Affiliations: [a] Department of Rehabilitation and Functional
Evaluation, Fraternidad Muprespa Central Hospital, Madrid, Spain | [b] Department of Traumatology and Orthopaedics,
Fraternidad Muprespa Central Hospital, Madrid, Spain | [c] Real Madrid CF Medical Service, Madrid, Spain
Note: [] Address for correspondence: Dr. Jesús Olmo, Department of
Rehabilitation and Functional Evaluation, Fraternidad Muprespa, Madre de Dios
42, 28016 Madrid, Spain. Tel.: +34 913531179; Fax: +34 913431999; E-mail:
jolmo@fraternidad.com
Abstract: Patellofemoral pain (PFP) appears in actions that increase
patellofemoral compressive forces such as forceful quadriceps contraction in a
flexed knee position. PFP has been associated with quadriceps strength decrease
and disturbances ('breaks') in the torque-angular position. Twenty two active
high-level soccer players with PFP and breaks in the quadriceps isokinetic
curve were studied. The results showed that the quadriceps strength was
significantly reduced in comparison with the uninvolved side, being more
affected at flexed angles of the knee. A single break in the quadriceps
torque-angular position curve started on average at 73 ±
7° reaching the maximum break at 65 ± 7° and recovering at 54 ±
9°. At the minimal within-break torque
angle the average reduction was 30.6% while the PT was reduced by 18.4%.
Sub-clinical PFP in high-level soccer players may be related to a significant
loss in quadriceps muscular performance in the first part of knee extension
possibly affecting common soccer tasks such as kicking, jumping or tackling.
Isokinetic concentric testing may be used to detect and characterize this
alteration.
