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Both Column Acetabular Fractures

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Both Column Acetabular Fractures

Comprehensive guide to both column acetabular fractures including Letournel classification, the pathognomonic spur sign, surgical approaches, and fixation strategies

complete
Updated: 2024-12-16
High Yield Overview

Both Column Acetabular Fractures

Complete acetabular dissociation from axial skeleton - the 'floating acetabulum'

20-25% of acetabular fracturesIncidence
High-energy axial loadMechanism
Spur sign on obturator obliqueKey sign
NO articular fragment attached to axial skeletonUnique feature

Letournel Classification - Associated Pattern

Both Column
PatternBOTH anterior and posterior columns fractured with NO articular segment attached to intact ilium
Treatment
Key Distinction
PatternDiffers from transverse in that NO part of dome remains attached to axial skeleton
Treatment

Critical Must-Knows

  • SPUR SIGN is PATHOGNOMONIC - intact ilium above detached columns
  • Entire articular surface is FLOATING (not attached to spine)
  • Most common associated pattern in Letournel classification
  • Secondary congruence may allow conservative treatment in elderly
  • Young patients with displaced fractures need ORIF

Examiner's Pearls

  • "
    Spur sign = both column (on obturator oblique view)
  • "
    Distinguishing from transverse: transverse maintains some dome attachment
  • "
    Iliopectineal AND ilioischial lines both disrupted
  • "
    Secondary congruence: femoral head pushes fragments into alignment
  • "
    Combined approaches often needed (ilioinguinal + Kocher-Langenbeck)

Exam Warning

The Pathognomonic Sign

Spur Sign (Obturator Oblique): Represents intact superior ilium above the floating acetabulum. The key diagnostic feature.

The 'Floating' Concept

Total Dissociation: NO part of the articular surface remains attached to the axial skeleton.

Distinction from Transverse

Transverse: Roof remains attached to ilium. Both Column: Roof is detached (floating).

Radiographic Lines

Double Trouble: Both iliopectineal (anterior) AND ilioischial (posterior) lines are disrupted.

Both Column Acetabular Fractures: Quick Decision Guide

AssessmentFindingAction
Spur sign presentPathognomonic for both columnCT scan for surgical planning
Secondary congruenceFemoral head reduces fragmentsConsider non-operative in elderly
No secondary congruenceDisplaced fragments, incongruentORIF indicated
Young active patientAny displacement beyond 2mmSurgical fixation required
Hip joint stabilityFemoral head centered under roofMay tolerate some displacement
Mnemonic

BOTHBOTH - Both Column Key Features

B
Both columns completely
fractured
O
Obturator oblique shows
the SPUR SIGN
T
Total dissociation from
axial skeleton
H
Hip articulates with
floating segment

Memory Hook:BOTH columns fractured with NO attachment to spine - look for the SPUR sign

Mnemonic

SPURSPUR - The Pathognomonic Sign

S
Superior ilium
remains intact
P
Projection seen on
obturator oblique
U
Unattached acetabulum
below the spur
R
Reliably indicates
both column pattern

Memory Hook:The SPUR sign on obturator oblique confirms both column - intact ilium above floating acetabulum

Mnemonic

FLOATFLOAT - Floating Acetabulum Concept

F
Free from
axial skeleton
L
Lines disrupted
iliopectineal AND ilioischial
O
Obturator view
shows spur sign
A
Articular surface
completely detached
T
Total column
involvement required

Memory Hook:The entire acetabulum FLOATs free - no attachment to spine in both column fractures

Overview and Epidemiology

Introduction

Both column acetabular fractures are the most common associated pattern in the Letournel classification, representing 20-25% of all acetabular fractures. The defining characteristic is that both the anterior and posterior columns are completely fractured, with no portion of the articular surface remaining attached to the intact ilium above.

This creates a "floating acetabulum" where the entire articular segment is dissociated from the axial skeleton. The intact superior ilium remains attached to the sacrum, but the entire acetabulum floats free below.

