A pelvis fracture occurs when one or more of the bones forming the pelvic ring break. The pelvis is made up of several bones including the ilium, ischium, and pubis, which form a ring structure.

Pelvic fractures may occur from:

• Falls, especially in older adults
• Motor vehicle accidents
• High-impact sports injuries
• Direct trauma to the hip or pelvis

An acetabular fracture is a break in the acetabulum, the socket portion of the hip joint where the femoral head (top of the thigh bone) fits.

Because the acetabulum forms the hip joint, these fractures can significantly affect hip stability and movement.

Acetabular fractures are most often caused by:

• Motor vehicle accidents
• High-energy trauma
• Falls from height
• Sports injuries

The sacroiliac (SI) joints connect the sacrum (base of the spine) to the pelvic bones. Injuries to this area can involve fractures of the sacrum or disruptions of the sacroiliac joint.

Sacroiliac fractures often occur with pelvic trauma and may result from:

• Motor vehicle accidents
• Falls from height
• High-energy injuries
• Severe sports trauma