The surgery began at 8:30 a.m. at Seoul St. Mary's Hospital in southern Seoul and lasted about two hours, they said.
"The surgery was successfully carried out, and Park is now recovering," the hospital said, adding orthopedic surgeon Kim Yang-soo performed the operation.
The 67-year-old Park, who has been in the Seoul Detention Center since March 2017 over a massive corruption case, was admitted to the general hospital Monday. Park was previously allowed to occasionally visit the hospital for treatment for a lumbar disc condition and other ailments or to have an oriental medicine doctor examine her in prison during her detention over the past two years and five months.
She was reportedly unable to use her left arm due to a rotator cuff tear.
Park will stay at a VIP room on the 21st floor of the hospital in the Banpo district and her contact with the outside will be restricted, the hospital and the ministry said.
The hospital expects Park's recovery and rehabilitation to take about two to three months.
"Park's rotator cuff tear advanced to frozen shoulder. During surgery, a partial rupture of her biceps muscle and arthritis, which were not seen on an MRI, were observed," said Kim in a media briefing.
A rotator cuff tear is a condition in which the four muscles covering the shoulder joint are weakened or torn. These muscles play a role in maintaining the rotational motion and stability of the shoulder joint.
Kim explained one of the four muscles covering Park's shoulder joint was torn, and the surgery was performed with arthroscopy, a minimally invasive procedure, without skin incisions.
In addition, Park was treated for frozen shoulder in her left arm, which causes symptoms, like stiffness, reduced mobility and pain in the shoulder joint.
Due to a combination of a rotator cuff tear, a frozen shoulder, a partial rupture of biceps muscle and arthritis, she might not have been able to lead a normal life, the doctor speculated.
"She might have had difficulty in sleeping at night due to extreme pain caused by the frozen shoulder, and the restricted shoulder movements in all directions may have interfered with her daily routine of eating, changing clothes and going to the bathroom, for instance," Kim said, stressing sufficient and careful rehabilitation will also be important for her.
The doctor said he will also have to pay constant attention to Park's right shoulder, which is not as bad as her left shoulder.
Park is serving a total of 32 years in prison for bribery, abuse of power, election law violations and other charges.
The Ministry of Justice permitted Park's hospitalization two days after the prosecution last Monday rejected her request for a stay of execution of her sentence made on grounds of worsening illnesses. Her first such request in April was also rejected.
On Aug. 29, the Supreme Court ordered a retrial of the corruption case in which she was sentenced to 25 years in prison by an appeals court. The top court said some of the bribery charges should be dealt with separately, which may lead to heavier punishment. (Yonhap)