High Yield Overview
Pubic Rami Fractures
Fragility Fracture | Assess for Ring Involvement
ElderlyCommon Population
Ring?Key Question
ConservativeMost Treatment
MobilityGoal
Pubic Rami Fracture Types
Isolated (Anterior)
PatternRami only. Ring intact. Usually stable.
TreatmentConservative
With Ring Involvement
PatternAssociated posterior injury (Sacral, SI). Unstable.
TreatmentORIF / Sacroplasty
LC-1
PatternRami + Ipsilateral sacral compression.
TreatmentConservative or ORIF
Critical Must-Knows
- Key Question: Is the posterior ring involved? Isolated rami = Stable. Posterior injury = Consider instability.
- Population: Often elderly with fragility fractures (low-energy). Young with high-energy trauma.
- Imaging: CT Pelvis to assess posterior ring (Sacrum, SI joints).
- Treatment: Isolated rami = Conservative (Analgesia, Mobility). Ring involvement = May need fixation.
- Goal: Early mobilization. Prevent immobility complications.
Examiner's Pearls
- "Pubic rami fractures are common fragility fractures in the elderly.
- "ALWAYS image the posterior ring (CT) - a ring cannot break in one place only.
- "Lateral Compression Type 1 (LC-1) = Rami + Sacral compression. Usually stable.
- "Focus on early mobilization to prevent immobility complications.
Pubic Rami Fracture Pitfalls
Missing Posterior Injury
A Ring Breaks in Two Places. If rami are fractured, LOOK for posterior injury. May be subtle on X-ray.
Immobility
Biggest Risk. Prolonged immobility leads to DVT, PE, Pneumonia, Deconditioning, Death. Mobilize early.
Fragility Fracture
Osteoporosis Workup. Pubic rami fractures in elderly = Osteoporosis. Start treatment.
Associated Injuries
In Young Patients. High-energy rami fractures may have bladder/urethral injury. Check for hematuria.
At a Glance: Isolated vs Ring Involvement
| Feature | Isolated Rami | With Ring (e.g., LC-1) |
|---|---|---|
| Posterior Ring | Intact | Sacral compression / SI injury |
| Stability | Stable | Usually Stable (LC-1) but assess |
| Treatment | Conservative | Conservative or ORIF |
| Imaging | CT to confirm | CT shows sacral fracture |
| Prognosis | Good | May have chronic pain |
Mnemonic
RING = 2Ring Rule
R
Ring
Pelvic ring is a circle
I
If
If broken...
N
Not One
Cannot break in just one place
G
Get CT
CT to find the second break
Memory Hook:A ring breaks in TWO places.
Mnemonic
MOBILEFragility Fracture Protocol
M
Mobilize
Early weight-bearing is key
O
Osteoporosis
Treat osteoporosis
B
Bone Health
Calcium + Vitamin D
I
Independence
Goal is independence
L
Low DVT Risk
DVT prophylaxis
E
Elderly Care
Geriatric/Orthogeriatric input
Memory Hook:MOBILE for fragility rami fractures.
Mnemonic
Rami + SacrumLC-1 Pattern
L
Lateral
Lateral Compression mechanism
C
Compression
Side-impact compresses pelvis
1
One
Type 1 = Most stable LC
R
Rami
Anterior: Pubic rami fractures
S
Sacrum
Posterior: Ipsilateral sacral compression
Memory Hook:LC-1 = Rami + Sacral compression.
Overview and Epidemiology
Definition: Pubic rami fractures involve the superior and/or inferior pubic rami. They may be isolated (ring intact) or associated with posterior ring injury (sacral fracture, SI joint injury).
Epidemiology:
- Elderly Fragility Fractures: Most common presentation. Low-energy fall.
- Young High-Energy: MVA, Fall from height. Often part of major pelvic ring injury.
- Incidence: Very common fragility fracture. Often under-recognized.
Anatomy and Pathophysiology
Anatomy:
- Superior Pubic Ramus: Connects pubic body to acetabulum (forms anterior column).
- Inferior Pubic Ramus: Connects pubic body to ischium.
- Pubic Symphysis: Fibrocartilaginous joint at midline.
Ring Concept:
- The pelvic ring is a closed loop: Sacrum, SI joints, Innominate bones (Ilium, Ischium, Pubis), Symphysis.
- A complete ring cannot break in only one place. If rami are fractured, look posteriorly.
Exception:
- Insufficiency Fractures: Osteoporotic bone can have incomplete or subtle posterior fractures (Sacral insufficiency fractures).
Classification
Simple Classification
- Isolated Rami: Superior and/or Inferior rami only. Posterior ring intact on CT.
- With Ring Involvement: Rami + Sacral fracture (LC-1) or SI injury or Contralateral rami.
CT is essential to determine this.
Clinical Assessment
History:
- Mechanism: Low-energy fall (elderly)? High-energy (young)?
- Pain Location: Groin, anterior pelvis.
- Mobility: Can they walk? Weight-bear?
Physical Examination:
- Tenderness: Pubic rami (groin/anterior pelvis).
