ESSEX-LOPRESTI INJURIES
Radial Head Fracture + IOM Disruption + DRUJ Instability | Longitudinal Forearm Instability | Do NOT Excise Radial Head
INJURY TRIAD
Critical Must-Knows
- Never excise radial head without replacement in Essex-Lopresti injury
- DRUJ must be assessed in ALL comminuted radial head fractures
- IOM central band is primary longitudinal stabilizer of forearm
- Proximal migration of radius indicates longitudinal instability
- Chronic cases extremely difficult to salvage - early diagnosis critical
Examiner's Pearls
- "Mechanism: Axial load through extended wrist (FOOSH)
- "Missed diagnosis leads to irreversible proximal migration
- "Radial head replacement is essential - not optional
- "IOM reconstruction techniques are salvage procedures
Clinical Imaging
Complete Essex-Lopresti Treatment
IOM Reconstruction (Chronic Cases)
Critical Essex-Lopresti Exam Points
NEVER Excise Radial Head
Cardinal rule: In Essex-Lopresti injuries, the radial head is the ONLY remaining longitudinal stabilizer. Excision without replacement leads to inevitable proximal radial migration, ulnar impaction, and progressive pain.
Always Check DRUJ
DRUJ examination is mandatory in ALL comminuted radial head fractures. Ballottement test, piano key sign, and comparison to contralateral side. Miss this and you miss the diagnosis.
Mechanism Understanding
FOOSH with axial load transmits force through the carpus, radius, radial head, fracturing it, then continues through the IOM and DRUJ, disrupting the longitudinal stability of the forearm.
Chronic is Catastrophic
Early diagnosis is critical. Chronic Essex-Lopresti with established proximal migration is extremely difficult to treat. Results of salvage procedures are generally poor.
At a Glance - Management Decision
| Presentation | IOM Status | DRUJ | Treatment |
|---|---|---|---|
| Isolated radial head fracture | Intact | Stable | Standard radial head management |
| Acute Essex-Lopresti | Disrupted | Unstable | Radial head replacement + DRUJ stabilization |
| Chronic - minimal migration | Disrupted | Unstable | RH replacement + possible IOM reconstruction |
| Chronic - established migration | Disrupted | Unstable | Salvage: IOM reconstruction, ulnar shortening |
| End-stage with arthritis | Disrupted | Destroyed | Consider one-bone forearm or arthroplasty |
RIDEssex-Lopresti Triad
Memory Hook:RID yourself of missing this diagnosis - always check all three components!
DRUJDRUJ Assessment
Memory Hook:DRUJ tells you how to check the DRUJ!
REPLACETreatment Principles
Memory Hook:REPLACE the radial head - it's the key to treatment!
Overview
The Essex-Lopresti injury is a rare but devastating pattern of forearm longitudinal instability characterized by radial head fracture, interosseous membrane (IOM) disruption, and distal radioulnar joint (DRUJ) instability. First described by Peter Essex-Lopresti in 1951, this injury represents complete disruption of the forearm's longitudinal stabilizing structures.
Epidemiology
Incidence:
- Less than 1% of all radial head fractures
- True incidence likely underestimated (frequently missed)
- Male predominance (high-energy mechanism)
- Most common in working-age adults (20-50 years)
Risk Factors:
- High-energy trauma
- Fall from height
- Motor vehicle accidents
- Industrial injuries
Mechanism of Injury
Primary Mechanism:
- Fall onto outstretched hand (FOOSH)
- Axial load through extended wrist
- Force transmission: Carpus to radius to radial head
Force Transmission:
- Radial head fractures under compressive load
- Force continues proximally through IOM
- Central band of IOM ruptures
- DRUJ disrupted as final stabilizer fails
Associated Injuries:
- Carpal fractures
- Capitellar injury
- Elbow dislocation
Anatomy and Pathophysiology
Forearm Longitudinal Stability
Understanding the longitudinal stabilizers of the forearm is essential for comprehending the Essex-Lopresti injury pattern.
Structure:
- Fibrous sheet connecting radius and ulna
- Fibers run obliquely (distal-ulnar to proximal-radial)
- Multiple distinct bands within the membrane
Central Band:
- Thickest and strongest portion
- Primary longitudinal stabilizer
- Located at junction of middle and proximal thirds
- Approximately 60% of longitudinal stability
Other Components:
- Proximal band (accessory band)
- Distal band
- Distal oblique bundle
Function:
- Transmits forces from radius to ulna
- Maintains radioulnar relationship
- Allows pronation and supination
The central band is the critical structure that ruptures in Essex-Lopresti injuries.
