A Monteggia fracture is a fracture of the proximal ulna with concomitant dislocation of the radial head at the radiocapitellar joint. It accounts for approximately 0.7% of all elbow fractures in adults and 1.5–3% of childhood elbow injuries. [1-3] This is a commonly missed injury — the radial head dislocation is frequently overlooked, and delayed diagnosis leads to significantly worse outcomes. [1][4]
1. History
- Mechanism of injury: Fall on an outstretched hand (FOOSH) with the elbow extended and forearm hyperpronated; also direct blow to the posterior forearm ("nightstick" mechanism) [5]
- Key HPI: Mechanism (fall height, direct blow, MVC), hand dominance, time since injury, prior forearm/elbow injuries
- Symptom characterization: Acute elbow and forearm pain, inability to flex/extend elbow or pronate/supinate forearm, swelling, deformity
- Ask about numbness or weakness in the hand — specifically inability to extend the wrist or fingers (posterior interosseous nerve [PIN] palsy) [6-7]
- In children: May present with subtle findings; plastic deformation of the ulna (bowing without visible fracture line) can cause radial head dislocation that is easily missed [4]
2. Alarm Features
- Open fracture — skin breach over the proximal forearm or elbow
- Neurovascular compromise — PIN palsy (inability to extend fingers/wrist at MCP joints with intact wrist extension via ECRL), AIN palsy, or radial nerve injury [6]
- Compartment syndrome — tense forearm, pain with passive finger extension, paresthesias
- Irreducible radial head — may indicate soft tissue interposition (annular ligament, nerve) requiring open surgery [1][8]
- Concomitant ipsilateral fractures (distal radius, supracondylar humerus) present in ~7% of pediatric cases [9]
3. Medications
- Acute pain management: NSAIDs, acetaminophen, opioids for severe pain in the ED
- Procedural sedation agents for closed reduction (ketamine, propofol, midazolam/fentanyl)
- Perioperative antibiotics if open fracture (cefazolin ± aminoglycoside per Gustilo-Anderson grade)
- Avoid: Anticoagulants should be noted as they may complicate surgical planning
- Post-op: Scheduled NSAIDs/acetaminophen with short-course opioids as needed
4. Diet
- No specific acute dietary considerations
- Adequate calcium and vitamin D intake for bone healing
- Ensure adequate protein and caloric intake during recovery, especially in pediatric and elderly patients
5. Review of Systems
- Neurologic: Numbness/tingling in radial nerve distribution, weakness of finger/wrist extension (PIN), weakness of thumb IP flexion and index DIP flexion (AIN) [6]
- Vascular: Coolness, pallor, or diminished pulses distally
- MSK: Pain or deformity at the wrist (rule out concomitant distal radius fracture or DRUJ injury)
- Constitutional: Mechanism-related — polytrauma screening if high-energy mechanism
6. Collateral History and Family History
- Witnessed mechanism of injury (especially in children — consider non-accidental trauma if mechanism inconsistent with injury pattern)
- In pediatric patients, prior forearm injuries or elbow complaints may suggest a chronic/missed Monteggia lesion [4][10]
- Family history is generally not contributory unless underlying bone disease (e.g., osteogenesis imperfecta) is suspected
7. Risk Factors
- Pediatric population: Peak incidence ages 4–10 years; Bado type I (anterior dislocation) most common in children [3][9]
- Adults: Bado type II (posterior dislocation) most common; mean age ~52 years; often associated with higher-energy mechanisms [11]
- Falls from height, motor vehicle collisions, sports injuries
- Osteoporosis in elderly patients increases fracture comminution risk
- Risk factors for associated nerve injury: age ≥8 years, lateral radial head dislocation, open fracture, comminuted ulnar fracture [6]
8. Differential Diagnosis
- Isolated ulnar shaft fracture ("nightstick fracture") — must always obtain elbow radiographs to rule out radial head dislocation [1]
- Galeazzi fracture — distal/mid-radius fracture with DRUJ dislocation (the "reverse" forearm fracture-dislocation) [5]
- Terrible triad of the elbow — elbow dislocation + radial head fracture + coronoid fracture [12]
