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Rehabilitation After ORIF of Elbow Dislocations

Cynthia Watkins, PT, DPT, CHT, and Charles L. Getz, MD

axially loaded. In addition, the valgus-carrying angle and slight degree of flexion convert the axial load into a valgus thrust. This mechanism results in injury of the stabilizing structures around the elbow. O’Driscoll described the stages of elbow instability as beginning with a failure of the LUCL, with pro- gressive disruption of the anterior and posterior capsule. In severe cases, the medial ulnar collateral ligament (MUCL) is also injured. This unlocks the forearm from the humerus, and allows the radial head to dislocate behind the capitellum. In cases of complex instability, the radial head is driven into the capitellum and the coronoid into the trochlea before the forearm is fully disengaged, resulting in various degrees of fracture of the radial head and coronoid in addition to the collateral ligament injuries. The terrible triad injury pattern consists of an elbow dislocation, radial head fracture, and coronoid fracture. PRLI is a relatively rare late sequelae of traumatic elbow dis- location or subluxation. It occurs when the LCL complex fails to heal sufficiently to prevent the forearm from rotating away from the humerus, resulting in either recurrent frank disloca- tions or subluxations of the elbow. Varus posteromedial rota- tory instability (VPRI) is caused by a varus load, which results in failure of the LCL under tension and fracture of the medial ulna joint line due to compression of the coronoid against the medial aspect of the trochlea. Simple Elbow Dislocations For the majority of patients with simple elbow dislocations, a brief period of immobilization followed by protected early range of motion (ROM) will result in a favorable outcome. In rare cases, the elbow will not be stable even with the elbow in 90 ° of flexion and the forearm pronated. These patients require operative stabilization of the elbow. Operative Treatment

Introduction Elbow joint stability is dependent on a highly congruent skel- etal articulation and collateral ligaments. Dislocations of the elbow are relatively common, being the second most com- monly dislocated major joint. Most simple elbow dislocations are managed with closed reduction, a brief period of immobi- lization, and early protected rehabilitation. Elbow dislocations associated with fractures of the radial head and the coronoid are complex injuries that are much more likely to require surgical intervention. Relevant Anatomy The elbow is stabilized by both the bony congruency of the joint and the periarticular soft-tissue structures. The soft- tissue structures on the medial side (Figure 19.1) are the medial collateral ligament (MCL) complex and the flexor pro- nator mass. The lateral (Figure 19.2) side soft tissues include the lateral collateral ligament complex (LCL) and the exten- sor and supinator muscular complex. The primary restraint to valgus instability is the radial capitellar joint, while the MCL is a secondary stabilizer that becomes the primary stabilizer if the radial head is removed. The bony congruency of the ulnar trochlear articulation is the primary restraint to varus stress, with the LCL being a secondary stabilizer. Supination and axial loading of the forearm causes the ulna and radial head to rotate away from the distal humerus, with the radial head translating posterior to the capitellum and the lateral ulna rotating away from the lateral trochlea. The lat- eral ulnar collateral ligament (LUCL) is the primary stabilizer to prevent this instability pattern, known as posterolateral rotatory instability (PRLI). Most elbow dislocations occur as a result of a fall onto an outstretched arm. The forearm is forcibly supinated and

Dr. Getz or an immediate family member is a member of a speakers’ bureau or has made paid presentations on behalf of Mitek and Zimmer; serves as a paid consultant to Cayenne Medical; serves as an unpaid consultant to Zimmer; has stock or stock options held in OBERD; and has received research or institutional support from Integra, Rotation Medical, and Zimmer. Neither Dr. Watkins nor any immediate family member has received anything of value from or has stock or stock options held in a commercial company or institution related directly or indirectly to the subject of this article.

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© 2018 American Academy of Orthopaedic Surgeons

Postoperative Orthopaedic Rehabilitation

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