Any good personal trainer (and probably the bad one's) will know that the center of the body is where it all starts; and is the main reason why core training has been at the fore front of all things training for the last 10 years.
As important as having a strong core is - it's role in being the magical cure for lower back pain has been somewhat overstated because it's only 1 part of the equation.
At FCF we pride ourselves on being able to determine causes of pain and dysfunction, not simply treat symptoms and pain spots.
Ask most people, personal trainer's and other treatment professional types and having a weak core is the biggest precursor for lower back pain.
The body works as a system with each joint being able to affect all the others in regards to joint integrity, alignment and level of function.

Below are 5 other reasons you have that nagging back pain:
1 - Your Hips are Out of Alignment
I love this picture! Everyone can see just what uneven hips can do to you from the head down to the foot. The main one specific to lower back pain is that your spine has to shift from it's anatomical position (i.e. a straight line).
This compromises stability because if it something is able to move freely then it isn't very stable.
Also have a look at what happens to the foot too which shows that shoe inserts are not much more then a band aid and probably just results in another shift of the pelvis to compensate again causing a other injury somewhere else
2 - You Move Too Much at the Lumbar Spine
As mentioned above the lumbar spine is a joint that is built for stability meaning that for it to carryout it's correct duties (force transfer, resisting movement etc) then stability of the lumbar spine is paramount.
When stability is poor then movement occurs in activities such as squatting, lifting your knee up to your hips and rotation and will result in your lower back and hips tucking under you as you squat deeper or lift your knee higher.
3 - Poor Thoracic Spine Mobility
Your thoracic spine which runs from your mid back to your upper back is built for rotation where each segment can elicit 7 - 9 degrees of rotation. With 12 segments you can potentially rotate 108 degrees just from the thoracic spine alone and without movement from anywhere else.
Compare this to the lumbar spine where each segment can elicit a poultry 1 - 2 degrees of rotation per segment. With 5 segments you can only manage 10 degrees rotation at the lumbar spine.
This being said you actually need thoracic extension (lifting your arms above your head) before rotation so if you can't get your arms to 180 degrees without leaning back through your lower back, then work on this and then rotation later.
There is not many people alive who have ankles that are as mobile as they need to be. The implications of poor ankle mobility, especially in dorsi flexion (pushing your knee over your toes while keeping your heel on the ground), is poor knee and hip tracking, the development of mobility at the lumbar spine and even opposite side shoulder pain can become a problem.
The biggie when it comes to training is squatting. When you can't move your knees over your toes but you still want to keep your heels flat on the ground then to get more depth something else has to move. Yep you guessed it, the lower back and hips. If the brain doesn't let them move for a fear of injury (yes the brain can stop you doing stuff it perceives as a danger - future post idea!!) then your weight will shift forwards.
Now regardless of where you have placed the load (on shoulders, in front of chest, down by sides), it has now been pushed forwards which puts more stress on your lower back because the load has been moved away further from the anchor (like hanging off the end of your clothesline when you were a kid and watching it bend).
5 - Your Sleeping Position/s
Let's keep this simple.
If you're a back sleeper then your lower back is probably being forced into extension (arching) so use a small lap cushion/pillow and place it under your hamstrings to flatten your lower back out a little.
If you're a side sleeper then to limit rotation of the lower back from your top knee resting your lower knee or the bed then use the cushion/pillow to place between the knees and/or between the bed and your top knee if the bottom leg is in a extended straight leg position.
This won't take your back pain away completely but it can alleviate stiffness upon waking and I do this each and every night. I even take my cushion with me when I go away!!
So there are 5 lower back savers, or helpers, that you can use today to alleviate some of that back pain.