The ‘jumpers knee paradox,’

The ‘jumpers knee paradox,’ where symptomatic athletes appear to perform better in measures of vertical jump height compared to asymptomatic individuals, has not been thoroughly explored. The aim of the current study was to investigate whether jumping ability and change of jumping ability may predispose an athlete to the onset of jumper’s knee [A&P: patellar tendinitis]. 

150 elite volleyball players were followed prospectively over a 5-year period. Vertical jump height –determined via counter movement jump (CMJ) and standing jump (SJ) – was assessed at the time of inclusion and semiannually. 28 athletes developed jumper’s knee over this period. Retrospective analysis revealed that symptomatic male athletes performed significantly better in CMJ compared with asymptomatic males at the time of inclusion, while no differences were detected in SJ. All athletes improved their jump performance over the duration of the study, with no significant differences observed in change in jump ability between symptomatic and asymptomatic athletes. 

These findings suggest that male volleyball players who naturally jump high are at greater risk at developing jumper’s knee, independent of subsequent improvements in jumping skills resulting from higher training loads > Visnes et al.; Br J Sports Med. (2012). All rights reserved to BJSM.