Patient case (clinical description): A 19-year-old girl comes to the clinic due to a left wrist mass.  She noticed swelling on the top of her wrist about 4 months ago and came to the clinic due to cosmetic concerns.  Examination shows a nontender, rounded mass on the dorsal wrist that transilluminates with a penlight. Vital signs are normal. The patient needs to type on her computer almost all day. She is left-handed. She does not smoke or use illicit drugs. She is in sexual relationship with two male partners and uses condoms.

Patient's own account: I'm a 19-year-old girl and I went to see my doctor because of a mass on my left wrist. I noticed a swelling on top of my wrist, like 4 months ago, and I went the first time to the doctor because it was pretty ugly! My wrist was not tender, and the mass was round and let the light go through when the doctor used a penlight. My blood pressure, breathing and temperature were normal. I'm left-handed and I need to be on my PC all day. I don't smoke or do drugs. I'm sexually active and I have 2 male partners but they all use condoms.

Clinical trial: Fat Mediated Modulation of Reproductive and Endocrine Function in Young Athletes

Eligibility criteria:
Inclusion Criteria:

          -  Females 14-21 years old Note: Our pilot data are reassuring in that young women 18-25
             years old with hypothalamic amenorrhea are not adversely affected with estrogen use.
             In fact, in our prospective study, beneficial effects were observed both in young
             women 18-25 years old using oral estrogen, and in 14-18 year old adolescent girls
             using transdermal estrogen. We therefore feel that including girls in the 14-21 year
             age range will not be hazardous to their bone health. In fact, given the lack of data
             in this age group, it is important to study younger women and teenagers rather than
             extrapolate data from studies in adults to this younger population. Hormone dynamics
             differ in teenagers compared with adults, and bone mass accrual is even more dependent
             on estrogen and IGF-1 in younger than older women who have already achieved peak bone
             mass.

          -  Bone age (BA) >15 years Note: 99% of adult height is achieved at a BA of 15 years,
             thus estrogen replacement will not result in stunting of height potential after this
             age. Although we could have chosen to include girls with a BA >14 in this study, we
             are limiting this to girls with a BA of >15 years. This is because 2% of growth
             potential persists at a BA of 14 years, versus only 1% at a BA of 15 years (~0.6" of
             potential height (130)). Thus, to avoid potential stunting of growth potential with
             estrogen replacement, we have chosen to include girls with BA of > 15 years.

          -  BMI between 10th-90th percentiles for age.

          -  Amenorrhea (for AA): absence of menses for > three months (74) within a period of
             oligomenorrhea (cycle length > six weeks) for >six months, or absence of menarche at
             >16 years.

          -  Eumenorrhea (EA and controls): > nine menses (cycle length 21-35 days) in preceding
             year.

          -  Non-athlete healthy controls will be eligible if weight bearing exercise activity is
             less than two hours a week and if they are not participating in organized team sports.

          -  Endurance athletes Note: severity of low BMD and menstrual dysfunction differ by kind
             of exercise and activity. For example, runners have a higher prevalence of menstrual
             irregularity than swimmers and cyclists (131). By limiting enrollment to endurance
             athletes, we will eliminate variability from the type of activity. Endurance training
             is defined as > 4 h of aerobic weight-bearing training of the legs or specific
             endurance training weekly, or > 20 miles of running weekly for a period of > 6 months
             in the last year.

        Exclusion Criteria:

          -  Other conditions that may affect bone metabolism
Female
Accepts Healthy Volunteers
Subject must be at least 14 Years old.
Subject must be at most 21 Years

Eligibility (NLI label): Contradiction