Many conditions can cause upper leg and back pain. According to the Spine Health website, back pain, especially lower back pain, is commonly associated with one-sided leg pain. Leg pain that accompanies back pain may be dull and aching or sharp and stabbing, like an electrical shock. Although simultaneous back pain and upper leg pain may be caused by separate musculoskeletal problems, they are often related problems. Most conditions involving upper leg and back pain respond well to conservative care methods.
Lumbar Disk Herniation
A lumbar disk herniation is a common cause of upper leg and back pain, especially in young to middle-aged individuals. It occurs when a small portion of the disk's center, known as the nucleus pulposus, ruptures through a crack or fissure in the disk's fibrous outer ring and protrudes into the spinal canal. The ruptured, or herniated, disk material can compress or irritate nerve roots—spinal cord offshoots—in the lumbar spine, or lower back. Common signs and symptoms associated with a lumbar disk herniation include lower back pain that radiates into the buttocks and the upper leg; numbness; tingling and weakness in the back of the affected-side leg; and lower back pain that is worse with sitting, coughing or sneezing. MayoClinic.com states that smoking, obesity and a tall stature are risk factors associated with lumbar disk herniations.
Trigger points are discrete, focal hyper-sensitive knots located in a taut band of muscle that can cause pain in the upper leg and back. Although trigger points can manifest in any skeletal muscle throughout the body, they are commonly found in the back and upper thigh. Trigger points, when pressed, generate local and referred pain, or pain that arises in another part of the body. According to the American Academy of Family Physicians, trigger points usually accompany chronic musculoskeletal disorders. Other possible causes of trigger points in the upper leg and back include poor posture, blunt-force trauma and repetitive strain injuries. Any condition that causes the muscle fibers to bear excess strain may cause trigger points. The AAFP states that trigger points can be active or latent. An active trigger point causes pain at rest, whereas a latent trigger point does not cause spontaneous pain, but it may impair movement and cause muscle weakness.
Ankylosing spondylitis is an inflammatory condition that can cause upper leg and back pain. According to the Spondylitis Association of America, or SAA, ankylosing spondylitis, also known as spondylitis or rheumatoid spondylitis, is a type of arthritis that affects the spine and hips, causing chronic pain or discomfort in the back and upper leg. Although there is no known cause of ankylosing spondylitis, genetic factors, which include having the HLA-B27 gene, may play a role. Common signs and symptoms associated with ankylosing spondylitis include chronic pain in the lower back and hips; pain in affected areas that is worse in the morning or following periods of physical activity; pain at the entheses, or locations where tendons and ligaments attach to bone; and pain and inflammation in the eyes. The SAA states that, although there is no cure for ankylosing spondylitis, current treatment approaches can help reduce symptoms and manage pain.