Superior Gluteal Nerve Injury (L4-S1)
Overview
Plain-Language Overview
The Superior Gluteal Nerve Injury (L4-S1) affects the nerve that controls important muscles in the hip, including the gluteus medius and gluteus minimus. This nerve injury can cause weakness in these muscles, leading to difficulty with movements like walking or standing on one leg. People with this condition often experience a characteristic limp called the Trendelenburg gait, where the pelvis drops on the side opposite the injury. The injury involves the nervous system, specifically the peripheral nerves that connect the spinal cord to the hip muscles. This condition can result from trauma, surgery, or compression near the pelvis. Overall, it impacts mobility and balance, making everyday activities more challenging.
Clinical Definition
Superior Gluteal Nerve Injury (L4-S1) is a peripheral neuropathy involving damage to the superior gluteal nerve, which arises from the L4-S1 nerve roots. The nerve innervates the gluteus medius, gluteus minimus, and tensor fasciae latae muscles, which are critical for hip abduction and pelvic stabilization during gait. Injury typically results from pelvic trauma, iatrogenic causes such as hip surgery, or compression by masses or hematomas. Clinically, this injury manifests as weakness in hip abduction, a positive Trendelenburg sign, and an abnormal gait pattern. The condition is significant because it impairs pelvic stability, increasing fall risk and functional disability. Electrophysiological studies and imaging can help localize the lesion and exclude other causes.