A pre-post performance comparison of the long head of the biceps brachii muscle oxygenation in young baseball pitchers.

AIM: The role of the long head of the biceps brachii (LHBB) is vital in maintaining stability of the glenohumeral joint during baseball pitching. Unfortunately the impact of extended pitching on the ability of the LHBB to maintain its function is not currently known. Thus, the purpose of this study was to examine the magnitude of muscle oxyhemoglobin saturation in the biceps brachii, indicated as tissue saturation index (TSI%), before and following an extended pitching performance. METHODS: Data describing the magnitude of TSI% in the long head of the biceps brachii (LHBB) were collected from 20 pitchers (12.5 ± 2.1 years; 151.2 ± 11 cm; 46.7 ± 11.4 kg). TSI% was determined using a wireless muscle oximeter based on near-infrared spectroscopy (NIRS). The oximeter utilized in this study measured oxy, de-oxy, and total hemoglobin as well as tissue saturation. RESULTS: Results revealed that at the conclusion of the simulated game, participants experienced an 11.8% decrease in TSI% at contraction onset (P<0.05), a 5.9% decrease in TSI% at contraction offset (P<0.05), but no difference in TSI% utilized throughout the 5 s isometric contraction. Participants demonstrated a 5.9% decrease in change score for TSI% following the conclusion of the simulated game which did not differ significantly when compared to the beginning of the simulated game (P>0.05). CONCLUSION: These results indicate that young pitchers are not at risk of decreased LHBB function due to lower TSI%. However, the observation of significantly lower levels associated with TSI% following the simulated game reveal that further study into these parameters is warranted in older pitchers as they commonly throw greater than 85 pitches.

A kinematic and kinetic analysis of drop landings in military boots.

OBJECTIVE: The purpose of this study was to examine knee valgus in drop landings during three different footwear conditions and to examine the ground reaction forces exhibited during the drop landing in the three different footwear conditions. METHODS: Sixteen male and female Reserve Officer Training Corps (ROTC) university undergraduate cadets (21 +/- 3 yrs, 79 +/- 12 kg, and 172 +/- 10 cm) volunteered to participate in the study. Kinematic data were collected while participants performed drop landings in three conditions: bare feet, tennis shoes, and issued military boots. RESULTS: Significant differences among footwear for ground reaction forces (bare feet: 1646 +/- 359%, tennis shoe: 1880 +/- 379%, boot: 1833 +/- 438%; p < 0.05) were found, while there was no significant difference in knee valgus among footwear. CONCLUSIONS: Though footwear conditions did not affect knee valgus, they did affect ground reaction forces. Participants in this study had yet to receive any military training on how to land properly from a specified height. Further research should be completed to analyze the kinematics and kinetics of the lower extremity during different landing strategies implemented by trained military personnel in order to better understand injury mechanisms of drop landings in this population. It is likely that injury prevention landing techniques would be beneficial if these were employed by the military and not just in the sporting community.

Management of vaginal agenesis: review of 10 years practice at a tertiary referral centre.

Vaginal agenesis is an uncommon congenital anomaly, and is often associated with agenesis of the uterus and fallopian tubes. Recent reports suggest that non-surgical methods to create a neovagina offer advantages when assisted reproductive treatments are used in the adult life of these women. We have reviewed the management of 39 women with congenital vaginal agenesis to assess the outcomes of neovaginal creation. In 25 women with total Müllerian agenesis, creation of a neovagina using progressive perineal dilatation alone was very successful in women motivated by a sexual relationship.

MR imaging of paediatric uterovaginal anomalies.