- Isolated radial head dislocation (congenital vs. traumatic)
- Elbow dislocation without fracture
- Essex-Lopresti injury — radial head fracture with interosseous membrane disruption and DRUJ instability
- Supracondylar humerus fracture (especially in children)
- Non-accidental trauma in pediatric patients with inconsistent history
9. Past Medical History
- Prior forearm or elbow fractures, dislocations, or surgeries
- History of osteoporosis or metabolic bone disease
- Connective tissue disorders (Ehlers-Danlos, Marfan)
- Previous missed Monteggia — chronic Monteggia becomes irreducible after 2–3 weeks and requires complex reconstruction [1][10]
- Anticoagulant or antiplatelet use (surgical planning)
10. Physical Exam
- Inspection: Swelling, ecchymosis, deformity of the elbow and forearm; assess for open wounds
- Palpation: Tenderness over the proximal ulna; palpate the radial head in the antecubital fossa — an anteriorly dislocated radial head may be palpable [5]
- Range of motion: Markedly limited elbow flexion/extension and forearm pronation/supination
- Neurovascular exam (critical):
- PIN: Test finger extension at MCP joints and thumb extension (thumb "hitchhiker" sign) [5-6]
- AIN: Test thumb IP flexion and index finger DIP flexion ("OK" sign)
- Radial and ulnar pulses, capillary refill
- Compartment assessment: Palpate forearm compartments for tenseness; pain with passive finger extension
11. Lab Studies
- Labs are generally not required for isolated Monteggia fractures
- Pre-operative labs if surgery planned: CBC, BMP, coagulation studies, type and screen
- In polytrauma: Lactate, hemoglobin, coagulation panel
- Consider CRP/ESR if concern for pathologic fracture or infection (chronic presentation)
12. Imaging
- First-line: AP and lateral radiographs of the elbow AND full-length forearm (both joints must be visualized) [1-2]
- Key radiographic sign: The radiocapitellar line — a line drawn through the radial shaft and radial head should bisect the capitellum on ALL views; failure to do so indicates radial head dislocation [2]
- Radial head dislocation can occur even with minimal ulnar displacement — scrutinize carefully [1]
- CT without contrast: Indicated for complex/comminuted fractures (especially Bado type II in adults) to characterize fracture morphology, coronoid involvement, and radial head fragmentation for surgical planning [13-14]
- MRI: Useful in chronic/missed cases to evaluate annular ligament integrity, radial head/notch morphology, and nerve pathology [10][15]
- When imaging is unnecessary: Imaging is always indicated when Monteggia fracture is suspected
13. Special Tests
Bado Classification (the standard classification system): [2][13][16-17]
- Jupiter subclassification of Bado type II further characterizes coronoid involvement and proximal ulna comminution, which guides surgical complexity [13]
- Radiocapitellar line test on radiographs (described above) [2]
- Elbow extension test: Inability to fully extend the elbow while seated with shoulders at 90° flexion suggests occult fracture [14]
- Mayo Elbow Performance Score (MEPS): Used for outcome assessment post-treatment [18-19]
14. ECG
- Not routinely indicated for isolated Monteggia fractures
- Obtain if procedural sedation or general anesthesia is planned, per institutional protocol
- Standard pre-operative ECG in elderly patients or those with cardiac history
15. Assessment
- Monteggia fractures are orthopedic emergencies that require prompt recognition and treatment [1][20]
- The most commonly missed component is the radial head dislocation — up to 72% of Monteggia-equivalent injuries (plastic deformation with radial head dislocation) are missed at initial presentation [4]
- In children: Bado type I predominates; outcomes are generally excellent with timely treatment [3][21]
- In adults: Bado type II predominates; associated radial head and coronoid fractures significantly increase complexity and worsen prognosis [11][13]
- Delayed diagnosis beyond 2–3 weeks leads to chronic Monteggia, which is far more difficult to treat with higher complication rates [1][10][19]
