Musculoskeletal

1. Sacrum
2. Ischium
3. Gluteus Maximus
4. Gluteus Medius

2. Position 2

1. Ilium
2. Gluteus Maximus
3. Gluteus Medius

1. Position 1

1. Sacrum
2. Ischium
3. Inferior Gluteal Artery

3. Position 3

1. Sacrum
2. Ischium
3. Greater Sciatic Notch or Foramen
4. Superior Gluteal Artery

2. Position 2

1.  Ilium

1. Position 1