YSR Congress party leader Sharmila will undergo knee surgery at a private hospital Tuesday, party sources said.
The sister of jailed MP and party chief Y.S. Jaganmohan Reddy was injured during her 'padyatra' in Ranga Reddy district two days ago.
The injury forced her to break the walkathon and after series of tests, doctors found she suffered two types of injuries which required a surgery.
Party sources said Sharmila would undergo the operation at Apollo Hospital.
Doctors said she would have to take rest for at least three weeks.
Sharmila launched the 'padyatra' Oct 18 from the grave of her late father Y.S. Rajasekhara Reddy in Kadapa district and has so far covered four districts.
Her injury has come as a setback to the party as she had embarked on the 3,000-km 'padyatra' to boost th morale of the party in the absence of her brother, who was arrested by the Central Bureau of Investigation (CBI) in illegal assets case in May this year.
Sharmila was drawing good crowds during her walkathon, aimed at targeting both the ruling Congress and the main opposition Telugu Desam Party (TDP).
Though not holding any position in the party, she decided to undertake the 'padyatra' as her mother and party's honorary president Y.S. Vijayamma was unable to walk long distance due to arthritis.
Emulating her late father, Sharmila launched the 'padyatra' a few days after TDP chief N. Chandrababu Naidu embarked on 2,320 km-long walkathon to interact with people and to strengthen the party ahead of the 2014 general election.
Rajasekhara Reddy had walked 1,500 km across the state in 2003 and the walkathon helped the Congress to come to power in 2004.