summary Terrible Triad Injury of Elbow is a traumatic injury pattern of the elbow characterized by elbow dislocation, radial head/neck fracture, and a coronoid fracture. Diagnosis can be made with plain radiographs of the elbow. CT studies are helpful for surgical planning. Treatment is generally ORIF versus radial head arthroplasty, LCL reconstruction, coronoid ORIF, and possible MCL reconstruction. Etiology Characterized by presence of elbow dislocation (often associated with posterolateral dislocation or LCL injury ) radial head or neck fracture coronoid fracture Pathophysiology mechanism fall on supinated forearm and extended arm that results in a combination of login to view 2 more bullets pathoanatomy structures of elbow fail from lateral to medial login to view 3 more bullets Anatomy Radial head a secondary restraint to posterolateral rotatory instability (PLRI) secondary valgus stabilizer forearm in neutral rotation, lateral portion of articular margin devoid of cartilage roughly between radial styloid and listers tubercle Coronoid process provides an anterior and varus buttress to ulnohumeral joint resists posterior subluxation beyond 30 deg of flexion fracture fragment typically has some anterior capsule attached useful in repair Medial collateral ligament three components anterior bundle login to view 3 more bullets posterior bundle transverse ligament Lateral collateral ligament inserts on supinator crest distal to lesser sigmoid notch the primary restraint to posterolateral rotatory instability four components lateral ulnar collateral ligament (most important for stability) radial collateral ligament annular ligament accessory collateral ligament when injured is usually avulsed off of the lateral epicondyle Presentation Symptoms patients complain of pain, clicking and locking with elbow in extension Physical exam possible varus / valgus instability patterns distal radial ulnar joint must be evaluated for possible Essex-Lopresti injury Imaging Radiographs evaluate for concentricity of ulnohumeral and radiocapitellar joints line drawn through center of radial neck should intersect the center of the capitellum regardless of radiographic projection evaluate lateral radiograph for coronoid fracture need prereduction and postredcution films consider PA and lateral films of wrist and forearm when indicated CT often utilized for better evaluation of coronoid fracture 3D imaging for determining fracture line propagation Treatment Nonoperative immobilization in 90 deg of flexion for 7-10 days indications (rare) login to view 4 more bullets techniques login to view 4 more bullets Operative ORIF versus radial head arthroplasty, LCL reconstruction, coronoid ORIF, possible MCL reconstruction indications login to view 3 more bullets Techniques ORIF vs replacement of radial head, coronoid ORIF, LCL reconstruction, and possible MCL reconstruction approach posterior skin incision advantageous login to view 3 more bullets technique radial head ORIF vs. arthroplasty login to view 9 more bullets coronoid ORIF login to view 6 more bullets LCL repair login to view 6 more bullets MCL repair login to view 2 more bullets postoperative elbow fixators - hinged or static login to view 1 more bullet immobilization login to view 2 more bullets rehabilitation login to view 4 more bullets Complications Instability more common following type I or II coronoid fractures Failure of internal fixation most common following repair of radial neck fractures poor vascularity leading to osteonecrosis and nonunion Post-traumatic stiffness very common complication initiate early ROM to prevent Heterotopic ossification consider prophylaxis in pts with head injury or in setting of revision surgery Post-traumatic arthritis due to chondral damage at time of injury and/or residual instability Prognosis Historically poor outcomes secondary to persistent instability stiffness arthrosis