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 login to view 3 more bullets pathoanatomy login to view 4 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 login to view 1 more bullet 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 login to view 1 more bullet Medial collateral ligament three components login to view 6 more bullets Lateral collateral ligament inserts on supinator crest distal to lesser sigmoid notch the primary restraint to posterolateral rotatory instability four components login to view 4 more bullets 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 login to view 10 more bullets Operative ORIF versus radial head arthroplasty, LCL reconstruction, coronoid ORIF, possible MCL reconstruction login to view 4 more bullets Techniques ORIF vs replacement of radial head, coronoid ORIF, LCL reconstruction, and possible MCL reconstruction approach login to view 4 more bullets technique login to view 27 more bullets postoperative login to view 10 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 login to view 1 more bullet 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