At Bristol Crown Court on Friday, James and Adams were found guilty of conspiracy to cause intentional grievous bodily harm (GBH) for the attack on Tjitendero.
James was also found guilty of intentional GBH following the assault on Ford that took place 10 days earlier.
In the second attack, Tjitendero was walking to Southmead Hospital in Bristol when he was hit by a blue Honda Accord.
James and Adams fled the scene, with one shouting racial abuse at Tjitendero who was pinned against a wall by the car.
Detective Superintendent Mike Buck, of Avon and Somerset, branded the attacks “absolutely sickening”.
“It was only later in the investigation that we identified the attack on Julian Ford, 10 days beforehand, and realised the significance.
“This wasn’t an isolated incident. These were two linked attacks.
“Patrick James was filming the attack and you hear him on the video, and the driver, laughing both before and afterwards as they drive off. Absolutely sickening,” Buck said.
CCTV footage showed Tjitendero heading towards a bus stop about 4.30pm on July 22, 2020, after finishing a shift at Southmead Hospital.
Buck said the blue Honda car appeared “from nowhere” and hit Tjitendero from the back.
“A car attacked him from behind. He had no chance and was left with devastating injuries.”
The court heard that on July 16, James had paid £300 (about $630) for the blue Honda Accord involved in the collision.
CCTV from petrol stations in the area showed James using the car over the following days.
Adams’ DNA was found inside the car, which he had told officers he had been in at times.
James, of Bristol, was convicted of intentionally causing GBH to Ford.
Adams, also of Bristol, failed to appear in court and in his absence was tried and found guilty on the separate charges relating to Tjitendero. A warrant was issued for his arrest.
Two other men, Jordan McCarthy, 22, and Daniel Whereatt, 51, denied a charge of conspiracy to cause GBH to Tjitendero and were acquitted by the jury.