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, or with properly placed retractors.
Variations depending on the approach chosen
Inserting sutures into the infraspinatus tendon is easier with a lateral approach. A) shows a deltopectoral approach and B) an anterolateral (transdeltoid) approach.
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.
Pearl: use of retractors
Use of blunt, curved Hohmann retractors underneath the deltoid muscle can be helpful to expose the humeral head.
Similarly, a so-called delta retractor may improve deltoid retraction.
Pitfall: use of forceps or clamps in osteoporotic bone
Grabbing bone fragments with a forceps or clamp will typically increase comminution of osteoporotic bone. This should be avoided by using sutures as “handles” for manipulation and reduction.
Extension of exposure
Due to the limited visual and radiological control during reduction of the head split it is advised to expose the humeral head in order to obtain better visualization.
Incise any soft tissues over the fracture line, and continue proximally between supraspinatus tendon fibres.
Note: If a cranial extension is needed, it should be carried into the supraspinatus tendon (A) and not into the rotator interval (B). This is because the typical “intertuberosity” fracture line of a four-part fracture is actually lateral to the bicipital groove, and thus through the greater tuberosity.
Reduction of the head split
First, try to reduce the humeral head split using digital pressure, or periosteal elevators.
Check the reduction under image intensifier control. Be aware that different positions of the image intensifier are necessary to properly assess the reduction of the head split since the assessment is strongly dependent on the projection. Especially a transaxial view in supine patient positioning is beneficial.
The reduction of the head fragments may be secured with two K-wires.
- In some cases, it might be demanding or just not possible to fix the head fragments with K-wires. Therefore, it might be helpful to fix the fragments against the glenoid temporarily.
- In special situations it might be necessary to perform an open reduction and preliminarily fix the humeral head fragments outside the body on the back table and to replant the fixed humeral head later.
- Bone substitutes underneath the humeral head might help to increase stability.
After fixation of the head split one should try to reduce the humeral head to the humeral shaft and secure the reduction with additional 2 or 3 K-wires inserted axially.
Check of reduction
Perform the reduction under image intensifier control.
Note: impaction at the medial side
Anatomic reduction of the calcar is not needed in all cases. A slight impaction at the medial side might even increase the stability of the reduction.
Reduce the tuberosities
If the humeral head is properly reduced and the correct inclination of the humeral head is achieved, the tuberosities can now easily be positioned underneath the humeral head. Pull the sutures between the subscapularis and the infraspinatus tendons horizontally …
… and tie them together.
Note: If K-wires interfere with proper reduction of the tuberosities, they should be replaced as necessary.