›If new bowel incontinence, urgent spine surgery consultation
›Open injury pathway
›If open wound near sacrum or perineum, open fracture protocol
›If gross contamination, broaden antibiotics and urgent operative washout planning
›High-risk associated injuries
›Pelvic ring injury coexistence
›If posterior pelvic pain with instability, treat as pelvic ring until proven otherwise
›If unable to mobilize or severe pain, CT pelvis priority
›Urogenital injury risk
›If blood at meatus or perineal ecchymosis, urethral injury precautions
›If gross hematuria, bladder injury evaluation
Limb threat and neurovascular documentation
›Neurovascular baseline and repeat checks
›Lower extremity pulses
›Dorsalis pedis pulse
›Posterior tibial pulse
›Motor and sensory domains
›L4 knee extension
›L5 great toe extension
›S1 plantarflexion
›S2-S4 perianal sensation
›Documentation timepoints
›Pre-immobilization baseline
›Post-analgesia and after any repositioning
02History/hx29
Mechanism and timeline
›Injury context
›Mechanism category
›High-energy trauma
›Low-energy fall
›Repetitive stress
›Impact pattern
›Direct blow to buttocks
›Axial load through spine
›Time course
›Time since injury
›Pain trajectory over time
Red flags and functional impact
›Neurologic and pelvic organ symptoms
›Cauda equina features
›Urinary retention
›Saddle anesthesia
›New bowel dysfunction
›Radicular symptoms
›Sciatica pattern pain
›New numbness or weakness
›Functional limitation
›Ability to ambulate
›Pain with sitting
›Risk modifiers
›Bone health risks
›Osteoporosis or fragility fracture history
›Chronic glucocorticoids
›Bleeding risk
›Anticoagulants
›Platelet dysfunction or liver disease
03Physical Exam/exam39
General and pelvic stability
›Global assessment
›Vital signs and shock indicators
›Persistent tachycardia
›Hypotension
›Pelvic stability precautions
›Avoid repeated pelvic compression maneuvers
›Binder position check over greater trochanters
›Inspection and palpation
›Skin and soft tissue
›Ecchymosis over sacrum or perineum
›Laceration near sacrum or perianal region
›Tenderness localization
›Midline sacral tenderness
›Coccygeal point tenderness
Neurologic and rectal focused exam
›Lumbosacral neurologic exam
›Motor testing
›Hip flexion
›Knee extension
›Ankle dorsiflexion
›Great toe extension
›Sensory testing
›L4 medial leg
›L5 dorsum foot
›S1 lateral foot
›S2-S4 perianal sensation
›Pelvic floor screening
›Rectal exam indicators
›If cauda equina concern, anal tone
›If open injury concern, gross blood
›Bladder distention clues
›Suprapubic fullness
›Inability to void
PITFALLS
›Common misses
›Normal radiograph does not exclude sacral fracture
›Occult fractures common in older adults and insufficiency patterns
›Coccyx pain with normal imaging may still be fracture or dislocation
›Management remains symptom-guided
›Neurologic deficits can be subtle early
›Repeat exams after analgesia and over time
04Differential Diagnosis/ddx35
Traumatic causes
›Fracture and dislocation spectrum
›Sacral fracture (ICD-10 S32.1)
›Denis zone I lateral to foramina
›Denis zone II through foramina
›Denis zone III central canal
›Coccyx fracture (ICD-10 S32.2)
›Fracture without dislocation
›Fracture with displacement
›Coccyx dislocation (ICD-10 S33.2)
›Anterior subluxation
›Posterior subluxation
›Pelvic ring injury (ICD-10 S32.8)
›Sacroiliac disruption
›Pubic rami fractures
›Neurologic emergencies
›Cauda equina syndrome (ICD-10 G83.4)
›Urinary retention and saddle anesthesia
›Progressive bilateral leg symptoms
Non-traumatic and mimics
›Insufficiency and stress conditions
›Sacral insufficiency fracture
›Osteoporosis risk profile
›Minimal trauma onset
›Stress fracture
›Endurance activity
›Progressive pain with load
›Pain mimics
›Lumbar radiculopathy
›Dermatomal pain pattern