Obturator oblique X-ray and 3D CT showing pathognomonic spur sign in both column acetabular fracture
Click to expand
The Spur Sign - pathognomonic for both column acetabular fracture. (Left) Obturator oblique radiograph and (Right) 3D CT reconstruction showing the intact superior ilium (arrows) projecting above the medially displaced floating acetabular columns. This sign confirms complete dissociation of the articular surface from the axial skeleton.Credit: Giordano et al., J Clin Orthop Trauma 2020, PMC7656469, CC BY 4.0

Key Concept: The Floating Acetabulum

What Makes Both Column Unique:

  • Both anterior AND posterior columns fractured
  • Fracture lines extend ABOVE the dome (roof)
  • No articular fragment attached to axial skeleton
  • Entire weight-bearing surface is "floating"
  • Intact ilium forms the "spur" sign

Contrast with Transverse:

  • Transverse: Some dome remains attached to ilium above
  • Both column: NO dome attachment to axial skeleton

Epidemiology

Incidence:

  • 20-25% of all acetabular fractures
  • Most common associated pattern
  • Complex injury requiring expert management

Mechanism:

  • High-energy trauma (MVA, falls)
  • Axial load through femoral head
  • Force transmitted to both columns
  • Often associated with dashboard injuries

Demographics:

  • Young patients: High-energy trauma
  • Elderly: Lower energy (osteoporotic bone)
  • Male predominance in young
  • Bimodal age distribution

Anatomy and Biomechanics

Acetabular Anatomy

Understanding the column concept is essential for classifying acetabular fractures.

The Two-Column Model

Anterior Column (Iliopubic):

  • Extends from iliac crest to symphysis
  • Includes: Iliac wing anterior portion, anterior wall, pubic ramus
  • Forms anterior half of acetabular dome
  • Represented by iliopectineal line on X-ray

Posterior Column (Ilioischial):

  • Extends from greater sciatic notch to ischial tuberosity
  • Includes: Greater sciatic notch, posterior wall, ischial tuberosity
  • Forms posterior half of acetabular dome
  • Represented by ilioischial line on X-ray

Radiographic Lines

Iliopectineal Line:

  • Runs from iliac crest to pubis
  • Represents anterior column
  • Disrupted in anterior column fractures

Ilioischial Line:

  • Runs from greater sciatic notch to ischium
  • Represents posterior column
  • Disrupted in posterior column fractures

Both Column Fracture:

  • BOTH iliopectineal AND ilioischial lines disrupted
  • Plus SPUR SIGN
3D pelvic model diagrams showing Y-shaped both column acetabular fracture patterns
Click to expand
Both column fracture patterns (Y-shaped types). (A) Low anterior column - vertical fracture line exits between ASIS and iliac tuberosity. (B) High anterior column (H-shaped) - fracture line exits at iliac crest with secondary line. (C) High anterior column (X-shaped) - fracture extends into SI joint. Pink lines indicate fracture patterns.Credit: Giordano et al., J Clin Orthop Trauma 2020, PMC7656469, CC BY 4.0

Classification Systems

Elementary Patterns (5):

Anterior wall involves isolated anterior wall fracture. Anterior column extends from iliac crest to pubis. Posterior wall is the most common elementary pattern. Posterior column involves the ilioischial line. Transverse fracture divides acetabulum into superior and inferior halves.

Associated Patterns (5):

T-shaped combines transverse with vertical component. Posterior column plus posterior wall is a common combination. Transverse plus posterior wall involves additional instability. Anterior column/wall plus posterior hemitransverse is complex associated pattern. Both column (this topic) is the most common associated pattern at 20-25%.

Diagnostic Criteria:

Both anterior and posterior columns are completely fractured. No articular segment remains attached to axial skeleton. Spur sign is pathognomonic and present on obturator oblique view. Both iliopectineal and ilioischial lines are disrupted.

Subtypes:

High both column involves fracture exiting through iliac crest. Low both column involves fracture exiting through sciatic notch. With posterior wall component indicates additional instability requiring assessment.

