1 Introduction topenlarge
B2.1 and B2.2 fractures can involve the lesser or the greater tuberosity (as illustrated). Closed reduction with screw fixation is not recommended for lesser tuberosity fractures. Thus, we demonstrate only the case involving the greater tuberosity.
B2.3 fractures are characterized by a metaphyseal comminution. These fractures should not be treated with screw fixation because of the medial comminution.
2 Principles top
In some cases it is beneficial to perform a closed reduction and closed osteosynthesis. This induces no further damage to the soft-tissue and does not disturb the fracture zone including the fracture hematoma. It also does not disturb the subacromial space and allows prolonged immobilization postoperatively in a shoulder immobilizer.
The overall stability of cannulated screws alone is limited and 2-3 weeks postoperative immobilization in a shoulder immobilizer is recommended.
Risk of axillary nerve injury
The main structure at risk is the axillary nerve. The axillary nerve should be protected by limiting the incision to less than 5 cm distal to the acromial edge, by palpating the nerve, and by avoiding maneuvers that stretch the nerve during reduction and fixation. Remember the course of the nerve when placing K-wires.
3 Reduction and preliminary fixation topenlarge
Reduction/Fixation of the tuberosities
B2 fractures involve the surgical neck of the humerus and either the greater or the lesser tuberosity.
Sequence of repair:
- Reduction/fixation of the tuberosity (thereby converting the 3-part fracture into a 2-part situation)
- Reduction/fixation of the proximal humeral fragment to the shaft
For improved stability an additional (cannulated) lag screw can be placed in the lesser tuberosity.
Place rotator cuff sutures
Subscapularis and supraspinatus tendon
Begin by inserting sutures into the subscapularis tendon (1) and the supraspinatus tendon (2). Place these sutures just superficial to the tendon’s bony insertions. These provide anchors for reduction, and temporary fixation of the greater and lesser tuberosities.
Next, place a suture into the infraspinatus tendon insertion (3). This can be demanding, and may be easier with traction on the previously placed sutures, with properly placed retractors, and/or repositioning the arm.
Use of stay sutures
Anterior traction on the supraspinatus tendon helps expose the greater tuberosity and infraspinatus tendon.
Insert a preliminary traction suture into the visible part of the posterior rotator cuff …
… and pull it anteriorly. This will expose the proper location for a suture in the infraspinatus tendon insertion. Then the initial traction suture is removed.
Pearl: larger needles
A stout sharp needle facilitates placing a suture through the tendon insertion.
Reduction of the greater tuberosity
Direct reduction of the greater tuberosity fragment is performed by pulling the sutures or, …
… with instruments (eg, elevator) applied either through the incision (as illustrated) or through a separate stab incision.
Preliminary fix the greater tuberosity
Tighten and tie the transverse sutures in order to preliminarily fix the greater tuberosity fragment. Thereby, the 3-part fracture is converted into a 2-part situation.
Reduction of the head fragment
Distal traction, perhaps augmented with increased angulation, will help to reduce the fracture.
Use of an elevator
Sometimes, the incision allows insertion of an elevator to disimpact the humeral head, or to help to correct inclination/torsion and to restore a normal relationship of the medial fracture surface. The proximal fragment should be reduced anatomically to the shaft.
The actual process of reduction is done with image intensifier control.
Quite often, the humeral head is not stable enough and requires additional preliminary fixation using 2 or 3 K-wires.
Confirmation of reduction
The correct reduction must be confirmed in both AP and lateral views using image intensifier control.
4 Definitive fixation topenlarge
Fixation of the head fragment
Two or more percutaneously inserted screws linking the shaft fragment to the head fragment are inserted first.
Cannulated 3.5 mm lag screws (as illustrated), or non-cannulated small fragment lag screws are used according to the surgeon’s preference.
This illustration shows two screws inserted over guide wires.
Note: Washers may be advisable in poor bone stock. Generally, they are not preferable as they make the screw heads more prominent and may result in shoulder impingement.
Fixation of the greater tuberosity
Remove K-wires and guides wires from the shaft.
Fixation of the head fragment is followed by insertion of a screw into the greater tuberosity.
Again, in this case, the screw is inserted over a guide wire.
The illustration shows the completed osteosynthesis.
5 Final check of osteosynthesis topenlarge
Using image intensification, carefully check for correct reduction and fixation (including proper implant position and length) at various arm positions. Ensure that screw tips are not intraarticular.
Also obtain an axial view.
In the beach chair position, the C-arm must be directed appropriately for orthogonal views. Position arm as necessary to confirm that reduction is satisfactory, fixation is stable, and no screw is in the joint.