›Positive straight leg raise
›Sacroiliac joint dysfunction
›Pain provoked by SI maneuvers
›Minimal focal bony tenderness
›Coccydynia without fracture
›Pain with sitting
›Normal neuro exam
05Laboratory Tests/lt20
Trauma and bleeding assessment
›Baseline labs when high-energy or admission likely
›Complete blood count for occult bleeding
›Hemoglobin trend
›Leukocytosis interpretation with stress response
›Electrolytes and renal function
›Sodium mmol/L
›Potassium mmol/L
›Coagulation studies when anticoagulated or bleeding risk
›INR
›aPTT
›Type and screen when pelvic ring injury or shock concern
›Massive transfusion protocol readiness
›Crossmatch triggers with ongoing instability
Infection and open injury considerations
›Open fracture or contaminated wound labs
›Lactate mmol/L in shock concern
›Serial trend for resuscitation response
›False elevation with seizures or beta agonists
›Creatine kinase when crush or prolonged immobilization concern
›Rhabdomyolysis risk
›Renal protection planning
06Diagnostic Tests/dt51
Scoring Systems
›Sacral fracture classification
›Denis zones
›Zone I typically lower neurologic risk
›Zone II higher nerve root risk
›Zone III highest central canal risk
›AO Spine sacral classification
›Morphology guides stability and operative planning
›Neurologic status modifiers for urgency
›Pelvic ring stability context
›Stable patterns
›Isolated coccyx fracture or dislocation
›Isolated low-energy nondisplaced sacral fracture
›Unstable patterns
›Sacral fracture with pelvic ring disruption
›Displacement or vertical shear features
Radiographs
›Initial radiographs
›Pelvis radiograph
›Anteroposterior pelvis
›Inlet and outlet views if pelvic ring concern
›Sacrum and coccyx views when available
›Lateral sacrum and coccyx
›Limited sensitivity for nondisplaced fractures
›Post-intervention imaging
›After any reduction attempt of coccygeal dislocation
›Lateral view alignment check
›Symptom response correlation
MRI
›Indications
›Suspected sacral insufficiency fracture with negative CT or radiograph
›Bone marrow edema confirmation
›Multilevel stress injury mapping
›Neurologic deficit or cauda equina concern
›Canal compromise evaluation
›Nerve root compression localization
›Limitations
›Availability constraints in unstable trauma
›CT preferred in acute trauma workflow
›MRI after stabilization for persistent deficits
CT
›Primary advanced imaging in trauma
›CT pelvis with multiplanar reconstructions
›Posterior ring and sacral ala detail
›Foraminal and canal involvement assessment
›Indications despite normal radiographs
›Focal sacral tenderness with high-energy mechanism
›Inability to mobilize with persistent pain
›Surgical planning value
›Displacement quantification
›Canal compromise degree
›Sacroiliac joint extension
›Associated injury evaluation
›Pelvic hematoma
›Acetabular involvement
07Disposition/dispo27
Discharge criteria
›Low-risk outpatient pathway
›Hemodynamic stability
›No shock indicators
›No transfusion requirement
›Neurologic stability
›No new weakness
›Normal perianal sensation
›Mobility and pain control
›Ambulation with assistive device if needed
›Oral analgesia adequate
Admission and transfer criteria
›Admission indications
›Uncontrolled pain preventing mobilization
›Inadequate outpatient function
›Need for inpatient physiotherapy
›Neurologic deficit
›Progressive symptoms
›Suspected cauda equina
›High-energy pelvic trauma
›Polytrauma observation
›Need for serial exams
›Transfer or urgent specialty involvement
›Spine or orthopedic trauma consultation triggers
›Displaced sacral fracture
›Denis zone III involvement
›Trauma center criteria
›Pelvic ring instability
›Hemodynamic instability or transfusion need
08Treatment/t81
Immediate life-saving interventions
›Resuscitation and hemorrhage control
