Low back pain is one of the most common physical complaints. When people experience this discomfort, they often suspect an imbalance in the body’s foundation is to blame. The pelvis connects the torso and lower limbs, acting as the structural center of the body. Its alignment directly impacts the stability of the spine above it.
The Direct Answer: Understanding Hip Misalignment
Yes, uneven hips can cause back pain because the pelvis acts as the foundation for the spine, and any tilt or rotation transmits stress upward. This uneven positioning is clinically referred to as a lateral pelvic tilt or a pelvic obliquity, where one side of the pelvis is elevated. This misalignment forces the body to compensate to keep the head level.
The term “uneven hips” refers to a difference in the height of the pelvis’s bony landmarks, often resulting in a leg length discrepancy (LLD). A minor LLD (less than five millimeters) is common and often asymptomatic. However, a larger discrepancy can significantly alter the load distribution on the spine.
Structural vs. Functional Causes of Uneven Hips
Uneven hips and leg length discrepancy (LLD) fall into two main categories: structural and functional. A structural LLD is an anatomical difference in the actual length of the lower limb bones, such as the femur or tibia. This difference is fixed, often due to congenital factors, trauma, or previous surgeries. Structural discrepancies greater than 5 millimeters are considered clinically significant, as they create a permanent pelvic tilt.
A functional LLD occurs when the legs are physically the same length, but one appears shorter due to muscular or soft tissue imbalances. This misalignment is dynamic, often caused by a rotational issue in the pelvis or sacroiliac joint dysfunction. Common contributors include tight hip flexor muscles, weak gluteal muscles, or chronic poor posture.
The Biomechanical Link to Back Pain
When the pelvis is tilted laterally, the kinetic chain is disrupted, causing compensatory movements throughout the body. The primary reaction is spinal compensation, where the spine develops a slight lateral curve, known as functional scoliosis, to re-center the head and maintain upright posture. This bending places asymmetrical strain on the vertebral segments.
Muscles along the spine, particularly the quadratus lumborum (QL) and paraspinal muscles on the elevated side, must constantly contract to hold this compensatory curve. This chronic overuse leads to muscle strain and tightness, a common source of localized back pain. Over time, uneven weight distribution increases asymmetrical loading on the lumbar discs and facet joints, accelerating joint wear and potentially leading to degenerative changes like disc compression or facet joint arthritis.
Diagnostic Steps and Treatment Approaches
Diagnosis begins with a thorough physical examination and gait analysis to assess posture. Practitioners typically measure leg length using a tape measure to determine a preliminary LLD. Imaging studies are often necessary to differentiate between structural and functional causes.
A standing X-ray of the pelvis and hips is the most accurate method to measure the true anatomical LLD. Clinicians use blocks underneath the shorter limb to level the pelvis and determine the size of the structural discrepancy. Treatment is tailored based on the cause. Functional unevenness is managed with physical therapy, focusing on stretching tight muscles and strengthening weak ones (like the glutes and core) to restore pelvic balance. Structural discrepancies greater than 5 millimeters are often addressed with conservative methods such as shoe lifts or orthotics. Surgery is reserved for severe, rare discrepancies exceeding 20 millimeters.