The gluteus minimus is one of the three primary gluteal muscles, working alongside the gluteus medius and gluteus maximus to control movement and stability in the lower body. Despite its name, it plays a significant role in hip function. This muscle is a major contributor to overall hip mechanics, influencing everything from walking posture to athletic performance. Understanding its function is important for grasping the complete picture of hip health and movement.
Where the Gluteus Minimus is Located
The gluteus minimus is the deepest of the three gluteal muscles, positioned directly underneath the gluteus medius and the gluteus maximus. Because of this layering, the minimus is not externally palpable, as it is tucked close to the hip joint. Its fan-shaped structure originates from the outer surface of the ilium, the wide, upper bone of the pelvis. Specifically, it arises from the area between the anterior and inferior gluteal lines.
Its fibers converge to form a tendon that extends downward toward the femur (thigh bone). The insertion point for this tendon is the anterior part of the greater trochanter, a prominent bony ridge on the upper, outer side of the femur. This attachment point is shared with the gluteus medius. The muscle’s deep location and connection between the pelvis and the upper femur make it a powerful stabilizer of the hip.
Essential Movements Controlled by the Muscle
The gluteus minimus works with the gluteus medius to perform two primary actions at the hip joint: abduction and internal rotation. Hip abduction is the movement of the leg away from the center of the body, such as when stepping sideways or lifting the leg out to the side. The anterior fibers of the muscle are particularly active in pulling the thigh inward, initiating internal rotation of the hip.
A primary function of this muscle is its role in dynamic stability, especially during single-leg stance activities like walking or running. When a person stands on one leg, the gluteus minimus on the supporting side contracts to keep the pelvis level. This action prevents the pelvis from dropping on the side of the lifted leg. By stabilizing the pelvis, the muscle ensures proper alignment of the entire lower limb, which is crucial for efficient movement and injury prevention.
When the Gluteus Minimus Causes Pain
When the gluteus minimus becomes dysfunctional, it can lead to gluteal tendinopathy, a common cause of lateral hip pain. This condition involves the tendon where the muscle attaches to the greater trochanter of the femur. It is often misdiagnosed as trochanteric bursitis or sciatica. Pain is typically felt over the outer hip area and may radiate down the outside of the thigh toward the knee.
A common finding with gluteus minimus weakness is the Trendelenburg sign, a specific gait abnormality. This sign is observed when a person lifts one leg and the pelvis drops down on the side of the lifted leg. This indicates the hip abductor muscles on the stance leg are unable to keep the pelvis level. The resulting gait pattern, known as the Trendelenburg gait, involves the person shifting their body weight over the weak hip to compensate.
Pain may also originate from myofascial trigger points within the muscle belly, which are tight, hypersensitive knots of tissue. These trigger points cause referred pain, meaning discomfort is felt in an area distant from the muscle. Trigger points in the minimus frequently refer pain deep into the buttock, down the posterior thigh, and sometimes into the calf, mimicking true sciatica. Accurate diagnosis, often involving physical examination and imaging, is needed to differentiate gluteal tendinopathy from other sources of hip or back pain.