Definition:

Secondary congruence occurs when femoral head pushes detached acetabular fragments into acceptable alignment during weight-bearing. This phenomenon is unique to both column fractures because entire acetabulum is floating.

Clinical Significance:

Presence of secondary congruence may allow non-operative treatment in selected elderly patients. Femoral head centered under roof with minimal step indicates acceptable alignment. CT assessment is required to evaluate congruence.

Classification Pearl

Both column fracture is distinguished from transverse by the spur sign and complete dissociation. In transverse fractures, some dome remains attached to axial skeleton above the fracture. In both column, NO articular surface has any attachment to the spine - the entire acetabulum floats.

Clinical Assessment

History and Mechanism

High-Energy Mechanisms:

  • Motor vehicle accident (dashboard injury)
  • Motorcycle accident
  • Fall from height
  • Pedestrian struck
  • Sports (skiing, equestrian)

Force Transmission:

  • Axial load through femoral head
  • Position of hip determines fracture pattern
  • Both columns receive force

Physical Examination

General Assessment:

  • Polytrauma common - ATLS approach
  • Associated pelvic ring injury possible
  • Ipsilateral lower extremity injuries

Hip-Specific:

  • Shortened, externally rotated limb (if dislocated)
  • Pain with hip motion
  • Unable to bear weight
  • Tenderness over hip/pelvis

Neurovascular Assessment:

Sciatic nerve injury occurs in 10-15% of acetabular fractures, especially posterior patterns. Document detailed L5 (great toe extension) and S1 (ankle plantarflexion) function BEFORE any intervention. Peroneal division is more vulnerable - foot drop is the classic presentation.

Motor:

  • Hip flexion (L1-2)
  • Knee extension (L3-4)
  • Ankle dorsiflexion (L4-5)
  • Great toe extension (L5) - most vulnerable
  • Ankle plantarflexion (S1)

Sensory:

  • Lateral thigh (L2)
  • Medial leg (L4)
  • Dorsum foot (L5)
  • Lateral foot (S1)

Associated Injuries

Common Associations:

  • Femoral head fractures (Pipkin)
  • Femoral neck fractures
  • Hip dislocation
  • Ipsilateral knee injuries (dashboard)
  • Contralateral injuries

Investigations

Imaging Protocol

Plain Radiography (Judet Views)

Standard Series:

  1. AP pelvis
  2. Obturator oblique (45 degrees)
  3. Iliac oblique (45 degrees)

AP Pelvis:

  • Both iliopectineal AND ilioischial lines disrupted
  • Roof involvement
  • Femoral head position

Obturator Oblique (KEY VIEW):

  • SPUR SIGN visible - pathognomonic
  • Anterior column profile
  • Posterior wall en face

Iliac Oblique:

  • Posterior column profile
  • Anterior wall en face
  • Greater sciatic notch

CT Imaging

Essential for Surgical Planning:

  • 2mm axial cuts through acetabulum
  • 3D reconstructions extremely helpful
  • Coronal and sagittal reformats
3D CT reconstruction showing posterior aspect of both column acetabular fracture with associated posterior wall involvement
Click to expand
3D CT reconstruction demonstrating the posterior aspect of a both column fracture with associated posterior wall fragment (white arrowheads). Posterior wall involvement occurs in nearly 40% of both column fractures and is typically a large, noncomminuted fragment created by a pull-type mechanism.Credit: Giordano V et al., J Clin Orthop Trauma 2020

Key Findings on CT:

  • Fracture extent in both columns
  • Articular surface congruence
  • Femoral head integrity
  • Intra-articular fragments
  • Marginal impaction

CT with 3D Reconstruction:

  • Demonstrates both column disruption
  • Shows floating acetabulum concept
  • Excellent for surgical planning
  • Communication with patient/team

Secondary Congruence Assessment

Definition:

  • Femoral head pushes fractured acetabular fragments into alignment
  • Creates acceptable articular surface despite fracture
  • May allow conservative treatment in select cases

CT Criteria:

  • Roof arc measurements
  • Articular step-off
  • Gap assessment
  • Overall congruence
Fracture mapping of both column acetabular fractures showing Y-shaped pattern corridors
Click to expand
Fracture line mapping in both column acetabular fractures. (A) Hemipelvis anatomy showing relevant zones. (B) Superimposed fracture lines from 71 cases demonstrating common patterns. (C) Y-shaped 'corridors' where 92% of major fracture lines occur, highlighting the consistency of both column fracture patterns.Credit: Yang Y et al., BMC Musculoskelet Disord 2019

Management

Indications:

Secondary congruence present with femoral head molding fragments into alignment. Elderly low-demand patients with acceptable articular surface. Medical comorbidities precluding major surgery. Roof arc measurements greater than 45 degrees in all planes. Minimal displacement with acceptable articular congruence.

Secondary Congruence Concept:

Femoral head acts as mold and pushes fragments into alignment. Creates functional weight-bearing surface despite fracture. More common in elderly patients with comminuted fractures. Unique to both column fractures where entire acetabulum floats.

Protocol:

Skeletal traction initially for 2-4 weeks followed by progressive mobilization. Weight-bearing restrictions maintained for 6-12 weeks. Serial radiographs to monitor alignment. Conversion to surgery if alignment lost.

Indications:

Displaced fractures in young active patients. Loss of secondary congruence on CT assessment. Roof arc less than 45 degrees. Articular step-off greater than 2mm. Associated femoral head injury requiring open treatment. Failed conservative treatment with loss of alignment.

Timing:

Surgery ideally within 3-7 days after injury to allow swelling to settle. Must be performed within 14-21 days before callus formation. Beyond 3 weeks reduction becomes significantly more difficult. May need traction while awaiting surgery.

Approach Selection:

Based on which column predominates and fracture configuration. Anterior column predominant uses ilioinguinal approach. Posterior column predominant uses Kocher-Langenbeck. Combined approaches frequently required for both column pattern.

📊 Management Algorithm
Both Column Acetabular Fracture Management Algorithm
Click to expand
Management Algorithm: Decision-making based on secondary congruence and patient factors. Note the pathognomonic spur sign as a key diagnostic entry point.Credit: OrthoVellum

Step 1: Assess Secondary Congruence

CT scan to evaluate if femoral head has molded fragments into alignment. If present with acceptable roof, consider conservative in elderly.

Step 2: Evaluate Patient Factors

Young active patient generally requires anatomic reduction. Elderly low-demand patient may tolerate some incongruity. Medical fitness for major surgery must be assessed.

Step 3: Plan Surgical Approach

Determine which column is more displaced for primary approach. Plan combined approach if both significantly displaced. Consider timing and staging based on patient condition.

Management Decision

The key to both column management is secondary congruence assessment. If the femoral head has molded the floating acetabulum into acceptable alignment, conservative treatment may succeed in elderly patients. Young patients with displacement need ORIF regardless of secondary congruence.

Surgical Technique

Access Provided:

Anterior column from iliac crest to pubic symphysis. Quadrilateral surface and inner table of ilium. Superior pubic ramus and pelvic brim.

Indications:

Anterior column-predominant both column fractures. High both column variants exiting through iliac crest.

Key Structures at Risk:

External iliac vessels in middle window. Femoral nerve lateral to vessels. Lateral femoral cutaneous nerve over ASIS. Corona mortis (aberrant obturator artery) in 15-30% of cases.

Technique Highlights:

Three windows created (lateral, middle, medial). Lateral femoral cutaneous nerve identified and protected. Iliac vessels and femoral nerve protected in middle window.

Access Provided:

Posterior column from greater sciatic notch to ischial tuberosity. Posterior wall and retroacetabular surface. Greater and lesser sciatic notches.

Indications:

Posterior column-predominant fractures. Associated posterior wall component. Low both column variants exiting through sciatic notch.

Key Structures at Risk:

Sciatic nerve (identified and protected throughout). Superior gluteal artery at sciatic notch. Inferior gluteal artery and nerve. Medial femoral circumflex artery (avoid excessive retraction).