- Deformity: Usually none (isolated stable fractures).
- Compression/Distraction: May elicit pain.
- Gait: Antalgic.
- GU Exam: Blood at meatus? Urethral injury in high-energy (especially males).
- PR/PV Exam: Assess for associated injury.
Investigations
Imaging:
- X-ray (AP Pelvis): Shows rami fractures. May miss posterior injury.
- CT Pelvis: Essential. Assess posterior ring (Sacrum, SI joints).
- MRI: If CT negative but high clinical suspicion. For occult sacral insufficiency fractures.
Key Findings:
- Rami Fractures: Usually visible on X-ray.
- Sacral Compression (LC-1): May be subtle on CT. Look for buckling of sacral ala.
- Sacral Insufficiency Fracture: Classic 'H-sign' on MRI (bilateral sacral + transverse fractures).
Management Algorithm
📊 Management Algorithm
Click to expand
Isolated Rami (Ring Intact)
Conservative Management.
- Analgesia: Multimodal. Paracetamol, NSAIDs (caution in elderly), Opioids PRN.
- Early Mobilization: WBAT with walker/frame. Physio input Day 1.
- DVT Prophylaxis: Chemical + Mechanical.
- Osteoporosis: Start treatment (Calcium, Vitamin D, Bisphosphonate/Denosumab).
- Discharge Planning: Home vs Rehabilitation.
Goal: Get them moving. Prevent immobility complications.
Surgical Technique
Sacroplasty for Sacral Insufficiency Fractures
Indications:
- Painful sacral insufficiency fracture
- Failed conservative management (still unable to mobilize)
- No neurological deficit
Technique:
- Position: Prone on radiolucent table
- Guidance: Fluoroscopy or CT-guided
- Access: Trocar needles placed into sacral ala bilaterally
- Cement: PMMA injected into fracture site under live imaging
- Volume: Usually 2-4ml per side
Outcomes:
- Significant pain relief in 80-90%
- Allows earlier mobilization
Reserved for fractures not responding to conservative care.
Complications
Complications
| Complication | Risk Factor | Prevention/Management |
|---|---|---|
| DVT/PE | Immobility | Early mobilization + Prophylaxis |
| Pneumonia | Bed rest | Early mobilization + Resp physio |
| Deconditioning | Bed rest | Early mobilization |
| Pressure Sores | Immobility | Pressure care |
| Chronic Pain | Sacral involvement | Analgesia / Sacroplasty |
| Mortality | Frailty, Immobility | Orthogeriatric care |
Mortality:
- 1-year mortality for elderly pelvic fragility fractures is significant (10-20%).
- Similar to hip fractures.
- Orthogeriatric model of care improves outcomes.
Postoperative Care
Conservative Care:
- Mobilize Day 1.
- Walker/Frame.
- Physio daily.
- Discharge when safe (Home vs Rehab).
Post-Sacroplasty:
- Mobilize same day or next day.
- Weight-bear as tolerated.
- Follow-up X-ray.
Outcomes
- Isolated Rami: Good outcomes if mobilized early.
- With Ring/Sacral: May have chronic pain. Sacroplasty can help.
- Elderly Frailty: High morbidity/mortality from immobility.
Evidence Base
Fragility Pelvic Fractures
Key Findings:
- Proposed classification for fragility pelvic fractures.
- Highlighted posterior ring involvement in many cases.
- Emphasized early mobilization.
Clinical Implication: Always assess posterior ring. Mobilize early.
Limitation: Descriptive
Sacroplasty
Key Findings:
- Reviewed sacroplasty for sacral insufficiency fractures.
- Good pain relief in most patients.
- Allows early mobilization.
Clinical Implication: Consider sacroplasty for painful sacral fractures.
Limitation: Case series
Mortality in Pelvic Fragility Fractures
Key Findings:
- 1-year mortality similar to hip fractures.
- Immobility is key risk factor.
- Early mobilization improves outcomes.
Clinical Implication: Treat with same urgency as hip fractures.
Limitation: Retrospective
LC-1 Stability
Key Findings:
- Most LC-1 fractures are stable.
- Weight-bearing as tolerated is safe.
- Follow-up imaging for displacement.
Clinical Implication: LC-1 can be managed conservatively.
Limitation: Retrospective
Ring Concept
Key Findings:
- Established the principle that a ring breaks in two places.
- If anterior is broken, look posterior.
Clinical Implication: Always image the whole ring.
Limitation: Expert opinion
Viva Scenarios
Exam Viva Scenarios
Practice these scenarios to excel in your viva examination
VIVA SCENARIOStandard
The Elderly Fall
EXAMINER
"What is your assessment and management?"
EXCEPTIONAL ANSWER
**Pubic Rami Fractures - Assess Ring, Mobilize Early.**
1. **Imaging**:
- X-ray shows rami fractures.
- BUT: A ring breaks in two places. Get CT Pelvis.
- Look for sacral compression or SI injury.
2. **If Isolated Rami (Ring Intact)**:
- *Conservative*: Analgesia, Early Mobilization (WBAT with frame).
- *DVT Prophylaxis*.