BACKGROUND: Transabdominal ultrasound (US) has not proved completely reliable in Müllerian duct anomalies. One study has shown it useful in obstructed uterovaginal anomalies. We are unaware of a study that has used endovaginal ultrasound in children to investigate uterovaginal anomalies. Magnetic resonance imaging (MRI) is now gaining wide acceptance in imaging congenital abnormalities of the genital tract. OBJECTIVE: To identify the problems and potential pitfalls of using MRI to evaluate the female genital tract in paediatric patients. MATERIALS AND METHODS: A retrospective review of the MRI scans of 19 patients, aged 3 months to 19 years (mean 14 years), with uterovaginal anomalies. RESULTS: The uterovaginal anomalies were categorised into three groups: (1) congenital absence of the Müllerian ducts, or the Mayer-Rokitansky-Kuster-Hauser syndrome (n = 7), (2) disorders of vertical fusion (n = 2) and (3) disorders of lateral fusion (n = 10). CONCLUSIONS: MRI is a reliable method for evaluating paediatric uterovaginal anomalies, but should be analysed in conjunction with other imaging modalities (US and genitography). Previous surgery makes interpretation more difficult and, if possible, MRI should be carried out prior to any surgery. An accurate MRI examination can be extremely helpful prior to surgery and it is important for the radiologist to have knowledge of how these complex anomalies are managed and what pitfalls to avoid.

Experiment of nurture: ablatio penis at 2 months, sex reassignment at 7 months, and a psychosexual follow-up in young adulthood.

Guidelines of psychosexual management for infants born with physical intersex conditions are intended to assist physicians and parents in making decisions about sex of assignment and rearing including the following: 1) sex assignment should be to the gender that carries the best prognosis for good reproductive function, good sexual function, normal-looking external genitalia and physical appearance, and a stable gender identity; 2) the decision regarding sex assignment should be made as early as possible, preferably during the newborn period, with an upper age limit for reversal of an initial sex assignment no later than 18 to 24 months; and 3) there should be minimal uncertainty and ambiguity on the part of parents and professionals regarding the final decision about sex assignment and rearing. J. Money used these guidelines in a case of a biologically normal male infant (one of a pair of monozygotic twins) whose penis was accidentally ablated during a circumcision at the age of 7 months. The decision to reassign the infant boy to the female sex and to rear him as a girl was made at 17 months, with surgical castration and initial genital reconstruction occurring at 21 months. Money reported follow-up data on this child through the age of 9 years. Although the girl was described as having many "tomboyish" behavioral traits, a female gender identity had apparently differentiated. Thus, it was concluded that gender identity is sufficiently incompletely differentiated at birth as to permit successful assignment of a genetic male as a girl, in keeping with the experiences of rearing. Subsequent follow-up by other investigators reported that by early adolescence the patient had rejected the female identity and began to live as a male at the age of 14 years. In adulthood, the patient recalled that he had never felt comfortable as a girl, and his mother reported similar recollections. At age 25, the patient married a woman and adopted her children. The patient reported exclusive sexual attraction to females. The present case report is a long-term psychosexual follow-up on a second case of ablatio penis in a 46 XY male. During an electrocautery circumcision at the age of 2 months, the patient sustained a burn of the skin of the entire penile shaft, and the penis eventually sloughed off. At age 7 months, the remainder of the penis and the testes were removed. By age 7 months, if not earlier, the decision was made to reassign the patient as a female and to raise the infant as a girl. The patient was interviewed on two occasions: at 16 years and twice while in the hospital for additional surgery at 26 years of age. At ages 16 and 26, the patient was living socially as a woman and denied any uncertainty about being a female. During childhood, the patient recalled that she self-identified as a "tomboy" and enjoyed stereotypically masculine toys and games; however, the patient also recalled that her favorite playmates were usually girls and that her best friend was always a girl. When seen at age 16, the patient had been admitted to the hospital for vaginoplasty. At that time, she wished to proceed with the further repair of her genitalia to make them suitable for sexual intercourse with males. At age 26, the patient returned to the hospital for further vaginoplasty. Regarding the patient's sexual orientation, she was attracted predominantly to women in fantasy, but had had sexual experiences with both women and men. At the time of the second surgery, she was in a relationship with a man and wished to be able to have intercourse. The patient's self-described sexual identity was "bisexual." After surgery at age 26 years, the patient developed a rectovaginal fistula. Within a few months of the surgery, the patient and her male partner separated for reasons other than the patient's physical problems. The patient subsequently began living with a new partner, a woman, in a lesbian relationship. The psychosexual development of our patient was bot the other patient was married to a woman. Our patient had a "bisexual" sexual identity; the other patient had a "heterosexual" sexual identity. The patients were similar in that they had a childhood history of "tomboyism." Our patient was predominantly sexually attracted to women; the other patient was exclusively sexually attracted to women. Our patient had sexual experiences with both women and men; the other patient had sexual experiences only with women. The most plausible explanation of our patient's differentiation of a female gender identity is that sex of rearing as a female, beginning at around age 7 months, overrode any putative influences of a normal prenatal masculine sexual biology. Because cases of ablatio penis in infancy are so rare and long-term follow-up data are scant, it is obviously impossible to know whether our patient or the previous case would be more typical of the psychosexual outcome in a larger sample of such individuals. However, our case suggests that it is possible for a female gender identity to differentiate in a biologically "normal" genetic male. At present, however, the clinical literature is deeply divided on the best way to manage cases of traumatic loss of the penis during infancy. Further study is clearly required to decide on the optimal model of psychosocial and psychosexual management for affected individuals.