Technique Highlights:

Lateral decubitus or prone position. Interval between gluteus maximus and medius. Sciatic nerve protected with knee flexed. Short external rotators released for access.

When Required:

Most both column fractures need visualization of both columns. Displacement significant in both anterior and posterior.

Options:

Simultaneous combined approach with patient lateral and anterior approach through same incision or separate. Sequential staged approach with flip from prone to supine.

Modified Stoppa Addition:

Better quadrilateral plate access through anterior midline approach. Can be combined with ilioinguinal windows. Useful for medial displacement of quadrilateral surface.

Reduction Techniques:

Farabeuf clamps and pointed reduction forceps for anterior column. Matta clamp and Schanz pin joystick for posterior column. Ball spike pusher through ilioinguinal windows.

Anterior Column Fixation:

3.5mm pelvic reconstruction plates contoured along iliopectineal line. Infrapectineal plate for quadrilateral surface if needed. Column screws from anterior to posterior.

Posterior Column Fixation:

Standard 3.5 mm reconstruction plates along posterior column. Spring plates for comminuted posterior wall. Lag screws for large articular fragments.

Post-operative radiographs and 3D CT after both column acetabular fracture fixation
Click to expand
Post-operative imaging following ORIF of both column acetabular fracture. (A-E) Immediate post-operative AP pelvis, outlet, obturator oblique, inlet, and iliac oblique radiographs showing anatomic reduction. (F-J) 3D CT at 3-year follow-up demonstrating no osteoarthritis, heterotopic ossification, or avascular necrosis of the femoral head.Credit: Giordano V et al., J Clin Orthop Trauma 2020

Neurovascular Structures

Anterior approach: Corona mortis crosses surgical field in 15-30% - ligate before division. External iliac vessels protected in middle window. Posterior approach: Sciatic nerve must be identified and protected throughout. Avoid excessive retraction which damages medial femoral circumflex artery.

Complications

Early Complications

Nerve Injury:

  • Sciatic nerve (10-15%)
  • Peroneal division most vulnerable
  • Document preoperatively

Vascular Injury:

  • Corona mortis (ilioinguinal approach)
  • Superior gluteal artery (posterior approach)
  • External iliac vessels

Thromboembolic:

  • Very high DVT risk
  • PE significant concern
  • Prophylaxis essential

Infection:

  • Surgical site infection
  • Higher with extensive approaches
  • Proper skin handling important

Late Complications

Post-traumatic Arthritis:

  • Most common long-term complication
  • Related to reduction quality
  • Greater than 3mm step-off strongly predictive
  • May need THR

Heterotopic Ossification:

  • Common after extensive approaches
  • Prophylaxis: Indomethacin or radiation
  • May limit ROM

AVN of Femoral Head:

  • Associated posterior dislocation
  • Delay in reduction
  • Poor prognosis

Postoperative Care

First 48-72 Hours:

Monitor for compartment syndrome and neurovascular status. DVT prophylaxis is mandatory given high risk. Wound care with drain removal at 24-48 hours. Pain management and early mobilization as tolerated.

Weight-Bearing:

Touch weight-bearing initially with crutches or frame. Progression based on fracture pattern and fixation stability. Protected weight-bearing for 8-12 weeks typically.

Week 1-6:

Range of motion exercises begin immediately. Hip flexion active and passive within comfort. Focus on quad and hip abductor strengthening. DVT prophylaxis continues for 4-6 weeks minimum.

Week 6-12:

Progressive weight-bearing based on radiographic healing. Pool therapy if available. Gait training with progression from walker to cane. Continued strengthening program.

Radiographic Monitoring:

X-rays at 2, 6, and 12 weeks post-operatively. CT scan if concern about reduction or healing. Look for loss of reduction or hardware failure.

Long-Term:

Annual review for first 2 years. Monitor for post-traumatic arthritis. May need THR if significant arthritis develops.

Outcomes/Prognosis

Surgical Outcomes

Anatomic reduction (less than 1mm) achieves 80% good to excellent results. Reduction quality is the strongest predictor of outcome. Combined approaches allow adequate access for most patterns.

