PELVIS

GENERAL INFORMATION

The pelvis is a bony structure located between the spine and the legs, forming the base of the spine and supporting the abdominal organs. It plays a vital role in weight-bearing, locomotion and protecting pelvic organs such as the bladder, intestines and reproductive organs.

ORIGIN

The pelvis is composed of three prominent bones:

• Ilium: The large, fan-shaped part of the pelvis.
• Ischium: The lower, curved bone at the base of the pelvis.
• Pubis: The front part of the pelvis that forms the pubic region.

INSERTION POINT

The pelvis has no specific insertion point, as it is a bony structure that supports and anchors various muscles and ligaments rather than functioning like a muscle with an origin and insertion.

MAJOR ARTERIES

The major arteries supplying the pelvis include:

• Internal iliac artery: Provides blood to the pelvic organs, gluteal muscles and reproductive structures.
• Superior gluteal artery: Supplies blood to the muscles and skin in the gluteal region.

NEURAL INNERVATION

The pelvis receives innervation from the following:

• Sacral plexus: A network of nerves responsible for motor and sensory functions in the pelvis, buttocks and lower limbs.
• Pudendal nerve: Controls the external genitalia and pelvic floor muscles, crucial for continence and sexual function.

TRIGGER POINT

The pelvis does not develop trigger points, but the muscles surrounding it, such as the gluteals and hip flexors, can develop painful trigger points from overuse or injury.

CONCENTRIC FUNCTION

Muscles around the pelvis, such as the gluteus maximus and hip flexors, contract concentrically to produce movements like walking, running and lifting.

ECCENTRIC FUNCTION

Eccentric muscle contractions around the pelvis, such as in the hamstrings and quadriceps, help control movements like sitting down and decelerating after a jump or sprint.

ISOMETRIC FUNCTION

Muscles surrounding the pelvis, such as the core muscles and gluteals, engage isometrically to stabilise the pelvis during activities like standing, walking and maintaining posture.

RELATED MUSCLES SCIENTIFIC NAMES

• Gluteus Maximus: Responsible for hip extension and external rotation, aiding in upright posture and powerful movements like jumping and running.
• Iliopsoas: A primary hip flexor that lifts the leg and helps stabilise the pelvis during walking.
• Piriformis: A small muscle that aids in the external rotation of the hip and stabilises the pelvis during leg movements.
• Rectus Abdominis: It helps stabilise the pelvis and flex the trunk, assisting in maintaining core strength and posture.
• Adductor Magnus: Responsible for hip adduction, assisting in stabilising the pelvis during leg movements.

ANTAGONIST

• Hamstrings: Act against the quadriceps by allowing knee flexion and controlling hip extension.
• Quadriceps: Oppose the hamstrings, assisting in hip flexion and stabilising the pelvis during leg extension.
• Gluteus Medius: Acts against the adductors by aiding in hip abduction and stabilising the pelvis during lateral movements.
• Erector Spinae: Opposes the forward flexion of the spine, supporting pelvic stability and extension of the spine.
• Obliques: Work against the rectus abdominis by helping rotate and laterally flex the spine, stabilising the pelvis during dynamic movements.

COMMON INJURIES

• Pelvic Fractures: Resulting from trauma, leading to severe pain and immobility. These fractures can affect weight-bearing ability and require significant rehabilitation.
• Hip Labral Tear: A tear in the cartilage surrounding the hip joint, causing pain and instability. This injury often results from repetitive stress or traumatic injury.
• Piriformis Syndrome: Occurs when the piriformis muscle irritates the sciatic nerve, causing pain in the buttocks and down the leg.
• Hip Flexor Strain: Results from overstretching or tearing the iliopsoas, causing sharp pain and limited mobility in the hip area.
• Sacroiliac Joint: Dysfunction occurs when the SI joint becomes inflamed or misaligned, causing lower back and pelvic pain.

EXERCISES

• Glute Bridges: Strengthens the gluteus maximus and hamstrings by lifting the hips off the ground, promoting pelvic stability and strength.
• Pelvic Tilts: Helps engage the core and improve flexibility by gently tilting the pelvis forward and back while lying on the floor.
• Clamshells: Targets the gluteus medius by rotating the hip externally while lying on the side, improving lateral pelvic stability.
• Bird-Dog: Engages the core and stabilises the pelvis by extending opposite limbs while on hands and knees, improving balance and strength.
• Hip Flexor March: Strengthens the iliopsoas by lifting the legs individually while maintaining core stability and enhancing hip flexor control.

STRETCHES

• Seated Forward Fold: Stretches the hamstrings and lower back by reaching forward while seated, releasing tension in the pelvis and spine.
• Hip Flexor Stretch: Targets the iliopsoas by lunging forward, deepening the stretch to enhance hip mobility.
• Piriformis Stretch: Lying on the back and crossing one leg over the other, this stretch alleviates pressure on the sciatic nerve and relieves piriformis tension.
• Butterfly Stretch: Stretches the inner thighs and groin by bringing the feet together and pressing the knees down, improving pelvic flexibility.
• Figure Four Stretch: Performed by crossing one ankle over the opposite knee, this stretch helps release tension in the glutes and pelvic muscles.