Humerus, proximal: extraarticular multifragmented fracture with extension to the diaphysis (11-A3 and 12-C3)

10.1055/b-0034-87612

Humerus, proximal: extraarticular multifragmented fracture with extension to the diaphysis (11-A3 and 12-C3)

Christoph Sommer

Case description

A 23-year-old man fell while snowboarding and sustained a multifragmentary extraarticular fracture to the left proximal humerus without neurovascular impairment.

Indication for MIPO

This unstable proximal humeral fracture with extension into the shaft is more favorable for operative treatment. It is difficult to maintain closed reduction and undergo nonoperative treatment. It could also be treated conservatively with a good outcome. Advantages of operative stabilization include functional aftercare without immobilization, allowing use of the arm and hand soon after surgery. If surgical treatment is chosen, this comminuted fracture is best treated by a minimally invasive approach, where the fracture is splinted in the correct alignment but the fragments are not anatomically reduced. Either an intramedullary nail (antegrade) or a plate can be used for fixation. The advantage of a plate is that the rotator cuff will not be injured and therefore postoperative shoulder problems should be minimized.

The MIPO technique (anterolateral deltoid-split approach) allows easy access to the plating zone on the lateral aspect of the humerus in the most proximal part, but it can endanger the axillary nerve if the incision is extended more than 5 cm distal to the acromion and the radial nerve at the level of the distal end of the plate.

a–f Preoperative x-rays and CT scans demonstrate a fracture of the proximal humerus from the surgical neck to the midshaft with several displaced fragments. There is a nondisplaced fracture line extending into the greater tuberosity.

Preoperative planning

The fracture pattern must be considered when planning fixation. A bridging construct using a long plate with adequate fixation in the proximal and distal main fragments is planned to obtain optimal stability. LHSs particularly in the proximal head fragment are advantageous to provide enough stability for early motion. The one large intermediate fragment, which is pulled medially by the inserting pectoral muscle, needs to be aligned and fixed by one or two screws. The plate will act as a reduction tool itself by pulling the intermediate and distal main fragments to it during surgery. In this case with involvement of the greater tuberosity, even if undisplaced, the plate must be placed onto the lateral aspect of the proximal humerus to provide enough stability. Therefore, an anatomically contoured plate, such as the long LCP PHILOS plate, is ideal.

The preoperative plan in Fig 12.2-2 shows the order of screw insertion. The plate is first fixed proximally (1) with an LHS then distally (2) using a cortex screw. Cortex screw number 3 is used as an indirect reduction screw to bring the intermediate fragment in. Once alignment is checked and in a good position, the remaining LHSs (4–10) are inserted.