Risk Factors for Arthritis

Articular step-off greater than 3mm strongly predicts arthritis. Associated femoral head injury worsens prognosis. Delay in surgery beyond 3 weeks compromises reduction.

Outcome by Reduction Quality

ReductionStep-offGood/Excellent Outcome
AnatomicLess than 1mm80-90%
Satisfactory1-3mm60-70%
PoorGreater than 3mmLess than 30%

Evidence Base

Spur Sign Pathognomonic Value

Expert Opinion
Letournel E, Judet R • Fractures of the Acetabulum (1993)
Key Findings:
  • The spur sign on obturator oblique radiograph is pathognomonic for both column acetabular fractures. It represents intact ilium above the completely dissociated acetabular columns.
Clinical Implication: If you see the spur sign, you can confidently diagnose both column fracture. It is THE distinguishing feature from transverse fractures.

Secondary Congruence Outcomes

Level IV
Matta JM et al. • Clinical Orthopaedics (1986)
Key Findings:
  • Patients with secondary congruence (femoral head molding fractured acetabulum into acceptable alignment) can achieve good outcomes with conservative treatment, particularly in elderly patients.
Clinical Implication: Assess for secondary congruence on CT. If present, especially in elderly/low-demand patients, conservative treatment may be appropriate.

Combined Surgical Approaches

Level IV
Matta JM • Journal of Bone and Joint Surgery (1996)
Key Findings:
  • Combined ilioinguinal and Kocher-Langenbeck approaches for both column fractures provide adequate access for anatomic reduction. Sequential or simultaneous approaches based on fracture pattern.
Clinical Implication: Both column fractures often require combined approaches. Plan based on which column is more displaced and accessible.

Timing of Surgery

Level III
Mears DC, Velyvis JH • Journal of Orthopaedic Trauma (2002)
Key Findings:
  • Surgical treatment within 14 days of injury associated with better reduction quality and clinical outcomes. Beyond 21 days, reduction becomes significantly more difficult due to callus formation.
Clinical Implication: Plan surgical fixation within 2 weeks if possible. Delayed surgery beyond 3 weeks significantly compromises reduction.

Radiographic Reduction and Outcomes

Level IV
Matta JM • Clinical Orthopaedics (1996)
Key Findings:
  • Anatomic reduction (less than 1mm displacement) achieved the best clinical outcomes. Good reduction (1-3mm) had acceptable outcomes. Poor reduction (greater than 3mm) strongly predicted post-traumatic arthritis.
Clinical Implication: Strive for anatomic reduction. Residual displacement greater than 3mm is associated with poor outcomes and arthritis.

Viva Scenarios

Exam Viva Scenarios

Practice these scenarios to excel in your viva examination

VIVA SCENARIOChallenging

Both Column Fracture Management

EXAMINER

"A 35-year-old woman is in a high-speed MVA. X-rays show disruption of both iliopectineal and ilioischial lines, with a spur sign on obturator oblique. CT confirms both column acetabular fracture with 5mm articular step-off. Describe your management approach."

EXCEPTIONAL ANSWER

Recognition: Both column acetabular fracture confirmed by spur sign and disruption of both radiographic lines. Significant displacement (5mm step-off).

Initial Management:

  • ATLS approach - exclude polytrauma
  • Document sciatic nerve function (L5, S1)
  • Skeletal traction (distal femur or proximal tibia)
  • Adequate analgesia
  • DVT prophylaxis

Imaging Assessment:

  • Judet views confirm both column pattern
  • Spur sign pathognomonic
  • CT with 3D reconstruction for surgical planning
  • Greater than 5mm step-off exceeds acceptable threshold
  • No secondary congruence present

Surgical Indication:

  • Young patient (35 years) with high demands
  • Displaced fracture (greater than 2mm step-off)
  • No secondary congruence
  • Clear indication for ORIF

Surgical Planning:

  • Timing: Within 2 weeks ideally
  • Approach: Likely combined (ilioinguinal + Kocher-Langenbeck)
  • Evaluate which column more displaced to determine primary approach
  • May stage if medically needed

