There are some exercises for your lower back and hip which can be done at a seated work-place. The things that should be kept in mind while doing lower back stretches are that the stretch should be strong and yet produce a comfortable sensation in the muscles being stretched and the stretches should be held for 15 to 30 seconds.

Out of the several lower back stretches, you can conveniently choose one that suits your personality and pain level. One of the easiest stretches you can do is: bring your knee up towards your chest, grab your thigh with your hands and keep your back straight as you do it. Don’t lean forward and do a strong but comfortable stretch. You should have a feeling of this stretch through the upper part of your buttock to the lower portion of your back. Then repeat the stretch on the other side of your body.

Another back stretche you can do at your work place is to hang on to the chair for stability and grab your ankle and bring it up towards your buttock so that you feel a stretch on the front of your thigh. In case of difficulty to grab ankle, pant legs can be grabbed and that will also provide the effect of stretch much the same right into the front of the thigh. This can be repeated with other leg.

One of the lower back stretches includes sitting forward in your chair keeping your back straight and have a small gap from the back of the chair. Keep face forward and your right leg crossed over your left leg. Your left hand should be the right knee. Gently pull towards your left side and slowly turn your head and shoulder to the right. You can keep turning this way until you see the wall behind your right shoulder. The turn should not be a forced one; it should give you a feel of nice stretch in your back. Hold on this position for 8 to 10 second; then relax and repeat on the other side.

These are some of the easy back stretches that can be performed conveniently just by sparing a few minutes out of your schedule.

Here is a great resource with explanations on which lower back stretches to do and how to do them:
Lower Back Stretches at PhysioAdvisor.com

The site is a physio site so they do have a good idea of what they are talking about. There are also photos of each stretch, which really helps you figure out what yuo are meant to do for those of you doing these at home.

Some of the stretches include:

• Lying Rotation – the one where you move your knees from side to side, nice and gentle for your back
• Prone on Elbows -  lie on your back and prop your self up on your elbows, this mildly stetches the spine
• Knees to chest – helps stretch and realign your back
• Standing Side Flexion – stand and move your hips side to side, great for loosening the lower back
• Lying Extension – same as the prone on elbows except prop yourself up to your hands
• Standing Extension – stand and arch your back backwards, natural move to stetch the back
• Standing Side Bend – like the standing side flexion but you use a wall to support you, allows you to stretch more without falling over
• Some leg stretches that also gently stretch your back

These stretches are ordered from easiest to hardest, so start off doing a lot of the easy ones every day and then move on.

The type of stretches include:

Upper Back Stretch – pushing against a wall

Lower Back Stretch – lying on the floor bring your knees to your chest

Hyperextension of Back – lie on your stomach and look up to the ceiling

Spine Rotation – lie on your back and move our knees from side to side

Cat stretch – get down on your hands and knees and arch your back

These are the perfect lower back stretches to help loosen muscles and get rid of your pain. Here it is:

http://www.abc-of-fitness.com/stretching-exercise/back-stretch.asp

Note: You can see an example of the type of diagrams at the top of this post.