Additional K-wires for plate positioning enlarge

Positioning wires (for plate location)

To ensure appropriate plate position, somewhat obscured by a small incision, it helps to place temporary K-wires that can be used for radiographically controlled guidance.
Insert 2 positioning K-wires, one at the lateral border the bicipital groove and the other at the tip of the greater tuberosity. (These positioning wires can be used for provisional tuberosity fixation.)

Position of additional K-wires (for plate position) enlarge

The anterior positioning K-wire sets the location for the anterior edge of the plate, 2-4 mm lateral to the bicipital groove.

The proximal positioning K-wire determines the proximal edge of the plate, 5-8 mm distal to the tip of the greater tuberosity.

Plate insertion enlarge

Insert plate

Identify the axillary nerve by palpating on the undersurface of the deltoid muscle. This helps protect it during plate insertion.
Insert the plate, assembled on an aiming device, under the deltoid muscle, and slide it distally under the deltoid and along the humerus. Always keep the plate in contact with bone.

Pearl: suturing the deltoid muscle To prevent extending the deltoid muscle split and increasing risk of axillary nerve injury, place a suture at the distal end of the split.

Attaching the plate to humerus enlarge

Attach plate to humerus

Position the plate in the planned and marked location on the proximal humerus. Fix it temporarily to the bone with K-wires. Proximally, two wires are placed through specific holes in the aiming device. Distally, use a percutaneously placed K-wire sleeve.

Confirm correct plate position with x-ray.

Drilling holes enlarge

Fix plate to the humeral head

Drill holes
Use an appropriate sleeve to drill holes for the humeral head screws. Do not drill through the subchondral bone and into the shoulder joint.

It may be necessary to remove one or more of the K-wires to make room for screws. Place first screws that are unobstructed and help stabilize the fracture.

Use percutaneous drilling and screw insertion sleeves to fix the plate to the humerus.

Avoid intraarticular screw placement enlarge

Avoiding intraarticular screw placement
Screws that penetrate the humeral head may significantly damage the glenoid cartilage. Primary penetration occurs when the screws are initially placed. Secondary penetration is the result of subsequent fracture collapse. Drilling into the joint increases the risk of screws becoming intraarticular.

Two drilling techniques help to avoid drilling into the joint.

Pearl 1: “Woodpecker”-drilling technique (as illustrated)
In the woodpecker-drilling technique, advance the drill bit only for a short distance, then pull the drill back before advancing again. Keep repeating this procedure until subchondral bone contact can be felt. Take great care to avoid penetration of the humeral head.

Pearl 2: Drilling near cortex only
Particular in osteoporotic bone, one can drill only through the near cortex. Push the depth gauge through the remaining bone until subchondral resistance is felt.

Determination of proper screw length enlarge

Determine screw length
The intact subchondral bone should be felt with a depth gauge or blunt pin to ensure that the screw stays within the humeral head. The integrity of the subchondral bone can be confirmed by palpation or the sound of the instrument tapping against it. Typically, choose a screw slightly shorter than the measured length.

Screw insertion into humeral head enlarge

Insert screw
Insert a locking-head screw through the screw sleeve into the humeral head. The sleeve aims the screw correctly. Particularly in osteoporotic bone, a screw may not follow the hole that has been drilled.

Number of screws and location enlarge

Number of screws and location
Place a sufficient number of screws (often 5) into the humeral head. The optimal number and location of screws has not been determined. Bone quality and fracture morphology should be considered. In osteoporotic bone a higher number of screws may be required.
Remember the plate lies deep to the axillary nerve. Screws should not be place through the danger zone where the nerve may be injured.

Fixation of lesser tuberosity (if involved) enlarge

Lesser tuberosity fixation
If the lesser tuberosity is involved, lag screw fixation might be considered. This technique may be superfluous when appropriate tension band sutures are placed through the rotator cuff insertions. Another option is one or more absorbable polymer pins.
If in doubt, once the sutures are secure, check the stability of the lesser tuberosity clinically by rotating the arm. If there is any micro movement visible or palpable consider additional fixation, which is typically placed after the rest of the fixation.

Screw insertion into humeral head enlarge

Insert screws into humeral shaft

Insert two to three screws into the humeral shaft, below the danger zone, with aiming device and appropriate, percutaneously placed screw insertion sleeves.

Additional tension band suture enlarge

Tension band sutures in addition to plate and screws

Supplementary rotator cuff tendon sutures provide additional stability. Varying the arm position helps to place them through such a small incision. The sutures should be inserted close to the bony insertion sites of subscapularis, supraspinatus, and infraspinatus tendons. They are tied to the plate to resist muscle forces and improve plate anchorage.