Goals:

  • Anatomic reduction (less than 2mm, ideally less than 1mm)
  • Stable fixation
  • Restore articular congruence
  • Early mobilization
KEY POINTS TO SCORE
Spur sign confirms both column fracture
Both iliopectineal and ilioischial lines disrupted
Young patient needs ORIF
Combined approaches often required
5mm step-off exceeds threshold
COMMON TRAPS
✗Missing spur sign on obturator oblique
✗Not documenting sciatic nerve pre-op
✗Delaying surgery beyond 2 weeks
✗Inadequate approach for both columns
LIKELY FOLLOW-UPS
"What surgical approach would you use?"
"What if secondary congruence was present?"
VIVA SCENARIOStandard

The Spur Sign

EXAMINER

"Explain the spur sign and how it distinguishes both column fractures from transverse fractures."

EXCEPTIONAL ANSWER

The Spur Sign:

  • Seen on OBTURATOR OBLIQUE radiograph
  • Represents intact superior ilium
  • Located above the completely detached columns
  • Pathognomonic for both column fractures

Why It Occurs:

  • In both column fractures, both anterior AND posterior columns separate from axial skeleton
  • The intact ilium above remains attached to sacrum
  • This creates a "spur" of bone projecting into the defect
  • Best seen on obturator oblique (45-degree rotation)

Distinction from Transverse:

Transverse Fracture:

  • Single fracture line across acetabulum
  • Divides acetabulum into superior and inferior portions
  • SUPERIOR (roof) portion remains attached to ilium
  • No spur sign - roof attached above fracture

Both Column Fracture:

  • Both columns completely fractured
  • Fracture lines extend ABOVE the dome
  • NO articular segment attached to ilium
  • Spur sign PRESENT - ilium above floating columns

Clinical Importance:

  • Both column may develop secondary congruence (conservative option)
  • Transverse usually requires surgery to restore roof congruence
  • Surgical approach differs based on pattern
KEY POINTS TO SCORE
Spur sign pathognomonic for both column
Seen on obturator oblique view
Transverse has dome attached to ilium
Both column has NO articular attachment
Best seen at 45-degree rotation
COMMON TRAPS
✗Missing spur sign on obturator oblique
✗Confusing with transverse fracture
✗Not understanding the floating acetabulum concept
LIKELY FOLLOW-UPS
"What view shows the spur sign best?"
"What is secondary congruence?"
VIVA SCENARIOChallenging

Secondary Congruence Management

EXAMINER

"An 80-year-old woman with multiple comorbidities has a both column acetabular fracture from a low-energy fall. CT shows secondary congruence with acceptable articular alignment. How would you manage this patient?"

EXCEPTIONAL ANSWER

Assessment:

  • Both column fracture confirmed
  • Secondary congruence PRESENT - key finding
  • Low-energy mechanism in elderly
  • Multiple medical comorbidities

Secondary Congruence Concept:

  • Femoral head acts as template
  • Pushes fractured acetabular segments into acceptable position
  • Creates congruent weight-bearing surface
  • Despite lack of fixation, acceptable function possible

Conservative Management Indicated:

  • Elderly patient with limited demands
  • Multiple comorbidities increase surgical risk
  • Secondary congruence provides acceptable alignment
  • Low-energy suggests osteoporotic bone (poor fixation)

Protocol:

  • Initial skeletal traction (2-3 weeks)
  • Monitor for maintaining congruence
  • Progress to chair sitting
  • Non-weight bearing with walker (6-8 weeks)
  • Progressive weight bearing by 10-12 weeks
  • Serial radiographs to monitor alignment

Monitoring:

  • Weekly radiographs initially
  • Watch for loss of congruence (would indicate surgery)
  • DVT prophylaxis throughout
  • Pressure area care
  • Accept some late arthritis (may need THR in future)

Expected Outcome:

  • Reasonable function for low-demand patient
  • May develop post-traumatic arthritis over years
  • THR remains future option if needed
KEY POINTS TO SCORE
Secondary congruence allows conservative treatment
Elderly with comorbidities may avoid surgery
Femoral head molds fragments into position
THR remains backup option
Weekly radiographs to monitor
COMMON TRAPS
✗Operating on elderly with good secondary congruence
✗Not monitoring for loss of congruence
✗Forgetting DVT prophylaxis
✗Pressure area neglect
LIKELY FOLLOW-UPS
"What if congruence is lost during monitoring?"
"When would you still operate on an elderly patient?"

