Summary Radial head and neck fractures in children are relatively common traumatic injuries that usually affect the radial neck (metaphysis) in children 9-10 years of age. Diagnosis can be made with plain radiographs of the elbow. Treatment can be nonoperative or operative depending on the degree of angulation, translation and displacement. Epidemiology Incidence 5-10% of all pediatric elbow fractures and 1% of pediatric fractures overall 90% of all cases involve physis or metaphysis fractures involving the articular surface are much less common in patients with open physes (4-7%) incidence increases once physis closes (52-96%) Demographics median age is 9-10 years no difference in incidence between sexes Etiology Pathophysiology mechanism usually associated with an extension and valgus loading injury of the elbow elbow dislocation Associated conditions elbow dislocation olecranon fracture medial epicondyle fracture forearm compartment syndrome Anatomy There are 6 ossification centers around the elbow joint age of ossification is variable but occurs in the following order (C-R-I-T-O-E) at an average age of (years) Capitellum (1 yr.) Radius (3 yr.) Internal or medial epicondyle (5 yr.) Trochlea (7 yr.) Olecranon (9 yr.) External or lateral epicondyle (11 yr.) Ossification center of radial head appears between and 3 and 5 years of age may be bipartite radial head fuses with radial shaft between ages of 16 and 18 years Ligaments annular ligament in continuity with the joint capsule covers epiphysis and physis protects relatively weaker physis but creates stress riser at the metaphysis, causing fractures to preferentially occur at the neck Epiphyseal cartilage thick cartilage layer thought to be relatively protective against intra-articular extension Classification O'Brien Classification Type I < 30 degrees Type II 30-60 degrees Type III > 60 degrees Judet Classification Type I Undisplaced Type II < 30 degrees Type III 30-60 degrees Type IVa 60-80 degrees Type IVb More than 80 degrees Chambers Classification Group 1: Primary displacement of radial head (most common) Valgus Injury A: Physeal injury - Salter-Harris I or II B: Intra-articular -Salter-Harris III or IV C: metaphyseal fracture Elbow Dislocation D: reduction injury E: dislocation injury Group 2: Primary displacement of radial neck Monteggia variant Group 3: Stress injury Osteochondritis dissecans Presentation Symptoms elbow pain refusal to move Physical exam inspection lateral swelling motion pain exacerbated by motion, especially supination and pronation. must have high suspicion for forearm compartment syndrome pain may be referred to the wrist Imaging Radiographs recommended views AP and lateral of the elbow radiocapitellar line line drawn along the radial axis on a lateral view of the elbow should intersect capitellum not reliable in young children, especially on AP view lateral humeral line line tangential to the lateral edge of the ossified lateral condyle, parallel to the axis of the distal humeral shaft lies lateral to the radial neck in normal elbows more reliable measure of radiocapitellar alignment especially in younger children radiocapitellar (Greenspan) view oblique lateral performed by placing the arm on the radiographic table with the elbow flexed 90 degrees and the thumb pointing upward beam is directed 45 degrees proximally findings nondisplaced fractures may be difficult to visualize beware of fracture with radial head that is flipped 180 degrees look for fat pad signs anterior fat pad may be normal, but a posterior fat pad sign is always pathologic and should be treated as an occult fracture a portion of the radial neck is extra-articular and therefore an effusion and fat pad signs may be absent CT indications useful in older children with comminuted radial head fractures may assist with preoperative planning MRI indications rarely used may be useful for characterizing pre-ossified elbow in the absence of an arthrogram useful for characterizing compression fractures of the anterior radial head, which are associated with ligamentous injury must weigh benefits against high cost Treatment Nonoperative immobilization alone indications <30 degrees of angulation <3mm translation technique immobilize in long arm cast or splint without reduction follow-up 7-21 days of immobilization followed by range of motion closed reduction and immobilization indications >30 degrees of angulation techniques closed reduction followed by immobilization in long arm cast or splint if an adequate reduction is achieved Operative closed percutaneous reduction indications > 30° of residual angulation following closed reduction > 3-4 mm of translation < 45° of pronation and supination outcomes improved outcomes with younger patients, lesser degrees of angulation, and isolated radial neck fractures open reduction indications fracture that cannot be adequately reduced to <45 degrees angulation with closed or percutaneous methods outcomes open reduction has been associated with a greater loss of motion, increased rates of osteonecrosis and synostosis compared with closed reduction (though this is controversial as higher rates of open reduction are also seen with worse fractures) Techniques Closed Reduction and Immobilization reduction techniques Patterson maneuver hold the elbow in extension and apply distal traction with the forearm supinated and pull the forearm into varus while applying direct pressure over the radial head Israeli (Kaufman) technique pronate the supinated forearm while the elbow is flexed to 90° and direct pressure stabilizes the radial head Nehar and Torch technique elbow held in extension and supination with distal traction and varus force with assistant pushing laterally on radial shaft and surgeon pushing medially on radial head elastic bandage technique tight application of an elastic bandage (esmarch) beginning at the wrist continuing over the forearm and elbow may lead to spontaneous reduction immobilization long arm cast or splint if an adequate reduction is achieved Closed Reduction and Percutaneous Pinning reduction technique K-wire joystick technique push technique blunt end of a large k-wire is pushed against the posterolateral aspect of the proximal fragment and pushed into place lever technique k-wire is placed into the fracture site and levered proximally if unstable after reduction a pin may be placed to maintain reduction Metaizeau technique involves retrograde insertion of a flexible nail across the fracture site fracture is reduced by rotating the nail Open reduction approach performed with lateral approach to radiocapitellar joint pronate to avoid the posterior interosseous nerve (PIN) fixation indicated if reduction is unstable avoid transcapitellar pins Complications Decreased range of motion most common complication (10-31%) loss of pronation more common than supination Radial head overgrowth 20-40% of fractures usually does not affect function Osteonecrosis 10-20% of fractures radial head in children is entirely cartilage and blood supply is primarily from the metaphysis up to 70% of cases occur with open reduction Nerve injury PIN may be injured Physeal arrest may lead to cubitus valgus deformity Synostosis most serious complication occurs in cases of open reduction with extensive dissection or delayed treatment Radial head malunion described in skeletally immature patients with intra-articular fractures can cause progressive radiocapitellar instability leading to chronic pain and degenerative changes Prognosis Risk factors for worse outcomes >10 years of age intra-articular involvement (50% overall complication rate) Need for revision surgery higher risk in intra-articular fractures (25%) versus extra-articular fractures (0%)