Naomi Osaka shared about spending her birthday at the hospital during the ongoing Japan Open. The Japanese battled through injury to reach the quarterfinals round of the tournament on Wednesday.Osaka's latest appearance on court was on October 15, where she locked horns with the defending champion, Suzan Lamens, in the Round of 16, and dominated the match, registering a 7-6(8), 3-6, 6-2 win. The match went to three sets, testing her physical and mental strength. During the deciding set, she faced an injury scare and took a medical timeout to treat her left leg.The Japanese returned to the court with a bandage on her thigh, but she eventually got an impressive win, securing a spot in the quarterfinal round. The day after this match, Osaka turned 28 on October 16, and on her special day, she found herself spending time at the hospital due to her leg injury. However, that did not dim her spirits, as she shared about it on her Instagram handle.Uploading a bunch of pictures from the hospital, including her selfie, a picture of her thigh, and a picture of her birthday cake, Osaka wrote:"Happy birthday 😂?" View this post on Instagram Instagram PostAlong with this, Osaka also made her feelings known about her situation by penning a humorous note on Threads that read:"Going to the hospital on your birthday is a whole new level of hilarious," wrote Naomi Osaka.The 28-year-old will be locking horns with Jaqueline Cristian in the Japan Open's quarterfinal round on October 17 at the Centre Court.Naomi Osaka expressed feelings about post-pregnancy struggles, opening up about her progressNaomi Osaka stepped into motherhood after giving birth to her daughter, Shai, on July 7, 2023, and after her pregnancy, she faced various struggles, including hair loss. In one of her latest TikTok videos, which was titled 'For My Hair Girlies Only,' she opened up about her hair loss struggles and how she has been solving the problem.“This is a very weird video. I've been really struggling with my hair for like the past two years. Like, during pregnancy and after pregnancy I lost my edges and stuff," said Naomi Osaka. She added:"They’re back now. Well, kind of. Kind of! Don’t look too closely. I also dyed my hair a lot, so I had to cut it off, blah, blah, blah. But I think it’s back now.”Along with this, Osaka also revealed that during her hair loss period, she used to tie her hair into a ponytail.“Anyway, I’ve been wearing a ponytail, as you can tell, because I didn’t know how to wear my hair. And then I watched one TikTok yesterday—don’t look too close, again—but I think we’re back! Hey!”Ahead of the Japan Open, Naomi Osaka competed at the Wuhan Open, where she couldn't progress further than the Round of 32 after being defeated by Linda Noskova.