Exam Pearl
The interosseous membrane central band provides approximately 60% of forearm longitudinal stability, while the radial head provides approximately 30%. When both are disrupted, catastrophic proximal radial migration occurs.
Classification
Classification
Essex-Lopresti Triad:
Component 1 - Radial Head Fracture:
- Usually Mason Type III (comminuted)
- May be Mason Type IV (with dislocation)
- Occasionally Type II with significant comminution
Component 2 - IOM Disruption:
- Central band rupture (primary)
- May extend to proximal band
- Diagnosed clinically and by longitudinal instability
Component 3 - DRUJ Disruption:
- TFCC tear
- Dorsal and/or palmar radioulnar ligament rupture
- Results in DRUJ instability
All three components must be present for the diagnosis.
Mason Classification with Essex-Lopresti Implications
| Mason Type | Fracture Pattern | Essex-Lopresti Risk | Management |
|---|---|---|---|
| Type I | Marginal, non-displaced | Low | Non-operative, check DRUJ |
| Type II | Marginal, displaced | Moderate | Fix or replace, check DRUJ |
| Type III | Comminuted, unreconstructable | HIGH | Replace, high index of suspicion |
| Type IV | With elbow dislocation | HIGH | Replace, very high suspicion |
History
Mechanism:
- Fall from height
- Motor vehicle accident
- Fall onto outstretched hand
- Axial loading injury
Symptoms:
- Elbow pain (from radial head fracture)
- Forearm pain (often overlooked)
- Wrist pain (DRUJ involvement)
- Weakness of grip
- Pain with forearm rotation
Red Flags:
- High-energy mechanism
- Pain at both elbow AND wrist
- Significant swelling along entire forearm
- Inability to supinate/pronate
Pain at both elbow and wrist after FOOSH should raise suspicion.
Elbow Examination
Inspection:
- Swelling over lateral elbow
- Ecchymosis
- Deformity may indicate dislocation
Palpation:
- Tenderness over radial head
- Crepitus with rotation
- Assess for associated injuries
Range of Motion:
- Flexion/extension limited by pain
- Pronation/supination painful
- Mechanical block suggests loose bodies
Stability:
- Valgus stress testing
- Posterolateral rotatory drawer
- Check for associated ligament injury
Thorough elbow examination identifies the radial head fracture.
DRUJ Examination
CRITICAL - Often Missed:
Inspection:
- Ulnar head prominence
- Swelling at wrist
- Comparison to contralateral side
Palpation:
- Tenderness over DRUJ
- Tenderness over TFCC
- Ulnar styloid tenderness
Stability Tests:
- Piano key sign (dorsal prominence with pressure)
- Ballottement test (AP translation in neutral)
- Radius pull test (longitudinal instability)
- Compare to contralateral side
Forearm Squeeze Test:
- Pain at DRUJ with mid-forearm squeeze
- Indicates IOM disruption
DRUJ examination is MANDATORY in all comminuted radial head fractures.
ALWAYS examine the DRUJ in patients with comminuted radial head fractures. The Essex-Lopresti injury is frequently missed because the wrist is not examined. Pain at both elbow AND wrist should raise immediate suspicion.
Investigations
Imaging Studies
Elbow Views:
- AP and lateral of elbow
- Radial head view (45° oblique)
- Assess fracture comminution
Forearm Views:
- Full-length forearm AP and lateral
- Include both wrist and elbow
- Look for radioulnar dissociation
Wrist Views:
- PA and lateral of wrist
- Measure ulnar variance
- Positive variance suggests proximal migration
- Compare to contralateral side
Key Findings:
- Comminuted radial head fracture
- Positive ulnar variance (proximal migration)
- DRUJ widening or subluxation
- Ulnar impaction changes if chronic
Full-length forearm films are essential to assess longitudinal instability.
Exam Pearl
Positive ulnar variance on wrist radiographs indicates proximal radial migration. Always compare to the contralateral side and obtain full-length forearm films to assess longitudinal instability.
Management Algorithm
Treatment Decision Making
Surgical Treatment (Standard of Care):
Step 1 - Radial Head:
- ORIF if reconstructable (rare in Essex-Lopresti)
- Replacement with metal prosthesis if comminuted
- NEVER excise without replacement
Step 2 - Assess DRUJ Intraoperatively:
- After radial head addressed, test DRUJ stability
- Ballottement in neutral rotation
- Compare to contralateral side
Step 3 - DRUJ Stabilization:
- If stable: immobilize in supination 4-6 weeks
- If unstable: transfix with K-wires or suture repair
- Long-arm cast in supination
Post-operative:
- Long-arm cast 4-6 weeks
- Elbow motion can begin earlier
- Forearm rotation protected
Acute surgical treatment focuses on radial head replacement and DRUJ stabilization.
