Kenji Akashi was taken to a hospital in an ambulance on February 27 because of back pain. Akashi skipped workouts before a practice game against Lotte because of issues with his lower back. He was planning to leave the stadium during the game, but the condition of his back got worse and he was unable to walk. He was later taken to a hospital in Miyazaki and diagnosed with acute lower back pain.
[UPDATE 3/3 @ 3:15am]
The Softbank Hawks announced on March 2 that Akashi was discharged from the hospital.
Source: Nikkan Sports 3/2/2018