The 25-year-old had to be carried off after 34 minutes of Newcastle Falcons' match at Harlequins on Sunday.
It was feared he would face another lengthy lay-off, having been plagued by injury since kicking England to victory in the 2003 World Cup.
As well as missing the Six Nations finale against Scotland at the weekend, there was genuine concern he would also be forced out of the Lions' tour of New Zealand this summer.
Without putting a timescale on Wilkinson's likely recovery, Newcastle director of rugby Rob Andrew has delivered a prognosis which will offer cheer to all concerned with England and the Lions.
The injury does concern the medial ligament of Wilkinson's left knee, which has caused him trouble already this year, but Andrew feels positive.
"An injury is never good news, but this could have been so much worse, so there is some sense of relief,"' said Andrew.
"Jonny has shown in recent years that he has the strength of character to get over a blow such as this, and I am sure he will return stronger than ever, such is his amazing determination.
"We won't be making any comments at this stage as to when Jonny might return, but we are just thankful that there is no damage to his anterior cruciate ligament, which would have meant a much longer period out of the game."