Acute Principles
Goals:
- Replace radial head
- Restore length
- Stabilize DRUJ
- Protect healing
Timing:
- Surgery within 2 weeks ideal
- Earlier is better
- Delayed surgery associated with worse outcomes
Avoid These Errors
Critical Mistakes:
- Excising radial head without replacement
- Missing the DRUJ injury
- Inadequate immobilization
- Failing to assess longitudinal stability
Consequences:
- Irreversible proximal migration
- Ulnar impaction syndrome
- Chronic pain and disability
Surgical Technique
Operative Procedures
Patient Positioning:
- Supine with arm on hand table
- Tourniquet on upper arm
- Fluoroscopy available
Approach:
- Kocher approach (between anconeus and ECU)
- Protect lateral ulnar collateral ligament
- Identify and preserve annular ligament
Technique:
- Excise radial head fragments
- Preserve annular ligament remnants
- Ream medullary canal
- Trial implant sizing
- Confirm length with fluoroscopy
- Seat final implant
- Close annular ligament if possible
Intraoperative Assessment:
- Full ROM without impingement
- Stable tracking
- Test DRUJ stability
Radial head replacement technique is critical for successful outcome.
Exam Pearl
When sizing the radial head prosthesis, the lateral ulnohumeral joint should be restored. Overlengthening causes capitellar wear and pain; underlengthening fails to prevent proximal migration.
Complications
Potential Complications
Most Common Problem:
- Failure to examine DRUJ
- Isolated radial head excision performed
- Progressive proximal migration
Consequences:
- Ulnar impaction syndrome
- Wrist pain
- Grip weakness
- Chronic forearm instability
Prevention:
- High index of suspicion
- Examine DRUJ in ALL comminuted RH fractures
- Full-length forearm radiographs
Missed diagnosis is the most common and devastating complication.
Radial head excision without replacement in Essex-Lopresti injury leads to inevitable proximal radial migration and chronic disability. This error is essentially irreversible - prevention through proper diagnosis is key.
Postoperative Care
Rehabilitation Protocol
Goals:
- Protect DRUJ stability
- Allow soft tissue healing
- Prevent proximal migration
Immobilization:
- Long-arm cast or splint
- Forearm in supination
- Elbow at 90 degrees
Motion:
- Elbow flexion/extension out of cast (if stable)
- No forearm rotation
- Shoulder and hand exercises
K-wire Removal:
- If DRUJ pinned, remove at 6 weeks
- Under local anesthesia
Protection phase prioritizes DRUJ healing.
Outcomes
Expected Results
Early Diagnosis and Treatment:
- Fair to good outcomes in 60-80%
- Better than chronic treatment
- Restoration of stability achievable
Functional Outcomes:
- ROM: Usually 80-90% of contralateral
- Grip strength: 70-80% of contralateral
- Return to work: Variable, often with restrictions
Complications:
- Migration despite treatment: 10-30%
- Revision surgery: 15-25%
- Chronic pain: 20-40%
Acute treatment provides best chance for acceptable outcome.
Evidence Base
Key Studies
Essex-Lopresti - Original Description
- First description of the injury pattern
- Two cases presented with radial head excision leading to migration
- Recognized triad of RH fracture, IOM disruption, DRUJ injury
- Emphasized importance of recognizing the pattern
Hotchkiss et al. - Treatment Algorithm
- Proposed treatment algorithm based on injury timing
- Emphasized acute radial head replacement
- Described DRUJ stabilization techniques
- Warned against radial head excision
Trousdale et al. - Radial Head Replacement
- Outcomes of radial head replacement for Essex-Lopresti
- Demonstrated importance of early replacement
- Late replacement had worse outcomes
- Proximal migration continued in delayed cases
Marcotte and Osterman - IOM Reconstruction
- Review of IOM reconstruction techniques
- Various graft options described
- Results variable but may help chronic cases
- Salvage procedure with limited outcomes
Skahen et al. - IOM Biomechanics
- Biomechanical study of forearm longitudinal stability
- Central band provides approximately 71% of IOM stiffness
- Radial head provides 28% of longitudinal stability
- Sequential sectioning demonstrated importance of each structure
Viva Scenarios
Viva Scenarios
Exam Viva Scenarios
Practice these scenarios to excel in your viva examination
Acute Diagnosis
"A 35-year-old man falls from a ladder onto his outstretched hand. He has a comminuted radial head fracture. How would you assess for an Essex-Lopresti injury?"
