Zia, 73, was last week admitted to a specialised state-run hospital here for proper treatment following a court order as her health deteriorated.
Zia was jailed for five years in February after being convicted of corruption involving an orphanage.
"She has been suffering from rheumatoid arthritis for the past 30 years, which has played a role in the paralytic deformity of her left arm. These kinds of problems are rising as her gout is worsening," Dr Abdul Jalil Chowdhury told a press briefing at Bangabandhu Sheikh Mujib Medical University (BSMMU) Hospital on Monday.
The head of the five-member medical board tasked with treating the incarcerated BNP chairperson has said that Zia's left arm has ended up paralysed and bent as she did not take her arthritis medicines properly, Dhaka Tribune quoted the doctor as saying.
"She is also having trouble with one of her knees that had been replaced. So that's another issue," he added.
He said that Zia had been suffering from diabetes for the past 20 years, but she did not take the prescribed insulin. "So we will have to find out the level of her diabetes first."
The BNP chief was admitted to the BSMMU Hospital on Saturday for better treatment following a High Court order.
She has been suffering from a number of ailments for a long time, according to doctors who earlier treated her.
Earlier, the BNP chief's personal doctors who had met her in the old Dhaka central jail said that she suffered a "mild stroke" on June 5.
On September 16, another government-formed medical board had suggested admitting Zia to a hospital like the BSMMU, although they said they did not find symptoms of any serious disease in her during medical tests.
Zia was granted bail in a corruption case in May but remains in jail while she fights dozens of other violence and graft charges.
Zia was found guilty then of embezzling money intended for an orphanage, a charge she dismissed as politically motivated.
She is appealing against the verdict which bars her from standing in a general election to be held in December.
The BNP alleges that the trial was politically motivated to debar her from contesting elections, but the government denies the allegation.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)