Drop-jump landing performance linked with risk for ankle sprains in male soccer players

Michael J. Mullaney , DPT, SCS

Fransz and colleagues should be commended for their efforts in adding another prospective study to the field of injury prediction of ankle sprains. They were successfully able to correlate mediolateral stability and horizontal ground reaction force between 3 and 5 seconds during a single-leg drop jump landing among individuals with ankle sprains, in elite junior soccer players. The authors had the young soccer players jump off a 20-cm height, step onto a single leg and stabilize for 15 seconds on a force plate. At this time, the force plate measured the varying ground reaction forces (GRF) associated with each lower extremity landing. This study appears to be a precursor to what would be a larger study to develop an intervention to address the flaws in the GRFs that were related to the associated ankle sprains.

One of the challenges of researching ankle sprains is the concept of contact vs. non-contact. Obviously, the mechanism of injury differs in these two concepts and should be noted. It appears in this study the authors did not delineate contact vs. non-contact injuries. It would have been interesting to see if the results would have been altered based on the mechanism of injury. The authors explain that although they did not find a previous ankle sprain was a risk factor, they noted that the greater the severity (time lost) of the ankle sprain, the greater the hazard ratio.

The researchers acknowledged that ankle sprains are multifactorial and that these GRFs may only be one component. However, multiple previous studies have shown that stability training programs can decrease ankle sprain incidence rates in various sports, including soccer. We look forward to the authors developing an intervention study in an effort to improve these GRFs and improve these risk factors.