Cutting edge Orthopedics

22 • CUTTING EDGE - ORTHOPEDICS reduction in this fracture type. Additionally, pins can be preplaced into the distal fracture frag- ment. Reduction with the elbow in approximately 45° of flexion is confirmed on the AP radiograph first. The C-arm is rotated for a lateral image, and the sagittal plane deformity is then corrected. Rotational deformity may be corrected by applying pressure to the medial or lateral epicondyles. Once alignment appears acceptable on the lateral view, the preplaced pins are advanced across the fracture site and the far cortex. Acceptable reduction is confirmed on AP, lateral, and oblique views. The authors recommended a combination of two and three lateral-entry pin constructs and two crossed pins. However, they noted that their current technique is to use two lateral-entry pins and add a third lateral-entry pin for fractures that remain unstable [17]. Flexion-Type Fractures Flexion-type supracondylar humerus fractures are less common than extension-type [13]. Mahan and colleagues (2007) retrospectively compared flexion-type and extension-type injuries and found that flexion-type fractures tended to occur in slightly older patients (mean 7.5 years versus 5.8 years) [13]. Additionally, flexion-type fractures were more likely to require open reduction than extension-type fractures (31% versus 10%) [13]. Traditionally, CRPP of flexion-type frac- tures has been described by first correcting varus/valgus angulation and then applying a pos- teriorly directed force on the elbow flexed less than 90° and extending the elbow to allow the anterior periosteal hinge to assist with reduction [13]. Pins are then placed while the elbow is extended [13, 62]; however, this is technically challenging and may require a skilled assistant [62, 95]. Chukwunyerenwa and colleagues (2015) described a novel approach for closed reduction of flexion-type supracondylar humerus fractures [95]. The affected limb is placed on a radiolu- cent arm board with a rolled towel underneath the humerus at the level of the fracture. Coronal plane angulation is corrected first by varus or valgus stress with the elbow flexed approximately 45°. Fluoroscopy is utilized to confirm coronal plane alignment. The coronal plane reduction is maintained with slight traction on the forearm, with countertraction applied to the upper arm. The elbow is then flexed to 90° while continuing the gentle traction and countertraction. An axial force is then applied through the forearm, with the rolled towel acting as a fulcrum, to correct the sagittal alignment. The C-arm is rotated for a lateral image of the elbow to confirm reduction. Percutaneous pins are then placed as described in the "Technique" section above, except the elbow flexion is held at approximately 90° rather than hyperflexion. After pin placement is complete and stability of the fracture has been confirmed with live fluoroscopy, the elbow is immobilized at approximately 45° of flexion [95]. Postoperative care is performed as described above. Another technique, which is the authors’ preferred method, is to convert a flexion-type frac- ture into an extension-type fracture. This is performed by forcing the distal fragment posterior to the proximal fragment. Once that occurs, the standard methods of performing a closed reduction and percutaneous pinning can be performed. However, one must be careful when attempting this technique, as it may convert a flexion-type fracture into a Type IV extension-type fracture, with complete multidirectional instability.