Low Back Injuries After a Collision

Standing, your lumbar discs carry your upper body weight in a position they evolved to handle. Sitting raises the pressure inside those discs substantially, and sitting slightly leaned forward raises it further. Now add a collision. You are in the highest-load posture available to the human spine at the exact moment a large force arrives.

The lap belt pivot

In a frontal impact the lap belt holds your pelvis firmly in the seat while your upper body continues forward. The spine has to bend somewhere, and it bends across the belt line. The lumbar segments become a hinge, folding forward under load in a way that drives pressure toward the back of the discs, which is precisely where the material is thinnest and where nerve roots are waiting.

In a rear impact the sequence reverses. The seat back drives your pelvis and low back forward while your torso ramps up the seat, compressing and shearing the same segments in the opposite direction.

Three structures, three patterns

Disc injury tends to produce pain that is worse with sitting, worse with bending forward, worse first thing in the morning, and worse with coughing or sneezing. If disc material contacts a nerve root, pain travels into the buttock and down the leg in a defined band.

Facet injury behaves almost the opposite way. It hurts more with standing, arching backward, and standing still for long periods, and often eases when the patient sits or leans on a shopping cart. Pain stays closer to the spine and may refer into the buttock but rarely below the knee.

Sacroiliac injury produces pain on one side, low and off to the side of the spine, that is aggravated by rolling over in bed, getting out of a car, or climbing stairs. The lap belt loads the pelvis asymmetrically, so one-sided SI pain after a crash is common and frequently mistaken for hip pain.

The Las Vegas problem

This is a driving city. Most people here go straight back to a commute, and the commute is the aggravating posture. Patients regularly tell us the back was manageable until they drove to work, and then it was not. Recovery has to account for the fact that you cannot simply stop sitting.

How we approach it

The first job is figuring out which of the three is driving the pain, because the treatment diverges sharply. A disc that responds well to extension work will get worse with the flexion exercises that help a facet problem. We test rather than guess.

For disc-related pain with leg symptoms, non-surgical spinal decompression is often part of the plan. It applies controlled traction to the injured segment in a way that unloads the disc rather than compressing it further, which is the opposite of what your car seat does to it every day.

If your back has not been right since your accident, call (725) 255-7333. Henderson, southwest Las Vegas, and North Las Vegas.