are known to affect factors of performance, increase the likelihood of injury, and to decrease with increased cadences. The aim of this study was to determine if stroke rate affects asymmetry indexes (ASI) in the kayak ergometer footboards and seat. A significant main effect of stroke rate was found on footboard mediolateral total stroke cycle impulse (TSI) ASI (p\u3c0.005) where asymmetry index increased with stroke rate, footboard anteroposterior TSI ASI (p\u3c0.005) where an inverted U-shaped relationship was found with stroke rate, and footboard roll total stroke cycle angular impulse (TSAI) ASI (p\u3c0.001) where an inverted U-shaped relationship was found with stroke rate, and seat mediolateral TSI ASI (p\u3c0.05) where it decreased with stroke rate. The results of this study show that footboard and seat lateral forces counteract each other

FOOTBOARD AND SEAT KINETIC CHANGES ASSOCIATED WITH STROKE RATE ON A KAYAK ERGOMETER

The purpose of this study was to determine if stroke rate effects anteroposterior, lateral, and vertical forces on the kayak’s footboard and seat. Participants (n=10), with a year or more of competitive kayaking experience, completed four 30-second trials on a kayak ergometer at different stroke rates (60 strokes per minute (spm), 80 spm, 100 spm, and maximum spm). Mean force, impulse, and impulse*stroke rate were identified for the footboards, and seat, separately within each trial (ten single strokes). Interestingly, both anteroposterior and lateral axes kinetic adaptations to stroke rate occurred on the left footboard whereas the right footboard presented only lateral adaptations

Pregnancy experiences of Western Australian women attending a specialist childbirth and mental illness antenatal clinic

Our purpose was to explore the pregnancy experiences of Australian women attending a specialized Childbirth and Mental Illness (CAMI) antenatal clinic. A qualitative exploratory design was selected to give voice to women with a severe mental illness receiving antenatal care. Telephone interviews with 41 women, 24 primiparous and 17 multiparous, were analysed using thematic analysis. Three themes emerged: ‘Building relationships’, ‘Acknowledged me as a person with special needs’ and ‘Respect and understanding without stigma’. Findings offer insight into care experiences possible within a multidisciplinary model developed to addresses psychiatric and obstetric needs of pregnant women with severe mental illness

Minimally-invasive debulking of ovarian cancer in the rat pelvis by means of photodynamic therapy using the pegylated photosensitizer PEG-m-THPC

Interstitial photodynamic therapy (PDT) using the pegylated photosensitizer PEG-m-THPC was evaluated as a minimally-invasive procedure to selectively debulk unrespectable pelvic ovarian cancer (NuTu-19) in immunocompetent rats. To assess tumour selectivity, PEG-m-THPC at dosages of 0.3, 3.0 and 30 mg kg−1 body weight was administered intravenously to 30 rats 4 weeks following tumour induction. Eight days later laser light at 652 nm and optical doses ranging from 100 to 900 J cm−1 diffuser-length was delivered by an interstitial cylindrical diffusing fibre inserted blindly into the pelvis. Three days following light application, the volume of necrosis was measured and the damage to pelvic organs was assessed histologically on cross sections. For analysis of survival, 20 tumour-bearing rats received PDT using drug doses of 3 or 9 mg kg−1 body weight and an optical dose of 900 J cm−1 diffuser-length, whereas ten untreated tumour-bearing rats served as controls. The histological assessment of PDT induced necrosis showed a non-linear dose–response for both the photosensitizer dose and the optical dose. The lowest drug dose activated with the highest optical dose did not induce more necrosis than seen in tumour-bearing control animals. The same optical dose induced necrosis of 17 mm in diameter using 30 mg kg−1 and 11 mm using 3 mg kg−1 photosensitizer. The optical threshold for induction of significant necrosis was between 100 and 300 J cm−1 diffuser-length for 30 mg kg−1 and between 300 and 500 J cm−1 for 3 mg kg−1 PEG-m-THPC. Significant damage to normal pelvic organs was only seen if 30 mg kg−1 photosensitizer was activated with optical doses of 700 J cm−1 or more. In the survival study, all treated animals survived PDT for at least 2 weeks and the intestinal and urinary tract remained functional. No clinical signs of blood vessel or nerve injury were observed. Mean overall survival of untreated tumour-bearing rats was 25.0 ± 4.5 days compared to 38.4 ± 3.8 days and 40.0 ± 3.6 days for rats treated with 3 mg kg−1 or 9 mg kg−1 PEG-m-THPC mediated PDT respectively (P < 0.05). We conclude that PEG-m-THPC mediated PDT has a favourable therapeutic window and that this minimally-invasive procedure can reduce pelvic cancer bulks effectively and selectively. © 1999 Cancer Research Campaig

Chemical modeling for pH prediction of acidified musts with gypsum and tartaric acid in warm regions

Winemaking of musts acidified with up to 3 g/L of gypsum (CaSO4 2H2O) and tartaric acid, both individually and in combination, as well as a chemical modeling have been carried out to study the behaviour of these compounds as acidifiers. Prior to fermentation gypsum and tartaric acid reduce the pH by 0.12 and 0.17 pH units/g/L, respectively, but while gypsum does not increase the total acidity and reduces buffering power, tartaric acid shows the opposite behaviour. When these compounds were used in combination, the doses of tartaric acid necessary to reach a suitable pH were reduced. Calcium concentrations increase considerably in gypsum-acidified must, although they fell markedly after fermentation over time. Sulfate concentrations also increased, although with doses of 2 g/L they were lower than the maximum permitted level (2.5 g/L). Chemical modeling gave good results and the errors in pH predictions were less than 5% in almost all case