- Complications: Ulnar non-union (28%), limited ROM (22%), recurrent dislocation, proximal radioulnar synostosis, PIN palsy, and late osteoarthritis [11][16][22]
16. Treatment Plan
Initial stabilization (ED)
- Splint in long-arm posterior splint with elbow at 90° flexion and forearm in supination (for Bado type I)
- Neurovascular exam before and after any manipulation
- Adequate analgesia
Pediatric management
- Greenstick/plastic deformation ulnar fractures: Closed reduction and long-arm cast immobilization is often successful [2][21]
- Complete ulnar fractures: Trend toward operative fixation (ESIN or plate) to maintain reduction, though a trial of closed reduction with close follow-up is reasonable [3][21][23]
- Closed reduction of the ulna typically reduces the radial head indirectly [1]
Adult management
- All adult Monteggia fractures require operative fixation — closed reduction alone leads to unacceptable rates of angulation and shortening [2][11][13]
- Ulnar fixation: Plate and screws (locking plates preferred, associated with fewer non-unions and revisions) [11][16]
- Radial head: ORIF if reconstructable; radial head arthroplasty if comminuted beyond repair; excision is a last resort [11][13]
- Coronoid fracture fixation is critical for ulnohumeral stability in Bado type II injuries [11][13]
- Anatomic reduction of the ulna indirectly reduces the radiocapitellar joint [13]
Chronic/missed Monteggia
- Open reduction of radial head + corrective ulnar osteotomy ± annular ligament reconstruction [1][10][24-25]
- Outcomes are more variable; interval >6 months from injury significantly increases risk of re-dislocation [10]
17. Disposition
- Admission criteria: Open fractures, polytrauma, neurovascular compromise, need for urgent/emergent operative fixation
- Observation: Post-reduction in children if closed reduction performed in ED — ensure radiographic confirmation of maintained reduction
- Discharge criteria: Stable closed injury, adequate splinting, reliable follow-up within 5–7 days with orthopedics, intact neurovascular exam
- Specialist consultation triggers:
- All Monteggia fractures warrant orthopedic consultation in the ED [1][13]
- Irreducible radial head → urgent open reduction (may indicate interposition) [1][8]
- Neurovascular compromise → emergent consultation
- Adult Monteggia fractures → operative planning
18. Follow Up / Return Precautions
- Follow-up timing: Orthopedic follow-up within 5–7 days with repeat radiographs to confirm maintained reduction [21]
- Serial radiographs at 1, 2, 4, and 6 weeks post-injury/surgery
- Return immediately for: Increasing pain, numbness/tingling, inability to move fingers, color change of the hand, worsening swelling, fever, wound drainage
- Expected recovery:
- Pediatric: Excellent outcomes expected with timely treatment; full ROM typically restored [3][19][21]
- Adult: Mean revision rate ~23%; most achieve good-to-excellent functional outcomes with anatomic fixation [11][16]
- Nerve injuries (PIN, AIN) associated with Monteggia fractures typically resolve spontaneously within ~64 days (range 8–150 days); early operative nerve exploration is generally unnecessary [6]
- Long-term: Monitor for late complications including elbow stiffness, heterotopic ossification, radioulnar synostosis, and post-traumatic arthritis [11][22]
References
1. Monteggia Injuries. — Delpont M, Louahem D, Cottalorda J. Orthopaedics & Traumatology, Surgery & Research : OTSR. 2018.
2. Monteggia Fractures in Pediatric and Adult Populations. — Beutel BG. Orthopedics. 2012.
3. The Three Step Approach to the Management of Acute Pediatric Monteggia Lesions. — Hetthéssy JR, Sebők B, Vadász A, Kassai T. Injury. 2021.
4. Missed Diagnosis and Acute Management of Radial Head Dislocation With Plastic Deformation of Ulna in Children. — Singh V, Dey S, Parikh SN. Journal of Pediatric Orthopedics. 2020.
5. Common Fractures of the Radius and Ulna. — Patel DS, Statuta SM, Ahmed N. American Family Physician. 2021.
6. Examining Preoperative Risk Factors for Nerve Injury in Pediatric Monteggia Fracture-Dislocations. — Amaral JZ, Touban BM, Schultz RJ, et al. The Journal of Bone and Joint Surgery. American Volume. 2025.
