Introduction
A revision of the AO/OTA Fracture and Dislocation Classification was published in the January 2018 issue of the Journal of Orthopaedic Trauma (Compendium and support material). This module is organized according to the 2007 version. Please read through its revised classification (below) before returning to the AO Surgery Reference.
61A1 Intact posterior arch, innominate bone avulsion fracture
61A1.1 Anterior superior iliac spine fracture
61A1.2 Anterior inferior iliac spine fracture
61A1.3 Ischial tuberosity fracture
61A2 Intact posterior arch, innominate bone fracture
61A2.1 Iliac wing fracture
61A2.2 Unilateral fracture of the anterior arch
61A2.3 Bilateral fractures of the anterior arch
61A3 Transverse fracture of sacrum (S3, S4, S5) and coccyx
61A3 Transverse fracture of sacrum (S3, S4, S5) and coccyx
61B1 Incomplete disruption of posterior arch, no rotational instability
61B1.1* Lateral compression fracture (LC1)
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fracture
b - Bilateral pubic rami fracture
c - Contralateral pubic ramus fracture
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
61B1.2 Open book fracture (APC1)
61B2 Incomplete disruption of posterior arch, rotationally unstable, unilateral posterior injury
61B2.1* Lateral compression fracture of the sacrum with internal rotation instability (LC1)
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
c - Contralateral pubic ramus fractures
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
61B2.2* Lateral compression fracture of the ilium (crescent) with internal rotation instability (LC2)
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
c - Contralateral pubic ramus fractures
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
61B2.3* Open book or external rotation instability (APC2)
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
c - Contralateral pubic ramus fractures
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
61B3 Incomplete disruption of posterior arch, rotationally unstable, bilateral posterior injury
61B3.1* Internal rotationally unstable on one side and external rotationally unstable on the contralateral side (LC3)
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
61B3.2* Bilateral lateral compression sacral fracture
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
61B3.3* Open book or external rotation instability (bilateral APC2)
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
61C1 Complete disruption of posterior arch, unilateral posterior injury (APC3, vertical shear)
61C1.1* With iliac fracture
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
c - Contralateral pubic ramus fracture
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
j - Sacroiliac joint fracture dislocation
61C1.2* Through the sacroiliac joint
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
c - Contralateral pubic ramus fracture
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
j - Sacroiliac joint fracture dislocation
61C1.3* With a sacral fracture
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
c - Contralateral pubic ramus fracture
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
j - Sacroiliac joint fracture dislocation
61C2 Complete disruption of posterior arch, bilateral posterior injury, one hemipelvis injury complete disruption, contralateral hemipelvis injury incomplete disruption (LC3)
61C2.1* Complete disruption through ilium
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
c - Contralateral pubic ramus fracture
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
k - Contralateral posterior lateral compression lesion: sacrum
l - Contralateral posterior lateral compression lesion: ilium (crescent)
m - Contralateral posterior external rotation lesion: sacroiliac joint
n - Contralateral posterior external rotation lesion: fracture dislocation
61C2.2* Complete disruption through sacroiliac joint
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
c - Contralateral pubic ramus fracture
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
k - Contralateral posterior lateral compression lesion: sacrum
l - Contralateral posterior lateral compression lesion: ilium (crescent)
m - Contralateral posterior external rotation lesion: sacroiliac joint
n - Contralateral posterior external rotation lesion: fracture dislocation
61C2.3* Through the sacrum
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
c - Contralateral pubic ramus fracture
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
k - Contralateral posterior lateral compression lesion: sacrum
l - Contralateral posterior lateral compression lesion: ilium (crescent)
m - Contralateral posterior external rotation lesion: sacroiliac joint
n - Contralateral posterior external rotation lesion: fracture dislocation
61C3 Complete disruption of posterior arch, bilateral posterior injury, both sides complete disruption (APC3, vertical shear)
61C3.1* Extrasacral on both sides
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
c - Contralateral pubic ramus fracture
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
h - Iliac wing fracture
j - Sacroiliac joint disruption
61C3.2* Sacral one side, extra sacral other side
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
c - Contralateral pubic ramus fracture
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
h - Iliac wing fracture
j - Sacroiliac joint disruption
61C3.3* Sacral both sides
*Qualifications:
a - Ipsilateral or unilateral pubic ramus fractures
b - Bilateral pubic rami fractures
c - Contralateral pubic ramus fracture
d - Symphysis disruption
e - Parasymphyseal fracture
f - Tilt fracture
g - Locked symphysis
h - Iliac wing fracture
j - Sacroiliac joint disruption