›Pelvic stabilization when ring injury suspected
›Pelvic binder over greater trochanters
›Minimize logrolling and pelvic manipulation
›Massive hemorrhage pathway when indicated
›Balanced transfusion strategy
›Interventional radiology for arterial bleeding when available
›Neurologic emergency escalation
›If cauda equina concern, emergent spine surgery consultation
›Bladder scan and catheterization for retention
›MRI priority after stabilization
Immobilization and Splinting
›Activity modification and positioning
›Weight-bearing status
›As tolerated for nondisplaced stable fractures
›Protected weight-bearing for painful insufficiency fractures
›Sitting pressure reduction
›Donut or wedge cushion for coccygeal pain
›Side-lying rest during peak pain
›Mobility aids
›Assist devices
›Walker for frailty or severe pain
›Crutches for younger ambulatory patients
›Fall prevention
›Home safety planning
›Early physiotherapy referral when available
Reduction
›Coccyx dislocation reduction considerations
›Indications
›Severe deformity with refractory pain
›Failure of conservative measures with clear dislocation
›Contraindications and caution triggers
›Open perineal wound
›Suspected pelvic ring instability
›Analgesia and anesthesia options
›Non-opioid baseline
›Acetaminophen 1000 mg PO every 6 hours
›Ibuprofen 400 mg PO every 6 to 8 hours with food
›Opioid rescue when needed
›Hydromorphone 1 to 2 mg PO every 4 to 6 hours as needed
›Oxycodone 5 mg PO every 4 to 6 hours as needed
›Procedural sedation if required
›Monitoring requirements
›Continuous pulse oximetry
›Continuous ECG
›Capnography when available
›Medication options
›Ketamine IV 1 mg/kg
›Additional 0.25 to 0.5 mg/kg IV as needed
›Emergence mitigation with quiet environment
›Propofol IV 1 mg/kg
›Titration 0.5 mg/kg every 1 to 3 minutes
›Hypotension and apnea readiness
›Reduction technique principles
›Gentle sustained manipulation with adequate analgesia
›Avoid repeated forceful attempts
›Immediate symptom reassessment
›Post-reduction requirements
›Neuro exam repeat
›Lateral radiograph confirmation when feasible
Open fracture medications and timing
›Antibiotics and tetanus
›Timing principle
›IV antibiotics as early as possible when open fracture suspected
›Do not delay for imaging when wound clearly open
›Antibiotic selection examples
›Cefazolin 2 g IV every 8 hours
›If severe beta-lactam allergy, clindamycin 900 mg IV every 8 hours
›Heavily contaminated wounds
›Add gram-negative coverage per local protocol
›Early operative washout planning
›Tetanus prophylaxis
›Tdap booster if not up to date
›Tetanus immune globulin if unknown or incomplete immunization and dirty wound
DVT prophylaxis when relevant
›Risk-based prophylaxis
›Elevated risk scenarios
›Pelvic ring injury
›Prolonged immobility
›Pharmacologic options when not contraindicated
›Enoxaparin 40 mg subcutaneous daily
›Dose adjustment for renal impairment per local protocol
›Mechanical options
›Intermittent pneumatic compression
›Early mobilization emphasis
09Special Populations/sp28
Pregnancy
›Imaging and analgesia considerations
›Radiation minimization
›CT when needed for maternal stabilization
›Shielding when feasible without compromising image quality
›Medication safety
›Acetaminophen preferred baseline analgesic
›NSAID avoidance in later pregnancy per obstetric guidance
›Obstetric coordination
›Fetal monitoring when viable gestation and significant trauma
›Rh immune globulin when indicated
Geriatric
›Insufficiency fracture pathway
›High suspicion despite normal radiographs
›Early CT or MRI consideration
›Osteoporosis evaluation and treatment referral
›Pain and delirium risk mitigation
›Opioid minimization strategies
›Bowel regimen initiation when opioids used
›Disposition threshold