7. Type III Monteggia Fracture With Posterior Interosseous Nerve Injury in a Child: A Case Report. — Wang J, Chen M, Du J. Medicine. 2017.
8. A Neurologic Complication Following Monteggia Fracture. — Spar I. Clinical Orthopaedics and Related Research. 1977.
9. Incidence, Characteristics, and Management of Concomitant Ipsilateral Upper-Extremity Fractures in Pediatric Monteggia Fracture-Dislocations: A 13-Year Single-Institution Case Series. — Amaral JZ, Moran J, Diejomaoh RM, et al. The Journal of Bone and Joint Surgery. American Volume. 2025.
10. Missed Monteggia Fractures in Children Treated by Open Reduction of the Radial Head and Corrective Osteotomy of the Ulna. — Cao S, Dong ZG, Liu LH, et al. Scientific Reports. 2022.
11. Monteggia Fractures in Adults. — Ring D, Jupiter JB, Simpson NS. The Journal of Bone and Joint Surgery. American Volume. 1998.
12. The Radiological Findings in Complex Elbow Fracture-Dislocation Injuries. — Al-Ani Z, Tham JL, Ooi MWX, et al. Skeletal Radiology. 2022.
13. Complex Monteggia Fractures in the Adult Cohort: Injury and Management. — Kim JM, London DA. The Journal of the American Academy of Orthopaedic Surgeons. 2020.
14. ACR Appropriateness Criteria® Acute Elbow and Forearm Pain. — Chen KC, Ha AS, Bartolotta RJ, et al. Journal of the American College of Radiology : JACR. 2024.
15. Magnetic Resonance Imaging Manifestations of Annular Ligament Injuries in Children With Monteggia Fractures. — Yue J, Mu W, Sun Z, et al. Journal of Pediatric Orthopedics. 2023.
16. Monteggia Fractures and Monteggia-Like-Lesions: A Systematic Review. — Weber MM, Rosteius T, Schildhauer TA, Königshausen M, Rausch V. Archives of Orthopaedic and Trauma Surgery. 2023.
17. Monteggia Fracture Dislocations: A Historical Review. — Rehim SA, Maynard MA, Sebastin SJ, Chung KC. The Journal of Hand Surgery. 2014.
18. Treatment of Monteggia-Like-Lesion in a Young Patient: A Case Report. — Santoso ARB, Huwae TECJ, Wijaya AEP, et al. Medicine. 2021.
19. Comparison of Treatment Methods for Pediatric Monteggia Fracture: Met vs Missed Radial Head Dislocation. — He JP, Hao Y, Shao JF. Medicine. 2019.
20. Monteggia Fracture Associated With Ipsilateral Intercondylar Distal Humeral Fracture With Posterior Interosseous Nerve Palsy: Case Report, Medico-Legal Implications, and Methodological Assessment Analysis. — Basile G, Fozzato S, Bianco Prevot L, et al. European Review for Medical and Pharmacological Sciences. 2023.
21. Operative Versus Nonoperative Management of Acute Pediatric Monteggia Injuries With Complete Ulna Fractures. — Hart CM, Alswang J, Bram J, et al. Journal of Pediatric Orthopedics. 2021.
22. Chronic Monteggia. — Soni JF, Valenza WR, Pavelec AC. Current Opinion in Pediatrics. 2019.
23. Successful Strategies for Managing Monteggia Injuries. — Bae DS. Journal of Pediatric Orthopedics. 2016.
24. Surgical Management of Neglected Monteggia Fractures in Children. — Martínez-Álvarez S, Galán-Olleros M, Arias-Martínez P, et al. Journal of Pediatric Orthopedics. 2025.
25. Surgical Reconstruction of Missed Monteggia Lesions in Children. — Zheng ET, Waters PM, Vuillermin CB, Williams K, Bae DS. Journal of Pediatric Orthopedics. 2020.