2015 ISAKOS Biennial Congress ePoster #1103
Physiologic Posterolateral Corner Knee Laxity in Asymptomatic Soccer Athletes
Diane L. Dahm, MD, Rochester, MN UNITED STATES
Andrew J. Blackman, MD, Chesterfield, MO UNITED STATES
Paul L. Sousa, MBA, Rochester, MN UNITED STATES
David A. Krause, PT, DSc, Rochester, MN UNITED STATES
Bruce A. Levy, MD, Rochester, MN UNITED STATES
Mayo Clinic, Rochester, MN, USA
FDA Status Not Applicable
Summary: Experienced male soccer players have increased ER of their dominant compared to their non-dominant knee with dial test at 30° flexion.
Due to sidefoot kicking and increased genu varum compared to other athletes, soccer players may place increased stress on the posterolateral corner (PLC). This study aims to determine if asymptomatic soccer players have side-to-side asymmetry in PLC laxity and to correlate PLC laxity with lower extremity alignment.
Forty asymptomatic athletes with =10 years’ soccer experience underwent bilateral dial testing at 30° and 90° flexion. Intercondylar distance (ICD) was measured to determine lower extremity alignment. Dominant and non-dominant leg dial test results were compared and correlated with ICD measurements.
Dial testing demonstrated greater tibial ER at 30° flexion in the dominant leg than the non-dominant leg in males (35.6° vs 32.4°, p = 0.02) but not females (36.3° vs 33.7°, p = 0.13). Tibial ER was similar in the both legs at 90° flexion for males and females. 20% of males had >10° side-to-side dial test asymmetry at 30° flexion. Mean ICD for males and females was 16.75 (range, 0–55) mm and 3.5 (range, 0-25) mm, respectively (p < 0.01). ICD did not correlate with dial test results.
Experienced male soccer players have increased ER of their dominant compared to their non-dominant knee with dial test at 30° flexion. Males demonstrated significantly more varus knee alignment than females; however, this did not correlate with dial test results. The average amount of ER asymmetry (3°) is not likely clinically significant. However, >10° side-to-side asymmetry was not uncommon (20% of male subjects).
CLINICAL RELEVANCE: The findings of this study suggest male soccer players have side-to-side asymmetry in the physiologic laxity of the PLC, which may mimic PLC insufficiency in the setting of a knee injury.