The Spaniard suffered a frightening high-side going through Farm Curve during FP4 for last weekend's British Grand Prix and had to be stretchered off track.
Espargaro was taken to the circuit's medical centre and had to be helped into the building by two members from his Aprilia team, but was later cleared to take part in qualifying shortly after.
The Aprilia rider heroically qualified sixth and was passed fit to race on Sunday morning, though struggled with traction meant he could no more than ninth in the 20-lap grand prix.
Espargaro confirmed on Sunday that he would go to Barcelona today for checks at the Dexeus hospital, which have revealed he has suffered a fracture in his right heel.
He does not require surgery but has been ordered to rest for the next week in order to be fit enough for next weekend's Austrian Grand Prix.
A brief statement from Aprilia read: "Following medical checks carried out today at the Dexeus Hospital in Barcelona, Aleix Espargaro has been diagnosed with a heel fracture in his right foot.
"The Spanish rider, the victim of a frightening high-side during the last free practice session at Silverstone, then stoically took to the track for both qualifying and Sunday's race.
"The injury does not require surgical treatment, and Aleix has been prescribed seven days of absolute rest during which he will have to use crutches in order not to strain his injured foot.
"The aim is to arrive at the next race weekend (19-21 August, Austria) in the best physical condition."
Despite his injury woes, Espargaro only lost one point to championship leader Fabio Quartararo in last Sunday's race at Silverstone.
Quartararo, who had to serve a long lap penalty for a collision at Assen with Espargaro, came under attack from Espargaro on the final lap of the British GP, and only just held on to finish eighth.
As a result, Quartararo's championship lead stands at just 22 as the series heads to the Red Bull Ring on 19-21 August.
