Tingling on upper thigh-what could this mean?

There are many possible causes of tingling:

Remaining in the same seated or standing position for a long time

Injury to a nerve -- for example, a neck injury may cause you to feel numbness anywhere along your arm or hand, while a low back injury can cause numbness or tingling down the back of your leg

Pressure on the spinal nerves, such as from a herniated disk

Pressure on peripheral nerves from enlarged blood vessels, tumors, scar tissue, or infection

Shingles or herpes zoster infection

Lack of blood supply to an area -- for example, cholesterol (plaque) build up from atherosclerosis in the legs can cause pain, numbness, and tingling while walking (this is called vascular claudication); frostbite can also reduce blood supply and lead to numbness

Other medical conditions, including:

Carpal tunnel syndrome (pressure on a nerve at the wrist)

Diabetes

Migraines

Multiple sclerosis

Seizures

Stroke

Transient ischemic attack (TIA), sometimes called a "mini-stroke"

Underactive thyroid

Raynaud's phenomenon

Abnormal levels of calcium, potassium, or sodium in your body

A lack of vitamin B12 or other vitamin

Use of certain medications

Toxic nerve damage due to lead, alcohol, or tobacco

Radiation therapy

http://www.nlm.nih.gov/medlineplus/ency/article/00...

due to the leaning affect you are experiencing this could be putting pressure on your sciatic nerve try a different job on saturdays if possible