The five-times European Tour winner was three-over-par for his round and six-over for the tournament when he pulled out.
Hoey, who romped to a four-stroke victory at the Russian Open 12 months ago, told reporters that he was unsure if he would be fit to defend his title at the Tseleevo Golf Club in Moscow next week.
The 35-year-old has had a solid season on the European Tour, achieving five top-10 finishes.
Hoey picked up his biggest payday of the campaign, $189,000, after tying for second place at the Tshwane Open in South Africa in March.
(Writing by Tony Jimenez; Editing by John O'Brien)