The pilot reported making an approach to land in light winds. The balloon skipped once and then made a slightly heavier than normal landing after brushing through a small tree. A female passenger complained of injury while still in the basket after landing. The balloon was deflated and the injured passenger was left in the basket for the trip to the hospital. A later report revealed that the passenger had suffered tibial plateau fractures to both legs. Witnesses and other passengers made no adverse comments about the severity of the landing. The injured passenger was wearing suitable footwear, but may have assumed an incorrect position when bracing for the landing.