The pair, who do not wish to be named, were travelling by taxi to Edinburgh at around 10.30 am last Friday, December 5, when their car was struck on the Abington slip road.
And when a driver, who witnessed the accident, stopped to assist, she was assaulted and the men who had collided with the taxi then stole her car and took off.
Meanwhile, the Lockerbie women were rushed to the nearest hospital, Wishaw General, after being cut out of the car.
One of them was placed in an induced coma and found to have injuries including broken ribs, a punctured lung and a shattered pelvis. She also had to have her spleen removed.
The other patient suffered various injuries. Both of them are still in hospital.
A spokeswoman for Police Scotland said: “At around 10.30 am on Friday January 5, po- lice were called to a report of a two vehicle road crash on the M74 at the Abington slip road.
“Emergency services attended and two women were taken to Wishaw General Hospital with serious injuries.
“A woman who stopped to assist was as- saulted and robbed of her car. The car was recovered a short time later.”
She added: “A 23-year-old man has been ar- rested and detained in police custody in connection with various offences including an alleged robbery.
“Extensive enquiries are ongoing to trace the other individuals involved.”
The 23-year-old appeared at Lanark Sheriff Court on Monday.