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20.3 ­FractFres ofctrf Hip reH o 353

part and are more extensive than the ventral SI ligaments, which are composed of many short,
fibrous fascicles that are arranged in two groups. Those of the cranial ventral group run medially
and caudally from the ilium to the sacrum. Those of the shorter caudal ventral group run medially
and cranially. The thin joint capsule appears between them.

20.3 Fractures of the Hip Region

Fractures of the pelvis occur commonly with motor vehicle trauma or other high energy traumas
such as falling from a height. Fractures can occur to the pelvic bones, SI joint, or the coxofemoral
joint itself – fractures of the femoral head, femoral neck, and acetabulum.
Dogs will typically present non-weight-bearing on the affected limb, or possibly laterally recum-
bent depending upon concurrent injuries. Patient stabilization is the primary objective before any
orthopedic issues are addressed, as many dogs with such trauma will have concurrent injuries (e.g.
pneumothorax, pulmonary contusions, and urogenital injury).
Orthogonal radiographs should be obtained under heavy sedation or general anesthesia to con-
firm the presence of fracture(s) and to assess the fracture anatomy. The pelvis can be considered a
rigid box-like structure, with fractures commonly occurring in specific locations and patterns.
Because of this box-like structure, for there to be displacement the pelvis must fracture in at least
three places. However, because SI luxation may also act like a fracture, displacement can occur
under that scenario (e.g. pubic and ischial fracture in combination with SI luxation would also
allow for displacement; Figure 20.3). CT may be indicated in cases of acetabular factures or more
complex cases and may be combined to assess for comorbidities.

20.3.1 SI Joint Luxation and Sacral fractures

Sacroiliac luxation-fracture (SIL/F) denotes traumatic separation of the ilial wing from the sacrum
(Figure 20.4). As with fractures of the pelvis, for displacement to occur several other fractures or
luxations must be present, unless bilateral luxation is present with an intact pelvis. The iliac wing HIP REGION
will typically displace cranially and dorsal to the sacrum due to the pull of attached musculature.
While SIL/F can involve a small portion of the sacral wing fracturing, this should be differentiated
from a true sacral fracture (Figure 20.5), where the sacral bone is significantly involved. Cases of
sacral fracture are typically more painful than SIL/F, and dogs will commonly have neurologic
deficits unlike those with simple SIL/F. If such signs are noted on physical exam, sacral fracture
should be considered. CT imaging elucidates the extent of damage more readily than survey radio-
graphs. SIL/F can be treated surgically or nonsurgically (Fauron and Déjardin 2018). Considerations
to include in selection of treatment include patient level of pain, degree of instability of the pelvis,
and amount of narrowing of the pelvic canal.

20.3.2 Fractures of the Ilium

Fractures of the ilium are most commonly long oblique fractures oriented from cranioventral to
caudodorsal (Figure 20.3). While most are midbody, they can also extend cranially involving a
portion of the SI joint, or caudally over the dorsal aspect of the acetabulum (not involving the
joint). Ilial fractures are generally accompanied by fractures of the ischium and pubis, which are
generally not treated surgically. Treatment can be surgical or nonsurgical and usually depends on
displacement.