Serum and synovial fluid cytokine profiling in hip osteoarthritis: distinct from knee osteoarthritis and correlated with pain.

Background: Inflammation is associated with the onset and progression of osteoarthritis in multiple joints. It is well known that mechanical properties differ between different joints, however, it remains unknown if the inflammatory process is similar/distinct in patients with hip vs. knee OA.

Intraarticular and systemic inflammatory profiles may identify patients with osteoarthritis.

Objective: To determine whether cytokine/chemokine profiles from synovial fluid and sera discriminate mild/moderate osteoarthritis (OA) from normal and severe OA cohorts.

Methods: Multiplex technology was used to quantify expression levels for 42 cytokines in the synovial fluid of patients diagnosed with severe OA (n = 20) and mild/moderate OA (n = 12), as well as normal controls (n = 34). The same 42 cytokines were examined in serum samples of patients with severe OA (n = 26) and mild/moderate OA (n = 74) and normal individuals (n = 100).

Diminished cartilage-lubricating ability of human osteoarthritic synovial fluid deficient in proteoglycan 4: Restoration through proteoglycan 4 supplementation.

Objective: The purposes of this study were 1) to quantify the proteoglycan 4 (PRG4) and hyaluronan (HA) content in synovial fluid (SF) from normal donors and from patients with chronic osteoarthritis (OA) and 2) to assess the cartilage boundary-lubricating ability of PRG4-deficient OA SF as compared to that of normal SF, with and without supplementation with PRG4 and/or HA.

Methods: OA SF was aspirated from the knee joints of patients with symptomatic chronic knee OA prior to therapeutic injection. PRG4 concentrations were measured using a custom sandwich enzyme-linked immunosorbent assay (ELISA), and HA concentrations were measured using a commercially available ELISA.

Risk of injury associated with bodychecking experience among youth hockey players.

Background: In a previous prospective study, the risk of concussion and all injury was more than threefold higher among Pee Wee ice hockey players (ages 11-12 years) in a league that allows bodychecking than among those in a league that does not. We examined whether two years of bodychecking experience in Pee Wee influenced the risk of concussion and other injury among players in a Bantam league (ages 13-14) compared with Bantam players introduced to bodychecking for the first time at age 13.

Methods: We conducted a prospective cohort study involving hockey players aged 13-14 years in the top 30% of divisions of play in their leagues.

Risk of injury associated with body checking among youth ice hockey players.

Context: Ice hockey has one of the highest sport participation and injury rates in youth in Canada. Body checking is the predominant mechanism of injury in leagues in which it is permitted.

Objective: To determine if risk of injury and concussion differ for Pee Wee (ages 11-12 years) ice hockey players in a league in which body checking is permitted (Alberta, Canada) vs a league in which body checking is not permitted (Quebec, Canada).

A prevention strategy to reduce the incidence of injury in high school basketball: a cluster randomized controlled trial.

Objective: To examine the effectiveness of a sport-specific balance training program in reducing injury in adolescent basketball.

Design: Cluster randomized controlled trial.

Setting: Twenty-five high schools in Calgary and surrounding area.

Survey of sport participation and sport injury in Calgary and area high schools.

Objective: To examine (1) sport participation and (2) sport injury in adolescents.

Design, Setting, And Participants: This was a retrospective survey design. In total, 2873 adolescents were recruited from a random sample of classes from 24 Calgary and area high schools.