A 75-year-old man whose loss of concentration behind the wheel caused a pedestrian serious injury has been allowed to keep his driving licence.

Peter Whipps, of Suncrest Rise, Stowmarket, admitted careless driving at Suffiolk Magistrates' Court on Tuesday after his BMW 325 mounted a footpath beside the A1120 and collided with a man in his 50s.

Prosecutor Colette Harper said the pedestrian was walking with two work colleagues alongside the 40mph northbound carriageway of the road in Stowmarket when the crash happened at about 12.15pm on March 19.

"The nearside wing of the vehicle collided with his left side," she told magistrates.

"Mr Whipps stopped the vehicle and waited for the arrival of police.

"The pedestrian felt like he had been thrown into the air.

"He suffered multiple injuries, including a deep cut to the right side of his head, a large graze to the right shoulder and a fractured left wrist."

The pedestrian's other injuries included a broken finger, swollen spleen and bladder, lacerated lower bowels and extensive bruising to the stomach.

Three days in the high dependency unit of Addenbrooke's Hospital included a four-hour operation to remove car debris from his leg, including shards of plastic a centimetre from the femoral artery.

He remains unable to work, drive or resume any regular daily activities, the court heard.

Helen Korfanty, mitigating, said Whipps had been equally saddened and traumatised by the injuries he caused in the collision.

"It appears to be some momentary distraction," she added.

"His recollection is that he instinctively swerved to avoid another vehicle passing very closely.

"He has held a licence for almost 60 years with no history of accidents."

The court heard Whipps had since completed a one-hour driving assessment and been found competent enough to continue making journeys by car, including to dialysis appointments in Ipswich three times a week.

Magistrates endorsed his licence with nine points and fined him £403 for driving without due care and attention.

He must also contribute £85 to the cost of prosecution.