If you’ve attended one of our clinics at Optimum Health Solutions, chances are you have prescribed exercises specifically targeting the ‘glutes,’ or you’ve been cued to ‘squeeze your bum muscles’. The reason being that the glutes are an important group of muscles involved in many functions at the hip, which are required for optimal functioning of activities in daily living, injury rehabilitation, injury prevention, and sporting performance.
Functional Anatomy
The group known as the ‘gluteals’ are made up of 3 muscles – gluteus maximus, gluteus medius, and gluteus minimus – and as a whole, are able to control the upper and lower body in multiple planes of movement. As you may already know, the largest muscle in the body is the gluteus maximus, which is responsible for extending the leg at the hip (moving the leg posteriorly), tilting the pelvis posteriorly, and it contributes to externally rotating the leg at the hip (turning the leg outward).
Being approximately half the weight of the gluteus maximus, the gluteus medius is surprisingly large and is responsible for hip abduction (moving the leg laterally away from the body). To a lesser extent, it’s also responsible for internal and external rotation of the leg at the hip (turning the leg inward and outward). The gluteus medius also functions as an important hip joint stabiliser, particularly important during gait, ensuring the pelvis does not drop laterally. Weakness in this muscle has been implicated in many musculoskeletal conditions.
The smallest of the 3, and with the least responsibility, is the gluteus minimus. This abducts the thigh alongside the gluteus medius when the limb is extended. It is specifically recruited into action for supporting the body on one limb.
Pathology
Weak or dysfunctional activation of the gluteal muscles can contribute to musculoskeletal injury, plus lower back and joint pain in the lower extremities, through instability in the pelvis and core. Often referred to as gluteal amnesia, an individual may not have the ability to activate the glutes, in order to drive movement or provide the stability required for a specific function. Instead, this movement is achieved via recruitment of other muscles, often leading to over activity in these muscles, incorrect mechanics, and finally musculoskeletal injury.
Some examples of lower limb pathologies, where such compensations can occur, are as follows:
- Anterior Cruciate Ligament (ACL) injury. An important predictor of ACL injury, particularly in females, is ‘knee valgus’ (the knees caving inward). Excessive knee valgus has been linked to gluteus medius weakness, by way of reduced hip abduction strength, therefore inability to stabilize the pelvis laterally. If a knee valgus is present, it is generally evident during a squat movement.
- Lateral hip pain, tears and avulsive injuries. In older adults, such pathologies have been linked with atrophy (reduced muscle mass) of the gluteus medius muscle, predisposing the individual to injuries of this nature.
- Dysfunction and instability of the Sacroiliac Joint (SIJ): The SIJ is the point at which the lower portion of the vertebrae connects with the pelvis. It can be irritated by dysfunctional glutes that cannot provide efficient stability. As a major attachment of gluteus maximus crosses the sacrum, therefore if functioning optimally, is able to provide pelvic stability. Dysfunction of the SIJ contributes towards 25% of lower back pain complaints.
- Patellofemoral Pain Syndrome (PFPS). Poor gluteus medius function and subsequent poor hip mechanics can contribute to PFPS through altered tracking of the patella, and atrophy of the quadriceps, causing anterior knee pain.
- Poor recovery following total knee and total hip replacement surgeries. Recovery time can be dramatically shortened if retraining of the gluteals occurs. As mentioned above, the glutes are important hip joint stabilizers. When the hips are functioning correctly, this ensures that during movement, any load is dispersed evenly across the joints, not solely at the knees or hips, thus enhancing recovery and reducing risk of injury.
- Other pathologies. LBP (through over activity or lack of muscular endurance), ITB syndrome, and various overuse injuries in the lower back, hip, knee, and ankle.
The Exercise Physiologist
Whether you find yourself in a situation where you’ve obtained one of the above injuries, or are undertaking exercise as part of weight loss, disease management, or even a sporting performance program, effective gluteal function is essential to ensure efficient recovery, function, optimal and safe performance.
An assessment can be performed by your Exercise Physiologist, in collaboration with a Physiotherapist (if required). This will help determine any biomechanical deficiencies present, and your level of gluteal function, to prescribe your individualised exercise prescription required to achieve your goals.
