The 21-year-old Indian has not competed since picking up the injury to his right elbow late last year and was working extensively on his core strengthening and flexibility with an eye on the World Championships.
The former world junior champion underwent an arthroscopy procedure to remove bone fragments which were causing him discomfort on Thursday and was released from the Mumbai hospital on Friday.
"Undergone elbow surgery in Mumbai by Dr. Dinshaw Pardiwala," Chopra said in a social media post, accompanied by a picture of him lying on a hospital bed with his right arm in an elbow brace.
"Will require some months of rehabilitation before I can start back with throwing. Hoping to return stronger.
"Every setback is a setup for a comeback. God wants to bring you out better than you were before."
Last year, Chopra became only the third man to win an athletics gold for India at the Commonwealth Games after sprinter Milkha Singh in 1958 and discus thrower Vikas Gowda in 2014.
A throw of 86.47 metres was enough to take the title on the Gold Coast and he followed that up with 87.43 metres at the Diamond League leg in Doha in May.
At the Asiad in Jakarta he threw even further, clearing a season's best distance of 88.06 metres for the title -- placing him sixth on the IAAF top list for 2018.
Hailing from the Northern Indian state of Haryana, which is better known for producing wrestlers and kabaddi players, Chopra is currently ranked fifth in the IAAF world rankings in javelin.
He was targeting a throw of 92 metres and finish in the top six at the World Championships in Doha.
"Neeraj went through consultations with doctors in India and his scans were sent to multiple international experts as well, who all suggested that the elbow arthroscopy would be the best alternative," said Manisha Malhotra, Head of Sports Excellence at JSW Sports, the organisation which manages the athlete.
"After considering all options and feedback, Neeraj decided to stay in India and undergo the procedure."
(Reporting by Sudipto Ganguly; editing by Nick Mulvenney)