Outcome of ovum donation in Turner's syndrome patients.

OBJECTIVE: To determine whether there is a difference in the pregnancy rate in women with Turner's syndrome (45,X) in an ovum donation program compared with women with other causes of premature ovarian failure. DESIGN: Retrospective chart review of women with Turner's syndrome (n = 11) and premature ovarian failure (n = 38) in a donor ovum program using variable dose and duration of E2 replacement therapy for endometrial preparation and using only transvaginal ultrasonographic assessment of endometrial response before ET. RESULTS: The pregnancy rates in Turner's syndrome patients and control subjects were 27% and 25%, respectively. Pregnancy rates were higher in the first cycle than in subsequent cycles for both groups (40% versus 8%). CONCLUSIONS: Turner's syndrome patients given a variable dose of estrogen, for endometrial preparation, with response assessed exclusively by transvaginal ultrasonography demonstrated pregnancy rates equal to patients with other causes of premature ovarian failure.

Stereo-photogrammetry for the determination of patient surface geometry.

A stereo-photographic system has been developed with which surface contours of a human subject may be obtained rapidly and objectively. Nonmetric cameras are used and the results are obtained from direct measurements of the photographs. Software has been developed for interpretation of the photographic data with the assistance of a small computer and desk-top digitizer such as those routinely used in radiotherapy treatment planning. With the system the coordinates of a point on the subject may be determined with an accuracy of +/- 1-2 mm.

A method of increasing the linear activity of 192Ir sources for interstitial implantation.

The authors suggest that low-intensity 129Ir wires be twisted together to increase linear activity and dose rate for interstitial implantation. This technique saves time and expense for the patient and reduces radiation to personnel.

Photon and electron response of silicon-diode neutron detectors.

The photon response of silicon-diode neutron detectors is analyzed theoretically and measured in the 15-25-MeV region. The main mechanism for producing a response in the diode is shown to be the displacement of silicon atoms by scattering of electrons. If the photon source is an electron accelerator target, the response is mostly due to electrons originating in the target with a smaller contribution from electrons produced in the diode by photons generated at small angles to the beam.

"Measurements of surface dose using build-up curves" obtained with an extrapolation chamber.

Surface dose was measured in an extrapolation chamber and was found to be less than previously reported. The slope of the build-up curve was less steep with the Clinac 4 than with 60-Co and much steeper with the Clinac 35 at 25 MV than with the betatron at the same energy. The gradient of the depth-dose curve in the build-up region is probably the best indicator of skin damage.

Build-up region of megavoltage photon radiation sources.

Measurements of surface dose and build-up have been measured for photon radiation sources with maximum energy from 1.2 to 25 MeV. A variable volume ionization chamber was used and the results extrapolated to what would be obtained with a zero volume chamber. The results are found to depend systematically on the plate separation of a parallel plate ionization chamber and an empirical method was derived for correcting measurements made with a fixed volume chamber. The relationship of dose build-up curves with skin reactions in radiation therapy patients is discussed.