MCQ Practice Points

Pathognomonic Sign Question

Q: Which radiographic sign is pathognomonic for both column acetabular fractures?

A: SPUR sign on obturator oblique view. The spur represents intact superior ilium above the completely detached anterior and posterior columns. This sign confirms that NO articular surface remains attached to the axial skeleton.

Differentiation Question

Q: How do you differentiate both column fracture from transverse fracture?

A: Spur sign is present only in both column fractures. In transverse fractures, some dome remains attached to the axial skeleton above the fracture line. In both column, NO articular surface has any attachment to the spine - the entire acetabulum floats.

Radiographic Lines Question

Q: Which radiographic lines are disrupted in both column acetabular fractures?

A: BOTH iliopectineal AND ilioischial lines are disrupted. Iliopectineal represents anterior column, ilioischial represents posterior column. Disruption of both confirms involvement of both columns.

Secondary Congruence Question

Q: What is secondary congruence and when does it allow conservative treatment?

A: Secondary congruence occurs when the femoral head molds the floating acetabular fragments into acceptable alignment. It is unique to both column fractures and may allow conservative treatment in elderly, low-demand patients with acceptable roof arc measurements.

Outcome Predictor Question

Q: What is the most important prognostic factor after acetabular fracture surgery?

A: Reduction quality. Anatomic reduction (less than 1mm step-off) achieves 80-90% good outcomes. Greater than 3mm step-off is strongly predictive of post-traumatic arthritis.

Australian Context

Both column acetabular fractures are typically seen in major trauma centres across Australia following high-energy mechanisms such as motor vehicle accidents. The Australian Orthopaedic Association and major trauma networks have established referral pathways for these complex injuries.

Management follows international evidence-based guidelines with emphasis on early transfer to specialized pelvic and acetabular units. Most Australian states have designated trauma centers with expertise in these complex injuries.

Prophylaxis against heterotopic ossification with indomethacin or radiation follows standard protocols. DVT prophylaxis is mandatory given the high thromboembolic risk associated with pelvic and acetabular trauma.

Long-term follow-up is essential for monitoring development of post-traumatic arthritis, which may eventually require total hip arthroplasty in a proportion of patients regardless of initial treatment quality.

Both Column Acetabular Fractures

High-Yield Exam Summary

Key Features

  • •20-25% of acetabular fractures (most common associated)
  • •NO articular segment attached to axial skeleton
  • •BOTH iliopectineal AND ilioischial lines disrupted
  • •SPUR sign on obturator oblique is pathognomonic

Radiographic Findings

  • •Obturator oblique shows SPUR sign
  • •Both column lines disrupted
  • •CT with 3D for surgical planning
  • •Assess for secondary congruence

Management

  • •Young patient displaced: ORIF (combined approaches)
  • •Elderly with secondary congruence: conservative
  • •Timing: within 2 weeks for best outcomes
  • •Reduction goal: less than 2mm step-off

Surgical Approaches

  • •Ilioinguinal for anterior column
  • •Kocher-Langenbeck for posterior column
  • •Combined approaches often needed
  • •Sciatic nerve injury risk 10-15%

Key Pitfalls

  • •Missing spur sign (only on obturator oblique)
  • •Confusing with transverse (transverse has dome attached)
  • •Not documenting sciatic nerve preoperatively
  • •Delaying surgery beyond 2 weeks
Quick Stats
Reading Time84 min
Related Topics

Anteroposterior Compression (APC) Pelvic Injuries

Lateral Compression Pelvic Injuries

Open Book Pelvic Injuries

Sacral Fractures