In a Twitter thread by user @mustangsart, the fan points out that in both the show and the video game series, Geralt’s disability is completely erased from the narrative. In the original novels, written by Andrzej Sapkowski, Geralt is injured toward the end of Time of Contempt, “shattering” his elbow and thigh. According to the fan, the injury leaves our fearless monster hunter “screaming in agony and delirious until the Dryads help him.”
Of course, Geralt is healed, but in the novels, he never fully recovers from this injury. Instead, Geralt is riddled with chronic pain throughout the rest of the series.
“It affects his gait, causing him to walk with a limp that increases in severity depending on the weather. He finds that riding Roach for long periods is very uncomfortable. He is restless sitting down because suddenly his knee will seize and [he] needs to stand up again to stretch it out,” @mustangsart explains.
Source : https://www.distractify.com/p/what-is-geralts-disability-the-witcher