Basics
Description
- They occur in 45% of all pelvic fractures and are rarely isolated
- They are defined by the orientation of the fracture line.
- Mechanism:
- Axial compression
- Direct posterior trauma
- Massive crush injury
- Insufficiency fractures in elderly and osteoporotic patients
Fracture Classification
Transverse
- Above S4:
- Neurologic injury common
- Can see cauda equina syndrome (CES)
- Below S4:
- Associated rectal tears
- Neurologic injury is are
Vertical
- Lateral to sacral foramina:
- Sciatica
- L5 root injury
- Neurologic deficit infrequent
- Foraminal (zone 2):
- Bowel/bladder dysfunction
- L5, S1, S2 root injury
- Neurologic deficit frequent
- Canal (zone 3):
- Bowel/bladder dysfunction
- Sexual dysfunction
- L5, S1 root injury
- Neurologic deficit often present (>50%)
Etiology
- Transverse: Fall from height, flexion injuries, direct blow
- Vertical: Usually high-energy mechanism
Sacral insufficiency fractures should be considered in elderly patients with severe back pain
Diagnosis
Signs and Symptoms
- Pain in buttocks, perirectal area, and posterior thigh
- Swelling and ecchymosis over the sacral prominence
- Possible sacral nerve dysfunction:
- Absent or diminished anal sphincter tone is an important finding.
- Bowel or bladder incontinence
Essential Workup
- History and physical exam with attention to loss of anal sphincter tone, sensation in the perineum, and bowel and bladder sphincter control.
- Sacral fractures rarely occur in isolation; look for associated injuries.
- Rectal exam will elicit pain in the sacrum; blood in the rectum suggests an open fracture.
Diagnosis Tests & Interpretation
Imaging
- Only 30% of sacral fractures are detected on plain radiograph.
- CT provides optimal imaging to identify sacral fractures.
- MRI is indicated when neurologic dysfunction is present.
Differential Diagnosis
- Contusion
- Lumbar spine fracture
- Pelvic fractures
Treatment
Pre-Hospital
- Sacral fractures are frequently associated with other spinal and intra-abdominal injuries.
- Immobilize with backboard and C-spine collar.
Initial Stabilization/Therapy
- Manage ABCs as needed.
- Early immobilization in unstable pelvis or spine fractures
- Pain control with NSAIDs or narcotic analgesics
Ed Treatment/Procedures
- Vertical unstable fractures require a rapid and thorough assessment for life-threatening injuries as well as orthopedic consultation (see "Pelvic Fracture " ).
- Nondisplaced isolated transverse sacral fractures are treated symptomatically with touch-down weight bearing on affected side and early orthopedic referral.
- Surgery is often required for fractures associated with neurologic injury.
Medication
First Line
Analgesia as indicated
Follow-Up
Disposition
Admission Criteria
- Critically injured trauma patient with unstable pelvic fracture
- Neurologic impairment requires orthopedic consultation.
Discharge Criteria
- Isolated nondisplaced sacral fractures
- Consider intermediate or assisted-care setting for elderly patients.
Follow-Up Recommendations
- Only nondisplaced, transverse fractures are appropriate for outpatient follow-up
- Prompt surgical evaluation is indicated for displaced fractures.
Pearls and Pitfalls
- Sacral fractures are rarely isolated; consider associated pelvic fractures.
- Detailed neurologic exam, including rectal sphincter tone and perianal sensation, is indicated to assess for associated sacral nerve root injury.
- Foley catheter in a trauma patient may mask voiding problems from sacral nerve root injury.
Additional Reading
- Choi SB, Cwinn AA. Pelvic trauma. In: Rosen P, ed. Emergency Medicine: Concepts and Clinical Practice. 7th ed. Philadelphia, PA: Mosby-Elsevier; 2009.
- Galbraith JG, Butler JS, Blake SP, et al. Sacral insufficiency fractures: An easily overlooked cause of back pain in the ED. Am J Emerg Med. 2011;29(3):359.e5 " e6.
- Hak DJ, Baran S, Stahel P. Sacral fractures: Current strategies in diagnosis and management. Orthopedics. 2009;32:752 " 757.
See Also (Topic, Algorithm, Electronic Media Element)
Pelvic Fracture
Codes
ICD9
- 733.13 Pathologic fracture of vertebrae
- 805.6 Closed fracture of sacrum and coccyx without mention of spinal cord injury
- 806.62 Closed fracture of sacrum and coccyx with other cauda equina injury
- 806.69 Closed fracture of sacrum and coccyx with other spinal cord injury
- 806.61 Closed fracture of sacrum and coccyx with complete cauda equina lesion
ICD10
- M84.48XA Pathological fracture, other site, init encntr for fracture
- S32.10XA Unsp fracture of sacrum, init encntr for closed fracture
- S32.14XA Type 1 fracture of sacrum, init encntr for closed fracture
- S32.119A Unsp Zone I fracture of sacrum, init for clos fx
- S32.129A Unsp Zone II fracture of sacrum, init for clos fx
- S32.139A Unsp Zone III fracture of sacrum, init for clos fx
SNOMED
- 125872003 Fracture of sacrum (disorder)
- 441881007 Stress fracture of sacrum (disorder)
- 207974008 Closed fracture sacrum (disorder)
- 208071000 Closed fracture of sacrum with complete cauda equina lesion (disorder)
- 207975009 Closed compression fracture sacrum (disorder)
- 207976005 Closed vertical fracture of sacrum (disorder)