“Lumbo” refers to the lumbar spine which is located on the lower part of the spine. L1-L5 are the five vertebrae located below the thoracic region of the spine and above the sacral region. Our Spinal Column also called our vertebral column, is made up of 24 bones that hold the body in an upright position. The 24 bones, called vertebrae, make up the vertebral column which consists of 5 regions. The 5 regions are (from top to bottom) the cervical spine, thoracic spine, lumbar spine, sacrum, and coccyx. The lumbar spine facilitates various movements in different planes: front and back (flexion and extension), side to side (side bending), and twisting (rotation). The lumbar spine (L1-L5) is located above the sacrum which is located between the right and left pelvic bones. When there is a change in the posture of the pelvis, there is also a change in the posture of the sacrum and lumbar spine.
Extensor, Flexor, and Oblique Muscles
There are three types of muscles that work together to create movement of the spine, the extensor muscles, flexor muscles, and oblique muscles. The extensor muscles hold the body in an upright position and assist in lifting objects, for example, boxes from the ground, and are in the back of the spine. The flexor muscles are in the front of the spine and assist in forward bending, lifting, and arching. The oblique muscles are the side muscles attached to the spine and help with rotation of the spine and help to maintain posture.
What is Lumbopelvic Rhythm?
It is the coordinated movement between the lumbar spine and pelvis when performing forward and backward movements. Flexion and extension occur on the sagittal or longitudinal plane, which divides the human body into right and left. Flexion refers to reducing the angle of two bones attached together. For example, spinal flexion is when one bends forward to touch their toes. Extension is increasing the angle of two bones attached together. For example, when one bends backward.
Bending forward is described as trunk flexion and hip flexion (flexion means a reduction in angles) combined with tilting of the pelvis anteriorly. The Iliocostalis Lumborum, Longissimus Thoracis, and Spinalis Thoracis are three groups of muscles collectively called the erector spinae. The three groups of muscles, Erector Spinae (lumbar extensors) originate from the sacrum and extend vertically on both sides of the spine. As the lumbar region of the spine flexes and the pelvis tilts anteriorly on the femur, the erector spinae lengths to maintain posture during movement, for example, walking (causing tension in the hamstrings). When the human body returns to an upright position, the lumbopelvic rhythm reverses. First, the pelvis tilts posteriorly on the femur as the erector spinae contracts concentrically (shortens). The hip extensor muscles will reduce loading on the lumbar spine from forceful contractions of the spinal flexors.
The hip extensor muscles include the hamstring muscles and gluteus maximus. When the hip extensor muscles experience tension, it results in eccentric activation. For example, during a normal gait cycle, when the hamstring muscles experience tension they lengthen to support the weight of the body against gravity and to absorb shock.
Importance of maintaining Lumbo-Pelvic Rhythm:
The lumbopelvic rhythm is the coordinating relationship between the lumbar spine and pelvis. The natural, healthy posture of one’s pelvis equates to a natural, healthy posture of the lumbar spine. When the pelvic posture is compromised it creates postural distortion in the lumbar spine and above (thoracic and cervical spine). The sagittal, frontal, and transverse planes are examined to locate postural distortions.
Dissociation between the Lumbar Spine and the Pelvis with coordinated movements to prevent back, hip, and lower extremity pain and dysfunction:
What happens when there is dysfunction in the lumbopelvic rhythm? The lumbopelvic rhythm is the ability to dissociate or perform independent movements of the pelvis and the lumbar region of the spine. When one suffers from lumbopelvic rhythm dysfunction or inability to dissociate movements of the lumbar spine and pelvis, it results in one of two things:
When your pelvis tilts anteriorly, this causes increased pressure on facet joints.
When your pelvis tilts posteriorly, it causes the lumbar spine to bend or flex forward placing an increase of pressure on vertebral discs.
This can result in back pain or injury that can be minimized or eliminated by learning how to dissociate and coordinate movements between your lumbar spine and pelvis.
Lumbopelvic dysfunction can occur due to the following:
Weakness or tightness in the muscles that surround the pelvis and/or are within the pelvic girdle
Malalignment
Damage to ligaments
Hyper or hypomobility
Pain or muscle spasms due to an increase in stress or strain on lumbopelvic joints
Low back pain or stiffness in the lumbar spine region can be due to decreased coordination between your lumbar spine and pelvis also known as Lumbopelvic rhythm dysfunction. To address this issue, your Physical Therapist can help you be mindful of your body awareness, promote neuromuscular re-education, and help you to learn the basics of healthy movement patterns.