premise: A 59-year-old electronics company executive arrived in Osaka Friday to become the first of 24 Japanese hostages to return home after being held hostage for four months in the Japanese ambassador's residence in Lima.
  Shigeru Taki, the president of the Peruvian subsidiary of Osaka-based Matsushita Electric Industrial Corp., arrived at Kansai International Airport with his 60-year-old wife Tetsuyo.
  Confined to a wheelchair, Taki was greeted at the airport by his two daughters, aged 27 and 24, along with officials from Matsushita and the Japanese foreign ministry.
  Taki said he sprained his right ankle after jumping from the roof of the residence Tuesday when Peruvian troops stormed the compound, rescuing all but one of the 72 hostages and killing all 14 rebels.
  "I am home, free at last after 127 days of captivity," he told a news conference at an airport hotel, thanking the Peruvian and Japanese governments, the Red Cross and the panel of guarantors for their efforts to find a solution.
   How did Taki sprain his ankle?
hypothesis: jumping from the roof