Industry insiders said legal advice sessions - considered by some patients to be intrusive - have been offered at larger NHS trusts for years.
The Department of Health told BBC Radio 4's You and Yours it was "looking at all options" to stamp out the practice.
NHS England said lawyers should be kept out of hospital "wherever possible".
Salford Royal NHS Trust has hosted legal advice surgeries by lawyers in its spinal and head injury trauma centres since 2012 but says it makes no money from the arrangement.
The trust said lawyers provide services free of charge and advise patients on matters such as employment rights as well as negligence claims.
Personal injury claims solicitors from Potter Rees Dolan hold twice-weekly advice clinics on trauma wards at Salford Royal.
Hugh Potter, partner at the firm, said: "This service was created to fill the gap left by the reduced state funding for Law Centres and the Citizen Advice Bureau.
"The firm does this work out of a sense of public duty and for the benefit of those who are at their most vulnerable."
He added that if a patient has a claim for compensation they are given a choice of legal firms approved by the hospital trust.
NHS hospitals do not typically advertise Legal Advice Surgeries on websites, but Salford Royal said trauma patients are made aware of the service via leaflets placed on wards.
Mr Potter said staff on wards may also play a role.
He said: "The nurses will do their best to make sure the patient is aware of the service, that's all they do.
"They will say, usually, 'are you aware of the legal service?'"
In the past year, the total payout for clinical claims against the NHS has risen to £1.48bn.
Legal firms' costs have risen to an average 55% of the total claim value, where damages are below £100,000.
Mr Potter said it would be "extremely rare" for a Salford Royal patient advised by its solicitors to sue the hospital.
However, the hospital said it did not have a contract in place with the firm to prevent to such a claim.
Conservative MP Andrew Bridgen, who has campaigned against personal injury claims advertising in NHS Hospitals, said he was shocked by the findings.
He said: "Local NHS Trusts are feeding a monster that's eating the NHS."
"I've spoken to the [health] minister, Philip Dunne, and it's clear he has no knowledge that this is actually going on."
"That seems to suggest hospitals are carrying this out below the radar, as far as the Department of Health is concerned."
A Department of Heath spokesperson told the BBC: "It is completely unacceptable that personal injury lawyers are using the NHS in this way, which is why we are looking at all options to stamp out this practice."
An NHS England spokesperson said: "Wherever possible, let's keep lawyers out of hospital, and doctors out of court."
NHS spokespeople in Scotland and Northern Ireland said it was a matter for individual trusts, while NHS Wales said it discourages the practice.
However, the Association of Personal Injury Lawyers defended hospital advice services.
President Neil Sugarman said: "This is really a case of signposting the options to injured people.
"It is in their interests to know how to access an accredited solicitor who specialises in brain and spinal injuries.
"Of course, solicitors are not permitted to make approaches and APIL condemns any inappropriate practices."
Deputy chief executive at Salford Royal, Elaine Inglesby-Burke, told the BBC: "This is a free service provided in the best interests of patients."