Survivors of the Westminster terror attack last March claim they have been “airbrushed” from the inquest into its five victims, which opened last week.

Travis Frain, 20, said that hardly any of the attack’s 50 survivors had been invited to offer evidence at the inquest at the Old Bailey, leaving many to claim that vital testimony will be omitted.

Khalid Masood, 52, ran down and killed four people after ploughing a car into pedestrians on Westminster Bridge on 22 March last year, then stabbed an unarmed police officer to death.

Frain, who suffered multiple injuries, including a broken leg, after being struck by Masood’s vehicle, said: “It seems that if you were injured, your testimony is somehow worth less. It seems bizarre, it’s like airbrushing our accounts from the one opportunity for them to be made public.”

His disquiet has fed into broader concerns from the dozens of injured survivors that they have been ignored by politicians but also treated differently to those caught up in other 2017 terror attacks, such as London Bridge and the suicide bombing at an Ariana Grande concert at Manchester Arena.

Frain, who was visited by Prince Charles when in hospital, said that the approach to the survivors by Andy Burnham, the mayor of Greater Manchester, was starkly different to the one shown by his London counterpart, Sadiq Khan.

“We have yet to have a single politician of any party meet with us,” Frain said. “It seems really weird: there’s been no letter, no correspondence at all from the London mayor. My big gripe is when you compare it to other terrorist attacks. I’ve spoken to quite a few survivors of the Manchester attack and they’ve jokingly said they’ve got Burnham’s mobile number on speed dial.”

Frain, a trustee of the Tim Parry Johnathan Ball Peace Foundation, which supports survivors of terrorism, added: “The attack was such a big event but it hasn’t been treated that way by the people who quite often like to make a big thing of talking about such events.”

According to Frain, only survivors who are bereaved have been invited to give evidence at the inquest, and even some of them have voiced concerns over the process.

Andrei Burnaz, whose girlfriend Andreea Cristea, 31, died after being struck by Masood’s car and thrown into the Thames, and who delivered his witness account to the inquest on Thursday, told the Observer that despite travellingfrom Romania to give evidence, he did not think he had been useful to the proceedings or that the process had been cathartic.

“I am just not sure how helpful I was to the inquest, or how helpful the inquest was to me,” Burnaz said. He also revealed he had paid for his flight from Bucharest, his London hotel and living costs out of his own pocket, having initially not been told that he could claim the expenses back.

Frain, from Darwen, Lancashire, said that there was confusion among other survivors over the cost of attending the inquest, which is scheduled to run until next month.

“I know of others who were injured who just can’t afford to travel down the country for the inquest, but they really want to find out what happened that day and see the CCTV for themselves, or meet other victims because they haven’t had the chance to do that.”

Survivors are also concerned about the failure to have an official commemoration for all those caught up in the Westminster attack.

“Apparently, they consulted the bereaved but didn’t consult those who survived. We’d have liked to have been asked about this. On the anniversary I went to the bridge and there was an impromptu gathering of people affected by the attack – about 20 of us – who just formed a gathering. We didn’t know each other before that.

“But there were people walking by, cars passing, the bridge wasn’t closed, it was like a regular day. The irony, the real kick in the gut, was that there was a service happening nearby in parliament that was only for MPs and lords to attend.”

Frain, though, did say that that his rehabilitation costs had been paid for following a decision in March by the Motor Insurance Bureau (MIB), an insurance industry fund to help the victims of untraced or uninsured vehicles or drivers, became liable for claims where death, injury or damage is caused by an uninsured vehicle in an act of terrorism.

Keith Barrett, partner at London lawfirm Fieldfisher, who is representing a number of Westminster attack survivors, said: “What people physically and mentally scarred by terrorist attack need immediately is fast and easy access to ongoing rehabilitation to help them try to rebuild their lives.”

“The current government CICA fund for victims of violence - who are at their most desperate and vulnerable - is simply too complicated, unreliable and inadequate to offer even the most basic care and compensation.

“The government has just announced it will finally overhaul CICA, which is long overdue. Terrorism sustains via the horror and pain inflicted on the injured, which continues indefinitely, and victims must be properly cared for.”

Siân Jones of Bircham Dyson Bell, one of the solicitors to the inquest, said: “We have selected for these inquests the witnesses who can best give evidence as to the last movements of the deceased or their immediate aftercare.”

• This article was updated on 16 September 2018 to include comments from Keith Barrett, partner at London lawfirm Fieldfisher.