你的下背部為甚麼會疼痛？

Dr. Nichol Tang, D.C. 

"Low back pain is one of the most prevalent musculoskeletal disorders, affecting approximately 80% of adults at some point in their lives" (Hoy, Bain, Williams, March, Brooks, Blyth, Woolf, Vos & Buchbinder, 2012). "Chronic low back pain also represents the leading cause of disability worldwide and is a major welfare and economic problem" (Allegri, M., Montella, S. & Salici, F., 2016).

It commonly stems from mechanical stress, poor posture, degenerative changes, or underlying spinal conditions. This blog explores the main causes of lower back pain, its associated symptoms, and effective self-care strategies to improve spinal health.

Causes of Low Back Pain: Mechanical, Postural, and Degenerative Factors

Mechanical Causes

• Strain or sprain injury:

Strain or sprain injury is one of the most common causes of acute lower back pain, typically resulting from sudden overload, lifting, repetitive stress, or trauma (Deyo & Weinstein, 2021). When muscles are overstretched or forcibly contracted beyond their capacity, microtrauma occurs in the muscle fibers or tendons, leading to localized inflammation (Deyo & Weinstein, 2021). An acute lumbar sprain or strain typically presents with pain that worsens with movement, improves with rest, shows restricted range of motion in extension, rotation, and lateral flexion, and exhibits muscle tenderness upon palpation (Casiano, Sarwan, Dydyk & Varacallo, 2023).

• Disc herniation:

A herniated disc, also known as a slipped or ruptured disc, occurs when the nucleus pulposus (a soft, gel-like center) of an intervertebral disc pushes through a tear in the annulus fibrosus (the well-organized outer tissue of the disc) (Dydyk, Ngnitewe Massa & Mesfin, 2023).

Aging is a significant factor in disc herniation. The decline in proteoglycans (proteins that provide structural support) leads to disc dehydration and collapse. This places additional strain on the annulus fibrosus, creating tears and fissures that may allow the nucleus pulposus to herniate (Dydyk, Ngnitewe Massa & Mesfin, 2023).

Beyond lower back pain, disc herniation can cause neurological symptoms. These include radicular pain, sensory abnormalities (such as tingling, numbness, or burning), and motor weakness in the lower extremities, depending on which lumbar and sacral nerve roots are affected. These symptoms typically worsen with straining, coughing, sneezing, and sitting (Zhang, Xu, Ansari, Hardacker, Anderson, Alsoof & Daniels, 2023).