An observational study in Femoroacetabular Impingement, sponsored by McMaster University. Completed at 4 sites in 3 countries. Open to participants aged 12 Years to 14 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-07.
Sponsored by McMaster University · Observational
Femoroacetabular impingement (FAI) is a condition of the hip where there is a mis-fit between the femoral head (ball) and hip acetabulum (socket). The abnormalities on the hip bones collide or "impinge" during movements such as hip flexion and rotation. Typically, patients with this condition are young adults who present with hip pain, loss of hip function, and in many cases, osteoarthritis later in life. The rate of diagnoses of FAI has dramatically risen across all age groups, but it has been especially notable within adolescent populations. There has been a corresponding increase in the number of surgeries performed on younger and younger hips to treat pain and loss of function due to this condition. Preliminary small-scale research has hypothesized that increased activity, such as sport specialization (i.e. playing only one sport for most of the year) at an early age when the hip is still developing, may be the cause. In the past 20 years, sport injuries among children have dramatically increased, where close to 45 million young athletes participate in organized sports annually in Canada and the US alone. There is a current trend among coaches and parents to have children focus on one sport with the thought that this dedication will allow them to reach an elite level. We are proposing the first international, longitudinal cohort study to determine the effect of sport specialization on the development of FAI during the critical phase of hip development (i.e. between the ages of 12-14 years). Volunteer participants will be recruited across Canada and internationally and will be evaluated clinically and radiographically (i.e. using MRI) over 2 years. This study will not only prospectively evaluate the role of sport activity the development of FAI, but also inform preventative training protocols to potentially reduce its incidence among adolescents, and later as adults, as well as identify parameters to detect hips that are at risk for developing FAI.
This is a multi-centre, international longitudinal cohort study evaluating 200 participants between the ages of 12-14 that include sport specialists at the moderate to vigorous physical activity (MVPA) level and non-sport specialists at any activity level. Participant groups will be defined according to the AOSSM and AMSSM early sport specialization criteria (2016). We will monitor physical activity levels of all participants using an activity log and a wrist-mounted activity tracker, with synced data collected every 3 months during the study period. In addition, participants will be evaluated clinically and radiographically at time of enrollment and 6, 12, 18, and 24 months. The primary study outcome is the incidence of FAI between groups at 2 years, determined via MRI. Secondary outcomes include hip function and health-related quality of life between subjects diagnosed with FAI versus no FAI at 2 years, as determined by the HOS and PedsQL questionnaires.
108 studies on the registry are indexed under Femoracetabular Impingement; 35 are open to participants now.
This study's enrollment of 201 is above the median of 89 across 36 observational studies indexed under Femoracetabular Impingement.
Browse Femoracetabular Impingement studies →McMaster University is the lead sponsor of 720 studies on the registry; 124 are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 2 (33%) have results posted.
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The study population will be comprised of adolescents aged 12-14 with no prior or ongoing hip comorbidities, and consent to receiving MRI scans at baseline and 2 years.
Exclusion Criteria:
AOSSM Criteria: 1. Participation in intensive training and/or competition in organized sports greater than 8 months per year (essentially year round) 2. Participation in 1 sport to the exclusion of participation in other sports (limited free play overall) 3. Involving prepubertal (seventh grade or roughly age 12 years) children. AND Activity Tracker Criteria: Greater than 180 accumulated minutes of moderate-to-vigorous physical activity (MVPA) during participation in one sport type across one week of activity tracking \- Meets these criteria within either one or both years of follow-up
AOSSM Criteria: 1. Participation in more than 1 sport at any physical activity level OR 2. Participation in none or low training and/or competition in organized sports for any period of time. 3. Involving prepubertal children. AND Activity Tracker Criteria: Greater than or less than 180 accumulated minutes of MVPA across one week of activity tracking \- Meets these criteria during both years of follow-up
Incidence of radiographic FAI
The primary outcome is the incidence of radiographic FAI between groups at 2 years, as determined by the dedicated MRI of the hip. We will identify both symptomatic and asymptomatic cases, where asymptomatic FAI can become symptomatic in young adulthood, and/or could be associated with idiopathic osteoarthritis later in life.
Time frame: 2 years
Hip function
As determined by the Hip Outcome Score
Time frame: 2 years
Health-related quality of life
As determined by the Pediatric Quality of Life questionnaire
Time frame: 2 years
Plan to share: No
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is completed, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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