Acute Management
"You have confirmed an Essex-Lopresti injury in the patient from the previous scenario. What is your surgical plan?"
Missed Injury (Chronic)
"A patient presents 6 months after a radial head excision for what was thought to be an isolated comminuted radial head fracture. He now has wrist pain and grip weakness. Radiographs show 8mm positive ulnar variance. What has happened and how would you manage this?"
Functional Anatomy
"Describe the anatomy of the interosseous membrane and its role in forearm stability."
MCQ Practice
High-Yield Exam Points
High Yield
Q: What is the most important examination to perform in a patient with a comminuted radial head fracture?
A: DRUJ stability assessment is CRITICAL in all comminuted radial head fractures to rule out Essex-Lopresti injury. Use ballottement test, piano key sign, and always compare to the contralateral side. Missing this examination leads to missed diagnosis with catastrophic consequences.
High Yield
Q: In an acute Essex-Lopresti injury, what is the most important surgical intervention and why?
A: Radial head replacement is essential. The radial head is the only remaining longitudinal stabilizer after IOM rupture. Excision without replacement leads to inevitable proximal radial migration, ulnar impaction, and chronic disability. This is a NEVER excise scenario.
High Yield
Q: What percentage of forearm longitudinal stability is provided by the IOM central band versus the radial head?
A: The IOM central band provides approximately 60-70% of forearm longitudinal stability, while the radial head provides approximately 30%. When both are disrupted, catastrophic instability results with proximal migration of the radius.
High Yield
Q: What is the most common reason Essex-Lopresti injuries are missed, and how can this be prevented?
A: Failure to examine the DRUJ is the most common reason these injuries are missed. The wrist is simply not examined in patients presenting with elbow injuries. Prevention: ALWAYS perform DRUJ examination in ALL comminuted radial head fractures and obtain full-length forearm radiographs.
High Yield
Q: A patient had radial head excision 6 months ago. Now has wrist pain and 7mm positive ulnar variance. What happened and what are the management options?
A: This is a missed Essex-Lopresti injury with established proximal migration. Management options include: 1) Radial head replacement + IOM reconstruction (best salvage option), 2) Ulnar shortening osteotomy + DRUJ procedure, 3) One-bone forearm (extreme salvage). All have poor outcomes compared to acute treatment - this emphasizes the critical importance of early diagnosis.
High Yield
Q: How do you assess DRUJ stability intraoperatively after radial head replacement?
A: Test DRUJ stability in neutral rotation using ballottement test. Compare to contralateral side. If stable, immobilize in supination for 6 weeks. If unstable, perform K-wire transfixion with 2 parallel wires from radius to ulna, forearm in supination, or consider direct TFCC repair.
Australian Context
Australian Context
Essex-Lopresti injuries in Australian practice present unique challenges related to diagnosis, treatment access, and rehabilitation within the Australian healthcare system.
The injury typically occurs in working-age adults sustaining high-energy trauma, including falls from heights in construction and mining industries, and motor vehicle accidents. Australian workplace safety regulations through Safe Work Australia emphasize fall prevention, but these injuries continue to occur. Early recognition is critical, and Australian emergency departments should maintain high suspicion for this injury pattern in patients presenting with comminuted radial head fractures.
Radial head replacement surgery requires specific implants and expertise. Major metropolitan trauma centers typically have access to modern radial head prostheses and surgeons experienced in their use. Regional and rural areas may require transfer to tertiary centers for definitive management. The retrieval system and telehealth consultation capabilities support appropriate triage and transfer when needed.
WorkCover systems across Australian states provide coverage for work-related Essex-Lopresti injuries. The complexity of this injury and potential for chronic disability means that case management and medicolegal considerations are common. Permanent impairment assessment often follows, with typical outcomes reflecting significant functional limitations. Clear documentation of the injury pattern, treatment provided, and functional outcomes is essential.
Rehabilitation services through hospital physiotherapy departments and private practitioners support recovery. The prolonged rehabilitation required and potential for chronic symptoms necessitates multidisciplinary care. Return to work programs must account for the limitations in grip strength and forearm rotation that often persist despite optimal treatment.
Essex-Lopresti Injuries - Exam Quick Reference
High-Yield Exam Summary