›Admission for mobility failure
›Inpatient physiotherapy and discharge planning
›Social supports assessment
Pediatrics
›Pediatric coccyx and sacral injury nuances
›Low incidence of true fractures
›Contusion and soft tissue pain common
›Imaging reserved for concerning mechanism or neuro symptoms
›Safeguarding considerations
›Non-accidental trauma consideration when history inconsistent
›Multidisciplinary involvement when indicated
10Background/b39
Epidemiology
›Population patterns
›Sacral fractures often associated with pelvic ring injury in high-energy trauma
›Higher risk of hemorrhage with unstable pelvic patterns
›Higher risk of neurologic injury with central canal involvement
›Sacral insufficiency fractures in older adults
›Osteoporosis association
›Often occult on radiographs
›Coccyx injury characteristics
›Coccydynia commonly post-fall onto buttocks
›Imaging frequently normal
›Management primarily conservative
Pathophysiology
›Mechanism to pattern mapping
›Axial load
›Vertical sacral fractures
›Posterior ring instability potential
›Direct impact
›Coccyx fracture or dislocation
›Local periosteal pain generator
›Neurologic injury mechanisms
›Foraminal involvement
›Nerve root irritation
›Radicular pain patterns
›Canal involvement
›Cauda equina compression risk
›Bladder and bowel dysfunction risk
Therapeutic Considerations
›Nonoperative management rationale
›Stable nondisplaced fractures
›Pain control and mobilization as tolerated
›Avoid prolonged bedrest when possible
›Coccyx injury management
›Cushioning reduces focal pressure
›Stool softeners reduce pain with defecation
›Operative or urgent specialty rationale
›Displaced sacral fractures
›Stability restoration for mobilization
›Reduction of neurologic compromise risk
›Progressive neurologic deficits
›Decompression and stabilization considerations
›Time sensitivity in cauda equina pathways
11Patient Discharge Instructions/pdi33
Copy discharge instructions
›Home care and activity
›Relative rest
›Avoid prolonged sitting on hard surfaces
›Gradual return to activity as pain allows
›Cushioning
›Donut or wedge cushion for sitting
›Side-lying rest breaks
›Mobility
›Weight-bearing as tolerated unless told otherwise
›Use walker or crutches if needed for safety
›Pain plan
›Acetaminophen 1000 mg PO every 6 hours as needed
›Ibuprofen 400 mg PO every 6 to 8 hours as needed with food
›If opioid prescribed
›No driving or alcohol
›Constipation prevention plan
›Bowel care
›Polyethylene glycol 17 g PO daily while on opioids
›Senna 8.6 mg 1 to 2 tablets PO at bedtime while on opioids
›Return to emergency criteria
›New weakness in legs
›Numbness around groin or anus
›Trouble starting urination or inability to urinate
›New bowel incontinence
›Increasing severe pain not controlled with medication
›Fever or wound drainage if skin break present
›Follow-up plan
›Stable coccyx injury
›Primary care or sports medicine follow-up in 1 to 2 weeks if persistent pain
›Consider physiotherapy if ongoing symptoms
›Sacral fracture
›Orthopedics or spine follow-up in 1 to 2 weeks based on stability and imaging
›Earlier follow-up if neurologic symptoms present
12References/r9
Guidelines and core references
›Trauma and resuscitation standards
›ATLS principles for pelvic trauma evaluation and hemorrhage management
›Pelvic binder use in suspected unstable pelvic ring injuries
›Orthopedic and spine references
›Denis sacral fracture classification framework
›AO Spine sacral classification framework
›Procedural sedation references
›ACEP procedural sedation clinical policy evidence levels for ED sedation
›Monitoring standards including capnography when available
Evidence & Review
Reviewed by SymptomDx Medical Team·Last reviewed
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