Background Patellar malalignment reveals a inappropriate tendon traction and could lead to overuse injuries as patellar tendinopathy. There is two angles that describe the frontal patellar rotation: Arno (A) and McConnell (M). There is lack of evidence about the normative data, especially in jumping athletes.

Objective analyse the Arno and McConnell's patellar angles profile in jumping athletes.

Design observational cross-sectional.

Setting all testing occurred at Minas Tênis Club and at Sports Injury Prevention and Rehabilitation Laboratory – LAPREV.

Participants 171 volleyball, basketball and gymnastics athletes (41 female and 130 male) were assessed. All participants were healthy, with no current complaints of lower limb injury or pain and no history of previous lower extremity surgery. The average+SD age, height and mass of the athletes was 15.7+5.1 years, 178.2+14.5 cm, 68.3+16.5 Kg.

Assessment of risk factors Age, sex, body mass index (BMI) and sports modality were the independent variables.

Main outcome measurements frontal plane patellar rotation in stand position with 30° of knee flexion.

Results The means for M and A angles at dominant and non-dominant limbs were −0.87 (+4.75), −4.1 (+5.2), 4.6 (+7.34) and 1.35 (+8.1) degrees respectively. Statistic significant differences were found in AD and AnD limbs at female and male group (p=0.001), in MD at modalities female volleyball and male basketball (p=0.012), in AnD at ages between >19 and 7 to 10 (p=0.005), 11 to 14 (p=0.000) and 15 to 19 (p=0.006) and in AD between normal and low BMI groups.

Conclusion This study shows normative data about M and A angles in jumping athletes. Some associations were found between sex, age, sports modality and BMI with A angle and modality with M angle. These variables must be considered part of athletes' preseason assessment.