ESTIMATED PATELLOFEMORAL COMPRESSIVE FORCES AND CONTACT PRESSURES DURING DANCE LANDINGS

Patellofemoral dysfunctions due to abnormal force loading are signific ant problems for dancers. Increased jump length was predicted to requi re increased quadriceps force during landing, which would increase pat ellofemoral forces and pressures. Six female dancers performed 10 trav eling jumps each at 30, 60, and 90% maximum jump displacements (JDs). A sagittal view of the landing onto a force platform (500 Hz) was film ed (100 fps). Repeated-measures ANOVA (JD) and Scheffe post hoc analys es (p < .05) showed that greater peak patellofemoral pressures occurre d at longer JDs and the corresponding times to these events decreased and knee flexion increased. Previous research and these findings indic ate that different regions of the patella may endure higher loads at g reater JDs even though the contact areas increase with greater patello femoral forces. However, greater knee flexion and velocity could indic ate more rapid distribution of load to various patellar regions, which would reduce the time any given patellofemoral region would be subjec ted to high loads.