Pulsating feeling in leg

Over the past two weeks or so I've noticed a strange pulsating feeling in my right thigh (right of center about 6 inches above knee).  It isn't painful, but it is strange in that there is no regular rhythm to it.  It comes and goes throughout the day, sometimes it's pretty active other times not.  I would describe it almost like a jello type substance is being squeezed through my thigh.  Also, I don't think it's a muscle twitch, since it feels very deep and I don't see my leg moving.  

I was worried about a blood clot.  I'm 30 in good health, exercise most days.  However, I also sit at the computer for really long stretches during the day, also I recently completed a very long (21 hr) road trip.  

[Lee Kirksey, MD]

I would make an appointment to see your doctor and have an ultrasound which can determine if it is a fluid collection of fat (lipoma). If it is actually pulsating, you should consider doing that as soon as possible. Its quite unusual to have the acute onset of a pulsatile mass absent trauma to a blood vessel. Blood clots generally occur in veins, which are not pulsatile, however your doctor can also see a blood clot with ultrasound