The lumbar spine, particularly the L4 and L5 vertebrae just above the sacrum, supports significant upper body weight and facilitates movement. Problems in this heavily loaded and flexible area can sometimes cause pain in distant locations, including the hip.
Understanding the Spinal-Hip Connection
Nerves from the lower back link the spine and hip, with nerves like the femoral, obturator, and sciatic emerging from spinal segments, including L4 and L5, extending into the pelvis, hip, and legs. The femoral nerve (L2-L4) controls hip flexors and provides sensation to the front thigh and knee. The sciatic nerve, the body’s largest nerve, is formed by nerve roots from L4 through S3, traveling from the lower back, through the buttocks, and down each leg, delivering both sensory and motor signals. Pain originating from the spine can be perceived in the hip or leg due to referred pain, which occurs because sensory nerves from different areas, such as the lower back and hip, converge in the same spinal cord region, causing the brain to misinterpret the true source of discomfort.
Specific L4 and L5 Conditions Linked to Hip Pain
Several conditions affecting the L4 and L5 vertebrae can cause referred hip pain by impacting spinal nerves. Lumbar disc herniation, where disc material pushes through its outer ring, compresses nearby nerve roots; herniations at L4-L5 or L5-S1 can affect L5 or S1 roots (components of the sciatic nerve), leading to pain that radiates from the lower back into the hip, buttock, and down the leg, often described as a burning or shooting sensation. Spinal stenosis, a narrowing of the spinal canal, can also irritate or compress the nerves traveling through the L4-L5 region, causing similar radiating pain into the hip and legs. Spondylolisthesis involves one vertebra slipping forward over another (common at L4-L5 or L5-S1), putting direct pressure on spinal nerves, resulting in hip pain, numbness, or tingling down the leg; facet joints, which connect adjacent vertebrae, can also develop arthritis, leading to localized back pain referred to the hip area.
How to Identify Spinal-Related Hip Pain
Distinguishing hip pain originating from the spine versus the hip joint itself often relies on the pain’s characteristics and accompanying symptoms. Spinal-related hip pain, especially from L4 or L5 nerve irritation, frequently presents as pain that radiates from the lower back, through the buttock, and down the leg (often called sciatica), and can include sensations like numbness, tingling, or weakness along the nerve’s path. Pain stemming from spinal issues may worsen with certain movements that affect the spine, such as bending, twisting, or prolonged sitting. In contrast, pain originating from the hip joint is typically more localized to the groin, outer hip, or buttock, worsening with movements directly involving the hip joint, like walking, bearing weight, or rotating the leg; foot weakness or changes in sensation in specific parts of the leg or foot further suggest spinal nerve involvement.
When to Consult a Healthcare Professional
Persistent hip pain, especially if radiating or accompanied by other symptoms, warrants a medical evaluation; early diagnosis helps identify the cause for appropriate management, and healthcare professionals can conduct an examination and may recommend imaging to determine if the pain stems from L4 or L5 spinal issues. Seek immediate medical attention if hip pain is severe, rapidly worsening, or accompanied by “red flag” symptoms, such as new or progressive weakness in the legs, loss of sensation in the saddle area (buttocks, genitals, inner thighs), or any changes in bladder or bowel control, as these could indicate a serious condition like cauda equina syndrome, requiring urgent intervention to prevent permanent neurological damage.