The flanker was injured late on in his country's 20-11 victory over South Africa in Cardiff on Sunday (AEDT) when Wales made it nine successive Test victories for the first time this century.
Jenkins was voted man-of-the-match but left the field after full-time on a stretcher, with coach Warren Gatland fearing he had damaged his anterior cruciate ligament.
The 25-year-old had a scan on Monday and will learn his recovery timetable after meeting a specialist next week, but returning in time for the start of the Rugby World Cup next September is his objective.
"I've been for a scan so [I'm] just waiting to see a specialist next week then go from there," he said.
"We all know what's happening at the end of this season and that's still my goal at the moment until someone tells me otherwise.
"I want to be back as quick as possible, playing as soon as possible and back playing well. That's my goal at the moment.
"I've been trying to keep my knee moving and get the swelling down.
"If I need surgery I need to keep the swelling to a minimum otherwise it just delays the process."
Bath has revealed Taulupe Faletau, another Wales back-rower, is expected to return from his broken arm in mid-December having missed the recent internationals.