GENERAL INFORMATION
The iliopsoas are a group of muscles located in the hip region. The combination of the iliacus and psoas major muscles forms it. The iliopsoas is one of the primary hip flexors and plays a crucial role in various movements, including walking, running, and sitting.
ORIGIN
- Iliacus: Originates from the iliac fossa, which is a concave surface on the inside of the iliac bone.
- Psoas Major: Originates from the lumbar vertebrae (T12-L5) and their intervertebral discs.
INSERTION POINT
Both the iliacus and psoas major muscles merge and are inserted into the lesser trochanter of the femur, which is a bony prominence on the inner aspect of the thigh bone.
MAJOR ARTERIES
The iliopsoas muscle receives its blood supply from branches of the iliac arteries, including the iliolumbar artery and the deep circumflex iliac artery.
NEURAL INNERVATION
The iliopsoas muscle is innervated by the femoral nerve (L2-L4), which provides sensory and motor innervation to the lower limb.
TRIGGER POINT
Trigger points in the iliopsoas muscle can cause pain and discomfort in the hip, lower back, and groin region.
CONCENTRIC FUNCTION
During contraction, the iliopsoas muscle acts to flex the hip joint, bringing the thigh bone closer to the torso.
ECCENTRIC FUNCTION
The eccentric function of the iliopsoas muscle occurs during the controlled lengthening of the muscle, such as during the lowering phase of a squat or lunge.
ISOMETRIC FUNCTION
The iliopsoas muscle can contract isometrically to stabilise the pelvis and maintain hip joint stability.
RELATED MUSCLE-SCIENTIFIC NAMES
- Iliacus: A primary hip flexor originating from the iliac fossa.
- Psoas Major: A major hip flexor originating from the lumbar vertebrae.
ANTAGONIST MUSCLES
- Gluteus Maximus: Responsible for hip extension and counteracts the hip flexion action.
- Hamstrings (e.g., Biceps Femoris, Semitendinosus, Semimembranosus): Involved in knee flexion and hip extension, opposing the iliopsoas muscle group.
COMMON INJURIES
- Strains or tears: Overstretching or excessive contraction can lead to muscle fibre damage.
- Hip flexor tendinitis: Inflammation of the tendons due to overuse or repetitive stress.
- Muscle imbalances: This can lead to pelvic instability and associated lower back pain.
EXERCISES
- Hip flexion exercises: Leg raises, knee raises, and hip flexor stretches help strengthen and stretch the iliopsoas.
- Squats and lunges: Engage the iliopsoas along with other hip and leg muscles for overall strength.
- Pilates exercises: Target the hip flexors and core muscles for improved stability and flexibility.
STRETCHES
- Kneeling hip flexor stretch: Stretches the iliopsoas and helps improve hip flexibility.
- Supine figure-four stretch: Targets the hip and lower back muscles.
- Seated butterfly stretch: Opens up the hips and stretches the inner thighs.
- Pigeon pose (variation): A yoga pose that deeply stretches the hip flexors and glutes.