- *Osteoporosis Treatment*: Start Calcium, Vitamin D, Bisphosphonate.
3. **If LC-1 (Sacral Compression)**:
- Still usually conservative.
- If severe pain limiting mobilization, consider *Sacroplasty*.
4. **Geriatric Input**: Orthogeriatric model. Discharge planning (Home vs Rehab).
5. **Goal**: Get her moving to prevent complications.
KEY POINTS TO SCORE
CT to assess posterior ring
Mobilize early
Treat osteoporosis
Orthogeriatric care
COMMON TRAPS
✗Not imaging posterior ring
✗Keeping patient in bed (increases mortality)
LIKELY FOLLOW-UPS
"What is LC-1?"
"What is Sacroplasty?"
VIVA SCENARIOStandard
The Ring Rule
EXAMINER
"Explain the 'Ring Rule'."
EXCEPTIONAL ANSWER
**A Ring Cannot Break in Only One Place.**
1. **Pelvic Ring**: Sacrum + SI joints + Innominate bones + Symphysis. Forms a closed ring.
2. **Physics**: A rigid ring, if broken, must break in at least two places.
3. **Application**:
- If pubic rami are fractured (anterior ring), there is likely a second injury posteriorly.
- This could be: Sacral fracture (compression or transverse), SI joint injury.
4. **CT Role**:
- X-ray may miss subtle posterior injuries (especially sacral buckling).
- CT defines the full injury pattern.
5. **Implication**:
- Isolated rami (no posterior injury) = Stable.
- Rami + Posterior = May be unstable (assess further).
**Exception**: In osteoporotic bone, insufficiency fractures can be incomplete or subtle.
KEY POINTS TO SCORE
Ring = Closed loop
Breaks in 2 places
If anterior, look posterior
CT is essential
COMMON TRAPS
✗Assuming X-ray is enough
✗Missing posterior injury
LIKELY FOLLOW-UPS
"What is the H-sign on MRI?"
"What are sacral insufficiency fractures?"
VIVA SCENARIOStandard
The Mortality Concern
EXAMINER
"Discuss the mortality risk."
EXCEPTIONAL ANSWER
**Similar Mortality to Hip Fractures.**
1. **Mortality Rate**: 1-year mortality 10-20% (similar to hip fractures).
2. **Causes**:
- *Immobility*: Bed rest leads to DVT, PE, Pneumonia, Deconditioning.
- *Frailty*: Often frail patients with multiple comorbidities.
- *Pain*: Severe pain limits mobility further.
3. **Prevention**:
- *Early Mobilization*: Weight-bearing as tolerated, Day 1.
- *DVT Prophylaxis*: Chemical + Mechanical.
- *Analgesia*: Adequate pain control to allow movement.
- *Orthogeriatric Care*: MDT approach. Medical optimization.
4. **Message**: Treat pubic rami fractures with the same urgency as hip fractures.
KEY POINTS TO SCORE
1-year mortality 10-20%
Immobility is the killer
Early mobilization is key
Orthogeriatric model
COMMON TRAPS
✗Dismissing as 'just' a rami fracture
✗Keeping patient in bed
LIKELY FOLLOW-UPS
"What is orthogeriatric care?"
"How do you treat osteoporosis?"
MCQ Practice Points
Ring Rule
Q: Why must you image the posterior pelvis if pubic rami are fractured? A: A ring cannot break in only one place. If the anterior ring (rami) is broken, there is likely a posterior injury (sacral fracture, SI injury).
LC-1
Q: What is the classic LC-1 injury pattern? A: Ipsilateral pubic rami fractures (anterior) + Ipsilateral sacral compression (posterior).
Treatment
Q: What is the treatment for isolated pubic rami fractures? A: Conservative - Analgesia, Early Mobilization (WBAT), DVT Prophylaxis, Osteoporosis Treatment.
Sacroplasty
Q: What is sacroplasty? A: Percutaneous cement injection into a symptomatic sacral insufficiency fracture to provide pain relief and allow mobilization.
Mortality
Q: What is the 1-year mortality for elderly patients with pelvic fragility fractures? A: 10-20%, similar to hip fractures. Immobility is the main risk factor.
Australian Context
- Orthogeriatric Model: Increasingly used for pelvic fragility fractures.
- Osteoporosis: PBS-subsidized treatment (Denosumab, Bisphosphonates) after fragility fracture.
- Rehabilitation: Hip fracture-style pathways being adopted.
High-Yield Exam Summary
Key Points
- •Ring breaks in 2 places
- •CT to assess posterior
- •LC-1 = Rami + Sacrum
- •Mobilize early
Treatment
- •Conservative most cases
- •Analgesia + Mobilize
- •DVT prophylaxis
- •Osteoporosis treatment
Sacroplasty
- •For painful sacral insufficiency fractures
- •Cement injection (PMMA)
- •Pain relief + Earlier Mobility
- •Consider for non-union sacral fractures
Mortality
- •10-20% at 1 year (elderly)
- •Similar mortality to hip fractures
- •Immobility is the killer
- •Fragility fracture = fall risk protocol